فصلنامه پژوهشهای علوم دامی ایران
سال سیزدهم شماره 3 (پاییز 1400)

Rumen growth and development is a complex process that is highly influenced by nutritional status. The characteristics of a starter diet and nutrients such as fat, protein and forage are closely linked to proper rumen growth and successful weaning, which can ultimately affect the future of alternative heifers and milk production. Consumption of fat sources due to reduced dietary dust, increased dietary energy and reduced ability to produce methane in ruminal fermentation in ruminants has been favored. Research has been shown that the use of fat in the diet of dairy calves has increased efficiency. However, the level of fat consumed, its source, and individual fatty acid ratios appear to impact the performance of dairy calves as well. Regardless the dietary fat inclusion and energy status, researchers have reported that the use of forage in the diets of dairy calves has improved ruminal function and growth function, stimulated rumination and reduced non-nutritional behaviors. However, the use of high levels of forage in dairy calves will lead to poor rumen development, gastrointestinal filling, reduced feed intake, and ultimately reduced growth in dairy calves. Due to the fact that fats could cover on the dietary fiber and prevent the access and binding of microorganisms in the digestive tract, the digestion of fiber is reduced and consequently the consumption of food is also affected. Therefore, due to these contradictory assumptions and also due to limited studies on the interaction between fat consumption and fiber source level in dairy calves, an experiment examining the effects of soybean oil (SO) on starter diets with or without alfalfa hay inclusion (AH) on performance, body Growth, ruminal fermentation, and blood metabolites were performed in Holstein dairy calves.

The present study was conducted in Avin-Dasht Industrial Livestock located in Takestan city of Qazvin province. For this purpose, 40 newborn Holstein calves with an average age of 3 days and an average weight of 39 ± 2.2 kg with 4 experimental diets (10 repeat/ each) were used completely randomly as a 2 × 2 factorial design. Experimental diets include: 1) No SO supplementation with no AH (NSO-NAH); 2) No SO supplementation with 15% AH inclusion (NSO-AH); 3) SO supplementation with no AH (SO-NAH); 4) SO supplementation with 15% AH inclusion (SO-AH). The milking plane for calves and the volume of milk consumed by the end of the period were similar for calves in all treatments. Study was initiated from d-3 of age, weaned on d 63 and calves had free access to starter diet and water throughout the study. During the experiment, to determine the daily feed intake, before the fresh starter offering, the feed residual was collected and recorded. The chemical composition of the food treatments was measured. Growth factors were measured at the time of entry into the experiment and at weaning day as last day of the experiment. The calves were weighed on 10-d intervals until the end of the experiment (d -60). Growth parameters were evaluated on initial day and on the final day of the experiment. Rumen samples were taken was taken and the concentration of volatile fatty acids was determined using a gas chromatography. The blood metabolites and liver enzymes concentrations were measured using commercial kits of Pars Azmoun Company and by calorimetry method with spectrophotometer. Data were analyzed using SAS statistical software and MIXED procedure with main effect of SO, and AH, and their interaction. The significance was considered at P < 0.05, and tendency was considered when P value was between 0.05 and 0.10 in the current study.

The results of the present study showed that starter intake was influenced with the interaction effect between SO and AH, and the lowest starter diet intake was for SO-AH diet (P < 0.05). The average daily gain was tended to be lower in SO-AH diet and hence the least BW was observed for this treatment at weaning time (P < 0.05). Results show that heart girth, body length, body barrel, hip width did not differ among treatments. However, wither height was reduced in calves fed SO when it was along with AH. Both SO and AH inclusion in starter diet reduced hip height in the current study. The total short chain fatty acid concentration was reduced in SO-AH treatment compared with others. Feeding forage reduced propionate and butyrate but increased acetate concentration in ruminal fluid. The lowest blood glucose concentration was found in dairy calves fed SO-AH treatment in the current study (P = 0.03). The blood concentrations of total protein were reduced, but cholesterol was increased in SO supplemented calves. The concentration of blood urea nitrogen was increased when calves fed AH in starter diet (P = 0.03). However, in contrast, the beta-hydroxybutyrate concentration in the blood of calves fed alfalfa hay was reduced (P = 0.02).

The experiment results indicated that supplementation of SO and AH separately in the starter diet of dairy calves had a negative effect on ruminal fermentation and hip height. By supplementing SO, an increase in serum cholesterol was observed, but it reduced the total protein in the serum. The results of blood urea concentration showed that the inclusion of AH increased its concentration; however, with respect to the beta-hydroxybutyrate concentration, it was reduced by AH inclusion in starter diet. The results showed that concurrent feeding of SO (3%) and AH (15%) in the starter diet of pre-weaning dairy calves, decreased the concentration of volatile fatty acids in rumen, blood glucose, weaning BW and wither height. Due to the current experimental conditions, the concurrent feeding of SO with AH is not recommended due to the negative effects of their interaction on growth performance, ruminal fermentation and as well as on some blood metabolites during pre-weaning period.

 Since the legislation of European Union has prohibited the use of growth-promoting antibiotics such as monensin, scientists have been interested in alternatives to manipulate rumen fermentation. The use of growth-promoting antibiotics in animal feeds is banned in Europe due to potential risks such as the spread of antibiotic resistance genes or the contamination of milk or meat with antibiotic residues. Recently, essential oils have been increasingly evaluated to replace or facilitate reductions in the use of antibiotics. The most effects of plant essential oils, especially cloves and savory oils, are their antioxidant effects and their effects on the metabolism of ruminal microbes. The antiprotozoal effects of clove extract have been proven in the studies in vitro by gas production technique. Few studies have been done on the effects of clove oil, especially the savory oil, on the digestive properties in the country. Also, no study was found on the interactions of these essential oils in the experiments in vitro. Thus, the aim of this study was investigated to evaluate the effects of clove and savory oils on gas production and in vitro fermentation process and estimation of gas production parameters of feedstuffs (alfalfa hay and barley grain).

Experimental treatments were included control (basal feeds without additive), basal feeds supplemented with three levels of clove oil (0, 250, 500 mg) and three levels of savory oil (0, 250, 500 mg) per kg of DM in a rumen culture. Ruminal fluid was collected from two fistulated sheep (49.5±2.5 kg). All samples isolated from the rumen were withdrawn 2 h after the morning ration had been consumed. Collected rumen contents were strained through four layers of cheesecloth and brought immediately to the laboratory. Gas production technique was used to detect the fermentation parameters of the treatments. About 200 mg of basal diet (alfalfa hay and barley grain, 1:1, with clove and savory oils) were incubated in 100ml glass syringes and 30ml of incubation liquid were added and were incubated in 39 C° water bath. The gas production was measured in 2, 4, 6, 8, 16, 24, 48, 72, 96, 120h. Three parallel syringes of each treatment were prepared in this experiment in a completely randomized design in a factorial arrangement. They were used to measure the gas production parameters (fermentable fraction (b) and rate (c) of gas production) cumulative gas production, organic digestibility and metabolizable energy of treatments until 120 h. In the present study, digestible organic matter, metabolizable energy, and production of volatile fatty acids were estimated based on the presented equations.In the second experiment, Peptostreptococcus anaerobic was isolated from the ruminal fluid, cultured in the medium of BAAA) Bile EsculinAzideAgar(, and evaluated by different levels of cloves and fennel essences in a randomized complete design with sixteen treatments and three replicates using Duncan test at level 0.05. Experimental levels in this experiment including: 20, 35 and 40 µl of cloves essence, 20, 35 and 40 µl of fennel essence, 20 µl of fennel essence + 20 µl of cloves essence, 20 µl of fennel essence + 35 µl of cloves essence, 20 µl of fennel essence + 40 µl of cloves essence, 35 µl of fennel essence + 20 µl of cloves essence, 35 µl of fennel essence + 350 µl of cloves essence, 35 µl of fennel essence + 40 µl of cloves essence, 40 µl of fennel essence + 20 µl of cloves essence, 40 µl of fennel essence + 35 µl of cloves essence, 40 µl of fennel essence + 40 µl of cloves essence, control.Statistical analysis of data was performed by SAS statistical software (9.1 version). Duncan's multiple test range was conducted in level 5%.

High levels of savory oil were increased gas production in the first hours (p<0.05), but clove oil was reduced gas production in 8-24 hours (p<0.05). Although, few data have been published on the interaction effects of the use of the essential oils, as well as on the effects of savory oil on fermentation parameters. The amount of gas production (b) tend to be decreased (P=0.06) due to the simultaneous use of savory and clove oils. Different levels of savory oil had no effect on estimated organic matter digestibility, metabolizable energy, and volatile fatty acids. But, with increasing the levels of clove oil, the amount of estimated organic matter digestibility, metabolizable energy tend to be decreased (P=0.09). In the microbial experiment, after incubation of peptostreptococcus anaerobic in medium of Bile AesculinAzideAgar and adding different levels of cloves and fennel essences was observed that all levels of treatments were significant (P<0.05); the highest growth of bacteria was related to treatment 11 (35 µl of fennel essence + 350 µl of cloves essence). This result showed ammonia-producing bacteria known peptostreptococcus anaerobic is inhibiting by different levels of clove and savory essences and finally resulting in the decrease of rumen fluid Ammonia nitrogen.

 According to our results we can conclude thatusing savory oil improves ruminal fermentation in vitro and with increasing the levels of savory oil, the amount of gas production, the organic matter digestibility, the metabolizable energy and volatile fatty acidsconcentration were decreased. Also in this study, were shown the co-effects of simultaneous use of savory and clove oils on the reduction of gas production. Therefore the effects of essential oils should be considered. For further studies, it is suggested that the effect of essential oils along with various sources of energy, such as pectin, starch, and various protein sources, should be studied in vitro and in vivo. Also, consideration of other changes in fermentation products such as ammonia nitrogen, methane and the composition of the microbial population in these experiments can also be of particular importance.

Mummies are the brown or black hydrocarbon that are produced deep layers of earth or mountain and contain a significant percentage of benzoic acid, humic acid, and folic acid, fatty acids, inulin, and resins. The mummy probably reduces the acidity of the digestive content and increases the activity of its microbial acid-loving population, and ultimately increases the digestibility of nutrients (protein and fat) and improves body weight gain. On the other hand, pulicariap gnaphalodes is an herbaceous, perennial, with straight stems, dense leaves and hazelnut fruit. The pulicariap gnaphalodes store energy in the form of fructan and inulin. The most active component of it is 8, 1-cinnamol (22.93%), alpha pinene (8.13%), amorphous-9, 4DN-2-L (8.36%), myrtenol (7.24%). Percent). Quercetin and its derivatives are the main flavonoids in pulicariap gnaphalodes. Inulin plays a prebiotic role in poultry diets and improves the intestinal environment. Improving the intestinal environment increases the immune response and growth performance. The strong antibacterial properties of Pulicaria gnaphalodes due to its polyphenolic compounds, especially quercetin, has the ability to neutralize free radicals and reduce feed conversion ratio. Therefore, this study was carried out to investigate the effect of Pulicaria gnaphalodes extract and mummy on growth performance, blood biochemical indices, immune system and jejunal morphology of broiler chickens.

A total of 360 one-day-old Ross 308 chicks was used in 9 treatments (three levels of Pulicaria gnaphalodes extract (PGE) (0, 100, and 200 mg/kg) and three levels of mummy (0, 20 and 40 mg/L). 3 replicates, and 10 birds. The experiment was done in a completely randomized design with 3 × 3 factorial design. The growth performance indices were recorded at the end of each period of starter (1-10 days), grower (11-24 days), finisher (25-42 days). At the end of the experiment, two birds from each replicate were slaughtered to study the relative weight of the carcass components. The blood of two birds of each replicate were gathered, then the sera were extracted and freezed at -20 oC at 42 days. To study the jejunal morphology, a slice of 1 cm from the midpoint of jejunum from each slaughtered birds were separated, then it was placed in formalin until send laboratory. The statistical analyses were done with SAS software with GLM procedure. The Tukey test was used to compare average treatments.

 The results showed that growth performance traits including feed intake, body weight gain and feed conversion ratio did not affect by the interaction effects of mummy powder and PGE, except for body weight gain index and feed conversion ratio that was affected at the finisher period. The highest weight gain was observed in broilers fed 20 mg of mummy + 200 mg of PGE compared to the control group. Mummies contain a significant percentage of benzoic acid, humic acid, and folic acid, fatty acids, inulin, and resins. The mummy probably reduces the acidity of the digestive content and increases the activity of its microbial acid-loving population, and ultimately increases the digestibility of nutrients (protein and fat) and improves body weight gain. The PGE also is an energy source in the form of inulin, inulin plays a prebiotic role in poultry diets and improves the intestinal environment. Improving the intestinal environment increases the immune response and growth performance. Due to its polyphenolic compounds, especially quercetin, PGE has the ability to neutralize free radicals and reduce feed conversion ratio. The mummy compares to control significantly increased carcass weight and breast relative weight (P <0.05). Both experimental dietary treatments significantly increased liver, bile, heart, spleen and relative weight bursa (P <0.05). The interaction of PGE and mummy increased the antibody titer against SRBC and immunoglobin M and G compared to control (P <0.05). Increasing the relative weight gain of lymphoid organs is a sign of the development of the immune system. Pandey et al. (28) have reported that quercetin supplementation in poultry feed increases the relative weight of Fabricius and Thymus. The interaction effect of PGE and mummy powder at the level of 40 mummy and 100 extracts improved the relative weight of lymphatic organs and antibody titer against SRBC. In this study, no significant alterations were observed in the concentration of blood protein, triglyceride, and high-density lipoprotein of broilers fed different dietary treatments. The birds fed 40 mummy and 200 PGE caused a decrease in LDL concentration, cholesterol, and aspartate aminotransferase activity compared to control (P <0.05). Phenolic compounds in herbal extracts reduce blood cholesterol by lowering the activity of key enzyme-regulating cholesterol-building enzymes (3- hydroxy-3-methylglutaryl coenzyme A) HMG-CoA liver reeducates.

 These findings showed that the addition of mummy and PGE at 20 mg/l of water and 200 mg/kg of feed together respectively in the diet may improve growth performance, reduce abdominal fat and blood lipids and liver enzyme activity in broiler chickens.

 Corn is one of the most important cereals used for poultry feeding due to its high starch, available energy and protein. Starch is an important source of energy in cereals and it is important to pay attention to its availability. In the cell wall of the endosperm, cereal grains, contain some of the structural carbohydrates that are soluble in the small intestine and have high molecular weight which may cause viscosity. Positive physical and chemical changes by steam conditioning, include starch gelatinization, denaturation of digestive enzyme inhibitor proteins, and cell wall breakage. Regardless of NSP content, some amounts of nutrients pass through the birds gut without being digested in corn-soy diets. Supplementing broiler diets with exogenous enzymes to degrade NSP has been a useful tool to release energy and nutrients, which can increase the value of low quality corn in poultry feeds and improve growth performance.

This project was conducted at the Poultry Research Center of Ferdowsi University of Mashhad. A batch of corm grains was obtained from a commercial supplier and ground in a hammer mill to pass through screen sizes of 3.0 and 5.0 mm for starter (1-10 d) and grower (11-24 d) periods, respectively.First trial: Apparent metabolizable energy (AME) and digestibility of corn crude protein (CP) and dry matter (DM) were determined in basal diets, which the corn was the sole source of ME and CP. Basal diets contained the conditioned (at temperatures of 55, 70 and 85 °C) or unconditioned corn and was or was not supplemented with enzyme (Rovabio®; Adisseo, France) at the amount of 0.5 g/kg diet. Total excreta collection was performed with 144 chicks in 8 treatments with 6 replicates and 3 birds each, during 7 to 9 days of age using battery cages. Excreta from each replicate cage were collected early in the morning and in the evening. After removing feathers, feed residues, and other contamination sources, excreta were air dried in an oven at 55 °C for 72 hours. Then the excreta were weighed and homogenized, then a sample of approximately 30% of the excreta was randomly separated and kept at -20 °C to further analysis. Then, dried excreta samples were ground in a micro-mill and submitted to the Animal Nutrition Lab. Feed and excreta dry matter, gross energy, and nitrogen contents were determined.Second trial: In second trial, 576 d-old broilers from Ross 308 strain with initial BW of 43 g, were fed with mash diets containing conditioned corn which was or was not supplemented with enzyme, during starter (1-10 d) and grower (11-24 d) periods. The experiment was done based on a completely randomized design with 4 × 2 factorial arrangement of treatments evaluating four corn conditioning temperatures (unconditioned and conditioned at 55, 70 and 85 °C) and two enzyme (Rovabio®; Adisseo, France) levels (0 and 0.5 g/kg diet). chicks were assigned under eight treatments with 6 floor pen replicates. Each floor pen of 1.2 × 1 × 0.8 m (L × W × H) included 12 chicks (6 male and 6 female, equally for all replicates). Floor pens were covered with 1.5 Kg/m2 of wood shavings. Four of eight experimental diets were supplemented with 0.5 g/kg of a multiple enzyme complex composed of cellulases, 6400 unit; β-glucanase, 2000 unit and Xylanase 22000 unit per gram (Rovabio®; Adisseo, France). Corn-soy-based diets were formulated to meet the Ross 308 strain recommendations for major nutrients for starter and grower phases. Feed and water were supplied for ad libitum consumption throughout the trial with a tube feeder and two nipple drinkers in each floor pen. House temperature was initially set at 32 ◦C on day one and was decreased linearly by 0.5 ◦C per d to a temperature of 21 ◦C. During the experiment, the lighting program consisted of 23L:1D. A completely randomized design with 4×2 factorial arrangement was used in the both trials. Main factors were included corn conditioning temperatures (unconditioned and conditioned at 55, 70 and 85 °C) and two enzyme levels (0 and 0.5 g/kg diet). The data were analyzed using generalized linear model (GLM) procedure, SAS software (9.4) and the differences between them was tested by Duncan's test (P ≤ 0.05).

 Conditioning and enzyme supplementation had no significant effects on AME and CP digestibility. Conditioning at 80 °C decreased DM digestibility of corn in comparison to control group (P<0.05). Enzyme had no significant effect on DM digestibility. In second trial, there were no significant differences in productive performance among treatments during 11-24 d and the accumulated period (1 to 24 d). Feed conversion ratio (FCR) of the birds fed diets containing conditioned corn at 85 °C was significantly more than that of 55 and 70 °C diets during 1-10 d; although it was not significantly different with control group. Neither corn conditioning nor enzyme supplementation had significant effect on carcass characteristics, and small intestine segments length and weight at 24 d. Enzyme supplementation significantly increased villi height and width at 24 d (P < 0.05). Corn conditioning significantly increased villi width and crypt depth but decreased villi width to crypt depth ratio. Bifidobacteria, E. coli and clostridia population in the ileal contents were not affected by corn conditioning and enzyme supplementation. Lactobacillus population was increased by enzyme addition and also by corn conditioning at temperature 70 °C in compare to control group. These results are in agreement with those reported by Gonza´lez-Alvarado et al. (2007) who reported no significant differences in growth performance of broiler chicks fed heat treated corn-based diets. However, negative effect of higher pelleting temperatures on the WG of birds fed corn-based diets have also been reported. They showed that pelleting a corn–soybean meal diet at 65 ◦C resulted in higher weight gain compared to the basal mash diet and diets pelleted at 75 and 85 ◦C.

 In general, corn conditioning and enzyme supplementation did not improve growth performance and nutrient utilization but improved gut histomorphology and microbial status.

The embryonic stage is the most critical and sensitive period in development of organisms especially the birds. In ovo injection is a good instrument for feeding the essential nutrients to growing embryo in birds. The in ovo application of nutrients provides the further benefits to the growth and development of the growing embryo. This experiment was conducted to investigate the effects of in ovo injection of synbiotic solution on hatchability, quality indices, weights and blood indices of one-day old chicks in Japanese quail.

Three hundred and seventy five quail eggs were allocated to five treatments of control (without injection), 2 ml injection of distilled water and injection of 1, 2 and 4 μg synbiotic solution. On day 8 of incubation, the eggs were randomly divided to five groups each containing 75 eggs. Injection was done on day 8 of incubation into the air sac of the eggs by insulin syringes. The injection site on the top of the eggs was sterilized by ethanol 70% and a small hole was made with needle of 27G. After injection, the holes were sealed by paraffin and returned to the incubator. At the end of day 17, the unhatched eggs were opened to identify the infertile eggs or dead embryos. On hatching day, two chicks were used to determination of chick quality. All the hatched birds were weighted. Then all the hatched chicks were reared up to day 35 of age in the separate pens (five replicates pen for each treatment). The performance factors (weight gain, feed intake and feed conversion ratio) were determined during the experimental week. Moreover, the carcass characteristics (carcass, thigh and breast) internal organs (liver, gizzard, intestine and heart) were determined at the end of the experiment (35 days of age). All the experimental data were introduced to SAS (9.1) in a completely randomized design with five treatments and five replicate each. The means were further separated using Tukey-Kramer multiple comparison test.

The results showed that in ovo injection had no effects on quality parameters of newly hatched chicks (P>0.05). Moreover, synbiotic injection to the quail eggs caused a decrease in hatchability (P<0.05). Furthermore, the synbiotic injection did not affect the weight of day old chicks (P>0.05). No effect of synbiotic injection was observed during weeks 1, 3, 4 and 5 (P>0.05). In week 2, injection of distilled water and synbiotic caused higher weight gain as compared to control (P<0.05) whereas there were no significant differences between the other treatments. Distillated water or synbiotic injection did not affect feed consumption during weeks 1 and 4 (P>0.05) but changed the feed intake during weeks 2, 3 and 5 (P<0.05). During week 2, 1 μg synbiotic injection increased the feed intake as compared to the other treatments whereas no significant differences were observed between the others during this week. During week 3, injection of 1 and 2 μg synbiotic caused the higher feed intake in comparison to other treatments and the highest feed intake belonged to the birds with 2 μg synbiotic injected eggs. In week 5, injection of 1 and 2 μg synbiotic caused a higher feed intake but only the effect of 2 μg synbiotic injection was significant (P<0.05). Moreover, no effects of in ovo injection of synbiotic were indicated for carcass characteristics (carcass, breast and thigh), internal organs (liver, heart, intestine and gizzard) and blood indices (urea, uric acid, glucose, triglyceride, creatinine and protein) (P>0.05). No significant differences were observed between the treatments for blood enzymes of alkaline phosphatase and aspartate aminotransferase (P>0.05).

According to the results of current experiment, synbiotic in ovo injection to quail eggs had no effects on weight and quality of one day old chicks but caused the lower hatchability. In ovo injection of 1 μg synbiotic to the air sac of the quail eggs improved the weight gain of hatched chicks after hatch but causes the higher feed intake and feed conversion ratio. Injection of higher synbiotic more than 2 μg to the air sac of quail eggs increases the feed intake and feed conversion ratio of quail chicks. Moreover, synbiotic injection did not affect carcass characteristics, internal organs, blood enzymes and indices of quails.

 Wheat is one of the important ingredients for preparing poultry diets. However, wheat contains some anti-nutritional factors such as non-starch polysaccharides (NSP) which enhance digesta viscosity and thus decrease nutrients digestion and absorption. These negative effects could damage performance and feed efficiency. Increase in digesta viscosity also imposes negative effects regarding intestinal epithelium. Vitamin A (vitA) is an important nutrient in maintaining the health of intestinal epithelium. Since wheat is deficient in vitA content and also wheat-based diets (WBD) can cause less vitA absorption from the intestinal lumen (by disturbing lipid digestion and absorption), it seems that supplementation of the WBD with vitA would be effective in mitigating some of the anti-nutritional effects of the WBD.

In this study, the effect of a WBD supplemented with different levels of vitA on performance and immune system of broiler chickens were investigated. Five dietary treatments were prepared as follow: 1) WBD supplemented with 1500 IU vitA/kg (control); 2) WBD supplemented with 4500 IU vitA/kg; 3) WBD supplemented with 7500 IU vitA/kg; 4) WBD supplemented with 10500 IU vitA/kg; and 5) WBD supplemented with 13500 IU vitA/kg. Two hundred Ross 308 male day-old broiler chicks in a completely randomized design with four replicates of ten chicks per each were used. Feed intake (FI), body weight gain (BWG), and feed to gain ratio (FCR) were recorded periodically during the experiment. Sheep red blood cells (SRBC) antigen (2%) was injected to thigh muscle of two birds from each replicate on day 28. Seven and 14 days after injection, blood samples were collected and antibody titers against SRBC were measured. In order to evaluate cutaneous basophil hypersensitivity (CBH) response, on day 41, eight chicks per treatment were randomly selected and phytohemagglutinin (PHA-P) was injected (100 µg) subcutaneously into toes web of each bird. 12 and 24 hours after injection, the thickness of the web was measured and CBH response was calculated. At the end of the experimental period (day 42), two chickens from each replicate were selected randomly and euthanized. Abdominal cavity was opened and digestive organs as well as the spleen, bursa of Fabricius, liver, and abdominal fat pad were excised and weighted. The small intestinal parts including duodenum, jejunum, and ileum were excised, weighted, and measured in length. Afterward, the whole carcass and carcass parts were weighted. The weight of each organ was then expressed compared to the live body weight. For the viscosity measurement, jejunal and ileal contents were collected and centrifuged (500 ×g, 15 min). The supernatants were then used for the viscosity measurement. Serum malondialdehyde (MDA) was measured as an indicator of lipid peroxidation. For measurement of total tract apparent digestibility (TTAD) of nutrients, chromium oxide (Cr2O3) was used in diets as an external marker. On day 21, samples of excreta were collected every 6 hour (four samples during 24 hours) and pooled. Feed and excreta samples were then analyzed for crude protein (CP) and ether extract (EE). Chromic oxide concentration in feed and excreta samples was measured and TTAD of CP and EE were then calculated. The collected data were analyzed using the general linear model (GLM) procedure of the SAS software.

 In starter period, supplementing the WBD with 10500 or 13500 IU vitA/kg, significantly reduced FI compared to groups consuming 1500 or 4500 IU vitA/kg of diet. This could be attributed to vitA reservoir in yolk sac at the life beginning which increases the probability of vitA toxicity with higher levels of vitA in early growth period. No significant difference was found for FI among treatment groups during grower period (22-42 days of age) as well as entire period (1-42 days of age) of the experiment. VitA at different levels used in this study, had no significant effect on BWG and FCR during starter, grower, and the entire period of the experiment. The highest production index was seen in the group receiving the diet supplemented with 7500 IU vitA/kg. Furthermore, the lowest relative feed cost per kg of live weight or carcass weight were seen in groups receiving diet supplemented with 7500 and 4500 IU vitA/kg, respectively. Feeding WBD containing 13500 IU vitA/kg caused a significant increase in anti-SRBC titer on 7 days after injection, compared to control group. According to this result, it seems that high level of dietary vitA (13500 IU/kg) would be effective in stimulating antibody-mediated immunity in broiler chickens. Improvement in humoral immune responses of broiler chickens by supplemental vitA has been reported in other studies. No significant difference was seen regarding CBH response on 12 and 24 hours after PHA injection, among treatment groups. There was no significant difference among treatment groups as for spleen and bursa of Fabricius weights. VitA at levels of 4500 and 7500 IU/kg of diet, caused a significant decrease in serum MDA concentration. Decrease in serum MDA concentration by increasing dietary vitA level indicates anti-oxidative effects of this vitamin. Supplementation of the WBD with vitA at levels used in this study had no significant effect on the length and weight of duodenum and jejunum. However, vitA at 4500 and 7500 IU/kg of diet, decreased ileum relative weight. Digesta viscosity in the jejunum was decreased by dietary vitA at levels higher than 7500 IU/kg. In addition, abdominal fat pad weight was decreased by supplemental vitA at 4500 IU/kg of diet, comparing to the control. Supplementing the WBD with different levels of vitA had no significant effect on the TTAD of CP and EE.

 The results of this study showed that supplementation of the WBD with vitA at 7500 IU/kg, would not affect performance but could stimulate humoral immune response (antibody production) and anti-oxidative defense of the broiler chickens. Also, vitA supplementation at the level of 7500 IU/kg of the diet improved production index and decreased feed cost per kg of live weight. Furthermore, it has been evidenced that higher levels of supplemental vitA (more than 1500 IU/kg as the requirements) could be effective in decreasing abdominal fat pad in broiler chickens.

Commercially available feed-grade crystalline amino acids have provided an opportunity for nutritionists to formulate low CP cost-effective diets while maintaining optimal protein utilization by birds. Lysine is the first limiting amino acid in practical diets for broilers when soybean meal is not the major protein source. Lysine supplementation under such circumstances almost becomes unavoidable in particular when dietary CP contents are to be reduced and when using the concept of ideal amino acid ratio in which lysine is used as a reference amino acid. L-Lysine HCl, which contains a minimum of 78% lysine is the dominant source of lysine for addition to poultry diets. L-Lysine sulfate products have minimum lysine contents of 46.8% in Biolys60 (Degussa AG, Frankfurt, Germany) or 51% in Lysine Plus (CJ Biotech Co. Ltd., Liaocheng, Shandong, China). A recent study reported that the bioefficacy of L-lysine sulfate relative to L-lysine HCl was similar when using daily gain and feed conversion of young pigs as the response criteria. In addition, several other swine and broiler experiments had been conducted to compare the bioefficacy of lysine in L-lysine sulfate and L-lysine HCl. Most of these studies used animal performance as the main response variable. However, very little research has been conducted to determine the effects of different lysine sources on plasma metabolites and bone characteristics of broiler chickens as the response variable. Therefore, the present study was conducted to examine the comparative effects of L-lysine sulfate and L-lysine HCl in broiler chickens using growth performance, blood metabolites and bone parameters as response variables.

In this experiment compared the effects of L-Lysine-hydrochloride (Lys) and Biolys-Sulfate (BioLys) on broiler chickens’ performance and Immune Response. In a completely randomized design, 200 Ross-308 broiler chickens were allocated to 5 dietary treatments with 5 replicates and 8 birds in each. Dietary treatments including: 1- Control  or basal diets (100% of supplemented Lys from Lys-HCl), 2- Ration 25:75 (75% of supplemented Lys from Lys-HCl and 25% from BioLys-Sulfate), 3- Ration 50:50 (50% of supplemented Lys from Lys-HCl and 50% from BioLys-Sulfate), 4- Ration 75:25 (25% of supplemented Lys from Lys-HCl and 75% from BioLys-Sulfate) and 5- Ration 100 (100% of supplemented Lys from BioLys-Sulfate). Feed ingredients (i.e., corn, corn gluten meal, and soybean meal) were analyzed for amino acid by NIRS in Evonik company representative in IRAN. The composition of basal diet and nutrient composition of feed ingredients. During the study, feed intake (FI) and body weight (BW) were determined at the end of starter, grower and finisher periods, and mortality-corrected FCR was calculated by accordingly. European production efficiency factor (EPEF) was calculated as: EPEF = [Viability (%) × BW (kg) / age (d) × FCR (kg feed/kg gain)] × 100.All the birds were vaccinated intramuscularly through breast muscle with killed Newcastle disease and influenza vaccine (Cevac: New Flu-Kem) at 7 d of age, and Newcastle disease La Sota vaccine was used in the drinking water for vaccination at 14 d of age. Antibody titer against Newcastle disease, avian influenza and sheep red blood cell were detected. At the end of the experiment (42 d of age), 2 blood samples from the wing vein of 2 birds (almost near to mean body weight of each pen) were collected and blood metabolites like serum glucose, triacylglycerol, total cholesterol, albumin, uric acid and creatinine were detected. The other blood sample was used to detecting heterophil and lymphocyte percentages and heterophil to lymphocyte ratio accordingly. Finally 1 broiler from each replicate were selected and slathered, then tibia bone parameters like height, width, diameter, Ca and P percentage were detected. 

The results showed that from 1-42 d, broiler chickens fed the 100-diet had higher feed intake and body weight gain as compared to control group (P < 0.05). Dietary treatments had no effects on serum cholesterol, glucose and uric acid concentrations, spleen and thymus relative weight, heterophil and lymphocyte percentages and heterophil to lymphocyte ratio (H:L), antibody titter against SRBC and New-Castle diseases, tibia bone diameter and width, dry matter and ash percentages (P > 0.05). As compared to control group, broiler chickens fed diet containing 100% BioLys had higher serum total protein concentration, antibody titter against avian influenza and bone Ca and P percentages, tibia bone length, width and index (P < 0.05).

In conclusion, inclusion of BioLys-Sulfate rather than L-Lysine-HCl to broiler chickens diet, increased broiler chickens feed intake and improved immune response and bone parameters but had no effect on broiler chickens body weight. In spite of cheaper cost of BioLys-Sulfate, its inclusion in broiler chickens diet decreased income over feed cost ratio and its use is not economically advisable.

 Obviously, the recent decades strategy in cancer therapy, anticancer drug discovery and drug improvement is to characterize, distinguish and validate the most promising cancer-related molecular targets to which new drugs can be designed. The unique features of the pancreatic RNase (RNase A) such as high activity, stability, lack of a cofactor, and small molecular size have made it the most popular enzyme in the ribonuclease family. Specifically, RNase A is involved in endonucleolytic cleavage of 3'-phosphomononucleotides and 3'- phosphooligonucleotides ending in C-P or U-P with 2', 3’- cyclic phosphate intermediates. RNase A was purified from the Bovidae family including bovine, ovine, bison, eland, goat and gnu. Although phylogenetic analyses of RNase A revealed high similarity among members of the Bovidae family, some functional mutations were also found.Several studies showed that the RNA hydrolyzing action of ribonuclease is able to induce apoptosis and cell death in cancer cells, independently. This effect could be enhanced thousands of times when ribonuclease is linked to antibodies. These enzymes show potent cytotoxic activity on cell internalization but do not show sensible immunogenicity or non-specific toxicity toward normal cells. Ovine pancreatic ribonuclease enzyme is a member of super family RNase A, it can be a good candidate as a toxin for designing new drugs. The objective of this study was to produce ovine pancreatic ribonuclease enzyme in E. coli and characterize its activity.

All structures needed for this study were downloaded from the Protein Data Bank (PDB) website (http://www.rcsb.org/). PDB files (accession numbers: 10.2210 /pdb1YV6/pdb and 10.2210/pdb3SNF/pdb) related to natural Bovine Pancreatic RNase were selected. Gene synthesis and production of recombinant protein were conducted by using the pelB signal sequence at the beginning of the structure for periplasmic protein production. The native ovine RNase and bovine RNase A were optimized for E. coli host by GenRay codon optimization service and sent to GenRay Biotechnology (Shanghai, China) for synthesis. The target genes in pGH vector were sub-cloned in pUC19 and then cloned into the pET21b (+) vector between XbaI and HindIII sites. After transformation, E. coli cells containing recombinant pET21b (+) were cultivated in LB broth medium containing ampicillin. To extract the proteins, osmotic shock methods were applied. After that Q-sepharose chromatography was used to extract the target protein. Finally, Bradford analysis was used to determine the protein concentration. The ribonucleolytic activity of the recombinant native ovine RNase A was compared with native bovine RNase A following Tripathy et al (2013) method. To investigate the antitumor activity of recombinant proteins, HeLa cells were prepared for seeding in a 96-well flask and incubated at 37°C in 5% CO2 for 72 h.

 The production of native ovine and bovine RNase A was confirmed by SDS PAGE. Protein purification was successfully performed using osmotic shock in the Q-Sepharose column. Although our findings confirmed protein expression, no detectable proteins other than RNase A was observed in the LB medium, indicating that almost all the proteins were expressed either inside the bacterial cell or secreted into the periplasmic area. According to the Bradford analysis, the concentration of the recombinant proteins extracted was 4.78 ovine RNase A. Based on our results, it was shown that the ribonucleolytic activity of native ovine RNase A was 558±22. The results showed that RNase A exhibited resistance to pepsin degradation during the whole incubation process (22 h), in the course of which 90% of RNase A remained undamaged. To determine the cytotoxic effect of ovine RNase on the HeLa cell line, MTT assay was done following incubation with ovine RNase A. The commercial RNase A was used as control. The results showed that ovine RNase A and bovine RNase A had no cytotoxic effect on HeLa cells. When RNase treatment was done by the lipofectamine 3000 (Thermo, USA), the cytotoxicity effect was observed. Several studies have shown that some ribonucleases such as onconase, bovine seminal ribonuclease and bovine pancreatic ribonuclease have a great promise as cancer immunotherapeutic agents and cause a significant reduction in the protein synthesis of tumor cells after internalization into cytosol. 

 Our findings demonstrate that ovine RNase similar to bovine RNase has a great potential for use in drug design industry. We revealed that the native ovine RNase A was more stable than the native bovine RNase. In future work, we intend to fuse the engineered ovine-RNase A to dedicated recombinant antibodies for cancer therapy and investigation of engineered immuno-ribonuclease potency and cell killing effects as a fusion protein.

Growth, defined as changes of body weight over time, is an economically important trait in sheep that directly determines meat production.Increase in live weight or dimension against age has been described as growth. Changes in live weight or dimension for a period of time are explained by the growth curves. Animal breeders are interested in the genotypic and phenotypic relationships during all phases of growth. Knowledge of genotypic and phenotypic relationships among live weights, degree of maturity and growth rate during all phases of growth is necessary to formulate breeding programs to improve lifetime efficiency.  Growth models are mathematical functions which are applied for describing the growth pattern. Understanding, estimating, and capturing the defining characteristics of growth processes are key components of developmental research. The aim of the present study was to estimate the genetic parameters for growth traits in Zandi sheep, by determining the most appropriate animal models to be fitted. In addition, genetic, phenotypic and environmental correlations between traits were estimated.

The data used in this study were obtained from the Animal Breeding Center of Iran. The data were screened several times to remove the defective and out of range records. Growth curve parameters used in study were asymptomatic mature weight (A), Growth rate (B) and maturity rate (K). The procedure of SAS software was used for studying of fix effects. Based on body weight at different ages and using different initial values, each of the growth curve parameters was estimated using SAS software version 9.1 and NLIN procedure. Estimation of (co)variance components of growth curve parameters was conducted using Bayesian approach implemented in MTGSAM and Wombat software. The number of Gibbs sampling rounds used was 200,000 rounds.  Ten percent of these numbers (20,000 rounds) was burn-in. The convergence criterion for stopping repetitions in this analysis was also considered as 10 decimals (10-10). Sampling intervals of 200 and Gouss- Seidel 10000 repetitions were considered. In order to find the best model incorporating the constant and random effects affecting each of the parameters of the growth pattern, the following models, with and without regard to maternal effects including maternal additive genetic effects and permanent maternal environmental effects in the model (Meyer’s models) were tested.

 Environmental factors such as year of birth and sex of lamb showed significant influence on growth curve parameters (A, B and k) in Zandi sheep. Estimates of direct heritability is based on best models using REML and Bayesian methods for A, B and K were 0.064 and 0.14, 0.17and 0.16, 0.16and 0.18 respectively. Maternal heritability was in range of 0.006 - 0.08 and Proportion of environmental variance to phenotypic variance in range of 0.03 - 0.05 parameters growth curve. Among the growth curve parameters, only A and k have biological interpretation and therefore, relationship between them may provide necessary conclusions. Estimates of direct genetic correlation between growth curve parameters were 0.323, -0.429 and 0.803 between A-B, A-K and B-K, respectively. The positive and high genetic correlation between A and B parameters is evident as expected for common genetic and physiological mechanisms controlling these traits. Positive genetic correlation between these traits suggests that selection in one parameter of the growth curve would also improve the other parameter. Residual correlations between growth curve parameters varied form −0.296 (between A-K) to 0.732 (between B-K). Phenotypic correlations between growth curve parameters varied form −0.184 (between A-K) to 0.743 (between B-K). The phenotypic and genetic antagonism between A and k indicates that rapid reduction in growth rate after inflexion point results in lower mature weights. This finding would be helpful for improving selection by identifying the animal who reaches inflexion point earlier and attend higher mature weights later.

 Current genetic estimates for growth curve parameters in Zandi sheep could be applied in designing selection program in this breed. The low estimates of heritability for A, B and K parameters could be assigned to the high phenotypic variance arising from large environmental variation. This therefore implies that much of the improvement in these growth curve parameters could be obtained by improvement of environment rather than genetic selection. It is important to provide good environmental conditions along with optimal management strategies in the flock to achieve a desired shape of growth curve through changing the parameters of model.

Development of high-power and cost-effective genotyping methods in recent years has provided the possibility of evaluation the genetic structure and the relationship among species populations utilizing genomic data. Genome wide inference of population structure using genetic markers could provide invaluable information associated with evolutionary relationships and clustering of subpopulations for performing animal breeding programs. In large scale studies, one of the interesting subjects is to study the existence of genetic differences among subdivided groups ascertained from different geographic locations. The objective of this study was to compare the principal component analysis (PCA) and discriminant analysis of principal component (DAPC) approaches for determining the population structure and study how an individual allocated to the true population of origin, in three Horse breeds located in Middle East consisting Akhal Take, Arabian and Caspian using genomic data.

 In this study, the genomic data obtained from 61 animals consisting Akhal Take (19), Arabian (24) and Caspian (18) were used to investigate the population structure of some Asian horse breeds. The data were obtained from the Equine Genetic Diversity Consortium (EGDC) project. Hair or tissue samples were collected from animals. DNA extraction was performed using an optimized Pure gene (Qiagen) assay and approximately 1 μg of DNA was used for genotyping of the samples. Genotyping was performed using Illumina SNP 50K BeadChip arrays that allow to genotype 52603 SNP marker loci, according to the Illumina standard guidelines. In this study, different quality control steps were applied on preliminary data to ensure the quality of genotyping data. Quality control carried out using PLINK v.1.07 program. The samples with more than 5% missing data were excluded from analysis. Then for each SNP, MAF and call percentage were calculated and the SNPs with a call rate<95% and a MAF<2% were discarded. Deviation from Hardy-Weinberg equilibrium (p<10-6) was estimated for the remaining SNPs to identify genotyping errors. The Bonferroni correction (β=α/n) was used to address the multiple testing comparison problem. Principal component analysis (PCA) is a statistical technique for summarizing data from many variables into a few variables which describe as much of the variation in the data as possible. For this purpose, the variance-covariance matrix of independent variables was first calculated and principal components were extracted. Each new variable has an associated Eigen value that measures the respective amount of explained variance. Furthermore, the model independent of discriminant analysis of principal component (DAPC) is a multivariate method designed to identify and describe clusters of genetically related individuals. When group priors are lacking, DAPC uses sequential K-means and model selection to infer genetic clusters. Analysis was performed using PCA and DAPC approaches and the codes for analysis were provided in R v.3.4.1 software.

The analysis of the main components summarizes the general variation among individuals, which includes both the variability between the groups and the diversity of the groups, and shows a clear picture of the differences between the groups. The results of this study indicated that 10.8% of the variance was explained by the first two components in both PCA and DAPC methods. Both methods showed high accuracy for assigning of individuals to the true population of origin and both were able to cluster three populations separately. The Bayesian information criterion (BIC) index was used for evaluating the optimal number of clusters for DAPC method and the results revealed that K=3 showing the optimal number with lowest BIC that completely separate three populations. The DAPC method was better than PCA to separate populations from each other due to the increase of intergroup variance and the reduction of intra-group variance. In determining the optimal number of K, it worked better than PCA method and provided a better picture of the relationship between individuals. This results show that DAPC method can be applied in quality control of GWAS as an alternative to the PCA, because of summarizing the genetic differentiation between groups and overlooking within-group variation and provides better population structure.

 In general, the results of this study showed that although the previous studies grouped these three breeds located in Middle East in one cluster of neighboring trees, however, according to the results of this study, three breeds are grouped separately, and the DAPC method can better illustrate the inter-population relationships in horse breeds.

 Introducing new commercial lines is one of the goals of silkworm breeding centers in the world. Iran has the potential to introduce new lines for hybrid silkworm production due to its silkworm genetic resources and silkworm egg production technology. The performance of productive, reproductive and viability traits in the parental silkworms, including Japanese-shaped and Chinese-shaped lines, changes after several years for various reasons, including inbreeding. Therefore, after a few years, it is necessary to introduce new silkworm strains. Most silkworm breeding schemes in most of the countries are based on the introduction of the Chinese and Japanese-shaped lines to make commercial silkworm hybrid.

 Five Japanese - shape lines of silkworms named 31, 103, 151, 153, and 1524 were selected from silkworm germplasm of Iran Silk Research Center in the spring of 2012. All genetic combinations obtained by using the diallel method of mating system (20 crosses) were reared in autumn 2012 and spring 2013. After two generations of mass rearing in each genetic combination, the reciprocal crosses in the diallel design were mixed to establish the basic generation of this breeding scheme. The selection program was based on independent culling levels (I.C.L.) method applied from 2014 to 2019 in the selected group. At the same time, all parental lines were reared as control by using a random mating system. Of the 10 genetic compounds, six combinations were retained and the rest were rejected. In this breeding program, due to the necessity of eliminating weak families, family selection, and individual selection were both used simultaneously. In the present study, the productive traits of cocoon weight, cocoon shell percentage, good cocoon percentage, number of cocoons per liter, and cocoon weight per liter were compared simultaneously in the genetic combinations and control lines. Two-factor analysis of variance (including 6 genotypes and 5 years) was performed in a completely randomized design with six replications; then the results were analyzed using SAS statistical software.

In general, the effects of genotype, year and interaction effect of genotype and year were significant for all studied traits. Based on the average performance of each trait during selection program from 2016 to 2019 years (average performance of G2, G3, G4 and G5 generations), the cocoon weight in the combinations of IRA1, IRA11 and IRA7 was more than the parental lines. This advantage was also seen in the trait of cocoon weight per liter. For the cocoon shell percentage, none of the genetic combinations in all the studied years were completely superior to parents. The response to selection for cocoon weight based on deviation from the maternal control line in IRA5 and IRA1 was positive and significant. The two genetic compounds, IRA1 and IRA3, whose parent was 103, had the highest genetic progression for cocoon shell percentage. Due to the superiority of the good cocoons percentage in IRA1, this genetic combination performed well in terms of cocoon economic traits. IRA9, whose cocoon weight gain was lower than the others, not only did not show any improvement in cocoon shell weight compared to the parent during these years, but also showed the lowest amount compared to other genetic combinations.

 The six new genetic compounds in this breeding program had the minimum requirements for the economically important traits of the silkworm. In other words, cocoon-related characteristics such as cocoon weight, good cocoon percentage of each family, and cocoon size are superior to all parental lines, then they could introduce to the silkworm gene bank. IRA1 was superior to parents in most of the studied traits. This genetic combination showed the best performance compared to the parent for both cocoon weight and cocoon shell percentage. Therefore it can be considered more in subsequent evaluations. IRA3 also responded relatively well. Other new genetic combinations did not have a significant advantage over their parents in terms of cocoon shell percentage. However, lower performance in some traits is not a reason for the new strain to be undesirable. Because the selection of the best paternal and maternal lines (Chinese-shaped and Japanese-shaped lines) will be determined after that the hybridization program was carried out to produce all hybrids and then the best hybrids were selected based on  estimation of specific combining ability for all important traits.