مجله پژوهش در نشخوار کنندگان
سال هشتم شماره 1 (بهار 1399)

Bovine diarrhea is a common disease among calves that causes significant economic losses in the dairy and meat industry because of increased mortality, treatment costs and reduced growth rates and increasing age at first calving. Bovine rotavirus is one of the main causes of diarrhea in calves at the age of one to two weeks. Both vp4 and vp7 proteins form the outer capsid of the virus, producing antibodies and stimulating the immune system. Camel lactoferrampine-Lactoferrin is a potent antiviral that binds to heparin proteoglycine sulfate, prevents virus entry into the host cell and can replace antiviral drugs. The aim of this study was to investigate the possibility of replacement of camel lactoferrin peptide with antiviral drugs.

In this study, the possibility of replacing six recombinant camel lactoferrin peptides named clf36-1, clf36-2, 12A-36F + BC, A_Scaning, AF, Arm with antiviral drugs and efficient binding of these peptides to Surface proteins of bovine rotavirus (vp4 and vp7) was investigated by molecular dynamics simulation using GROMACS software and they were compared due to their bond-dissociation energy in docking step and amount of electric charge before Neutralizing the electric charge of systems in molecular dynamics and finally the best substituted peptide was selected according to Radius of gyration diagram which is the main determinative factor in system efficiency in vivo and also indicates the possibility of stable binding of recombinant lactoferrin peptide to the virus’ surface protein.

The results of this study indicate that the lactoferrin peptide binds well with the rotavirus’ surface proteins and can thus prevent the virus from entering the cells. However, among the six peptides examined, the 12A-36F + BC peptide in both vp4 and vp7 systems seems to be inefficient in vivo in spite of the highest bond-dissociation energy and the most positive electric charge before Neutralizing the electric charge of systems in molecular dynamics. As being unfold and Rg fluctuation during the simulation. Hence this study expects that recombinant peptide clf36-1 and vp4 system will bind well according to the Radius of gyration diagram.

The results of this study show that the clf36-1 peptide was stable and efficiently bound to vp4 surface protein among the six peptides investigated while retaining its structure during the simulation and in this way it can prevent the virus from entering the cells. So it can be an appropriate alternative to antiviral drugs. However, in vivo experiments are needed to prove the efficacy of this peptide.

Improvement of the quality of animal products by new scientific and practical methods is one of the important goals of animal nutritionists. Rearing systems based on low access to pasture decrease the useful fatty acids in animal products. Several studies have been shown that feeding strategies are known as the most effective factor on alteration of fatty acid composition of muscle and fatty tissues in ruminants. Therefore, this study aimed to assess the influence of Pomegranate seed oil (PSO) with higher ratio of unsaturated fatty acids, steroidal and polyphenolic compounds on blood metabolites and fatty acid profiles in bicepsfemoris muscles in the fattening lambs.

Twenty one male Sanjabi lambs (BW=27.5±2.6 kg, 3-4 months old) were used to evaluate the effects of PSO supplementation on blood parameters and fatty acid pattern of bicepsfemoris muscle. Lambs were randomly distributed between three treatments (control, and diets containing 2 and 4% of PSO) and were fed adlibitum for 90 days. The experimental diets were formulated (DM basis) to be isonitrogenous (CP=14.7%) and isocaloric (ME=2.6 Mcal/kgDM) and to meet NRC (2001) .Blood samples were taken from each lamb (10 ml) at the end of first, second, and third months and metabolite parameters concentration in blood were measured. Samples of Bicepsfemoris muscle were dissected and homogenized for determination of fatty acid composition to the procedure described by Folch et al. (1957). Fatty acid derivatives were prepared by methylation of the fatty acids (Metcalfe and Schmitz, 1961). The pattern of Fatty acids were determined by using gas chromatography apparatus (17, 37). This study was based on completely randomized design. Data were analyzed statistically by general linear model (GLM) procedure and means comparing were done by Duncan's multi-domain test with SAS (2004) software version 9.1 (51).

Results show that concentration of AST, ALT and ALP, insulin, uric acid and creatinine, were not affected by different levels of PSO in diet. No significant difference was observed in the amount of palmitic, stearic, myristic, linoleic acid (C18: 2) and linolenic acid (C18: 3) in bicepsfemoris muscle. Addition of PSO at level of 4% decreased (P <0.05) the MUFA level compared to control (47.69 vs. 39.08). Mean PUFA and PUFA to SFA ratio in bicepsfemoris muscle of lambs received PSO were higher than those in the control group (2.3 and 2.2 times, respectively). However, these differences were not significantly different. Total amount of omega-3 fatty acids (PUFA n-3) significantly increased due to feeding PSO.

Due to positive trend observed in MUFA, n-3 fatty acids and PUFA: SFA ratio, with increasing the levels of PSO, addition 4% of this oil in the diet of fattening lambs is recommended.

This study was conducted to evaluate the effect of milk supplementation (Roumak Extra) on performance of infant Holstein calves. Roumak Extra supplement was prepared from Soha Aghrin Tech Co. which consists of vitamins (water soluble and fat soluble), Micro minerals and probiotics. The average birth weight of calves was 36.76 ± 5.80 kg. Each treatment consisted of 10 calves which were examined in individual boxes for 60 days (4 periods of 15-day). This research was carried out in a completely randomized design with three treatments as follows: 1-control treatment without supplementation of Roumak Extra 2- Treatment A by adding15 grams Roumak Extra supplement per liter of milk 3- Treatment B with the addition of 25 grams Roumak Extra supplement per liter of milk. Whole milk was fed to calves at two meal at 900 and 1700. Starter were identical in terms of crude protein (%20) and Metabolizable energy (3.3 Mcal/kg). Calves had free access to starter and water from the beginning of the plan. All data were analyzed by Mixed procedures of SAS software. Body weight changes and daily gain were not significant between the supplemental calves and the control group (P˃0.05). Consumption of starter was significantly higher in control group when compared with supplement recieved treatments (P<0.05). Dry matter digestibility increased in supplemented treatments when compared to control group (P<0.05). However, feed conversion ratio were improved in supplemented treatments (P<0.05). Roumak Extra supplementation has no significant effect on water and straw consumption time (P˃0.05). However, here is no significant difference between treatments in terms of lying, standing and ruminating time (P˃0.05). However, the time of starter consumption was higher in control group when compared with supplemented treatments (P<0.05). Blood concentration of albumin, glucose and betahydroxybutyrate were not affected by supplementation (P˃0.05). But, blood total protein and urea concentration was higher in control group when compared with supplement received calves. The effect of vitamin and mineral supplementation of Roumak Extra on the growth of the skeletal system (round the chest, widther height and loin height) was also were not significant between treatments (P˃0.05). In general, despite the decrease in feed intake and the time spent on it in supplement received calves in this experiment, due to higher dry matter digestibility and improvement in feed conversion ratio, the final weight and daily weight gain of the receiving calves on supplemented were same as control group representing an improvement in calves' performance.

According to an increasing interest for using artificial insemination by sheep producers, finding methods to maintain frozen semen fertility would be important and applicable. One of the freezing semen disadvantages is increasing of free radicals led to enhanced sperm membrane peroxidation then consequently causes lowered semen fertility after thawing. Some plants bearing high levels of plant antioxidants can help to decrease semen peroxidation. Cysteine, in addition, is a precursor of glutathione peroxidase being the most important antioxidant property in semen. Therefore, the aim of the study was to investigate the effect of adding different levels of ethanol extract of Mentha Longifolia (0, 100 and 200 microL/ml) and cysteine (0, 5 and 10 mmol/l) into ram semen on fertility features after freezing and thawing processes.

In the study, semen samples were collected from four mature, fertile Baluchi rams (> 2y-old) by artificial vagina and after initial evaluation were pooled together. Then, samples were extended in an extender based on Tris-egg yolk. Treatments were arranged as a 3×3 factorial experiment including nine treatments and six straws were assigned to each as replicate. After treating, the straws were filled by the equal amount of semen and after chilling in refrigerator (4 °C) for two hours were frozen in liquid nitrogen container. After thawing the straws at day 10, sperm motility parameters were assayed by CASA. Furthermore, the percentages of viability, plasma membrane integrity and normal morphology of sperms were evaluated by microscope. Data were analyzed by SAS software using GLM procedure and the means comparison was performed by Tukey-Kramer test at 5% error.

Results of the study showed that the effects of adding horsemint extract and cysteine into the extender and the interaction between them on the all motility and viability parameters of frozen ram sperm after thawing were significant (p<0.05), exempt for sperm morphology where only the effect of adding cysteine was significant. Means comparison showed that the greatest sperm total motility, plasma membrane integrity, linearity and curvilinear velocity were observed in cysteine10 treatment (without horsemint extract), while the greatest sperm viability, straight line velocity and average path velocity were seen in cysteine5 treatment (without horsemint extract). The greatest sperm progressive motility percentage was observed in horsemint200 group (without cysteine).

In general, considering to the beneficial effect of adding cysteine into the extender based on tris- egg yolk on the most of fertility parameters of ram frozen semen after thawing, using levels of 5 and 10 mmol cysteine per ml extender in order to maintain fertility of frozen ram semen is recommended.

Dietary fat has been shown to improve reproductive performance and lactation. Therefore, this experiment was conducted to investigate the effects of adding cotton and canola to Kurdish ewes' diet on the ability to digest the nutrients, some metabolites and blood hormones were carried out after birth.

The design was carried out in a completely random design. Treatments included 1) diet without oilseed 2) diet containing 6% cotton dry matter 3) diet containing 6% cotton dry matter 4) diet containing 3% f cotton and 3% cotton dry matter. Feed digestibility was calculated according to the method of Wankulen and Young (1977). Blood samples were taken at 5, 3 and 1 weeks after calving to assess blood metabolites and hormones. rumen fluid was obtained by oral sucker.

The results showed that the effect of treatments on ruminal pH was significant at 5% level, with the highest pH related to canola seed treatment (6.60). Blood glucose levels were significantly increased in all treatments (1, 3 and 5 weeks) in treatments containing oilseed (P <0.01). The highest amount of glucose was related to canola seed treatment in the 5 week of calving (90.90 mg / dl). Blood cholesterol levels in all three treatments were significantly increased in treatments containing oilseed, and the highest cholesterol level was observed in the cotton and canola (85 mg/dl) treatment one week after calving (P <0.01). Insulin levels were significantly increased in canola treatment at week 3 and 5 (P <0.01). Among the digestibility factors, dry matter increased in treatments containing oilseed, and the highest dry matter was in cotton and canola (54.42) (P <0.05). NDF was significantly decreased in treatments containing oilseed and the lowest NDF was in canola seed treatment (45.52) (P <0.05).

The overall results of this study showed that the use of oilseeds improved digestibility and it has had a positive effect on blood cells. Therefore, it is recommended to use a diet containing 3% dry matter cotton and 3% canola dry matter in postpartum period.

The overall results of this study showed that the use of oilseeds improved digestibility and it has had a positive effect on blood cells. Therefore, it is recommended to use a diet containing 3% dry matter cotton and 3% canola dry matter in postpartum period.

The overall results of this study showed that the use of oilseeds improved digestibility and it has had a positive effect on blood cells. Therefore, it is recommended to use a diet containing 3% dry matter cotton and 3% canola dry matter in postpartum period

Antibiotics have long been widely used to stimulate growth and prevent disease in animals. But, concerns about bacterial resistance and gastrointestinal malformations have prompted nutritionists to look for alternatives. Probiotics and ruminal growth promoter are among them. Probiotics are viable microorganisms that their use by ruminants has beneficial effects on the growth and microbial population balance of the rumen and will improve animal performance by improving feed conversion ratio. Calves are exposed to a variety of stressful events at birth due to defects in the immune system and underdevelopment of the digestive tract. Because of this, stimulation of rumen development, microbial population balance, and transfer of calves from the single gastric to the ruminant state are necessary. This study was conducted in order to investigate the effect of probiotic additive and ruminal growth promoter on feed intake, weight gain, skeletal growth indices, health, and blood metabolites of young dairy calves.

in this study, twenty four Holstein female calves immediately after birth, were used in a completely randomized design (4 treatments and 6 replicates). Calves after birth were randomly assigned into one of four treatments as follow: 1) control (milk without any probiotic or ruminal growth promoter), 2) calves receiving probiotic additive, 3) calves receiving or ruminal growth promoter and 4) calves receiving probiotic additive + ruminal growth promoter. Measurement of dry matter intake and fecal scoring were done daily. Calves were weighed once every15 days. Blood smples were taken at 21 and 45 days of age, 3 hours after morning feeding. Ruminal fluid was collected 4 hours after morning feeding on days 21 and 45 to measure pH and ammoniacal nitrogen. Skeletal growth indices were measured every 15 days up to 90 days. The data obtained from this study were analyzed according to completely randomized design and repeated measurements.

Results showed that probiotic and ruminal growth promoter supplementation had no significant effect on body weight, body weight gain changes and average body weight gain (P>0.05). There was no significant difference between control calves and those fed with probiotic and ruminal growth promoter in terms of skeletal growth indices (P>0.05). Fecal consistency score was higher in control than other treatments (P<0.05). Probiotic and ruminal growth promoter supplementation decreased ammoniacal nitrogen concentration on days of 21 and 45 (P<0.05). Treatments had no significant effect on blood concentration of glucose, cholesterol, urea and BHBA (P>0.05). However, concentration of triglyceride, total protein and albumin was different among the treatments (P<0.05).

Totally, The results of this study showed that Probiotic and ruminal growth promoter supplementation had no noticeable effect on the studied traits.

The largest expense in the livestock industry is related to feed costs, which accounts for about 70-60% of all current costs. Utilizing new sources of energy and protein can help reduce these costs. Therefore, the aim of this study was to investigate the performance and digestibility of lambs Dalagh and crossbred of Romanov- Dalagh lambs by replacing pea seed with barley and soybean meal in ratio.

This experiment was conducted in a completely randomized design with 3 × 2 factorial arrangement with three types of diets including 0, 10 and 20% pea seed and two breeds of Dalagh and crossbred of Romanov-Dalagh. In order to implement the design were used from 15 Dalagh and crossbred of Dalagh-Romanov lambs with an average weight of 5: 30.66 ± 2.30 and 24.2 ± 1.5 kg that were kept individually for 84 days (plus 15 days of habitually). Weighning and feed intake was carried out and the finally were evaluated the carcass and the digestibility of feed for each treatments. All statistical analyzes were performed in mixed regression (Proc Mixed) in SAS software version 9/1.

There was no significant difference between treatments for weight gain (P> 0.05). In pure Dalagh, control and 20% pea treatments, with 294 and 265 grams per day had the highest and lowest daily weight gain respectively. In Dalagh breed, the lowest and the highest final weights were in pea and control treatments with a mean of 49.5 and 52.6 kg (P> 0.05). Also, in crossbred Romanov-Dalagh, the highest and lowest daily gain was observed in pea and control group with a mean of 294 and 288 g /day, respectively (P> 0.05). The average daily gain in two breeds in the control, 10 and 20 % of the pea treatments, were 299.5, 27.3 and 798.8 grams, respectively. The digestibility of feed in three treatments did not differ significantly. Percentage and carcass weight in Dalagh breed decreased with increase in pea in feed, unlike in crossbred Romanov-Dalagh.

The use of chickpea seed instead of soybeans and barley did not decrease fattening performance; In addition, the digestibility was almost the same as the control group. Fattening performance and digestibility of feed in crossbred Romanov-Dalagh was better than that of pure Dalagh. In general, it can be said that the replacement of chickpea seeds with existing import restrictions can help to significantly contribute to the sheep's fattening industry.

Wheat straw (WS) has low nutritional value; however, because of simple availability as well as its low price rather than other forage sources has high consumption in lamb production. Different methods such as chemical processing for WS has been suggested that could be have some health concerns for both producer and animal. The other strategy is to improve fiber digestion of low quality forages with balanced nitrogen sources in diet. Greater rumen undegradable protein (RUP) level in diet of ruminansts those fed low quality forages caused greater efficiency. Therefore, in the present study we evaluated the effects of different ratios of RUP: RDP in sheep fed with high level of WS (400 g/d) on fermentation parameters, nutrients digestibility, blood metabolites, and purine derivatives excreted through urine.

The study was carried out on three ruminal fistulated sheep in 3 × 3 Latin square design with 21-d periods (the first 14-d for adaptation period and the last 7-d for sample collection). The treatments were; (1) LR; low RUP: RDP ratio (30:70); (2) MR; medium RUP: RDP ratio (35:65) (3) HR: high RUP: RDP ratio (40: 60). For RUP modification in diet and having different RUP: RDP ratios, processed soybean meal was replaced with soybean meal. The basal diet contained high amount of WS (400 g/kg, DM basis) as low quality forage. Ruminal fermentation pattern, microbial protein synthesis, nutrients digestibility, blood metabolites and urinary purine derivatives were evaluated in the current study.

The results show that the intake did not differed among treatments (P > 0.05). The concentration of short chain fatty acids (SCFA) was constant among treatments; however, acetate concentration (P = 0.05) as well as branched chain volatile fatty acid (BCVFA) concentrations (P = 0.04) were greater in LR diet. The greatest ruminal ammonia nitrogen was obtained for LR diet as well. Neutral detergent fiber digestibility was the greatest value for LR diet among treatments (P = 0.04). There was no significantly different for another nutrients digestibility. Considering blood metabolites, HR diet reduced blood urea nitrogen. But there was no other effect of treatments. The liver enzymes (AST and ALT) did not differed among treatments. The urinary excretion of allantoin (P = 0.03) was increased in HR diet and subsequently purine derivatives excretion (P = 0.04) was improved in this diet. Urinary urea nitrogen (UUN) (P = 0.05) concentration was reduced in HR diet that was a greater nitrogen efficiency.

The present study results show that the high level of RUP: RDP (40:60) caused increased MPY and reduced UUN. In conclusion lower level of RUP: RDP improved digestibility, but from the nitrogen efficiency perspective, the greater RUP: RDP could be recommendable in diets high in wheat straw as low quality forage.