نشریه علوم دامی (پژوهش و سازندگی)
پیاپی 141 (زمستان 1402)

This study was conducted to evaluate the effect of different levels of probiotic yeast supplement (Saccharomyces servicii) in the diet on growth performance, carcass traits, and some blood and rumen parameters in Zell cross-breed fattening lambs. For this purpose, a total of 24 crossbred of Zell-Atabai lambs with a mean weight of 26±2 kg and a mean age of 5.5 months were used in a completely randomized design with 4 treatments and 6 replications for 90 days. The results of growth performance showed that the treatment with 8 grams of probiotic supplement significantly had the highest final fattening weight, daily weight gain and the lowest feed conversion ratio (P<0.05). In apparent digestibility of nutrients, treatment with 8 grams of probiotic supplement had the highest digestibility of crude protein and NDF (P<0.05). In the results of blood parameters, there was a significant difference in the concentration of glucose, cholesterol and HDL between experimental treatments (P<0.05). The results of carcass traits showed that in live weight, thigh percentage and shoulder percentage, treatment with 8 grams of probiotic supplement significantly had the highest values (P<0.05). The highest value of pH, VFA, acetic acid, propionic acid, total population of bacteria and ruminal fluid protozoa was observed respectively in the treatment of 8 grams of probiotic supplement (P<0.05). The general result of the research showed that the consumption of 8 grams of yeast probiotic supplement improved growth performance, valuable carcass parts, apparent digestibility and morphological characteristics of rumen villi in fattening lambs.

The aim of this research was to evaluate the effects of different levels of camelina sativa meal (CSM) (native variety of Soheil) on nutrients intake, growth performance and apparent nutrient digestibility of Lori-Bakhtiari fattening lambs. A total of 30 fattening lambs with average age of 4 to 5 month (average live weight of 34.5 ± 5.0 kg) were used in a completely randomized design with 3 treatments and 10 replications for 56 days. Experimental diets were replacing soybean meal with CSM at levels 0 (control), 5 and 10% diet of dry mater (DM). The results showed that by increasing the level of the CSM in the diet up to 10%, except fot ether extract consumption which increased linearly (P <0.05), intake of other nutrients including DM, organic matter (OM), crude protein (CP), neurtal detergent fiber (NDF) and acid detergent fiber (ADF) were similar among experimental diets (P >0.05). In term of performance traits, final body weight, total weight gain, average daily gain and feed conversion ratio were unchanged during the entire fattening period and once every two weeks by feeding experimental diets (P >0.05). Also, experimental diets did not affect nutrients digestibility of DM, OM, CP, NDF and ADF (P >0.05). In general, the results of the present study showed that the use of native variety of camelina meal instead of soybean meal as a new protein source is recommended up to 10% in fattening lambs diet.

In order to investigate the effects of growth and immunity-stimulating additives based on medicinal plants with and without probiotics on the performance and physiological and metabolic parameters of broiler chickens, an experiment was conducted in a completely randomized design (factorial arrangment) with three types of additives (commercial Bioherbal additive, ASRI-I1 and ASRI-I2) and two levels of Gallipro probiotics (0, 200 g/ton), in 6 treatments and 4 repetitions and 15 pieces of mixed male and female chickens in each repetition.The effects of immune stimulants and probiotics on body weight, feed consumption, food conversion ratio, viability percentage and production index were not significant. Carcass percentage, thigh percentage, breast percentage, back and neck percentage, abdominal cavity fat percentage and relative weight of internal organs were not affected by immune stimulant and probiotic. The effect of herbal and probiotic immune stimulants on the response to sheep red blood cells, immunoglobulin G and immunoglobulin M was not significant.The effect of immune stimulants on the percentage of heterophils, lymphocytes and their ratio was significant (P<0.05). In the whole period, no significant difference was observed in most of the examined traits in broiler chickens fed with diets containing three different types of immune stimulants, but numerically, there were slight differences between them, and the addition of IASRI 1 had better effects. Among other additives, its use along with probiotics showed beneficial effects in improving the performance and immune responses of broiler chickens, therefore, IASRI 1 additive is recommended for additional studies and semi-industrial production.

A study was performed to investigate the effect of rumen protected methionine (RPM) on growth traits and feed efficiency of weaned Holstein calves using 40 calves in 4 experimental groups in a CRD plan with repeated measures were done. The experimental groups were included: 1) control (not given RPM after weaning at 75 days) 2) group was given RPM until 10 days 3) group that was given RPM until 20 days 4) group that was given RPM until 30 days after weaning. RPM was used in the amount of 2 g/d/calf. The studied traits included weight and average daily gain, body length and height, and calculated feed efficiency of experimental period. The results showed that the average feed and nutrient intake (protein and energy) of the third and fourth treatments at the ages of 85, 95 and 105 days were 9.79, 10.12 and 10.27% higher than the average of the first and second treatments (P<0.05). Daily weight gain and feed efficiency of these treatments were also 15.92% and 4.63% respectively (P<0.05).Treatments using methionine supplements had a higher average weight (4.16%) and a higher average height increase (8.15%) than the control (P<0.05). In conclusion, the use of coated methionine supplement in the ration of calves after weaning had a positive effect on growth performance, height measure and overall feed efficiency and it can be recommended at the mentioned level to the farmers. Key words: Body measures, Gain, Feed efficiency, Holstein calves.

In order to investigate the effect of the replacement of different levels of wheat straw with cottonseed plant on performance, activity of hydrolytic enzymes and rumen parameters of Dalagh ewes,18 ewes were used in a completely randomized design with three treatments and six replications. The three experimental treatments in this study were zero, 20 and 40%, respectively, the use of cottonseed plant in the diet. The use of different levels of cottonseed plant in ewes did not cause significant differences in performance, dry matter intake and feed conversion ratio. Experimental treatments had no effect on ruminal pH at three fasting times, three and six hours after feeding in the morning. Rumen ammonia concentration in the diet containing 40% of cotton seed plant was significantly higher than other treatments (P<0.05). There was no significant difference in rumen protozoan population at fasting between treatments receiving different levels of cottonseed plants in the diet. However, the rumen protozoan population at the time of three and six hours after morning feeding in the treatment receiving 40% of cottonseed was significantly higher than other treatments (P<0.05). The activity of carboxymethylcellulase and microcrystalline cellulase enzymes was affected by experimental treatments. The highest activity of carboxymethylcellulase and microcrystalline cellulase was observed in all three sections and the total activity was observed in ewes fed with 40% diet of cottonseed (P<0.05). According to the results, cotton seed plant up to 40% can be used in diets of dilapidated ewes without negatively affecting livestock performance and rumen health.

In the current study, the effects of quinoa seed treating on chemical compounds and anti-nutritional factors by four treatments:1)raw seeds, 2)seeds of soaken in 40ºCwater by ratio of1:10during 24 hours, 3)seeds of soaken in 1%acetic acid solution by ratio of 1:5during 24hours, 4)seeds of soaken in 1%sodium bicarbonate solution by ratio of 1:10during 24hours, in five replications and diets ileal digestibility in 240laying quails by six treatments: 1)corn-soybean meal without quinoa seeds based diet, 2)diet containing 10%raw quinoa seeds, 3)diet containing 10%quinoa seeds of soaken in 40ºC water, 4) diet containing 10% quinoa seeds of soaken in 1% acetic acid solution, 5) diet containing 10% quinoa seeds soaken in 1% sodium bicarbonate solution 6) diet containing 10% raw quinoa seeds supplemented with 0.05% Rovabio multi-enzyme in five replications, and eight birds per replication by a completely randomized design, were investigated. The soaking in 1% acetic acid solution significantly decreased the crude fiber of quinoa seeds (P<0.05). The soaking in 1% sodium bicarbonate solution significantly increased the crude ash and sodium of quinoa seeds (P<0.05). The lowest tannin and trypsin inhibitors in seeds of soaken in water 40ºC and the lowest saponin and phytic acid were in seeds of soaken in 1%acetic acid solution (P<0.05). Treating and enzyme supplementation, significantly increased the ileal digestibility of dry matter, crude protein, crude fat, crude fiber, ash, calcium, and phosphorus of the diet (P<0.05). Soaking quinoa seeds in 1% acetic acid solution by ratio of 1:5 during 24 hours was the best treating method.

In this research, the effect of zinc and selenium synthesized from nano-mineralized probiotics was investigated on yield characteristics, egg quality characteristics, antioxidant status, and immune response of laying hens. A number of 576 high-line laying hens at the peak of production (from 25 to 37 weeks of age in three four-week periods) were used as a completely randomized design with a 3x3 factorial experiment with eight replications and eight birds per replication. Experimental treatments are 1. The control diet (without selenium and zinc), 2. Control diet + selenium chelate, 3. Control diet + zinc chelate, 4. Control diet + zinc synthesized from probiotics, 5. Control diet + selenium synthesized from probiotics, 6. Control diet + zinc chelate + selenium chelate, 7. Diet Control + zinc chelate + selenium synthesized from probiotic, 8. Control diet + zinc synthesized from probiotic + selenium chelate, 9. Control diet + zinc synthesized from probiotic + selenium synthesized from probiotic. The results showed that using zinc and selenium synthesized from probiotics increased production percentage, average egg weight, and improved feed conversion ratio (P<0.05). The serum concentration of cholesterol, triglyceride and malondialdehyde in chickens receiving probiotic zinc and selenium was the lowest. The serum HDL concentration and total antioxidant index were the highest compared to other treatments (P<0.05). In general conclusion, zinc and selenium synthesized from nano-mineralized probiotics have a better performance in laying hens.

Bee venom is widely used in the field of medicine and pharmaceuticals. Several factors are effective in the amount and compounds of venom. So far, no research has been done on the amount of Iranian bee venom compounds. The aim of this study was investigation of the amount of three important peptide compounds (melitin, phospholipaseA2 and apamin) in Iranian honeybee venom. Venom samples were collected from four apiaries located in areas with different (predominant) vegetation. The areas had dominant vegetation of sunflower, various foothills plants, corn and alfalfa. The apiaries were located in that areas for at least two months. Collection of venom was carried out by a standard venom collector device. Samples were sent to the laboratory to measure the three intended peptides. The data were analyzed in a completely randomized design with 4 treatments and 3 replications. The average amount of mellitin, phospholipase A2 and apamin were 40.25 ± 8.37%, 11.66 ± 2.77 and 2.31 ± 0.55%, respectively. The amount of mellitin in second treatment was estimated 52.04%, which was significantly higher than the others. This treatment had the highest amount of phospholipase A2 and apamin too, but this superiority was not statistically significant. It seems that this can be related to the varied and special vegetation in this treatment. This study was done for first time in Iran and it is necessary to conduct more research. If the results are confirmed, Mountainous areas can be introduced as the best areas to produce bee venom with higher quality.

The present study was conducted to investigate the effect of agricultural wastes as a non-fasting method on inducted molting, productive performance, immune response, and blood parameters of laying hens with five experimental treatments and five replicates, including seven birds in each replicate. Dietary treatments consisted of feed withdrawal, apple peel waste, carrot pomace, tomato pomace, and zinc oxide (20 g/kg). The results indicated feed intake in pomace groups decreased significantly (P<0.05). Molting methods did not affect body weight reduction. The zinc group was the lowest egg production in during the molting time, and apple peel waste and tomato pomace groups significantly increased compared to the zinc oxide group in resting time (P<0.05). In days 5 and 11 of molting, heterophil to lymphocyte ratios were significantly lower in the pomace groups than in the feed withdrawal group (P<0.05). Pomace treatments had no significant effect on the egg quality, except for carrot pomace and tomato pomace groups, which increased the yolk color (P<0.05). The lowest level of triglyceride was related to pomaces, the highest levels of cholesterol and MDA were attributed to the feed withdrawal group, and the highest levels of glucose were reported for the tomato pomace, which were statistically significant compared with the control group (P<0.05). Ovary and oviduct weights were significantly lower in the pomace groups than the zinc oxide group (P<0.05). In conclusion, using tomato pomac or apple peel waste as a non-fasting molting method can be an effective alternative to the feed withdrawal method.

In order to compare the performance of neural network with some mathematical functions for predicting of lactation curve of Iranian Holstein dairy cows, a total of 1,085,525 milk test day records from first-parity dairy cows calved during 1983-2012 were used. Fitting the lactation curve was performed by brnn package (for neural network) and also by some mathematical functions (including Wood, Wilmink, Ali-Schaeffer and Pollott-Gootwine) using R software based upon average milk yield, fat and protein percentage test day records. The criteria of AIC, BIC, RMSE and adjusted R2 were utilized to evaluate goodness of fit. The results showed that the Bayesian neural network (brnn) had a better fit than mathematical functions in describing the standard curve shape of Iranian Holstein dairy cows. Among the mathematical functions used for milk yield, Wilmink model had a better fit while for milk fat percentage and milk protein percentage, Ali-Schaeffer model showed a better fit performance. Therefore, it could be suggested that brnn is an appropriate option to be applied to fit the lactation curve of Iranian Holstein dairy cows.

To investigate the qualitative characteristics and their effects on the economic value of the mohair of Markhoz goats in Kurdistan province, a total of 136 samples from seven flocks, two groups: yearling goats and adult female goats and seven colors: white, cream (straw colored), cream brown, light brown, red-brown, dark brown and black, were sampled in the mohair harvest season. The characteristics investigated in this research included: true fibers, modular fibers, kemp fibers, fiber diameter, staple length, and economic value of fibers. In this research, the statistical analysis was done using version 27 of Spss. Fixed effects of flocks, goat groups and fiber colors were investigated on the variables, and the GLM procedure of the software was used. The least-square means of true fibers (%), modular fibers (%), kemp fibers (%), fiber diameter (microns), staple length(cm), and the price per kilogram of mohair (Rials) were 92.36±5.14, 6.84±4.81, 0.75±1.02, 32.49±5.27, 14.46±3.27 and 1823308±452, respectively. According to the results of this research, the color significantly affected the mohair pricing (p˂0.01). The low amount of kemp and modulated fibers in the pure goats did not affect the mohair price. However, a combination of particular colors and one of the advantages of the mohair elegance or long length of the staple made the highest price to be assigned to the mohair. For this reason, red-brown and straw fibers had the highest price compared to other colors. In terms of desirability, after these two colors, different brown, white, and black colors were placed, respectively.

In the present experiment, the effects of different concentrations of rosemary extract(RE) spray on fertile eggs on the first day of incubation on embryonic parameters and quality of hatched chicks were investigated. Seven treatments were tested in a completely randomized design with five replicates, including five treatments of different concentrations of rosmarinic acid(RA) (0.5,0.1,1.5,0.2, and 2.55 mg/ml of RA) and two treatments of distilled water (with and without spray) on the first day of incubation. The results showed that the weight of the yolk sac of hatched chicks from eggs sprayed with a concentration of 2.55 mg/ml of RA was significantly lower than those from eggs treated with distilled water(P<0.05).There was no significant difference in hatchability percentage and embryonic mortality between unsprayed and sprayed eggs with distilled water compared to RE. The use of RE spray on egg caused a reduction in the body surface temperature(BST) of hatched chicks compared to those from unsprayed eggs(P<0.05). The length of the intestine of hatched chicks from eggs sprayed with 1.5 mg/ml of RA was greater than that of unsprayed and distilled water-sprayed eggs(P<0.05). Finally, the results showed that the spray of RE, with a concentration of 2.55 mg of RA, resulted in a heightened absorption of yolk sacs in hatched chicks compared to those eggs sprayed with distilled water. Moreover, an longer intestinal length was observed using a spray of 1.5 mg of RA, accompanied by a decrease in body surface temperature of hatched chicks in comparison to eggs without any spray.

This study was aimed to optimize the suitable slaughter weight of Afshari fattening male lambs by using the feed conversion ratio curve and carcass tissue composition. Thirty-two Afshari male lambs, averaging 105±15.0 (SD) days of age and initial body weight of 30.2±3.6 (SD) kg, from the commercial herd in the Animal Science Research Institute of Iran were used. Metabolizable energy (ME) contents were, 2.79, 2.78, 2.72 and 2.69 Mcal/kg dry matter (DM) and crude protein (CP) contents were 146, 128, 109, and 103 g/kg for the 1, 2, 3, and 4 diets, respectively. The results showed, DMI and feed conversion ratio (FCR) had an increasing trend, with the increasing length of fattening period. The daily weight gains, had an upward trend from the beginning of the experiment to the 56th day, and then it decreased with a relatively small slope. Dressing percentage increased, with increasing length of the trail, so that it was significantly higher in the last stage of slaughter (55.3%) than the previous (52%). Weight percent of digestive tract (stomach and intestine), liver and, lung decreased but weight percent of internal fat increased, with a significantly difference, when experimental period increased. The highest percent of fat-tail weight, was observed in the last stage of slaughter (19.8) and the lowest was observed in the first stage of slaughter (14.2). Back fat thickness increased with increasing length of the experiment, so that a significant difference observed between the last stage of slaughter and the previous stages.