مجله دانش و پژوهش علوم دامی
سال بیست و سوم شماره 1 (پیاپی 23، زمستان 1401)

This study was conducted to investigate the effects of sour tea powder on growth performance and immune responses of broiler chicks under conditions challenge with ascites. 400 broiler chicks were studied in arrangement of 4 experimental diets including: Treatment 1: Positive control group (without induction of ascites and without powder), treatment 2: Negative control group (induction of ascites without powder), Treatments 3 and 4) 1% and 2% sour tea powder groups with ascites induction, and inclusion of 1% and 2% tea powder. This study was conducted for 42 days and the induction of ascite was started from day 8. This study was conducted in form of a completely randomized design with 4 treatments and 5 replications. Performance parameters (body weight, feed intake and feed conversion ratio), immune responses against SRBC, weight of immune organs (spleen, thymus and bursa) and heart indexes were investigated. The results showed that the induction of ascites decreased body weight and increased feed conversion ratio in finisher period. The induction of ascites also decreased relative weight of heart indexes, immune organs and antibody titer (p<0.05). Dietary inclusion of 2% plant powder increased growth performance in finisher and total periods. It also improved relative weight of immune organs and antibody titer against SRBC. In conclusion, adding 2% Sour tea powder into diet is suggested to improve immune responses and growth performance under ascites condition.

The aim of this study was to evaluate the effect of adding different levels of Rosemary extract with two different dose of glycerol on the motility, viability and membrane integrity of Moghani rams semen after freeze-thawing process. Semen was collected from four healthy and mature Moghani rams (3-4 years), twice a week for 3 weeks. Afterward the samples were evaluated and pooled for altering individual effects. After that the pooled semen was divided in to aliquots and extended with the treatments including 3 levels (0, 2 and 6 percent of rosemary extract with 5 or 7 percent of glycerol. then semen equilibrated at 5 ºC for 2 h, and aspirated into 0.25 mL straws. After equilibration, straws were frozen in liquid nitrogen vapor and plunged into liquid nitrogen for storage. Sperm parameters, including motility, viability, membrane integrity, and progressive motility by CASA (Computer Assisted Sperm Analysis) software were assessed. The results showed that the treatment supplemented with 2 percent of rosemary extract including 5 percent of glycerol could improve total and progressive motility, viability and membrane integrity (P>0.05). There were no any significant differences for VCL, VSL, ALH and VAP parameters among the experimental treatments (P> 0.05). In conclusion it is proposed that addition of 2 percent of rosemary extract with 5 percent of glycerol could improve the quality of Moghani ram sperms parameters after freeze-thawing process.

In this study, the buffering resistance pattern of sodium bicarbonate, sodium sesquicarbonate, magnesium oxide, magnesium carbonate, sodium bentonite, and zeolite were statistically compared by plotting the titration curve and comparing the slope of the curves. According to the results of the buffer capacity, raw materials and their percentages were determined to produce the optimized multi-component buffer.  The produced buffer acid-pH curve slope was compared with other slopes. No significant difference was observed in the slope of the optimized buffer with sodium bicarbonate (p <0.05). To ensure optimal buffer performance under ruminal conditions, experimental diets of low concentrate diet without buffer additive (CF), high concentrate diet without buffer additive (CC), low concentrate diet + 1% sodium bicarbonate (NF),  high concentrate diet + 1% sodium bicarbonate (NC), low concentrate diet + 1% optimized buffer (BF) and high concentrate diet + 1% optimized buffer (BC), were examined with gas production test at 2, 4, 6, 8, 12 24, 48, 72 and 96 after incubation in ruminal fluid. The use of buffer additives has positive effects on maintaining acid-base balance in the rumen and thus improving the ecology of rumen microorganisms, which was accompanied by a significant increase in gas production (p <0.05). The use of buffer supplements will improve the fermentation process and can significantly increase the digestibility of organic matter and feed metabolizable energy (p <0.05). In addition, the results showed that the optimized buffer has a similar function to sodium bicarbonate and can be used as a suitable alternative.

Being aware of the animals` food requirement, the amount of available forage in the rangeland and forage quality is necessary as the first step in successful management of animals and rangeland. in this study, Animal unit weight equivalent, maintenance metabolizable energy and daily requirement of grazing sheep were studied. Therefore, determining the weight of various animals` classes grazing in the rangeland and their conversion factor regarding country`s animal unit is an essential issue. In this research, to determine the weight of various classes of Zandi sheep grazing in the Lar National Park rangelands of Siah Palas region in position 35 degrees and 54 minutes north latitude and 32 degrees and 52 minutes east longitude, three prevalent flocks of Zandi race  were selected randomly and from each flock, 60 heads of animals including 20 heads of ewe ageing 3 years old, 20 heads of ewe aging 4 years old, 5 heads of ram aging 3 years old, 5 heads of ram aging 4 years old and 10 heads of lamb aging 3 months were signed and selected in two phases, one at the beginning of the season and the other at the end of season. Having utilized the mean weight of ewes aging 3 and 4 years, the weight of the sheep glazing in the studied region was estimated to be equal to 1.59±49.96 kg. Various kinds of forage being glazed by the sheep were identified and collected in this rangeland at the flowering stage on 05/06/2019. The mean percentage of CP, ADF, DMD and ME in every kg of dry forage for 41 plant samples equaled to 4.77±11.18, 39.19±7.89, 56.11±7.83, 7.58±1.26 mega joule, respectively. Daily metabolizable energy for maintenance condition of animal unit equation of this rangeland  for 120 ewes, equaled to 10.54 ± 0.35 mega joule in a day and its daily need was estimated to be 1.38±0.04 kg based on the consumed dry material and considering the quality of the forage. Overall, being aware of daily food needs is necessary for the diet of animals. It should be considered in providing managerial designs.

This study was conducted to evaluate the effect of Thyme and Garlic powder on the quantity and quality of production, and some blood parameters on 128 hens of Hyline breed, Strains of W36 at 46 weeks of age. The experimental design was Completely Randomized Design with four treatments and four replications in 12 weeks and each experimental unit contains 8 laying hens in two cages. Treatments include (1) Blank diet without thyme and garlic, (2) Diet contain of thyme 0.5% with garlic 1%, (3) Diet contain of thyme 1% with garlic 1%, (4) Diet contain of thyme 1.5% with garlic 1%, in diets based on corn and soybean meal. Studying the results of qualitative and performance traits data showed there were not significant differences between treatments (P≥0.05). Numerically the highest daily egg product mean (53.56 g) and the amount of daily feed intake (92.63 g) and egg weight mean (62.67 g) is related to the treatment No.3, while the lowest feed conversion ratio (1.72) and the highest production percentage (85.86) is related to the treatment No.1. The blood characteristics with 1 percentage of mixed thyme and garlic powder was high significant Compared to other treatments and Blank(P>0.01).In general it can be concluded that qualitative and performance traits of egg were not affected by different levels of thyme and garlic powder but unlike Uric acid blood parameters(Total protein and Albumin) showed significant improvements.

This study was performed to evaluate of effect corn and wheat gluten individually and combination on performance and carcass traits broiler chickens. The experiment was performed using 400 broilers Ross 308 with the same initial weight in a completely randomized design with 4 treatments and 5 replications of 20 pieces for mixed sex and in a period of 42 days. The treatments included: 1- Control. 2- Corn gluten (5 %). 3- wheat gluten (4 %). 4- Mixed corn gluten (2/5 %) + wheat gluten (2 %).The measured experimental characteristics were; feed intake, weight gain, feed conversion and production index. At the end of experimental period one bird was selected randomly from each replicate and slaughtered and carcass characteristics were measured. Results from compare means by duncan test showed that wheat gluten treatment significantly better performance in terms of feed intake, feed conversion ratio and production index is compared to other treatments. But in the case of weight gain, there is no significant difference between treatments. Wheat gluten treatment had a better carcass characteristics in terms of percentages of carcass, breast, thighs, wings and parts of the digestive system is compare to other treatments.