نوع مقاله : مقاله پژوهشی
نویسندگان
1 عضو هیات علمی دانشگاه رازی
2 گروه علوم دامی، دانشکده علوم و مهندسی کشاورزی، ، دانشگاه راز ی ، کرمانشاه ،
3 استاد پژوهشی، بخش تحقیقات تغذیه و فیزیولوژی دام، موسسه تحقیفات علوم دامی ، سازمان تحقیقات ، آموزش و ترویج کشاورزی ، کرج ، ایران
4 استادیار پژوهشی تحقیقات علوم دامی، مرکز تحقیقات ، آموزش کشاورزی و منابع طبیعی ، سازمان تحقیقات ، آموزش و ترویج کشاورزی ، کرمانشاه، ایران.
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and objectives: This study aimed to compare reproductive performance, pre-weaning growth traits, and blood biochemical parameters between purebred Sanjabi lambs and Sanjabi × Romanov crossbred lambs. Evaluation of growth performance and carcass characteristics in purebred Kurdi and Kurdi× Romanov reported .Romanov sheep are characterized by high prolificacy, and their use in crossbreeding programs may improve flock productivity; however, information regarding physiological status and early growth performance of Sanjabi crossbred lambs remains limited.
Materials and methods: The experiment was conducted in 2023 at the Mehrgan Animal Husbandry Research Station, Kermanshah, Iran. A total of 200 Sanjabi ewes were randomly assigned into two groups. The first group was naturally mated with Sanjabi rams, while the second group underwent estrus synchronization followed by laparoscopic artificial insemination using Romanov semen. After lambing, 15 lambs per group were selected and reared under identical feeding and management conditions for 77 days. Body weights were recorded every 15 days, and growth traits including birth weight, periodic weights, average daily gain, and total weight gain were calculated. At 77 days of age, blood samples were collected from five lambs per group before feeding. Biochemical parameters including glucose, urea, total protein, albumin, cholesterol, triglycerides, HDL, LDL, and VLDL were measured along with liver enzyme activities (alkaline phosphatase and aspartate aminotransferase) and malondialdehyde concentration. Data were analyzed using the GLM procedure of SAS software, and means were compared using Student’s t-test (P<0.05).
Results: Crossbred ewes showed improved reproductive performance, with higher lambing rate (88 vs. 81 ewes lambed) and greater number of lambs born (154 vs. 114) compared with purebred Sanjabi ewes. Birth weight did not differ significantly between groups (P=0.64). Purebred lambs had significantly higher body weight at weeks 2 and 4 (P=0.0001 and P=0.006), whereas no significant differences were observed at weeks 6, 8, and 10. Weaning weight and average daily gain were similar between treatments (P=0.86). Blood biochemical metabolites and lipid profiles showed no significant differences between groups (P>0.05). Likewise, liver enzyme activities and malondialdehyde concentrations were not affected by genotype.
Conclusion: Crossbreeding Sanjabi sheep with Romanov increased reproductive indices and prolificacy; however, it had no significant effect on pre-weaning growth performance or the metabolic status of lambs. Based on the obtained data, the average daily weight gain did not differ significantly between purebred Sanjabi suckling lambs and Sanjabi × Romanov crossbred lambs. Likewise, blood biochemical parameters, certain liver enzyme activities, and malondialdehyde levels showed no significant differences during the rearing period.
کلیدواژهها [English]
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