نوع مقاله : مقاله پژوهشی
نویسندگان
1 1 استادیار بخش پژوهش های بیوتکنولوژی، موسسه تحقیقات علوم دامی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج ، ایران. رایانامه:
2 گروه تغذیه دام و طیور، دانشکده علوم دامی، دانشگاه گرگان
3 3 گروه تحقیقات علوم دامی مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی گرگان، گرگان، ایران. رایانامه: flowermino@gmail.com
4 4 دانشجو دوره دکتری، گروه علوم دامی، دانشکده کشاورزی، دانشگاه تربیت مدرس، تهران، ایران. رایانامه: teymouriayda2000@gmail.com
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The transition period in ewes, which usually lasts three weeks before and three weeks after parturition, is one of the most critical physiological stages during the reproductive cycle. During this period, the ewes undergo extensive metabolic and hormonal changes that are necessary to prepare the body for parturition and the onset of lactation. Late pregnancy is associated with reduced feed intake and increased energy requirements due to rapid fetal growth and mammary gland development. This mismatch between energy intake and requirements leads to negative energy balance (NEB), which results in the mobilization of body fat stores and an increase in the concentration of non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHBA) in the blood. These changes predispose to the development of ketosis, fatty liver, and preeclampsia in ewes. Negative energy balance also increases the production of reactive oxygen species (ROS) and oxidative stress, which weakens the immune system and increases the risk of inflammation and metabolic and infectious diseases. As a result, colostrum quality, first milk production and lamb growth are affected. In these conditions, vitamins and minerals, especially those with antioxidant properties, play an important role in reducing oxidative stress and maintaining immune health. Adequate and balanced supply of these micronutrients during the transition period improves the immune response, reduces the incidence of metabolic disorders and increases production performance. Therefore, targeted nutrition rich in antioxidants during the transition period is crucial for the health and productivity of ewes.
Materials and Methods: The present study was conducted to investigate the effect of vitamin and mineral supplementation injection in late pregnancy on performance, digestibility, milk production, and inflammatory indices of Dalagh ewes. The study used 40 Dalagh ewes with a mean weight of 42 ± 3.7 kg, which were divided into four treatments and ten replications in a completely randomized design in late pregnancy. The experimental treatments included: 1) control group (no vitamin and mineral supplementation injection), 2) ewes receiving injectable vitamin supplementation, 3) ewes receiving injectable mineral supplementation, and 4) ewes receiving simultaneously injectable vitamin and mineral supplementation. To determine the amount of dry matter consumed daily, the after-feed was collected and weighed before the new feed was fed. The amount of milk production and composition were measured and recorded. To measure the digestibility of the ewes, fecal and feed samples were collected in the last five days of the experiment to determine the digestibility of dry matter, organic matter, crude protein, ether extract and neutral detergent insoluble fiber. To measure inflammatory indices and blood antioxidant status,
Results: The results of the effect of mineral and vitamin injection in late pregnancy showed that minerals and vitamins improved the final weight and feed consumption of ewes after calving, and the highest feed consumption was for ewes injected with minerals and vitamins simultaneously (P<0.05). Also, minerals and vitamins improved the digestibility of dry matter and neutral detergent insoluble fiber in ewes (P<0.05). On the other hand, minerals and vitamins had no effect on the amount of milk production, protein, fat, and lactose in ewes. On the other hand, mineral and vitamin injection reduced BHBA, NEFA, ROS, and OSI and increased SAC in ewes at all three times (P<0.05). The greatest improvement in NEFA at all times, ROS before calving and on the day of calving, and SAC and OSI before calving were related to ewes receiving minerals and vitamins simultaneously.
Conclusion: Considering the improvement in weight performance, digestibility, and inflammatory markers of ewes, simultaneous injection of minerals and vitamins is recommended for ewes in late pregnancy.
کلیدواژهها [English]
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