The effects of adding Pistacia Atlantica atlantica subsp. kurdica kurdica gum essential oil to the diet of ewes during late pregnancy on milk yield, components, and the growth of suckling lambs

The growth and health of lambs from birth to weaning are influenced by yield and quality of the ewe's colostrum. Colostrum contains essential proteins, fats, hormones, vitamins, and antibodies that facilitate immunity, growth, and development. Therefore, to improve colostrum, it is necessary to use a quality diet. That colostrum is of high quality to ensure the best start to life for offspring. Consumption of high-quality colostrum improves neonatal survival and increases the reproductive potential and future productivity in sheep. Some plant essential oils have been used to improve ewes health and their productivity. This experiment was conducted to evaluate the effect of feeding different levels of Pistacia Atlantica Kurdica gum essential oil on feed, intake, the quality of colostrum, milk yield, and milk composition, and growth of suckling lambs.

Pistacia Atlantica Kurdica gum essential oil was prepared commercially and added to the ewes' diet in order to influence the Pistacia Atlantica Kurdica gum essential oil during pregnancy and lactation (it lasted for 5 months and the habituation time was 21 days). A herd of 168 ewes (which were in the second and third pregnancy and the average weight of the ewes was 68.84±1.65 kg), all of which were subjected to the estrus synchronization program. Ninety pregnant ewes in the last month of their pregnancy were randomly divided into three groups. The first group did not receive any essential oil, and the second and third groups received a daily dose of 0.8 and 1.6 milliliters of Pistacia Atlantica Kurdica gum essential oil, respectively. The Pistacia Atlantica Kurdica gum essential oil was sprayed on the feed of just before each meal. At the time of parturition, 36 single-born female lambs and their dams were randomly assigned to the three experimental groups. Each group was further subdivided into 4 units of three ewes each to determine dry matter intake. All other data such as milk production and composition, colostrum, and lambs growth data were obtained from 12 ewes and their lambs in each treatment.

Both groups treated with Pistacia Atlantica Kurdica gum essential oil had positive effects on increasing dry matter and milk production, but ewes received a daily dose of 1.6 ml of Pistacia Atlantica Kurdica gum essential oil had the highest DM intake and milk production (P<0.05). The essential oil had no effect on the birth weight of lambs (P<0.05). Feeding the essential oil had a significant effect on fat, protein, and solid none fat in colostrum and milk. Somatic cells both in colostrum and milk declined as a result of feeding Pistacia Atlantica Kurdica gum essential oil(P<0.05).

The essential oil had a significant and positive effect on the somatic cells of colostrum and milk and caused it to decrease in the treatments containing essential oil. Because of the significant positive effect of Pistacia Atlantica Kurdica gum essential oil on milk production, milk and colostrums composition (fat and protein) and the growth rate of suckling lambs, it is concluded that this essential oil could be recommended as a suitable feed additive in the diet of ewes at a dose of 1.6 ml/d.