The Effect of Iranian and Foreign Milk Substitutes on Performance, Blood Parameters, Characteristics of Internal Carcass Organs and Rumen Development of Lambs at Weaning

Extended Abstract Introduction and Objective: The advantages of using milk replacer include proper growth of lambs, prevention of consumption of bodily reserves of mother ewes, preparation of ewes for the next calving period, reduction of calving distance, increase of twinning and reduction of costs. The aim of this study was to investigate the effect of milk replacer on Performance, blood parameters and rumen development. Material and Methods: In this study, 42 newborn male and female lambs (equal numbers of each sex) of Ghezel breed were used. Treatments in each sex group included 1- whole milk of ewes that were placed next to the mother ewes in two meals in the morning and evening every 12 hours and the starter diet that was freely given to the lambs as a control group. 2- Milk replacer 1 (Iranian) that 15% of body weight with the starter diet was given to lambs freely. 3- Alternative to milk 2 (foreign), which was given 15% of the body weight to the lambs freely with the starter diet. 7 lambs were assigned to each treatment in each sex. Milk replacers were also provided to lambs in the morning and evening until weaning. Feed intake was measured daily. The lambs were weighed every two weeks. Blood samples were taken on days 35 and 75 to determine the effect of milk replacer on blood parameters. In the thirteenth week, male lambs were slaughtered and the characteristics of the internal organs of the carcass and their rumen development were measured. Results: The results showed that milk substitutes increased feed intake, which was the highest increase in lambs receiving Iranian milk substitutes (p<0.01). Also, feed consumption in male lambs was more than female lambs and with increasing age of lambs, feed consumption also increased significantly (p<0.01). Data on weight gain after weaning of lambs showed that lambs receiving Iranian and foreign milk substitutes gained more weight than lambs receiving breast milk (p<0.01). None of the studied blood parameters except glucose were affected by Iranian and foreign milk substitutes and also the sex of lambs. Liver (p<0.01) and spleen (p<0.05) weights were highest in control groups and lowest in Iranian milk substitutes. Also, ventricular fat was the highest in the Iranian milk substitute group (p<0.05). The rumen villi of the tested lambs were not significantly affected by milk substitution. Conclusion: According to the positive results observed  in relation to feed intake and  weight after weaning, the use of Iranian milk substitutes in suckling lambs is recommended.