الفهرس 
cover englishOnly 14 pages are availabe for public view
 |  | from | 111 |  |  |
| | | from | 111 | | |
Abstract
In the current study two experimental feeding trials were conducted to visualize the effects of feeding two types of feed additives in daily milk intake on performance, antioxidant status and incidence of diarrhea in neonatal Holstein dairy calves.
The first trial was designed to study the effect of feeding a multispecies probiotic containing Bacillus subtilis, Bacillus licheniformis and Enterococcus faecium on performance and incidence of diarrhea in neonatal Holstein dairy calves. A total of twenty-four mixed sex newborn Holstein calves (12 males and 12 females) were randomly distributed into three experimental groups. The first group served as control group (CON) and was fed three times daily on whole milk only without any additives. The second group (PRO5) was fed on whole milk supplemented with 20 grams of the probiotic for five successive days only. The third group (PRO10) was fed on whole milk supplemented with 20 grams of the probiotic for ten successive days. The experiment lasted for 20 days. Results revealed that body weight and body weight gain were not significantly affected by probiotic supplementation, however, heart girth tended to increase in probiotic supplemented calves (P = 0.08). Incidence of calf diarrhea was 50% in CON, and 37.5% in both PRO5 and PRO10 groups. Serum levels of aspartate aminotransferase (AST) and reduced glutathione (GSH) were significantly reduced (P = 0.05), while globulin level tended to increase (P = 0.10) in both probiotic treated groups compared to the control group.
The second trial was designed to study the response of neonatal Holstein calves to dietary supplementation of lysolecithin as an emulsifier. A total of eighteen (18) newly born female Holstein dairy calves were randomly allotted into three experimental groups 6 calves each. The first group (CON) was fed three times daily on whole milk only and served as control group. The second group (LECL) was fed on whole milk supplemented with lysolecithin at the rate of 6 grams/head/day. The third group (LECH) was supplemented with lysolecithin at the rate of 12 grams/head/day. Calf starter was offered free choice to all calves in the different experimental groups starting from two weeks of age. The experiment lasted for 84 days (weaning age). Results showed that, lysolecithin supplementation did not significantly affect final body weight (P > 0.05). Calf starter intake was reduced in response to the emulsifier supplementation (P < 0.001). Serum levels of alanine aminotransferase (ALT), AST (P < 0.01), creatinine (P = 0.04), albumin (P = 0.05), albumin: globulin (A: G) ratio (P = 0.01) and triglycerides (P = 0.05) were reduced in both groups supplemented with the emulsifier compared to the control group. Very low-density lipoprotein (VLDL) level was significantly decreased (P = 0.03) by lysolecithin supplementation in a dose dependent manner. Phosphatidylinositol (PI) was significantly increased in emulsifier supplemented groups regardless of the dose (P = 0.004), and phosphatidylserine (PS) fraction was significantly increased in response to supplementation in a dose dependent manner (P = 0.001). Catalase (CAT) level was significantly reduced only in the higher dose of the emulsifier (P = 0.01).
It could be concluded that dietary supplementation of multispecies probiotic in daily milk intake of neonatal Holstein calves has a positive impact on performance, as well as in reduction of the incidence of diarrhea. In addition, the use of emulsifier (lysolecithin) improves general health status, antioxidant status and serum lipids with limited effect on body weight gain.