اثرات تغذیه یک افزودنی سین بیوتیکی بر عملکرد رشد و سلامتی گوساله های هلشتاین

This study evaluated the effects of a commercial symbiotic product containing a probiotic (E. faecium), a prebiotic (Fructo­oligosaccharide) and a phytogenic compound (sea algae­extract) on performance and health of Holstein diary calves. 29 newborn calves were assigned by sex and birth date to 10 blocks and allocated to 3 treatments; control (CON, n = 9); CON supplemented with symbiotic via milk (5 g /calf /d) from d 3 of age (SYN3; n = 10); and CON supplemented with symbiotic via milk from d 30 of age (SYN30; n = 10). Calves were abruptly weaned based on the consumption of a minimum of 680 g/d of starter feed for 3 consecutive d and immediately moved to group pens, where they received the respective additives via starter feed until d 75. Body weight (BW) and body growth measures were recorded biweekly during pre­weaning and weekly during post­weaning period. Feces were scored weekly and sampled on d 14, 42 and 70. Blood samples were taken on weaning day, 24 h post­weaning and d 75. During the first 2 wk of the experiment, BW decreased in the CON and SYN30 groups (­890 and ­­240 g, respectively), while it was increased numerically in SYN3 group (+500 g). Mean BW was higher in SYN30 than SYN3 and CON groups (62.9 vs. 59.9, and 59.2 kg, respectively, P < 0.05). However, treatments did not affect final weight, ADG, pre­weaning starter intake, and weaning age. Also, there were no significant differences between treatments in fecal microbial count and blood parameters. Overall, except for a higher mean BW in SYN30 treatment, simultaneous supply of pre­ and pro­biotics and phytogenics as well as time of supplementation did not affect performance and health-related parameters in dairy calves.