Friday, February 27, 2015

Health Benefits Among Weaned Heifers Associated with
Higher Plane of Nutrition as Preweaned Calves

In a experiment with a small number of Jersey calves researchers orally challenged them with a Salmonella  Typhimurium. These post-weaning calves (80 days old) represented two levels of pre-weaning nutrition - a low level of milk replacer (just under 1 pound of 20-20) [LPN] and a higher level (1.6 pounds of 28-25) [HPN].

After the Salmonella challenge the HPN calves consistently scored higher on a series of indexes that reflect the strength of immune system response to pathogens. In addition, as an indirect indicator of how the calves were feeling, at 9 days after the Salmonella  challenge the HPN calves were eating about 6 pounds of calf starter daily compared to the LPN calves that were eating 1.7 pounds less daily.

So, with these limited data we can conclude that there is a post-weaning health payoff for seeing that young calves have plenty to eat during the pre-weaning period.

As an interesting side note regarding diarrhea among the youngest calves, the reported scours rate among the 7-10 day-old calves was 46 percent for LPN and 88 percent among HPN calves. No explanation was given for what I consider elevated scours rates among both groups. The blood serum total protein levels were quite uniform and high (average =  6.1). I conclude that pathogen exposure during the first day of life must have been substantial because they all started scouring at 7 days of age. The scours lasted about 4 days for LPN calves and 6 days for HPN calves. No long-term negative effects of scouring was reported for either group of calves.

[Reference: Ballou, M.A. and Others, "Plane of nutrition influences the performance, innate leukocyte responses, and resistance to an oral Salmonella enteria serotype Typhimurium challenge in Jersey calves," Journal of Dairy Science March, 2015 Vol. 98, pp 1972-1982] 

No comments:

Post a Comment