|Elsasser, Theodore - Ted|
Submitted to: Journal of Dairy Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/14/2005
Publication Date: 1/2/2006
Citation: Quigley, J.D., Wolfe, T.A., Elsasser, T.H. 2006. Effects of additional milk replacer feeding on calf health, growth and selected blood metabolites in calves. Journal of Dairy Science. 89:207-216. Interpretive Summary: For the dairy producer, one of the most significant productivity losses is calf mortality, greater than ten percent, and sickness. Nutritional intervention appears to be a practical approact to deal with this problem. The present study was conducted to evaluate the effects of different milk replacer regimens on the relationships between intake, weight gail and health. Calves fed a variable amount of calf replacer diet consumed more calf milk replacer, less solid starter diet, had greater body weight, rate of body weight gain gain, feed efficiency, had greater incidence of diarrhea and required more veterinary treatments than calves fed the fixed rate of replacer diet. Preweaning mortality tended to be greater when calves were fed the varying diet. Feed costs and cost per kg of BW gain were greater when calves were fed VAR. Profiles of plasma metabolites were generally consistent with source and intake of nutrients. Differences in plasma TNF-' concentration associated with plasma IgG concentration suggests that calves with failure of passive transfer are less able to mount immune responses and, therefore, adaptive responses to inflammatory cytokine expression were less well developed. However, dietary treatment did not significantly affect plasma TNF-' concentration.
Technical Abstract: Our objective was to evaluate effects of increased liquid feeding on growth, intake, efficiency and health parameters in stressed calves. Holstein bull calves (n = 120; approximately 3 to 8 d of age) were purchased from sale barns and dairy farms and housed in fiberglass hutches. In addition, wood shavings contaminated with coronavirus were mixed with clean shavings and added to each hutch prior to start of the experiment. Calves were fed either a fixed amount (454 g/d) of a 20% CP, 20% fat milk replacer to weaning at 28 d or a variable amount (454, 681, 908 and 454 g/d on d 0-7, 8-14, 15-31 and 32-41, respectively) of a milk replacer containing 28% CP and 17% fat. Calves were also fed commercial calf starter and water for ad libitum consumption. Most calves had plasma IgG concentration on arrival at the facility < 10 g/L. Intake, change in body weight, feed efficiency, morbidity and mortality and selected plasma metabolites were determined. Body weight at 28 d, 56 d, daily BW gain, intake of milk replacer, fecal scores, d with diarrhea, and d treated with antibiotics were increased with feeding variable amount of milk replacer over the 56-d study. Starter intake from d 1 to 56 was reduced from 919 to 717 g/d in calves fed fixed and variable amount of milk replacer, respectively. Morbidity, measured as the number of days that calves had diarrhea, was increased by 53% when variable amount of milk replacer was fed. Calves fed variable milk replacer were treated with antibiotics for 3.1 d compared to 1.9 d for calves fed 454 g of milk replacer/d. Concentrations of plasma glucose, urea N, and IGF-1 were increased when calves were fed variable amount of milk replacer. There was no effect of milk replacer feeding on concentrations of non-esterified fatty acids, total protein, or growth hormone concentrations. Plasma tumor necrosis factor-a was greatest in calves with highest plasma IgG concentrations on the day of arrival and may be related to the calf’s ability to identify pathogens in the environment. Calves fed variable amount of milk replacer and exposed to immunological challenge prior to weaning had BW gain, but also increased incidence of diarrhea that required added veterinary treatments. (Key Words: Calf, Milk replacer, Growth, Morbidity, Mortality) Abbreviation key: CON = fixed rate of milk replacer feeding (454 g/d to 28 d), CMR = calf milk replacer, CS = calf starter, GAM = variable rate of CMR feeding with addition of product containing bovine serum; GH = growth hormone, IGF-1 – insulin-like growth factor-1, NEFA = non-esterified fatty acids, PUN = plasma urea N, TNF-' = tumor necrosis factor alpha, VAR = variable CMR feeding from d 0 to d 42.