Heat-treated colostrum and reduced morbidity in preweaned dairy calves: Results of a randomized trial and examination of mechanisms of effectiveness

Abstract

A randomized controlled clinical trial was conducted using 1,071 newborn calves from 6 commercial dairy farms in Minnesota and Wisconsin, with the primary objective being to describe the effects of feeding heat-treated colostrum on serum immunoglobulin G concentration and health in the preweaning period. A secondary objective was to complete a path analysis to identify intermediate factors that may explain how feeding heat-treated colostrum reduced the risk for illness. On each farm, colostrum was collected each day, pooled, and divided into 2 aliquots; then, one aliquot was heat-treated in a commercial batch pasteurizer at 60°C for 60 min. Samples of fresh and heat-treated colostrum were collected for standard microbial culture (total plate count and total coliform count, cfu/mL) and for measurement of immunoglobulin G concentrations (mg/mL). Newborn calves were removed from the dam, generally within 30 to 60 min of birth, and systematically assigned to be fed 3.8L of either fresh (FR, n=518) or heat-treated colostrum (HT, n=553) within 2h of birth. Venous blood samples were collected from calves between 1 and 7d of age for measurement of serum IgG concentrations (mg/mL). All treatment and mortality events were recorded by farm staff between birth and weaning. Regression models found that serum IgG concentrations were significantly higher in calves fed HT colostrum (18.0 ± 1.5 mg/mL) compared with calves fed FR colostrum (15.4 ± 1.5 mg/ml). Survival analysis using Cox proportional hazards regression indicated a significant increase in risk for a treatment event (any cause) in calves fed FR colostrum (36.5%, hazard ratio=1.25) compared with calves fed HT colostrum (30.9%). In addition, we observed a significant increase in risk for treatment for scours in calves fed FR colostrum (20.7%, hazard ratio=1.32) compared with calves fed HT colostrum (16.5%). Path analysis suggested that calves fed HT colostrum were at lower risk for illness because the heat-treatment process caused a significant reduction in colostrum total coliform count, which was associated with a reduced risk for illness as a function of improved serum IgG concentrations.

Composition and properties of bovine colostrum: a review

“…Johnson et al (2007) described increased efficiency of IgG absorption and, consequently, higher serum IgG concentration in calves fed heat-treated (60°C for 60 min) compared to raw colostrum. These results are consistent with those of Godden et al (2012) who, in addition, reported that calves fed heat-treated (60°C for 60 min) colostrum were at significantly lower risk for treatment of any illness in the preweaning period compared with calves fed unheated colostrum. The precise reason for this remains unclear, but it was hypothesised that the presence of bacteria in colostrum could interfere with systemic absorption of Ig molecules in the small intestine.…”

Avaliação funcional dos fagócitos do sangue e da secreção mamária de vacas no período pós-parto imediato

“…Apesar de os fagócitos mamários terem origem sanguínea, estudos demonstraram que eles podem ter sua capacidade fagocítica comprometida, em relação àqueles presentes na circulação sanguínea, por conta da fagocitose da gordura e caseína (PAAPE et al, 2003) e da curta meia-vida, levando à redução do burst respiratório e morte por apoptose (MEHRZAD et al, 2001), entretanto pouco se sabe ainda sobre a atividade funcional dessas células na secreção colostral, uma vez que a obtenção celular é prejudicada pela presença abundante de debris, gordura, proteínas e partículas autofluorescentes (GOMES et al, 2014;MEGANCK et al, 2014), além da baixa viabilidade (GODDEN et al, 2012).…”

Effect of anaerobic bovine colostrum fermentation on bacteria growth inhibition

“…To ensure administration of contaminant free milking, researchers have recommended the use of commercial substitutes for colostrum (GODDEN et al, 2012;PRIESTLEY et al, 2013).…”