Can We "Super Charge" Colostrum Using Pre-partum Supplementation?

Background

High quality colostrum is essential for calf health and growth. Calves that do not receive adequate amounts of high-quality colostrum after birth are more likely to get sick, have poor performance, or even die. During the final two months of gestation, cows experience increased nutrient demand due to exponential fetal growth, meaning cow nutrition is critical at this point to maintain adequate cow condition, as well as colostrum production. Previous work has shown that cows that are supplemented with excess energy prior to calving showed minimal calf size effects, but an increase in colostrum quality and output, as well as minimized condition loss in cows. Due to the expense of supplementation with commodities such as corn, it is important to investigate the effect of duration of supplementation on cow and calf performance, as well as colostrum yield and quality.

Objectives

Investigate if prepartum energy supplementation for either 3 or 6 weeks prepartum can increase the quality and quantity of beef colostrum, as well as the impact of this supplementation on calf growth, and calf health.

What they did

This group looked at providing cows with supplemental energy for 3- or 6-weeks pre-calving to assess the effect on colostrum quality and calf growth and health. They used 82 crossbred cows that were bred using AI. The cows were housed at the Ontario Beef Research Centre and grouped by predicted calving date. Cows were enrolled on diets that met energy requirements (Control; no supplement) or provided energy at 120% for 3 weeks (3WK) or 6 weeks (6WK) prior to calving. Diets were delivered as TMR and were fed to cows through Insentec feeders that allow for feed intake and feeding behaviour to be recorded. Cow weights, rib and rump fat and metabolites were followed for 6 weeks prepartum and 9 weeks postpartum. Colostrum was collected from cows at calving and was analyzed for yield, composition, and IgG (an antibody important to the calf immune system). Colostrum was then fed back to the calves. After calving, cows had access to a common lactation ration. Calves were followed for 9 weeks post-calving and weights and IgG were analyzed.

What they Learned

The results of this study did not find differences in colostrum yield or composition as a result of over-supplementation, nor were there differences due to duration of over-supplementation of energy. When analyzing components, fat, crude protein, lactose, gross energy, and somatic cell count were not affected by energy supplementation for 3 or 6 weeks. Urea was greater in the colostrum of cows that were not supplemented, due to the presence of urea in their diet.

Cow performance was not different before calving. Cows that were supplemented energy did not gain more rib or rump fat depth, nor did they gain more weight. Metabolic markers of fat mobilization (non-esterified fatty acids) were greater for cows that were not supplemented with energy prepartum, suggesting that the cows that were not supplemented had insufficient energy and had to use more body reserves to meet their energy demands, relative to cows that were supplemented. The severity of the insufficient energy was not great enough to impact performance. After calving, the cows that were not supplemented still had greater metabolic markers of fat mobilization to meet energy demands. These cows also lost weight after calving, whereas the cows that were supplemented gained weight. Calf birth weight was not different as a result of supplementation. Calves from cows that were supplemented for 6 weeks had greater average daily gain for the first 7 days of life than calves from cows that were supplemented for 3 weeks. After the first 7 days of life, calf weights and average daily gain were not affected by the supplementation of the cow before calving. Calf IgG, an important antibody to calf immunity in early life, was also not affected by supplementation of the cow prior to calving.

What This Means

The results of this study suggest that energy supplementation of cows for 3 weeks or 6 weeks prior to calving did not affect calf performance or colostrum yield and composition, compared to cows that did not receive supplemental energy before calving. Despite the absence of effects on calf performance and colostrum, supplementation of energy did appear to reduce the mobilization of the cow’s own body reserves to meet her energy demands. This is beneficial to producers, as loss of body condition around calving can increase the risk of disease in the cow and can delay rebreeding. Restoring a cow’s body condition after it is lost can also be costly to producers. Calf birth weights, in relation to calving ease, are often a concern with supplementation prior to calving. Supplementation did not increase calf birth weight.