Location: Livestock Behavior Research
Project Number: 5020-32000-014-063-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2020
End Date: Aug 17, 2023
The study objective is to evaluate the efficacy of supplementing milk replacer with 1.0% L-glutamine on improving health, growth performance, and welfare of dairy calves.
Dairy calves are removed from the dam within hours after birth and then individually housed with no environmental enrichment and no access to the dam or other calves. This is a stressful process that often results in reduced growth, increased disease prevalence, and reduced welfare, especially for those calves that receive insufficient quantities of quality colostrum. As such, the U.S. dairy industry frequently treats sick calves with antibiotics to control disease onset and improve growth performance and welfare. Unfortunately, the prevalence to which antibiotics are provided in the dairy industry may lead to antibiotic-resistance, and consumers, legislators, and scientists are pushing for the reduction of antibiotic use in animal agriculture. To address this concern, many researchers have focused on developing antibiotic alternatives that reduce the use of antibiotics in animal agriculture by improving disease resistance. Specifically, several studies by our group have reported improved responses in growth performance, immune function, intestinal development, and overall health in newly weaned pigs provided L-glutamine following weaning and transport. Therefore, the study objective is to determine whether supplementing milk replacer with 1.0% L-glutamine will improve the intestinal function, growth performance, disease resistance, and stress response of calves from birth to weaning and reduce the use of antibiotics to treat disease. Because newborn dairy calves are considered monogastrics (similar to pigs) and are subjected to similar stressors as pigs (i.e., early removal from dam, stressful environment, etc.), we hypothesize that the intestinal function, growth performance, disease resistance, and stress response of dairy calves supplemented with 1.0% L-glutamine will be improved compared to those provided milk replacer supplemented with no L-glutamine. Newborn heifer calves will be removed from the dam, weighed, given colostrum, and then individually housed. Following colostrum administration starting at 2-days old, calves will be provided milk replacer supplemented with either no-supplement or 1.0% L-glutamine until weaning. During testing, physiological measures of inflammation, stress, intestinal function and metabolic health will be taken. Body weight will be assessed in 7-day intervals until weaning and total milk replacer consumption will be recorded daily. Rate of therapeutic injection for disease and reason for injections will be recorded from birth to weaning. Visual observations of behavioral indicators of stress and illness (i.e., posture, lethargy, etc.) will be recorded twice daily during the first 14 days of life.