Characteristics of dairy calf ranches: Morbidity, mortality, antibiotic use practices, and biosecurity and biocontainment practices

Abstract

The utilization of farming operations specializing in rearing dairy heifer calves has increased since the early 1990s. However, these operations have not been as well characterized as US dairy operations with respect to demographic and health-related measures, particularly during the preweaning period. The objective of this study was to characterize morbidity, mortality, antibiotic use, and biosecurity and biocontainment practices on operations rearing preweaned heifers only or preweaned heifer and bull calves (mixed) in the United States. A cross-sectional survey was performed using a standardized method that included a preletter, initial survey, postcard follow-up, and second survey delivered by mail. Additional follow-up contacts were attempted by telephone. Descriptive statistics for morbidity, mortality, antibiotic use, and biosecurity and biocontainment practices were computed at both the operation and calf levels. The overall response rate was 50%. Crude yearly mortality averaged 6.9% at the calf level, with the median operation reporting 3.6% mortality. Diarrhea was experienced by 18% of calves, with 73% receiving an antibiotic. The median operation reported 20% diarrhea morbidity with 83% receiving an antibiotic. Respiratory disease was experienced by 9.0% of calves, with 82% receiving an antibiotic. The median operation reported 5.3% respiratory morbidity, with 100% receiving an antibiotic. Heifer-only and mixed operations did not differ in operation median morbidity, mortality, or antibiotic treatment rates. Written antibiotic protocols were available on 65% of operations. Medicated milk replacer was used by 56% of operations. Passive immunity was routinely measured by 46% of operations. Direct contact between calves in housing units was not allowed by 45% of operations. Of all farms informed of disease concerns at the source farm, 76% changed their daily routine as a result. Almost all operations uniquely identified calves and recorded mortality. The heifer-only and mixed operations in this study were similar to US dairy operations for key health, antibiotic use, and biosecurity and biocontainment metrics. This research provides initial estimates of key demographics usable by calf ranches, veterinarians, and other professionals serving this segment of the US dairy industry.

A survey of dairy calf management practices in some producing regions in Brazil

“…In several countries, some studies have already been conducted to understand how producers raise replacement animals (Machado Neto et al, 2004;Kehoe et al, 2007;Vasseur et al, 2010;Walker et al, 2012). Through these studies, it was possible to provide information on handling regarding the feeding and health management of the calves, all of which contribute to a reduction in the animal mortality and morbidity rates.…”

Pre-slaughter mortality and post-slaughter wastage in bobby veal calves at a slaughter premises in New Zealand

“…Other studies have generally not noted omphalitis as a significant cause of calf mortality, but 10-15% of calf deaths have been attributed to septicaemia (Virtala et al 1996;Bähler et al 2012) or idiopathic peritonitis (Pardon et al 2012a) and it is possible that these infections originated in the umbilicus. Antibiotic usage is common in calf rearing or white veal systems (Sargeant et al 1994;Pardon et al 2012b;Walker et al 2012), but not in bobby veal systems and this most likely accounts for the marked difference in omphalitis-related mortality.…”

Prenatal stress, immunity and neonatal health in farm animal species

“…The major mortality and health problems are due to hypothermia, hypoxia or starvation. Maternal undernutrition, mismothering, injury and infection represent a significant part of morbidity and mortality after the perinatal phase (Mellor and Stafford, 2004;Baxter et al, 2012;Walker et al, 2012). Management practices dedicated to improve neonatal survival and health are mainly focusing on the young animal itself, on its direct environment, or on the maternal qualities of the lactating mother.…”