Preweaned heifer management on US dairy operations: Part V. Factors associated with morbidity and mortality in preweaned dairy heifer calves

Abstract

The objective of this study was to evaluate morbidity and mortality in preweaned dairy heifer calves based on different health, feeding, and management practices, as well as environmental factors. This study was conducted as part of the calf component of the National Animal Health Monitoring System's Dairy 2014 study, which included 104 dairy operations in 13 states. The calf component was an 18-mo longitudinal study focused on dairy heifer calves from birth to weaning; data were collected on 2,545 calves. The percentage morbidity for all calves enrolled in the study was 33.9%. Backward elimination model selection was used after univariate screening to determine which management practices and environmental factors significantly affected morbidity and mortality. The final morbidity model included birth weight, serum IgG concentration, ventilation type, and average temperature-humidity index (THI) during the preweaning period. After controlling for other independent variables in the model, calves born at a higher birth weight had a lower predicted risk of morbidity than calves with a lower birth weight. An increase in serum IgG concentration was associated with decreased morbidity. Calves housed in positive- or cross-ventilated systems had a 2.2 times higher odds of developing disease compared with calves housed in natural ventilation systems. Average THI during the preweaning period was inversely correlated with morbidity; as THI increased, the predicted morbidity risk decreased. The percent mortality for all calves enrolled in the study was 5.0%. The final mortality model included birth weight, serum IgG concentration, amount of fat/day in the liquid diet, and morbidity. After controlling for other independent variables in the model, calves born at a higher birth weight had a lower risk of mortality. An increase in serum IgG concentration decreased the risk of mortality. The odds of mortality were 3.1 times higher in calves fed ≤0.15 kg of fat/d in the liquid diet compared with calves fed ≥0.22 kg of fat/d. The odds of mortality were 4.7 times higher in calves that experienced any disease throughout the preweaning period than in calves with no disease. In summary, morbidity and mortality were both associated with birth weight and serum IgG concentration. Additionally, morbidity was associated with ventilation type and average monthly THI, and mortality was associated with amount of fat per day in the liquid diet and morbidity.

Long-term use of yeast fermentation products in comparison to halofuginone for the control of cryptosporidiosis in neonatal calves

“…In almost all calves the serum total protein concentration reached or exceeded the value of 55 g/l on day 4, regardless of the treatment group. This indicates a sufficient transfer of immunoglobulins by colostrum to calves (Weaver et al, 2000), which is principally necessary to protect calves from morbidity (Urie et al, 2018c). It was, therefore, not surprising that the serum total protein concentration was not correlated with the intensity of Cryptosporidium infection (measured by AUC values of oocyst shedding or coproantigen scores) or the number of days with diarrhea in this study.…”

Preweaned heifer management on US dairy operations: Part I. Descriptive characteristics of preweaned heifer raising practices

“…Thus, there is room to improve overall morbidity and mortality in preweaned dairy heifer calves. Refer to Urie et al (2018b) for a more in-depth discussion on preweaning dairy heifer health.…”

Bovine coronavirus in Uruguay: genetic diversity, risk factors and transboundary introductions from neighboring countries

“…NCD has a negative impact on animal welfare and leads to economic losses to the livestock industry due to the costs of treatment and prophylaxis, increased susceptibility to other diseases, increased mortality, and long-term residual effects, such as reduced growth rates and milk production [2][3][4][5]. Neonatal calf diarrhea is the major cause of death in unweaned heifers [6].…”