Associations between Feeding Behaviors Collected from an Automated Milk Feeder and Neonatal Calf Diarrhea in Group Housed Dairy Calves: A Case-Control Study

The objective of this case-control study was to determine if feeding behavior data collected from an automated milk feeder (AMF) could be used to predict neonatal calf diarrhea (NCD) in the days surrounding diagnosis in pre-weaned group housed dairy calves. Data were collected from two research farms in Ontario between 2017 and 2020 where calves fed using an AMF were health scored daily and feeding behavior data (milk intake (mL/d), drinking speed (mL/min), number of rewarded or unrewarded visits) was collected. Calves with NCD were pair matched to healthy controls (31 pairs) by farm, gender, and age at case diagnosis to assess for differences in feeding behavior between case and control calves. Calves were first diagnosed with NCD on day 0, and a NCD case was defined as calves with a fecal score of ≥2 for 2 consecutive days, where control calves remained healthy. Repeated measure mixed linear regression models were used to determine if there were differences between case and control calves in their daily AMF feeding behavior data in the days surrounding diagnosis of NCD (−3 to +5 days). Calves with NCD consumed less milk on day 0, day 1, day 3, day 4 and day 5 following diagnosis compared to control calves. Calves with NCD also had fewer rewarded visits to the AMF on day −1, and day 0 compared to control calves. However, while there was a NCD status x day interaction for unrewarded visits, there was only a tendency for differences between NCD and control calves on day 0. In this study, feeding behaviors were not clinically useful to make diagnosis of NCD due to insufficient diagnostic ability. However, feeding behaviors are a useful screening tool for producers to identify calves requiring further attention.

Comparison of enzyme-linked immunosorbent assay and Fassisi® bovine immunoglobulin G (IgG) immunoassay for quantification of bovine IgG in neonatal calf serum

Background and Aim: Rapid tests are routinely used to estimate serum immunoglobulin G (IgG) concentrations in diagnosing a failure of passive transfer (FPT) in calves. The study aimed to compare the Fassisi® Bovine IgG (FB-IgG) immunoassay and an enzyme-linked immunosorbent assay for quantifying bovine IgG in neonatal calf serum. Materials and Methods: A total of 277 calves of 1-10 days of age were used in this study. Blood samples were obtained, and serum was extracted by centrifuging the samples at 2740× g for 5 min at 20°C. The serum was analyzed using the FB-IgG according to the manufacturer's specifications. Serum IgG concentrations were also determined by enzyme-linked immunosorbent assay (ELISA-IgG). FPT was defined as a serum IgG concentration <10 mg/mL. Results: The mean ELISA-IgG serum concentration was 8.40 mg/mL (SD=7.02, range=0.10-47.50 mg/mL). FPT prevalence based on the ELISA measurements was 66.8%. The prevalence of partial and full FPT based on the FB-IgG was 54.5%. The ELISA-IgG and FB-IgG results were subjected to correlation and regression analysis. Overall sensitivity and specificity of the FB-IgG were 61.1% and 58.7%, respectively. A statistically significant dependence on age was identified in the results. Conclusion: Our findings suggest that the FB-IgG rapid method is less accurate and provides no other advantages over established methods.

A High Plane of Nutrition Is Associated with a Lower Risk for Neonatal Calf Diarrhea on Bavarian Dairy Farms

In all bovine production systems, neonatal calf diarrhea remains worldwide an important issue of economic losses and animal welfare. The aim of the present study was to identify risk factors for neonatal calf diarrhea as a herd health problem on Bavarian dairy farms. For the purpose of this study, management factors related to calf health were retrospectively compared between 59 dairy farms with calf diarrhea as a herd problem with those of 18 control farms, where no veterinary treatment of calves for neonatal calf diarrhea took place for at least one year prior to the farm visit. A multivariable binary logistic regression analysis of management factors indicated that administration of 3 L or more of colostrum at the second feeding after birth (Odds ration [OR] = 0.21, 95% confidence interval [95% CI] = 0.05–0.89), ad libitum feeding of milk during the first week of life (OR = 0.06, 95% CI = 0.006–0.60), and administration of an iron containing preparation after birth (OR = 10.9, 95% CI = 1.25–95.6) were independently associated with the presence of a herd problem with neonatal diarrhea. Results of this study therefore suggest that a higher plane of nutrition is a protective factor with regard to the occurrence of neonatal diarrhea on Bavarian dairy farms. These findings support the establishment of ad libitum feeding programs in dairy calf rearing.

Prevalence of Bovine Rotavirus and Coronavirus in Neonatal Calves in Dairy Farms of Addis Ababa, Ethiopia: Preliminary Study

Background. Bovine rotavirus (BRV) and bovine coronavirus (BCoV) are the most common viral agents in neonatal calf diarrhea and result in serious economic consequences. The aim of the study was to determine the epidemiology of those viruses in randomly selected dairy farms of Addis Ababa. Methods. A cross-sectional study was conducted from November 2018 to April 2019 using a probability proportional to size (PPS) sampling technique. A total of 110 calves, less than 30 days of age, from 57 dairy herds were involved in the study. Associated factors of herds and calves were collected using semistructured interviews from farm owners and through physical observation of selected calves. Fecal samples were collected and analyzed using the sandwich ELISA method. Data generated from both semistructured interviews and laboratory investigation were analyzed using STATA_MP version 15. Results. From the total 110 calves, 42 (38.18%) had diarrhea during the survey. The prevalence of bovine rotavirus and coronavirus was 3.64% (4/110) and 0.91% (1/110), respectively. Diarrhea, feeding colostrum timing, and sex of the neonatal calves had statistically significant association with bovine rotavirus infection ( p < 0.05 ). All rotavirus-positive neonatal calves were identified in small scale dairy farms and in dairy farms that reported mortality though they lack statistically significant association. Only one coronavirus case was detected among the neonatal calves. The case was identified among small scale herds and in a herd with diarrheal cases. The sex of the coronavirus calf was female, diarrheic, and among 11-20 days old. Conclusion. The prevalence of rotavirus and coronavirus infections in neonatal calves was seldom in dairy farms of the study area. Rotavirus was more common than coronavirus, and further studies should be initiated on other (infectious and noninfectious) causes of neonatal calf diarrhea in the area.

The Antibiotic Treatment of Calf Diarrhea in Four European Countries: A Survey

Neonatal calves are commonly affected by diarrhea caused by different pathogens, but not always bacteria. Yet, antibiotics are routinely used as a treatment to an unknown extent. It was our goal to survey antibiotic use for the treatment of neonatal calf diarrhea in different countries and to identify influencing factors. A total of 873 farmers and veterinarians in Austria, Belgium, Portugal, and Scotland participated in a voluntary online survey. The data were analyzed using classification and regression tree analyses and chi2 tests. Overall, 52.5% of the participants stated that they use antibiotics when treating neonatal calf diarrhea. Of those, 27% use them always, and 45% use highest priority critically important antibiotics. The most important factor differentiating antibiotic use practices was the country the participants were from, which could be due to regulatory differences between the countries. All antibiotic products stated were licensed for use in cattle, but several were not licensed for the treatment of diarrhea in calves. Our study shows that there is an urgent need for more scientific evidence to define best practices for the treatment of neonatal calf diarrhea. Furthermore, consensual criteria for antibiotic therapy must be defined, and targeted training for farmers and veterinarians must be provided.

Review on Common Infectious Diseases of Neonatal Calves

Neonatal calf mortality is one of the important problems of calf rearing in dairy farms worldwide. A successful dairy farm operation requires that a large percentage of cows wean a live healthy calf every year. However, in many developing countries, a large number of calves die during the early neonatal life, this causing heavy economic loss. This is due to several infectious (bacterial, viral, and protozoal) and non-infectious factors (management around birth, colostrum management, calf housing, feeding system, hygiene, and pathogens) play an important role in calf rearing. This paper aims to review major infectious causes of neonatal calf mortality. Numerous studies have been conducted in the past from many parts of the world using both retrospective and prospective data sources to document the major causes of calf mortality. Of the infectious diseases of calves, neonatal diarrhea is a matter of major concern, and multiple etiological agents from viruses (Bovine rotavirus, Bovine coronavirus, Bovine viral diarrhea virus) from bacteria (Salmonella spp, Escherichia-coli, and Clostridium perfringens) from protozoal (Cryptosporidium-parvum) have been identified as major causes of neonatal calf mortality. Among the infectious agents, rotavirus and E. coli are mainly involved in the causation of neonatal calf diarrhea which leads to high mortality and morbidity in young calves. E. coli mainly plays its role up to the second week of life whereas, rotavirus up to the third week. Generally, early calf mortality leading to economic losses due to the cost of treatment, prophylaxis, increased susceptibility to other infections, reduced growth rates, and death of calves. Keywords: Calf Mortality; Infectious Diseases; Diarrhea