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

Ante-Natal and Post-Natal Influences on Neonatal Immunity, Growth and Puberty of Calves—A Review

Calf immunity, growth and puberty are important factors affecting heifer productivity. The first four weeks of age are critical for reducing calf morbidity and mortality. It is well documented that colostrum is paramount to neonatal nutrition and passive immunity, however, adaptation to extra-uterine life starts early during embryonic development. Therefore, successful calf rearing strategies are underpinned by adequate maternal nutrition during gestation, and good colostrum management. A deeper understanding of these interactions paves the way for developing strategies to improve immune responses to environmental pathogens, optimal growth and timely attainment of puberty in calves. The literature reviewed here shows that there are opportunities to enhance the future performance of cattle paying attention to the interaction of nutrition and immunity at each developmental stage. Therefore, the objective of this review is to give the reader an overview of interactions between immunity, growth and puberty in dairy calves and highlight how these influence future performances.

Factors affecting rearing practices and health of calves on family farms

Aim of the study: Calf rearing practices vary in different countries and may be affected by many factors. Poor management is related to diseases outbreak and death in calves. This study aimed to analyze practices in calf rearing and the occurrence of common calf diseases on family farms in two European countries and to examine the characteristics of a farmer and his farm as factors that may affect the way of performing practices related to calves’ health.Area of study: Slovenia and Serbia.Material and methods: For collecting data, the same questionnaire-based survey was distributed among cattle farm owners in Slovenia and Serbia.Main results: The following factors showed a significant influence (p<0.05) on certain rearing practices: farm size (on time for checking calves, milk reheating, and providing rehydration fluids to the calf with diarrhea in Slovenia), specialization of the production (on preventive antiparasitic treatments and restriction of drinking water for calves with diarrhea in Slovenia, and the time for checking calves in Serbia), breeder’s age (on colostrum quality checking in Slovenia), and breeder’s education (on time for checking calves and checking colostrum quality in Serbia). The results pointed out the rearing practices to be improved in both countries, Slovenia and Serbia, such as colostrum management and prevention strategies of calf diseases.Research highlights: Characteristics of the farmer and his farm may affect many aspects of calves’ rearing. Continuous education of farmers and appropriate production planning can contribute to better farm productivity and better health and welfare of calves.