Michael Laurence

This chapter is an overview of biosecurity in Australia as applied in beef cattle production. It covers protocols, notifiable diseases and risk assessment, and provides details of the resources needed to establish a sound, on-farm biosecurity protocol. The chapter also gives a summary of the beef cattle diseases that most affect productivity of cattle in Australia. This summary is not intended as a substitute for a veterinary textbook, but rather as a reference for tertiary students, producers, animal and agricultural scientists, farm consultants and veterinarians. Animal health is put into the context of the whole production system, emphasising understanding of the presentation and significance of cattle disease, prevention and treatment. A section at the end of the chapter covers basic cattle husbandry and handling. It describes some less traditional methods of handling and managing cattle as they might be applied in the context of Australian cattle production systems, highlighting the advantages of low-stress techniques. The chapter includes references for further reading, but does not purport to be a comprehensive review of this complex and ever-changing field of animal husbandry.

Beef cattle producers are concerned that selecting for carcass traits such as leanness, or for increased feed efficiency, might be deleterious to maternal efficiency and limit the use of genetic improvement technologies such as Estimated Breeding Values (EBVs). We define maternal efficiency by production parameters such as days to calving, birth weight, growth rate, weaning weight, as well as efficiency measures such as total intake and kg weaned per megajoule of metabolisable energy consumed per cow calf unit – kg weaned/MJ ME intake. Selecting for leanness in cattle is of economic benefit due to the relationship to higher yielding carcasses (Nkrumah et al., 2004). Net Feed Intake (NFI) is a trait used to measure feed efficiency in beef cattle, and is calculated as the actual amount of feed eaten by an individual animal less the expected amount of feed consumed based on the animal’s growth rate and body weight (Koch et al., 1963). Low NFI (high efficiency) is economically desirable due to the potential to reduce feed costs and increase stocking rates. Both traits affect the body condition of dams and this is closely linked to maternal traits in cattle (Morris on et al., 1999; Roche et al., 2000; Meikle et al., 2004). This experiment aims to quantify the impact on the breeder herd of selection for leanness or feed efficiency over three breeding cycles. The impact of level of nutrition was also assessed.