Dairy R&D in SA

Fasciola species are liver flukes that infect cattle and reduce the productivity by 15-30%. The infection can affect general health and feed intake that leads amongst others to morbidity, reduction in milk production and weight gains.

Mastitis results in large economic loss to both farmer and processor. In addition it has welfare implications for the cow and antimicrobial resistance concerns. Therefore, describing and analysing the measures used to prevent the disease and to minimize the losses remain important. For example, somatic cell count (SCC) directly affects revenue from the sale of milk and in one of the investigations the revenue loss was studied.   

Conception and re-conception rates of high-producing dairy cows remain of concern in dairy production systems, especially in the subtropics. Apart from the major effects of nutrition and specific nutrients on reproduction, other risk factors such as negative energy balance, inflammation and impairment of the immune response have been shown to affect re-conception rates. Dietary energy levels interact with blood urea nitrogen (BUN) and may influence the pregnancy rates of dairy cows.

Profitable milk production and genetic improvement in dairy herds depend largely on fertile cows calving annually to initiate a new lactation period. Over the last 30 years, several studies have indicated a decline in the reproductive performance of dairy cows. From the perspectives of many farmers and veterinarians, the reproductive performance of cows is related to the calving interval and services per conception.

Discipline: grazing/pastures; 

Discipline: genetic evaluation; 

Discipline: nutrition/feeding; 

Discipline: calf raising; 

Discipline: Genetic parameters/QTL’s;

Discipline: disease;