Dairy R&D in SA

Discipline: feeding; Keywords: PUFA, pregnancy, culling, BCS, digestibility, microbial protein

Research in the past 50 years has shown that the general health of dairy cows can be improved by higher post-ruminal delivery and absorption of poly-unsaturated fatty acids (PUFA), especially omega-3 (n-3) acid. Since flaxseed contains a high concentration of n-3, the objective of the authors cited below was to evaluate the effects of feeding the flaxseed-based supplement LinPro on the production and health of mid-to-late lactation multi-lactation Holstein cows.

Discipline: environment; Keywords: methane mitigation, SF6, temperate pasture, urea.

There is not much information on the effect of dietary nitrate addition as a method to mitigate methane in grazing dairy cows. Therefore, the authors cited below did a study aiming to investigate the effect of nitrate addition on daily enteric methane emissions, production performance and rumen fermentation of multi-lactation Jersey cows grazing perennial ryegrass pasture, which contained about 7.3 g nitrate per kg dry matter (DM).

Discipline: stress; Keywords: antioxidant herbs, anti-oxidative status, immunity, Jersey cows, milk yield.

Discipline: competitiveness; Key words: efficiency, market access, productivity, people, planet, management, education, commercialisation, environmental stewardship.

Competitiveness is a function of efficiency, market access (broadening of the market of dairy products is a primary goal) and sustainability. In addition to volatility, structural and consumer needs of markets which with up-to-date information can be addressed only partially, sustainability is progressively also influenced by issues which can be categorized within the three P concepts: Productivity (economic focus), People (sociological focus) and Planet (environmental stewardship focus). The priorities which have been identified and will form the nucleus of activities supported by Milk SA are the following:

Discipline: infection; Keywords: fasciolosis, Fasciola hepatica, lymnaied snail host, environment, molecular techniques, eDNA.

Discipline: calf rearing; Keywords: dry cow, dry period, nutrition, IgG, weight loss.

Weight loss of cows during the dry period has several consequences, mostly associated with reproduction and subsequent lactation. What is not generally considered is the success of colostrum production and its quality. This formed the basis of the study by the authors cited below.

Discipline: mastitis; Keywords: pathogens, intra-udder infection, TMR and PBS systems, Streptococcus uberis, coagulase negative Staphylococci.

Discipline: mastitis; Key words: bulk tank testing, bacteria counts, SCC, psychrotropic bacteria, cleanliness.

Routine bulk tank milk testing is an adjunct to monitor milk quality and udder health as total bacterial counts, and enumerating psychrotropic and thermoduric bacteria counts, may provide useful information on the cleanliness of milking procedures and equipment, the effectiveness of milk cooling and system sanitation. Also, differential bacterial counts may provide information on the occurrence of and changes in mastitis pathogens. The authors referenced below reported on the routine use of bulk tank testing from a study initiated from the Allerton State Laboratory in Pietermaritzburg.

Discipline: consumption; Keywords: communal areas, survey milk production, consumption, species, sour milk.

The production and consumption of milk in the communal areas of the Eastern Cape Province is largely unknown. Although production is expected to be modest, there should be potential in the sector for purposes of household and commercial milk production. Consumption trends in these communities, with a population size of roughly 4 million people, may influence general milk consumption trends in the country. The aim of the study by the authors referenced below was to collect baseline information which could inform future research. 

The Dairy Genomics Program (DGP) was initiated in 2016 with the primary aim to establish a reference population for dairy breeds which can be used to develop genomic estimated breeding values (GEBVs) which according to principle and function should improve the EBV’s , as calculated in the conventional way. The reference population (RP) was established in Phase 1 of the DGP which ended in March 2019 and the question was how did it benefit us. This was also the question posed by the authors cited below, who then did a GEBV analysis on Jersey cattle data and compared the GEBVs with previous EBV estimates. The Jerseys have been receiving BLUP (EBVs) and MACE breeding values for production, functional type, udder health, fertility and longevity traits for several years.