The Research Column

Bovine somatotropin (bST) or popularly referred to as growth hormone, is a naturally produced hormone which is a key regulator of growth and milk production.

Farm animals are now exposed to more heat-stress events due to an overall increase in global temperature than ever before, and the dairy industry is highly affected by climate change because Holstein cows, which comprise the vast majority of the global dairy population, are very sensitive to high temperatures. Heat-abatement technologies are often used on dairy farms to mitigate the effects of heat stress.

Milk, a staple in many diets worldwide, is often considered a nutritional powerhouse. Being rich in calcium, phosphorus, vitamin D, and high-quality protein, it plays a pivotal role in bone health, immune function, and overall well-being. Numerous studies have linked adequate milk consumption to a reduced risk of various chronic diseases, including osteoporosis, cardiovascular disease, and certain types of cancer.

Achieving high levels of pasture utilization by pasture-based dairy cattle are the cornerstone of profitable grazing systems. Whereas the productivity of such systems is often considered in terms of milk output per cow or per ha, milk production efficiency necessitates that individual animal milk production and pasture DMI are evaluated simultaneously.

The productive performance of first-lactation cows is a crucial indicator of their overall productive potential and health. This is also linked to milk production in subsequent lactations and the cow’s productive performance, longevity, and ability to live a long life.

Direct-fed microbials (DFM) defined as “live, naturally occurring microorganisms that have been used to improve digest

The urea nitrogen excreted by animals with their urine, which is subsequently degraded by the microbial enzyme urease, is a major source of ammonia emissions. In case of an imbalance between protein and energy supply in the feed, the surplus of ammonia is detoxified to urea in the liver and enters the bloodstream, where it diffuses or is transported to other fluid pools, such as milk or rumen liquid.

Research has shown that the dietary supplementation of specific branch-chain volatile fatty acids (BCVFA) (e.g., iso-butyrate, 2-methybutyrate, and iso-valerate), either individually or in combinations with another straight-chain FA, valerate (collectively known as isoacids; ISO), significantly improves cellulolytic bacterial grow

Bovaer or 3-Nitrooxypropanol (3-NOP) is an anti-methanogenic feed additive that inhibits a key enzyme involved in the last step of methane (CH4) production by the rumen methane-producing organisms.

The nitrogen use efficiency (NUE; defined as N output in milk/N consumed) of dairy cows within pasture-based systems is rather low, often less than 25%. Excreted N, in particular the rather high urinary N, may thus be lost to the atmosphere as ammonia and nitrous oxide and to waterways as nitrates.