The Research Column

In many pasture-based milk production systems, simple and productive forage systems have resulted in swards dominated by perennial ryegrass (Lolium perenne L.), as they show high productivity and nutritional value over a comparatively long growing season (Baker et al., 2023).

Oilseeds are a good source of fat and protein and often increase milk fat yield. Soybeans are a commonly used oilseed that can increase FCM and increase milk component yields at higher inclusion levels.

Transition milk, which is collected between the second and seventh milking after calving, during the transition from colostrum to normal milk, contains maternal leukocytes, growth hormones, cytokines, antimicrobial factors, and nutrients. It has been found to contain 15 immune system proteins, the concentrations of which gradually decrease during subsequent milkings.

It is generally accepted that by selecting for feed efficient cows, enteric methane emissions should be reduced, but there is currently not consensus on their relationship. Limited evidence does indicate that residual feed intake (RFI) is favourably correlated with enteric methane emissions throughout lactation.

Staphylococcal species are frequently isolated from milk samples of dairy cows. Among the 20 staphylococcal species commonly recovered, Staphylococcus aureus is the most studied.

As a methane-reducing feed additive, Bovaer or 3-nitrooxypropanol (3-NOP) is one of the most extensively researched additives. Numerous studies have demonstrated the efficacy of 3-NOP in reducing methane emissions.

Since the nineties, a combination of fluctuating and extreme prices of

Although the most common practice to house dairy calves individually for at least the first weeks of life, animal welfare concerns increasingly promote pre-weaning social housing systems. Housing dairy calves with social contact enables natural behaviours (e.g., social grooming and play), reduces fear and avoidance of novel environments, and is likely to provide affective benefits.

In cow-calf contact (CCC) systems, calves are allowed to have maternal contact until a later age than in conventional dairy production systems, where cow and calf are separated shortly after birth. Although CCC systems may vary in design, for example, dam-calf rearing versus foster cow rearing, or full CCC versus partial CCC.

Not all calves are needed as replacements in dairy herds; almost all male calves and any excess females can be termed ‘non-replacements’ (or ‘surplus’ or ‘excess’ calves). Globally, these calves are managed through one of three pathways: early life killing, raised for veal, or raised for beef.