The Research Column

Feed efficiency is usually expressed as the amount of milk produced per unit of feed intake. However, this definition is a ratio trait, which is challenging to incorporate in selection indices. Residual feed intake (RFI) is an alternative expression of feed efficiency. It is defined as the difference between observed and predicted dry matter intake (DMI).

Soils underpin the requirements for health and longevity of mankind. They are critical, providing the basis of food production, a store and filter for water resources, the largest organic carbon store and a platform for development. Pressures on the soil resource grow as food demands rise and land degradation increases.

The foods we eat may have a direct impact on our cognitive acuity in our later years. This is the key finding of an Iowa State University research study by Dr B.S. Klinedinst and colleagues, published in the November 2020 issue of the Journal of Alzheimer's Disease, with reference: doi.org/10.3233/JAD201058. The title of the paper is: Genetic factors of Alzheimer’s Disease modulate how diet is associated with long term cognitive trajectories: A UK Biobank Study.

Reducing methane emissions in livestock production is one of the challenges of this century and researchers from different disciplines including nutrition, physiology, and genetics have made substantial efforts to develop tools that can help reduce methane emissions. Methane traits in dairy cattle have low to moderate heritability, from 0.11 to 0.33.

Lameness is the clinical condition of impaired locomotion and is caused by a range of foot and leg problems, the most common of which are hoof lesions caused by infectious agents or internal and external forces. It is a leading animal welfare concern in the dairy industry and also has substantive economic consequences, as productivity is decreased through reduced reproduction, milk production and increased culling. Various management practices for preventing lameness and treating lame cows have been developed. Despite this, lameness persists as an industry problem.

Ninety-nine farms were visited during the grazing period, and 85 farms were revisited during the housing period. At each visit, all lactating cows were scored for lameness (0 = good mobility, 1 = imperfect mobility, 2 = impaired mobility, 3 = severely impaired mobility), and potential herd-level risk factors were recorded through questionnaires and infrastructure measurements. Routine cow-level management data were also collected.