The Research Column

by Heinz Meissner

Click on any of the publications below to read more about the specific topic:

 

Title Date Discipline Extract Keywords
Residual feed intake in peripartal dairy cows is associated with differences in milk fat yield, ruminal bacteria, biopolymer hydrolyzing enzymes, and circulating biomarkers of immunometabolism.

Studies evaluating RFI divergence between dairy cows have usually been performed during established lactation. Whether shortening the feeding period and increasing the number of cows would enhance the ability to detect physiological differences between the most efficient and  least efficient cows is largely unknown.

Effects of replacing inorganic salts of trace minerals with organic trace minerals in pre- and postpartum diets on feeding behaviour, rumen fermentation, and performance of dairy cows.

Pregnant cows and heifers (n = 273) were blocked by parity and body condition score and randomly assigned to either STM or OTM diets at 45 ± 3 days before their expected calving date. Both groups received the same diet, except for the source of trace minerals (TM). The STM group was supplemented with Co, Cu, Mn and Zn sulfates and Na selenite, whereas the OTM group was supplemented with Co, Cu, Mn and Zn proteinates and selenized yeast.

Effect of feeding fresh forage plantain (Plantago lanceolata) or ryegrass-based pasture on methane emissions, total-tract digestibility, and rumen fermentation of non-lactating dairy cows.

Methane emissions and rumen fermentation characteristics of the dairy cows fed 100% plantain (PLT) or 100% perennial ryegrass (RG; Lolium perenne) were measured in two experiments (E1 and E2). The forages were in a vegetative growth stage in E1 and were in a reproductive growth stage in E2. The CH4 emissions from 16 cows in each experiment were measured in respiration chambers for two days.

Potential effects of short- and long-term intake of fermented dairy products on prevention and control of type 2 diabetes mellitus.

The consumption of fermented dairy products is thought to potentially prevent or help to control type 2 diabetes mellitus (T2DM) through mechanisms of increased satiety, improved insulin sensitivity, increased glucose tolerance and maintenance of the gut microbiota. However, research results are inconsistent, and a recent meta-analysis of observational studies reported a neutral association between intake of fermented dairy and T2DM. The meta-analysis was limited by the lack of examination of the effect of fermented dairy consumption on diabetes prevention.

Predictors of diarrhea, mortality, and weight gain in male dairy calves.

The study used 2616 calves entering a calf-rearing facility for veal calves in Canada. The results nevertheless are considered relevant to rearing of heifer calves on farm. Faecal consistency scores were assigned twice daily for the first 28 days following arrival, where a score of 2, indicating runny consistency, and 3, indicating watery consistency, were classified as diarrhoea. Severe diarrhoea was classified by a score of 3. Serum total protein was measured upon arrival and the source of the calf (i.e., whether the calf came from a calf seller, local farm, or auction) was recorded.

Parents’ implicit perceptions of dairy milk and plant-based milk alternatives.

Milk consumption is motivated by both familiarity and habit and usually decreases with age. However, consumption during childhood and adolescence increases the chances of lifetime milk consumption. Understanding how parents perceive dairy milk and other dairy foods further enables development of dairy-positive messaging that aligns with their perceptions. The objective of the research by Dr A.N. Schiano and colleagues, done in North-Carolina, therefore was to understand parent belief systems around fluid dairy milk and plant-based alternatives (PBA).

Physical and economic performance of dairy cows managed within contrasting grassland-based milk production systems over 3 successive lactations.

In the study four milk production systems over three successive lactations and 20 cows per system during each lactation, were investigated. With winter calving-fully housed (WC-FH), Holstein cows were housed for the entire lactation and offered a complete diet consisting of grass silage, maize silage, and concentrates [approximately 50% forage on a dry matter (DM) basis].

A new method for producing superior set yogurt, focusing on heat treatment and homogenization.

In the study, the effects of homogenization conducted at higher pressure than the conventional (10 megapascal [MPa] for the first stage and 5 MPa for the second stage) on curd structure of set yogurt was investigated, the focus being on the fat globule size. Each yogurt mix was adjusted at the range of fat globule sizes from 0.45 μm to 1.1 μm by a homogenizer and then heated at 95°C for 5 minutes (conventional heat treatment), 120°C for 2 seconds (ESL processing) or 140°C for 2 seconds.

Economics of timed artificial insemination with unsorted or sexed semen in a high-producing, pasture-based dairy production system.

In the study the authors used a simulation model to estimate the potential economic benefit of using timed AI in combination with conventional unsorted or sexed semen in heifers only, and in both heifers and lactating cows. These scenarios were compared with a conventional reproductive programme in which heifers and cows were inseminated with conventional unsorted semen after oestrus detection (Control). A sensitivity analysis was also used to estimate the effect of hormone costs from timed AI use on the profitability of each programme relative to the conventional.

Cow- and herd-level risk factors for lameness in partly housed pasture-based dairy cows.

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.