Perennial ryegrass is the most abundant grass species in temperate climates. An increased herbage intake of dairy cows by breeding new cultivars could have a large potential impact on agriculture. The effects of cultivars on sward structure, nutritive value, physical characteristics and disease resistance of perennial ryegrass are discussed. Cultivar differences were found in several studies fo...

A quantitative analysis of the potential benefits of using in v/?ro-produced embryos and embryo transfer (IVP and ET) technologies for beef production from spring-calving dairy herds is presented. The study was conducted using computer simulation. Additional profit was assessed from the production of high quality 4-day-old calves for the beef industry, which are derived from surplus dairy indus...

This study investigated the presence of aflatoxin M1 (AfM1) in dairy cows' milk, given predefined scenarios for milk production, compound feed (CF) contamination with aflatoxin B1 (AfB1), and inclusion rates of ingredients, using Monte Carlo simulation modelling. The model simulated a typical dairy farm in the Netherlands. Six different scenarios were considered, based on two lactation and thre...

The efficiency of feed utilization on dairy farms can be influenced by a variety of practices that are beyond the scope of this paper, including many aspects of the harvesting, storage, mixing, and delivery of feed components, as well as the grouping of animals according to nutritional needs. Two practices that will be addressed are: 1) improvement of the biological efficiency of lactating cows...

It has been proposed that livestock production effluents such as wastewater, airborne dust and manure increase the density of antimicrobial resistant bacteria and genes in the environment. The public health risk posed by this proposed outcome has been difficult to quantify using traditional microbiological approaches. We utilized shotgun metagenomics to provide a first description of the resist...

the base of this review is to consider the relevant role that animal factors (potential milk yield, body weight, body condition score, state of lactation, parity and fertility) play on milk performance (considering the energy balance and the rumen function across the full lactation curve of animals) and milk quality (milk protein content, milk fat content, milk lactose content, vitamins, minera...

Heat stress (HS) negatively affects various industries that rely on animal husbandry, particularly the dairy industry. A better understanding of metabolic responses in HS dairy cows is necessary to elucidate the physiological mechanisms of HS and offer a new perspective for future research. In this paper, we review the current knowledge of responses of body metabolism (lipid, carbohydrate, and ...

The dairy industry in North America has changed dramatically with a trend in direction of larger herds and higher production per cow, which seems to be associated with a decrease in fertility, especially a decrease in conception rates and extension of calving intervals (Butler, 2000; Lucy, 2001; Stevenson, 2001) This decline in fertility of lactating dairy cows is observed not only in North Ame...

Starter cultures are those microorganisms (bacteria, yeasts, and molds or their combinations) that initiate and carry out the desired fermentation essential in manufacturing cheese and fermented dairy products such as Dahi, Lassi, Yogurt, Sour cream, Kefir, and Koumiss amongst others. Starter culture is defined as “an active microbial preparation, deliberately added to initiate desirable change...

Silage accounts for 30 to 40% of the diet of dairy cattle in over 90% of the dairies in the Southeast. Corn silage is the main silage fed to dairy cattle in Florida and it plays a vital role in supplying digestible fiber and energy to dairy cows. The fiber supply from corn silage is also necessary for stimulating salivation and buffering microbial acid production in the rumen, thereby minimizin...