The use of appropriate method for genetic evaluation of dairy animals is an important aspect of dairy cattle production. Traditional 305-day lactation model does not account for the changes in environmental factors within 305-day lactation and may involve unjustified projection of incomplete lactations. The use of test-day model in the recent past has made it possible to economize the genetic e...

Dairy cattle are a primary reservoir of Coxiella burnetii, which causes Q fever. However, no recent nationwide studies have assessed the prevalence and risks of Q fever in dairy cattle. We report >or=94% prevalence in samples of bulk tank milk from U.S. dairy herds tested during the past 3 years.

Pasture-based dairy systems use grazing to supply significant percentages of the dry matter intake of cows and heifers. Such systems vary from those for which pasture is used only as a supplemental feed for cows primarily fed a total mixed ration to those for which pasture is the primary source of dry matter for the herd. Cows that are optimal in a pasture system share many general characterist...

AIMS To estimate prevalence and antimicrobial susceptibility of enterococci in faeces collected in 2007 from U.S. dairy cattle. METHODS AND RESULTS A total of 718 faecal samples from 122 dairy cattle operations from 17 US States were collected and cultured for the presence of enterococci. One hundred and eighteen of the 122 operations (96·7%) had at least one dairy cow positive for enterococc...

Manure application increases pasture crop production and minimizes manure storage costs. Excess N not absorbed by pasture vegetation can leach past the root zone and into ground water. A yearlong study was conducted on grazing pastures at 2 dairy farms to monitor potential nitrate (NO3) movement from the surface through the soil profile toward ground water. Precipitation, irrigation, manure app...

Ruminants, cloven-hoofed mammals of the order Artiodactyla, obtain their food by browsing or grazing, subsisting on plant material (Hungate, 1966). Today, 193 species of living ruminants exist in 6 families: Antilocapridae, Bovidae, Cervidae, Giraffidae, Moschidae and Tragulidae (Nowak, 1999). The number of wild ruminants is about 75 million and of domesticated about 3.6 billion (Hackmann and S...

The objective of this study was to determine whether dairy farms with poor cow welfare could be identified using a national database for bovine identification and registration that monitors cattle deaths and movements. The welfare of dairy cattle was assessed using the Welfare Quality(®) protocol (WQ) on 24 Portuguese dairy farms and on 1930 animals. Five farms were classified as having poor we...

The introduction of new technology, management practices, and alternative production systems has resulted in rapid structural change in the US dairy industry. This paper examines adoption rates and adopter characteristics for the following dairy technologies, practices, and systems: holding pen with an udder washer, milking units with automatic take-offs, genetic selection technologies, recombi...

The relative importance of livestock grazing in limiting or enhancing oak recruitment remains unclear because results from previous studies have been contradictory. In Santa Barbara County, we have replicated large-scale planting experiments from 1997 to 2001 to determine the effects of cattle and other factors on seedling establishment of valley oak (Quercus lobata) and coast live oak (Q. agri...

A narrative integrative review on the evidence for hoof trimming found 16 articles on efficacy, frequency, and associations with behavior and physiologic parameters. Review of these studies revealed (1) hoof trimming is associated with behavior and physiologic changes; (2) increasing the frequency of hoof trimming seems to decrease the incidence of hoof lesions; (3) there is limited research to...