In three consecutive years, spring-calving Hereford and Hereford x Angus cows (n = 348) were used to determine effects of level of supplemental energy or protein before and after calving on cowherd performance. Beginning on November 1, cows were individually fed 1.22 kg/d of a 40% CP (PROTEIN) or 2.44 kg/d of a 20% CP supplement (ENERGY) until calving. After calving, cows remained on the same s...

A total number of 1243 records of calving cases of 585 dairy Friesian cows during 8 consecutive years from 1997 to 2004 collected from Sakha Animal Production Research Station belonging to Animal Production Research Institute, Agriculture Research Center were used to study the effect of sire, live body weight (LBW) and age of dam and calving season on twinning rate and its consequent effects on...

Understanding spatiotemporal variability in prey accessibility is important for disentangling predator-prey interactions and is relevant to management interventions to reduce predation. Recently, caribou (Rangifer tarandus) in Newfoundland declined by 66%, with calf predation by black bears (Ursus americanus) implicated as a major proximate mechanism of the decline. Most predation occurs when c...

The search for ways to select for improved beef cow efficiency has become the holy grail of the beef cattle seedstock industry. Increases in beef production have often been possible due to enhancements in the reproduction indexes (e.g. calving frequency, age at first calving, calving interval), nutrition concepts (e.g. strategic supplementation, type of forage as well as quantity and quality), ...

A 4-yr study using 217 cows/yr (3/4 Red Angus, 1/4 Simmental) evaluated effects of calving date and wintering system on cow and calf performance from birth to harvest. Cows were assigned to 1 of 5 treatments: 1) March (Mar) calving cows wintered on native range, 2) Mar calving cows wintered on corn residue, 3) June (Jun) calving cows wintered on native range, 4) Jun calving cows wintered on cor...

Calving records collected between 2000 and 2008 at the Gudmundsen Sandhills Laboratory, Whitman, NE, were used to determine the effect of estrous synchronization on calving distribution and the impact of time of calving on carcass characteristics. Calves born between 2000 and 2006 resulted from non-synchronized 60 d breeding seasons between 1999 and 2005 (n = 2075). Calves born in 2007 and 2008...

At many marine-terminating glaciers, the breakup of mélange, a floating aggregation of sea ice and icebergs, has been accompanied by an increase in iceberg calving and ice mass loss. Previous studies have argued that mélange may suppress calving by exerting a buttressing force directly on the glacier terminus. In this study, I adapt a discrete element model to explicitly simulate mélange as a c...

Data on the reproductive traits of dairy heifers were analyzed using event-time techniques. Traits analyzed were age at first calving (n = 4631), days to first breeding, and days open (n = 1992) during the first lactation. A proportional hazard model was used that included fixed effects of herd-year, year-season, breed type, herd weight, and heifer weight. Body weights were recorded at 390 d of...

An increase in on-farm mortality (euthanasia and death) in dairy herds has been reported in several countries in the last decade. This does not only imply possible problems with animal welfare, but it also causes economic losses to the farmer. The objective of this study was to evaluate time trends in on-farm dairy cow mortality in Sweden and identify potential herd-level risk factors. Data wer...