Results 241 to 250 of about 11,071 (289)
Some of the next articles are maybe not open access.
Livestock Science, 1999
Abstract Calving interval is currently used as the measure of reproductive performance in South Africa and many other countries, but some authors have claimed that calving interval is not a suitable measure of reproductive performance, when cows are mated during a restricted breeding season.
N H Casey
exaly +2 more sources
Abstract Calving interval is currently used as the measure of reproductive performance in South Africa and many other countries, but some authors have claimed that calving interval is not a suitable measure of reproductive performance, when cows are mated during a restricted breeding season.
N H Casey
exaly +2 more sources
The economics of calving intervals
Animal Science, 1979ABSTRACTA computerized mathematical model was used to test the economic effect of changing calving intervals under typical high-yielding (63701 per 305 days for mature cows) herd conditions at 1976 prices. The effect of month of first calving was also tested in a herd where four lactations are assumed to follow at equal calving intervals.Under the ...
A. D. James, R. J. Esslemont
openaire +1 more source
Calving Date versus Calving Interval as a Reproductive Measure in Beef Cattle
Journal of Animal Science, 1983Calving date and calving interval records obtained from the Beef Cattle Division of Pioneer Hi-Bred International, Des Moines, Iowa, were studied to determine the reproductive measure of choice when a fixed breeding season is employed. Fixed model, least-squares procedures were used to analyze 2,411 records collected on purebred Red Angus, Angus and ...
R M, Bourdon, J S, Brinks
openaire +2 more sources
Hematology reference intervals for neonatal Holstein calves
Research in Veterinary Science, 2018Data regarding hematologic reference intervals (RI) for neonatal calves have not been published yet. The aims of this study were: a) to establish hematology RIs for neonatal Holstein calves, b) to compare them with the RIs for lactating cows, and c) to investigate the relationship of age and gender with the hematologic profile of calves.
Nikolaos Panousis +5 more
openaire +2 more sources
Factors affecting the Relationship Between Calving Interval of Cows and Weaning Weights of Calves
Journal of Animal Science, 1986Characters related to production and reproduction were observed on 744 straightbred and F2 calves and their dams produced in a five-breed diallel with Angus, Brahman, Hereford, Holstein and Jersey breeds. These data were analyzed to estimate the effects of these characters on the relationship between weaning weight and calving interval.
P E, Doren, C R, Long, T C, Cartwright
openaire +2 more sources
Multivariate analysis of factors associated with calving interval and calving rate in dairy cows
Theriogenology, 1991We collected data on reproductive events of cows (n = 2116) that included dates of calving, first service, last artificial insemination before pregnancy examination, pregnancy examination, abortion, diagnosis of cystic ovary, and treatment with prostaglandin.
H O, Mohammed, M E, White, N, Lafaunce
openaire +2 more sources
Economic Consequences of Different Calving Intervals
Acta Agriculturae Scandinavica, 1989The study sought to answer the questions: when is the optimal time of conception for a given type of cow? and what is the economic cost of deviations from this optimum?
Erling Strandberg, Pascal A. Oltenacu
openaire +1 more source
Crossbreeding effects on milk yield traits and calving interval in spring‐calving dairy cows
Journal of Animal Breeding and Genetics, 2010SummaryThe aim of the study was to assess crossbreeding effects for 305‐day milk, fat, and protein yield and calving interval (CI) in Irish dairy cows (parities 1 to 5) calving in the spring from 2002 to 2006. Data included 188 927 records for production traits and 157 117 records for CI.
PENASA, MAURO +5 more
openaire +2 more sources
The length of the interval between calvings
The Journal of Agricultural Science, 1927An attempt has been made to ascertain the best interval between calvings, so that the cow's average weekly yield over a long period may be at a maximum. It was only possible to consider the case of the “average cow,” but it is claimed that the general principle has been established, that cows should calve at intervals of not less than a year, and not ...
openaire +1 more source
Marginal cost of the calving interval in beef cows is not uniform
Veterinary Record, 2018To understand the profitability of reproduction management measures, an economic assessment based on a beef cow life simulation was proposed. It accounted for the discounted feeding costs of the dam and its calves for the different periods of their lives up to their sale and for the overall production from calves adjusted by mortality and culling.
Raboisson, Didier, Citerne, Philippe
openaire +4 more sources