scholarly journals Development of animal breeding research.

1986 ◽  
Vol 34 (3) ◽  
pp. 421-426
Author(s):  
R.D. Politiek

This article outlines the scope of research on the genetic improvement of farm livestock in the Netherlands, and briefly describes the main current projects in the breeding of beef and dairy cattle. (Abstract retrieved from CAB Abstracts by CABI’s permission)

1953 ◽  
Vol 1953 (2) ◽  
pp. 76-85
Author(s):  
J. W. B. King

Since 1948 the Animal Breeding Research Organisation has been collecting twin cattle in the West Midlands of England. The dairy cattle population here is dense—an important factor in reducing cost of collection. Propaganda was issued in various forms all directed at getting in touch with farmers owning one-egg twins, i.e. twins originating from the splitting of a single fertilised egg as distinct from two-egg twins coming from two fertilised eggs. As the twinning rate in cattle is only 1-2% of all births, and probably only about 1 in 20 of these twins are one-egg, their purchase and collection under British conditions is rather costly. Up to the end of 1952, 103 pairs of one-egg heifers twins had been collected.


2012 ◽  
Vol 18 (7) ◽  
Author(s):  
Armin R.W. Elbers ◽  
Willie L.A. Loeffen ◽  
Sjaak Quak ◽  
Els de Boer-Luijtze ◽  
Arco N. van der Spek ◽  
...  

1980 ◽  
Vol 30 (2) ◽  
pp. 261-269 ◽  
Author(s):  
T. G. Martin ◽  
D. I. Sales ◽  
C. Smith ◽  
D. Nicholson

ABSTRACTData on 2120 lambs produced over 7 years in the Animal Breeding Research Organization synthetic Dam Line (49% Finn, 22% East Friesian, 16 % Border Leicester and 13 % Dorset Horn) were analysed by least squares. The effects of sex, age of dam, year of birth, birthrearing class, and age of lamb on weights at birth and at 4, 8, 12 and 16 weeks of age were all appreciable. However, pooled within-year correction factors should be adequate in adjusting records for selection. Heritability estimates for weights at the five ages ranged from 0·17 to 0·24 by the sire component method and from 0·18 to 0·28 by regression of offspring on dam. Previous reports of differences in heritability in singles and in twins were not confirmed. Estimates of the genetic correlations among the various lamb weights were high (0·62 to 1·04) indicating that selection for weight at one age should result in increased weights at all ages.


1980 ◽  
Vol 60 (2) ◽  
pp. 253-264 ◽  
Author(s):  
A. J. McALLISTER

In the last decade the dairy cattle population has declined to a level of 1.9 million cows in 1978 with about 56% of these cows bred AI and nearly 20% of the population enrolled in a supervised milk recording program. The decline in cow numbers has been accompanied by an increase in herd size and production per cow. The current breeding program of the dairy industry is a composite of breeding decisions made by AI organizations, breeders who produce young bulls for sampling and all dairymen who choose the sires and dams of their replacement heifers. Estimates of genetic trend from 1958–1975 for milk production in the national milk recorded herd range from 21 to 55 kg per year for the four dairy breeds with Holsteins being 41 kg per year. Both differential use of superior proven sires and improved genetic merit of young bulls entering AI studs contribute to this genetic improvement. Various national production and marketing alternatives were examined. Selection is a major breeding tool in establishing a breeding program to meet national production requirements for milk and milk products once the selection goal is defined. AI and young sire sampling programs will continue to be the primary vehicle for genetic improvement through selection regardless of the selection goal. The current resources of milk-recorded cows bred AI is not being fully utilized to achieve maximum genetic progress possible from young sire sampling indicate that the number of young bulls sampled annually in the Holstein breed could be tripled with the existing milk-recorded and AI bred dairy cow population. Expanded milk recording and AI breeding levels could increase the potential for even further genetic improvement. The potential impact of selection for other traits, crossbreeding and the use of embryo transfer of future breeding programs is highlighted.


Author(s):  
Geoff Simm ◽  
Geoff Pollott ◽  
Raphael Mrode ◽  
Ross Houston ◽  
Karen Marshall

Abstract This chapter discussed the effects of applying the different principles in animal breeding such genetic analysis, predicting breeding values, use of tools and breeding technology, selection response within breeds, and strategies for genetic improvements in dairy cattle.


Author(s):  
Anne-Marie Neeteson ◽  
Santiago Avendaño ◽  
Alfons Koerhuis

Abstract Animal breeding for welfare and sustainability requires improving and optimizing environmental impact, productivity, robustness and welfare. Breeding is a long-term exercise at the start of the food chain with permanent cumulative outcomes, disseminated widely. This chapter explains, with a focus on poultry, breeding programme design and how broadening breeding goals and managing trait antagonism results in balanced breeding and more robust animal populations. Breeding progress in skeleton and skin health, physiology and body composition, and behaviour are addressed. The economic impact of welfare and environmental improvements is worked out, and the ethical and societal aspects of genetic improvement are put into perspective. The consideration of feedbacks of all stakeholders, including customers and the wider society, is crucial. For each crossbreed, breeders will continue to improve overall welfare, health, productivity and environmental impact, but between the crossbreeds there will be clear differences answering specific demands of concepts and brands.


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