Observed and Theoretical Genetic Trends in a Large Dairy Population Under Intensive Selection

Burnside, E. B.; Jansen, G.B.; Civati, G.; Dadati, E.

doi:10.3168/jds.s0022-0302(92)77985-5

Cited by 32 publications

(20 citation statements)

References 9 publications

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“…Their figures were 68 kg, 49 kg and 1 % for milk yield, FCM and fat per cent respectively. BURNSIDE et al (1992) using data of Italian Holsteins, also reported higher gains per year, which were comparable to those obtained by MAKUZA and McDANIEL (1997). HALLO WELL et al (1998) reported annual genetic gains of 19 kg in first lactation cows in the South African Ayrshire cows.…”

Section: Resultssupporting

confidence: 76%

Genetic trends for milk, fat and protein in the Zimbabwean Holstein-Friesian population from 1973 to 1994

.¹,

Makuza

Wollny

et al. 2001

Arch. Anim. Breed.

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SummaryGenetic trends based on 30 395 records with parities 1 to 8 were estimated using average information restricted maximum likelihood algorithm (AIREML), which had overall mean, herd, month of calving, year of birth, parity and linear and quadratic effects of days in milk. Due to changes in the Zimbabwean milk recording system data set was split into records of cows born from 1973 to 1989 and the other from 1987 to 1994. The first data set was further split into even numbered herds (EVNH73) and odd numbered herds (ODNH73), due to computational limitations. The highest milk production was from May to August. Peak milk production was observed in parity 4. The heritabilities for FCM (0.22 to 0.26), fat percent (0.24 to 0.28) and protein percent (0.21) were comparable to literature values. The annual genetic trends of FCM ranged from 8.36 kg to 13.2 kg, fat per cent ranged from 0.0 % to -0.008 % and protein per cent was -0.003 % in the three data sets. Genetic trends for milk yield, fat and protein yield were also positive but overally lower than in most other countries. The positive genetic trends obtained for milk, fat and protein yields imply that some progress has been made in increasing the milk production despite the relatively small population and significant restrictions. There is need to develop a selection index to improve milk yield and milk composition.

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Section: Resultssupporting

confidence: 76%

Genetic trends for milk, fat and protein in the Zimbabwean Holstein-Friesian population from 1973 to 1994

.¹,

Makuza

Wollny

et al. 2001

Arch. Anim. Breed.

View full text Add to dashboard Cite

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“…The herd book managed by the IHF Cattle Breeders Association (ANAFI, Cremona, Italy) was established in 1959. In 1985 a breeding scheme based on progeny testing and a selection index giving large emphasis on fat (FY) and protein (PY) yields were defined (Burnside et al, 1992). Selection index has undergone several changes during the years, and the current one combines production, functional and type traits (ANAFI, 2011).…”

Section: Introductionmentioning

confidence: 99%

Genetic response for milk production traits, somatic cell score, acidity and coagulation properties in Italian Holstein–Friesian population under current and alternative selection indices and breeding objectives

et al. 2012

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“…Using additional information on the mares available for selection, the accuracy can rise substantially (scenario II). This is important because the costs for the ET technique are high; and therefore, only very good mares with high accuracies ought to be used as donor mares, as is the case in dairy cattle breeding for bull dams (Burnside et al 1992). The total costs for the breeding programme in scenario II are only marginally higher than in scenario I.…”

Section: Discussionmentioning

confidence: 99%

The potential of embryo transfer in a German horse‐breeding programme

Sitzenstock

Rathke

Ytournel

et al. 2012

J Animal Breeding Genetics

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A reference horse-breeding programme with 13500 foals each year was modelled with ZPLAN+. This new software for the optimization of the structures in breeding programmes is based on ZPLAN. In two scenarios, the implementation of a rigorous selection of mares was implemented. In scenario I, the mare performance test was the point of selection, while in scenario II, further information on 20 competitions in two more years is available. These selected mares were used for embryo transfer (ET), partly in combination with multiple ovulation (MOET). The selection intensity and the number of foals out of (MO)ET were varied in both scenarios. It was expected that 250, 500 and 1000 mares are available for selecting 20, 50, 100 or 200 donor mares each year. The number of foals out of (MO)ET was varied between one and six foals per donor mare and year. Donor mares were used for ET for 4 years. It became clear that with high selection intensities of donor mares and high reproduction rates of them, the yearly genetic gain in a horse-breeding programme could increase over a large range. In scenario II, the additional information on 20 competitions increased the accuracy of the selection index to 0.85. With 200 selected donor mares of 1000 available mares and six foals per year, the genetic gain could almost be doubled compared to the reference scenario. The implementation of ET and a related higher usage of few selected mares entails rising costs and a reduction in the genetic variance. In the most extreme MOET scenario, the effective population size was reduced by 19% relative to the reference scenario. Only if the increase in genetic gain can be converted into higher return for the breeders, the implementation of (MO)ET schemes is a realistic and sensible option for horse-breeding programmes.

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Observed and Theoretical Genetic Trends in a Large Dairy Population Under Intensive Selection

Cited by 32 publications

References 9 publications

Genetic trends for milk, fat and protein in the Zimbabwean Holstein-Friesian population from 1973 to 1994

Genetic trends for milk, fat and protein in the Zimbabwean Holstein-Friesian population from 1973 to 1994

Genetic response for milk production traits, somatic cell score, acidity and coagulation properties in Italian Holstein–Friesian population under current and alternative selection indices and breeding objectives

The potential of embryo transfer in a German horse‐breeding programme

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