Is Continued Genetic Improvement of Livestock Sustainable?

Hill, William G.

doi:10.1534/genetics.115.186650

Cited by 74 publications

(68 citation statements)

References 39 publications

(39 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, despite the success of the past 40 years it has been concluded that investment in family planning is needed to keep up with demand and meet the need of women who are unable to access services (see Population Council). Furthermore in a recent comment in the Lancet (World Abortions 1990to 2014, 2016 it was concluded that additional knowledge, regarding the incidence of induced abortion, is needed to motivate and inform efforts to help women avoid unintended pregnancies and to monitor progress toward that end. It was estimated that abortion rates have declined significantly since 1990 in the developed world, but not in the developing world.…”

Section: Population Growthmentioning

confidence: 99%

“…However it is important to realize that a more systems based approach to production will be required, together with the incorporation of new physiological and genetic technologies. Furthermore, despite large genetic improvements in the quantitative traits of growth, production, and efficiency of farmed livestock over recent decades, current evidence suggests that little variation has been lost and that improvements should indeed be sustainable in the future (Hill, 2016).…”

Section: Reproductive Technologies In the 21 St Centurymentioning

confidence: 99%

See 1 more Smart Citation

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Webb

Buratini

2016

Anim Reprod

View full text Add to dashboard Cite

show abstract

Section: Population Growthmentioning

confidence: 99%

Section: Reproductive Technologies In the 21 St Centurymentioning

confidence: 99%

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Webb

Buratini

2016

Anim Reprod

View full text Add to dashboard Cite

show abstract

“…This was highlighted by Swaggerty et al who reported that chicken genotypes which produce high levels of IL‐6, CXCLi2 and CCLi2 in response to Eimeria tenella infection have reduced lesional scores in the caeca. In Europe, although fast‐growing broiler genotypes are commonly used in poultry production, the use of slower‐growing genotypes is beginning to emerge . However, nothing has been reported regarding immune phenotypes in fast and slow growing broilers in response to Eimeria infection, which may determine whether fast or slow growing broilers may differ in their underlying resistance to Eimeria .…”

Section: Introductionmentioning

confidence: 99%

Differential immune response to Eimeria maxima infection in fast‐ and slow‐growing broiler genotypes

Giles

Sakkas

Belkhiri

et al. 2019

Parasite Immunology

View full text Add to dashboard Cite

Very little has been reported comparing resistance to coccidiosis in fast or slow growing broilers, the latter of which are becoming more prevalent in the broiler industry. We examined mRNA expression in the intestines of fast and slow growing broilers following Eimeria infection. We show that by day 13 post‐infection (d pi) with 2500 or 7000 oocysts of Eimeria maxima, slower‐growing (Ranger Classic) broilers significantly (P < 0.01) upregulated expression of proinflammatory cyclooxygenase genes (LTB4DH, PTSG1 and PTSG2) above that detected in fast growing (Ross 308) broilers. Expression of CD8α mRNA was downregulated in Ross 308 at day 6d pi with either 2500 or 7000 oocysts of E maxima (P < 0.05), compared to uninfected controls, but was not differentially expressed in Ranger Classic. CD4 genes were not differentially expressed in either chicken line infected with either infectious oocyst dose at d6 pi, compared to uninfected controls. However, at d13 pi, CD4 expression was significantly upregulated in both chicken lines infected with either infectious oocyst dose, compared to uninfected controls (P < 0.05) but this was significantly greater in Ranger Classic broilers compared to Ross 308 (P < 0.05). At d13 pi, expression of CD3 chains (required for T lymphocyte activation) was significantly increased in Ranger Classic compared to Ross 308, infected with either oocyst dose (P < 0.05‐0.01). Expression of IL‐2 and IL‐15 mRNA, required for T lymphocyte proliferation was also significantly upregulated, or maintained longer, in Ranger Classic broilers compared to Ross 308. These differences in immune response to E maxima corresponded with a reduction in E maxima genome detected in the intestines of Ranger Classic compared to Ross 308.

show abstract

“…In multigeneration selection programmes continued response has been seen, classically for over 100 generations in the Illinois maize kernel content lines, and there have been large and still continuing genetic improvements in livestock populations, notably in broiler chickens (Hill, ). Whilst the “obvious” source of continued response is mutation, some of the additive variation being utilized may have derived from the epistatic to additive conversion of founder and de novo variation.…”

Section: Introductionmentioning

confidence: 99%

“Conversion” of epistatic into additive genetic variance in finite populations and possible impact on long‐term selection response

Hill

2017

J Animal Breeding Genetics

View full text Add to dashboard Cite

SummaryThe role of epistasis in understanding the genetic architecture and variation of quantitative traits and its role, if any, in artificial selection and livestock improvement more generally has a long and sometimes controversial history. Its presence has been clearly demonstrated in, for example, laboratory experiments, but the amount of variation it contributes is likely to be small in outbred populations. In a finite population, although additive x additive epistatic variance is lost by genetic drift, it also contributes by conversion to additive variance through drift sampling and therefore has a potential indirect role in medium and long-term selection response, with superficial similarity to and hard to distinguish from mutation. Whilst predictions of response require knowledge of genetic parameters, an infinitesimal model provides some analytic results. Otherwise there is little quantitative information relevant to animal populations on which to judge this potential role of epistasis and reach firm conclusions.

show abstract

Is Continued Genetic Improvement of Livestock Sustainable?

Cited by 74 publications

References 39 publications

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Differential immune response to Eimeria maxima infection in fast‐ and slow‐growing broiler genotypes

“Conversion” of epistatic into additive genetic variance in finite populations and possible impact on long‐term selection response

Contact Info

Product

Resources

About