Analysis of severe feather pecking behavior in a high feather pecking selection line

Abstract Following mutagenesis with ethyl methanesulfonate, selection in a susceptible strain with a concentration of the insecticide diazinon (0.0004%, w/v) above that required to kill 100% of the susceptible strain, the LC100 of that strain, resulted in a single gene response. The resultant four mutant resistant strains have equivalent physiological, genetical and biochemical profiles to a diazinon-resistant strain derived from a natural population and homozygous for the Rop-1 allele. Modification of the microsomal esterase E3 is responsible for resistance in each case. The Rop-1 locus maps approximately 4.4 map units proximal to bu on chromosome IV. Selection within the susceptible distribution, at a concentration of diazinon [0.0001% (w/v)] less than the LC100, resulted in a similar phenotypic response irrespective of whether the base population had been mutagenized. The responses were polygenically based, unique to each selection line and independent of Rop-1. The relevance of the results to selection for insecticide resistance in laboratory and natural populations is discussed.

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Genetic and Molecular Analysis of smooth, a Quantitative Trait Locus Affecting Bristle Number in Drosophila melanogaster

Genetics ◽

10.1093/genetics/146.2.607 ◽

1997 ◽

Vol 146 (2) ◽

pp. 607-618

Author(s):

Petra zur Lage ◽

Antony D Shrimpton ◽

Andrew J Flavell ◽

Trudy F C Mackay ◽

Andrew J Leigh Brown

Keyword(s):

Quantitative Trait Locus ◽

Quantitative Trait ◽

Rna Binding ◽

Rna Binding Proteins ◽

Allelic Variation ◽

P Element ◽

Selection Line ◽

Element Insertion ◽

Bristle Number ◽

Trait Locus

A semi-lethal, sterile allele of the smooth locus (2-91.5), sm3, was discovered in an artificial selection line for low abdominal bristle number that had been started from a P-M dysgenic cross. The fitness effects and extremely low bristle number phenotype of the allele could not be separated by recombination from a P-element insertion at cytological location 56E, and precise excision of the P element at this site was associated with reversion to wild type. The smooth gene was cloned using the P-element insertion as a tag. The gene encodes a 2.6-kb transcript derived from 10 exons and covers a genomic region of at least 80 kb. The Drosophila smooth gene shares substantial sequence identity with a group of RNA binding proteins, with the closest relationship being to the human heterogeneous nuclear ribonucleoprotein L gene. The smooth gene is by definition an abdominal bristle number quantitative trait locus, but further work is required to discern whether naturally occurring allelic variation at this locus is a source of genetic variation for abdominal bristle number in natural populations.

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Is feather pecking in laying hens a by-product of artificial selection?

Applied Animal Behaviour Science ◽

10.1016/j.applanim.2009.12.007 ◽

2010 ◽

Vol 122 (2-4) ◽

pp. 133 ◽

Cited By ~ 2

Author(s):

Jeroen van Rooijen

Keyword(s):

Artificial Selection ◽

Laying Hens ◽

Feather Pecking

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Selection for components of efficient lean growth rate in pigs 2. Selection pressure applied and direct responses in a Landrace herd

Animal Science ◽

10.1017/s0003356100007753 ◽

1994 ◽

Vol 59 (2) ◽

pp. 263-269 ◽

Cited By ~ 9

Author(s):

N. D. Cameron ◽

M. K. Curran

Keyword(s):

Growth Rate ◽

Genetic Correlations ◽

Correlated Response ◽

Selection Line ◽

Control Line ◽

Direct Response ◽

Lean Growth ◽

Ad Libitum ◽

Selection For ◽

Ad Libitum Feeding

AbstractResponses to divergent selection for lean growth rate with ad-libitum feeding (LGA), for lean food conversion (LFC) and for daily food intake (DFI) in Landrace pigs were studied. Selection was practised for four generations with a generation interval ofl year. A total of 2642 pigs were performance tested in the high, low and control lines, with an average of 37 boars and 39 gilts performance tested per selection line in each generation. The average within-line inbreeding coefficient at generation four was equal to 0·04. There was one control line for the DFI and LFC selection groups and another control line for the LGA selection group. Animals were performance tested in individual pens with mean starting and finishing weights of 30 kg and 85 kg respectively with ad-libitum feeding. The selection criteria had phenotypic s.d. of 32, 29 and 274 units, for LGA, LFC and DFI, respectively, and results are presented in phenotypic s.d.Cumulative selection differentials (CSD) were 5·1, 4·5 and 5·5 phenotypic s.d. for LGA, LFC and DFI, respectively. Direct responses to selection were 1·4,1·1 and 0·9 (s.e. 0·20) for LGA, LFC and DFI. In each of the three selection groups, the CSD and direct responses to selection were symmetric about the control lines. The correlated response in LFC (1·1, s.e. 0·19) with selection on LGA was equal to the direct response in LFC. In contrast, the direct response in LGA was greater than the correlated response (0·7, s.e. 0·18) with selection on LFC. There was a negative correlated response in DFI (-0·6, s.e. 0·18) with selection on LFC, but the response with selection on LGA was not significant (0·2, s.e. 0·16).Heritabilities for LGA, LFC and DFI ivere 0·25, 0·25 and 0·18 (s.e. 0·03), when estimated by residual maximum likelihood, with common environmental effects of 0·12 (s.e. 0·02). Genetic correlations for LFC with LGA and DFI were respectively positive (0·87, s.e. 0·02) and negative (-0·36, s.e. 0·09), while the genetic correlation between DFI and LGA was not statistically different from zero, 0·13 (s.e. 0·10). Selection on components of efficient lean growth has identified LGA as an effective selection objective for improving both LGA and LFC, without a reduction in DFI.

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Feather pecking behavior in laying hens: Hypothalamic gene expression in birds performing and receiving pecks

Poultry Science ◽

10.3382/ps.2010-00961 ◽

2011 ◽

Vol 90 (6) ◽

pp. 1145-1152 ◽

Cited By ~ 35

Author(s):

E. Brunberg ◽

P. Jensen ◽

A. Isaksson ◽

L. Keeling

Keyword(s):

Gene Expression ◽

Laying Hens ◽

Feather Pecking

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Selection for lean growth rate and correlated responses in litter traits in a synthetic line of Yorkshire-Meishan pigs

Canadian Journal of Animal Science ◽

10.4141/a00-082 ◽

2001 ◽

Vol 81 (2) ◽

pp. 205-214 ◽

Cited By ~ 6

Author(s):

P. Chen ◽

T. J. Baas ◽

J. C. M. Dekkers ◽

L. L. Christian

Keyword(s):

Growth Rate ◽

Regression Coefficients ◽

Correlated Response ◽

Selection Line ◽

Control Line ◽

Correlated Responses ◽

Lean Growth ◽

Litter Traits ◽

Selection For ◽

Synthetic Line

Selection for lean growth rate (LGR) was conducted for four generations in a synthetic line of Yorkshire-Meishan pigs to study the effectiveness of selection for LGR and correlated responses in litter traits. Lean growth rate was estimated from ultrasound measurements of 10th-rib backfat thickness and longissimus muscle area. In the selection line, 7 boars and 20 gilts with the highest LGR were selected to produce the next generation. The generation interval was 13 mo and the average selection differential per generation was 1.1 phenotypic standard deviation units. A contemporaneous control line was maintained by randomly selecting 5 boars and 15 gilts. Data from a total of 1057 pigs sired by 58 boars and out of 133 sows were available from the two lines. Selection responses were estimated from deviations of the selection line from the control line using least squares (LS) and by multiple trait derivative-free restricted maximum likelihood analysis using an animal model (AM). The estimate of response to selection per generation using LS was 9.4 ± 0.95 g d–1 for LGR. The corresponding estimate from the AM was 9.8 ± 0.51 g d–1. Correlated responses in litter traits were regressed on generation. For the LS method, regression coefficients were negative but not significant (P > 0.05) for total number born, number born alive, and number at 21 d and at 42 d. Significant, positive correlated responses occurred in 42-d litter weight and 21-d piglet weight (P < 0.05). For the AM method, the regression coefficients were also negative, but were not significant (P > 0.05) for numberalive at birth, at 21 d, and at 42 d. A significant positive correlated response occurred only for 42-d litter weight (P < 0.05). Although results are based on a population of limited size, it can be concluded that selection for LGR in a synthetic line is effective and should have little effect on litter traits. Key words: Pigs, selection, lean growth rate, correlated response

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