scholarly journals Futteraufnahme und Fressverhalten wachsender Lämmer – 1. Mitteilung: Heritabilitäten und genetische Korrelationen

2008 ◽  
Vol 51 (4) ◽  
pp. 366-371 ◽  
Author(s):  
R. Wassmuth ◽  
E. Gernand ◽  
H. Lenz ◽  
C. Mendel

Abstract. Title: Feed intake and eating behaviour of growing lambs, 1st communication: heritabilities and genetic correlations In the test stations “Grub” (Bavaria) and “Schöndorf” (Thuringia) data were collected on lambs of the breeds Merinolandschaf and Merino Longwool. Feed intake during the whole test period (FAP), feed efficiency (FAW), daily feed intake (TFM), the number of daily visits (TBH) and eating time (TBD) of lambs were measured. In total, data from 1,608 lambs with 37,161 daily records in “Grub” and 1,424 lambs with 35,356 daily records in “Schöndorf” were included. The aim of the present study was to estimate heritabilities and genetic correlations for different traits of feed intake and eating behaviour. In “Schöndorf” the heritability of FAP and FAW was 0.29 and 0.32, respectively. In the test station “Grub” the heritability of the same traits was 0.58 and 0.57, respectively. The heritability of TBH, TBD and TFM were 0.33, 0.25 and 0.05, respectively, in “Schöndorf” and 0.49, 0.36 and 0.10, respectively, in “Grub”. The genetic correlations between the eating behaviour traits TBH and TBD on one hand and feed intake (FAP, FAW, TFM) on the other hand were low. It could be concluded that feed intake as well as eating behaviour showed considerable variances and heritabilities. Further, eating behaviour was not a good indicator of feed intake.

1996 ◽  
Vol 76 (1) ◽  
pp. 81-87 ◽  
Author(s):  
L. Q. Fan ◽  
J. W. Wilton ◽  
P. E. Colucci

Genetic parameters of feed intake and efficiency and production traits for lactating beef cows were estimated from data collected from 1980 to 1988 at the Elora Beef Research Centre, Guelph, Ontario. Estimates were obtained using restricted maximum likelihood (REML) with an individual animal model with year–season–treatment, sex of calf, parity, breeding system, covariate daily change of backfat depth and direct genetic and permanent environmental effects. The data included 1174 observations, 511 cows, 369 dam–maternal grand dam pairs and 245 sires of cows. Feed efficiency for milk was calculated as milk yield relative to energy consumed for milk and maintenance and residual feed consumption as estimated energy intake minus energy requirements as estimated by the National Research Council. Heritabilities for Herefords alone and total data, respectively, were estimated to be 0.02 and 0.11 for cow's daily ME intake (MEI), 0.26 and 0.26 for daily milk yield (DMY), 0.45 and 0.33 for milk fat percentage (MFP), 0.29 and 0.40 for metabolic body weight (MBW), 0.21 and 0.10 for calf weaning weight as a proportion of cow weight at weaning (PPW), 0.18 and 0.11 for feed efficiency for milk (FE), and 0.23 and 0.03 for residual feed consumption (RFC). Genetic correlations of output (DMY) and input (MEI) were 0.31 for Hereford and 0.75 for the total data. Genetic correlations of RFC with both output (DMY) and input (MEI) were low. Genetically, PPW was positively associated with FE and DMY and negatively associated with MBW. Key words: Genetic parameters, feed efficiency, lactation, beef cow


2000 ◽  
Vol 43 (6) ◽  
pp. 561-572
Author(s):  
R. Wassmuth ◽  
H. Alps

Abstract. Title ofthe paper: Recording of feed intake in stationary testing of potential AI bulls This study was performed in order to estimate correlations between feed intake, eating time and daily gain in young bulls and in order to estimate genetic parameters for feed intake in successive testing periods aiming at reduction of costs for testing. Data were collected from 269 Station tested potential AI bulls of German Holstein. In the testing period beginning with the 112th and ending with the 312 day of life, bulls consumed 5.1 kg roughage in 125 minutes per day and increased their weight by 1,300 g daily. The heritability of feed intake was 0.42, of eating behaviour 0.40 and of daily gain 0.62. Between feed intake and eating behaviour no relationship could be observed. Hence, an indirect measurement of feed intake is not possible. The high genetic correlation between feed intake and daily gain of 0.96 is no reason to replace feed intake recording because of a promising relationship between feed intake and health of dairy cows. Because of a delayed Start of 32 % of all tested bulls a shortening of the test period should be orientated to the last testing periods. In the last testing period, the heritability of feed intake was 0.65 and the genetic correlation between feed intake in the last and in the whole test period was high with 0.88. Hence, the test period could be shortened favouring intake measurements between 263rd and 312th day of life.


2008 ◽  
Vol 51 (4) ◽  
pp. 372-380
Author(s):  
E. Gernand ◽  
R. Wassmuth ◽  
H. Lenz ◽  
C. Mendel

Abstract. Title of the paper: Feed intake and eating behaviour of growing lambs. 2nd communication: genetic correlations between feed intake and performance traits In the present study genetic correlations between feed intake, feed efficiency and daily feed intake on one hand and fattening performance, carcass quality and fertility on the other hand were estimated. Data were collected in the test stations “Schöndorf”/Thuringia and in “Grub”/Bavaria as well as in stud book farms in Thuringia and Bavaria. Fattening performance and carcass quality were measured on 4,397 and 2,264 lambs, respectively, in Schöndorf and 1,292 lambs in Grub. The genetic correlation between feed efficiency and the number of lambs born alive (LGL) was in Thuringia rA = −0.35, but in Bavaria −0.03 only. Further, the genetic correlations between daily feed intake and LGL were different with 0.29 in Thuringia and −0.20 in Bavaria. But the standard errors of the estimates were high due to an insufficient genetic linkage between data from station testing (fattening performance, carcass quality) and from field testing (fertility). Therefore, the results have to be considered as tendencies. A high feed intake during the whole test period led to better daily gain. The genetic relationships between feed intake and carcass quality were indifferent. When using feed intake or efficiency for breeding value estimation and selection no basically problems have to be expected.


1999 ◽  
Vol 1999 ◽  
pp. 47-47
Author(s):  
R.M. Herd ◽  
S.C. Bishop

Net feed efficiency refers to variation in feed consumption between animals net of requirements for maintenance and production, and may be measured as residual feed intake (RFI). Because RFI is independent of liveweight (LW) and growth rate, selection for improved net feed efficiency is likely to reduce feed intake with little change in growth. The purpose of this study was to establish whether there exists genetic variation in RFI in young British Hereford bulls, and to determine the phenotypic and genetic correlations of RFI with key production traits.The data consisted of performance measurements on 540 bull progeny of 154 British Hereford sires, collected over ten 200-day postweaning performance tests conducted between 1979 and 1988. The traits analysed were food intake (FI), 200 to 400-day daily gain (ADG), 400-day weight (W400), predicted carcass lean content (LEAN), lean growth rate (LGR), food conversion ratio (FI/ADG) and lean FCR (LFCR; FI/(ADG x LEAN), described by Bishop (1992).


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 347-347
Author(s):  
Pourya Davoudi ◽  
Duy Ngoc Do ◽  
Guoyu Hu ◽  
Siavash Salek Ardestani ◽  
Younes Miar

Abstract Feed cost is the major input cost in the mink industry and thus improvement of feed efficiency through selection for high feed efficient mink is necessary for the mink farmers. The objective of this study was to estimate the heritability, phenotypic and genetic correlations for different feed efficiency measures, including final body weight (FBW), daily feed intake (DFI), average daily gain (ADG), feed conversion ratio (FCR) and residual feed intake (RFI). For this purpose, 1,088 American mink from the Canadian Center for Fur Animal Research at Dalhousie Faculty of Agriculture were recorded for daily feed intake and body weight from August 1 to November 14 in 2018 and 2019. The univariate models were used to test the significance of sex, birth year and color as fixed effects, and dam as a random effect. Genetic parameters were estimated via bivariate models using ASReml-R version 4. Estimates of heritabilities (±SE) were 0.41±0.10, 0.37±0.11, 0.33±0.14, 0.24±0.09 and 0.22±0.09 for FBW, DFI, ADG, FCR and RFI, respectively. The genetic correlation (±SE) was moderate to high between FCR and RFI (0.68±0.15) and between FCR and ADG (-0.86±0.06). In addition, RFI had low non-significant (P > 0.05) genetic correlations with ADG (0.04 ± 0.26) and BW (0.16 ± 0.24) but significant (P < 0.05) high genetic correlation with DFI (0.74 ± 0.11) indicating that selection for lower RFI will reduce feed intake without adverse effects on the animal size and growth rate. The results suggested that RFI can be implemented in genetic/genomic selection programs to reduce feed intake in the mink production system.


1999 ◽  
Vol 79 (4) ◽  
pp. 425-431 ◽  
Author(s):  
B. W. Kennedy ◽  
J. C. M. Dekkers ◽  
R. K. Moore ◽  
L. Jairath

Production and feed intake data on 36 115 first lactation Holstein cows obtained from Quebec Dairy Herd Analysis Service were combined with conformation data from the Holstein Association of Canada to estimate genetic correlations among production, energy intake, and conformation traits. Traits considered were 305-d milk yield, 305-d grain energy and total energy intake, feed efficiency (fat corrected milk yield/total energy intake), body weight at calving, capacity, size, stature, rump width and final score. Genetic and phenotypic parameters were estimated using Restricted Maximum Likelihood based on two-trait animal mixed model analyses. The model contained fixed effects of herd-year, season of calving, age of calving, sire group and a random animal genetic effect. Estimates of heritability were within the published range for all traits. Of the conformation traits examined, capacity, size and stature had the highest correlations with body weight, with phenotypic correlations between 0.36 and 0.43, and genetic correlations between 0.61 and 0.79. Feed efficiency was negatively correlated to all body size measures, both phenotypically (−0.01 to −0.29) and genetically (−0.31 to −0.53), but most significantly with body weight, capacity, size, and stature. Fat-corrected milk yield showed negligible phenotypic and low to moderately negative genetic (−0.07 to −0.29) correlations with body weight and related type traits. Total energy intake was positively related to all measures of body size, most notably body weight, while grain energy intake had moderately negative genetic correlations (−0.20 to −0.40) with the same body size traits. Because of their detrimental relationships with feed efficiency, negative selection emphasis should be placed on body weight and the related type traits capacity, size and stature. Capacity, size and stature are of moderate utility when selecting indirectly for body weight, total energy intake and feed efficiency. Key words: Dairy cattle, genetics, production, conformation, feed efficiency


Author(s):  
Hadi Esfandyari ◽  
Just Jensen

Abstract Rate of gain and feed efficiency are important traits in most breeding programs for growing farm animals. Rate of gain (GAIN) is usually expressed over a certain age period and feed efficiency is often expressed as residual feed intake (RFI), defined as observed feed intake (FI) minus expected feed intake based on live weight (WGT) and GAIN. However, the basic traits recorded are always WGT and FI and other traits are derived from these basic records. The aim of this study was to develop a procedure for simultaneous analysis of the basic records and then derive linear traits related to feed efficiency without retorting to any approximations. A bivariate longitudinal random regression model was employed on 13,791 individual longitudinal records of WGT and FI from 2,827 bulls of six different beef breeds tested for own performance in the period from 7 to 13 months of age. Genetic and permanent environmental covariance functions for curves of WGT and FI were estimated using Gibbs sampling. Genetic and permanent covariance functions for curves of GAIN were estimated from the first derivative of the function for WGT and finally the covariance functions were extended to curves for RFI, based on the conditional distribution of FI given WGT and GAIN. Furthermore, the covariance functions were extended to include GAIN and RFI defined over different periods of the performance test. These periods included the whole test period as normally used when predicting breeding values for GAIN and RFI for beef bulls. Based on the presented method, breeding values and genetic parameters for derived traits such as GAIN and RFI defined longitudinally or integrated over (parts of) of the test period can be obtained from a joint analysis of the basic records. The resulting covariance functions for WGT, FI, GAIN and RFI are usually singular but the method presented here do not suffer from the estimation problems associated with defining these traits individually before the genetic analysis. All results are thus estimated simultaneously, and the set of parameters are consistent.


2021 ◽  
Vol 12 ◽  
Author(s):  
Felipe M. W. Hickmann ◽  
José Braccini Neto ◽  
Luke M. Kramer ◽  
Yijian Huang ◽  
Kent A. Gray ◽  
...  

Porcine Reproductive and Respiratory Syndrome (PRRS) is historically the most economically important swine disease worldwide that severely affects the reproductive performance of sows. However, little is still known about the genetic basis of reproductive performance in purebred herds during a PRRS outbreak through the comparison of maternal and terminal breeds. Thus, the objective of this work was to explore the host genetics of response to PRRS in purebred sows from two breeds. Reproductive data included 2546 Duroc and 2522 Landrace litters from 894 and 813 purebred sows, respectively, which had high-density genotype data available (29,799 single nucleotide polymorphisms; SNPs). The data were split into pre-PRRS, PRRS, and post-PRRS phases based on standardized farrow-year-week estimates. Heritability estimates for reproductive traits were low to moderate (≤0.20) for Duroc and Landrace across PRRS phases. On the other hand, genetic correlations of reproductive traits between PRRS phases were overall moderate to high for both breeds. Several associations between MARC0034894, a candidate SNP for response to PRRS, with reproductive performance were identified (P-value < 0.05). Genomic analyses detected few QTL for reproductive performance across all phases, most explaining a small percentage of the additive genetic variance (≤8.2%, averaging 2.1%), indicating that these traits are highly polygenic. None of the identified QTL within a breed and trait overlapped between PRRS phases. Overall, our results indicate that Duroc sows are phenotypically more resilient to PRRS than Landrace sows, with a similar return to PRRS-free performance between breeds for most reproductive traits. Genomic prediction results indicate that genomic selection for improved reproductive performance under a PRRS outbreak is possible, especially in Landrace sows, by training markers using data from PRRS-challenged sows. On the other hand, the high genetic correlations with reproductive traits between PRRS phases suggest that selection for improved reproductive performance in a clean environment could improve performance during PRRS, but with limited efficiency due to their low heritability estimates. Thus, we hypothesize that an indicator trait that could be indirectly selected to increase the response to selection for these traits would be desirable and would also improve the reproductive performance of sows during a PRRS outbreak.


1988 ◽  
Vol 68 (3) ◽  
pp. 611-618
Author(s):  
L. N. IRWIN ◽  
G. W. FRIARS ◽  
R. J. JULIAN

A hierarchical mating of 25 sires and 192 dams produced 862 progeny that yielded complete records to market age in two hatches of broiler chickens. These progeny were housed in two levels of cages. Half of the birds were subjected to a compensatory feed treatment which was used as an indicator of appetite. Increased feed consumption, following fasting, resulted in increased deposition of abdominal fat. Various approaches were investigated with respect to maximizing the genetic improvement of feed efficiency. Estimates of the heritabilities of feed:gain, gain:feed, total feed intake, compensatory feed intake and compensatory gain were all low (0.24 or less), with generally high standard errors. The estimated heritabilities of gain and gain corrected for feed intake at 0.46 suggests that selection for the latter trait has potential for improving gain at a statistically fixed feed intake. The standard errors on estimates of genetic correlations were too wide to allow predicted selection changes in correlated traits, and thus these correlations were not presented. Key words: Broiler chickens, feed efficiency, compensatory feed intake, abdominal fat deposition


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