scholarly journals Short-term selection for yearling weight in a small-experimental Iranian Afshari sheep flock

2009 ◽  
Vol 89 (3) ◽  
pp. 301-307 ◽  
Author(s):  
Farhad Ghafouri-Kesbi ◽  
Moradpasha Eskandarinasab ◽  
Ahmad Hassanabadi
Keyword(s):  
Animal Model ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Live Weight ◽  
Breeding Program ◽  
Sheep Flock ◽  
Breeding Values ◽  
Generation Interval ◽  
Selection For ◽  
Daily Gain

A selection experiment was initiated in 2000 in an Afshari sheep flock at the department of animal breeding and genetics of the University of Zanjan, Iran. The aim was to evaluate the response of Afshari sheep to selection for yearling live weight. Here, we evaluate the results of this breeding program obtained between 2000 and 2005. Traits studied were birth weight (BW), weaning weight (WW), yearling weight (YW), average daily gain from birth to weaning (WWDG) and average daily gain from weaning to yearling age (YWDG). Mixed model methodology based on a multi-trait animal model was employed to estimate (co)variance components and corresponding genetic parameters. Estimates of breeding values were obtained by the best linear unbiased prediction (BLUP) method. Generation intervals on the four genetic pathways were estimated as the average age of parents at the birth of their progeny kept for reproduction. The heritability estimates were 0.34, 0.27, 0.14, 0.20 and 0.01 for BW, WW, YW, WWDG and YWDG, respectively. Estimates of genetic correlations among traits studied were positive, and ranged from low (0.07, YW/WWDG) to high (0.76, YW/YWDG). Genetic improvements over the experiment based on estimated breeding values were 0.104, 0.824, 1.247, 0.005 and ≈0.00 kg for BW, WW, YW, WWDG and YWDG, respectively. Annual genetic gain for YW was relatively high, 0.311 kg yr-1, which demonstrated the effectiveness of the implemented breeding program. Correlated responses in BW, WW, WWDG and YWDG were 0.021, 0.167, 0.001 and ≈0.00 kg yr-1, respectively. Estimates of heritabilities and observed genetic trends indicated that selective breeding can lead to significant genetic improvement in Afshari sheep. The average generation interval was estimated to be 3.35 yr. The shorter generation interval was observed on the sire side compared with the dam side (3.30 yr vs. 3.78 yr), indicating faster generation turnover for sires than for dams. Key words: Sheep, animal model, genetic trend, generation interval, heritability

scholarly journals Genetic parameters and predicted response to selection for lean growth in an Australian commercial nucleus pig herd

2000 ◽  
Vol 51 (7) ◽  
pp. 833 ◽  
Author(s):  
Nguyen Hong Nguyen ◽  
Cam P. McPhee ◽  
Claire M. Wade ◽  
Brian G. Luxford
Keyword(s):  
Growth Rate ◽  
Genetic Parameters ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Genetic Response ◽  
Lean Growth ◽  
Derivative Free ◽  
Total Data ◽  
Selection For ◽  
Daily Gain

Genetic parameters for performance traits in a pig population were estimated using a multi-trait derivative-free REML algorithm. The 2590 total data included 922 restrictively fed male and 1668 ad libitum fed female records. Estimates of heritability (standard error in parentheses) were 0.25 (0.03), 0.15 (0.03), and 0.30 (0.05) for lifetime daily gain, test daily gain, and P2-fat depth in males, respectively; and 0.27 (0.04) and 0.38 (0.05) for average daily gain and P2-fat depth in females, respectively. The genetic correlation between P2-fat depth and test daily gain in males was –0.17 (0.06) and between P2-fat and lifetime average daily gain in females 0.44 (0.09). Genetic correlations between sexes were 0.71 (0.11) for average daily gain and –0.30 (0.10) for P2-fat depth. Genetic response per standard deviation of selection on an index combining all traits was predicted at $AU120 per sow per year. Responses in daily gain and backfat were expected to be higher when using only male selection than when using only female selection. Selection for growth rate in males will improve growth rate and carcass leanness simultaneously.

Effectiveness of selection for growth rate in Zebu × British crossbred cattle. II.* Post-weaning growth and genetic estimates

1975 ◽  
Vol 26 (6) ◽  
pp. 1093 ◽  
Author(s):  
GW Seifert
Keyword(s):  
Growth Rate ◽  
Birth Weight ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Female Offspring ◽  
High Birth Weight ◽  
Environmental Correlations ◽  
Final Weight ◽  
Selection For ◽  
Daily Gain

The response to one generation of selection for weight per day of age at 18 months (W/Af), in Africander cross (AX) and Brahman cross (BX) cattle, was evaluated in the female offspring of the up and down selected parents. The high W/A< line gained significantly more than the low line over a year from weaning. The advantage of the high W/A line occurred during flush nutritional periods. The realized heritability (h2) of W/Af at 18 months was 0.52, while the estimates of h2 from mid-parental means computed within sires was higher. Heritability estimates for birth weight (Wb), weaning weight per day of age (W/Aw), pre-weaning average daily gain (Gbw) and total average daily gain from birth to final weight (Gt) were all high, while the estimate for post-weaning average daily gain from weaning to final weight (Gpw) was low. The correlated responses of all the traits were high. The genetic correlations estimated from the response and the parent-offspring regressions were all positive and high. Birth weight was the most highly correlated with Gt. All phenotypic correlations were positive but lower than the genetic correlations, the correlation between Gbw and Gpw being the lowest. Environmental correlations between birth weight and pre-weaning traits were essentially zero, and between birth weight and post-weaning traits and Gt, negative. Weight per day of age at 18 months appeared to be the most efficient and practical single trait to select beef cattle for increased growth rate.

scholarly journals Genetic parameters for a joint genetic evaluation of production and reproduction traits in pigs

2011 ◽  
Vol 50 (No. 3) ◽  
pp. 96-103 ◽  
Author(s):  
J. Wolf ◽  
E. Žáková ◽  
E. Groeneveld
Keyword(s):  
Genetic Parameters ◽  
Performance Test ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Covariance Structure ◽  
Live Weight ◽  
Genetic Evaluation ◽  
Large White ◽  
Reproduction Traits ◽  
Daily Gain

The covariance structure was estimated by REML for a joint genetic evaluation of production and reproduction traits for Czech Landrace (58 258 records) and Czech Large White (167 161 records) pigs using four-trait animal models. The following traits were analysed: lean mean percentage at the end of the performance test in the field, estimated from ultrasonic measurements unadjusted for live weight (LM), average daily gain in field test (in g/day) calculated as weight at the end of the test divided by age at the end of the test (ADG), number of piglets born alive in parity 1 (NBA1) and number of piglets born alive in parity 2 and subsequent parities (NBA2+). The heritabilities were in the range from 0.30 to 0.37 for LM, from 0.13 to 0.18 for ADG, from 0.09 to 0.13 for NBA1 and from 0.10 to 0.14 for NBA2+, depending on the breed and on the model (herd-year-season random or fixed). Genetic correlations between production and reproduction traits were estimated to be non-zero. Correlations between traits caused by the herd-year-season effect were mostly positive. As a general conclusion, the joint genetic evaluation of production and reproduction traits is recommended. The herd-year-season effect should be preferably considered as random. &nbsp;

49 Predicting Breeding Values of Purebred Pigs for Crossbred Performance Using Crossbred Phenotypes and Genotypes

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 23-23
Author(s):  
Natalia Leite ◽  
Ching-Yi Chen ◽  
Willian O Herring ◽  
Shogo Tsuruta ◽  
Daniela Lourenco
Keyword(s):  
Quality Control ◽  
Animal Model ◽  
Average Daily Gain ◽  
Snp Markers ◽  
Single Step ◽  
Low Density ◽  
Genomic Information ◽  
Breeding Values ◽  
Partial Data ◽  
Daily Gain

Abstract Phenotyping a large number of crossbred progeny for the evaluation of purebred animals can be expensive. As genotyping with low-density panels is becoming cheaper, we aimed to evaluate the tradeoff between having different percentages of genotypes and phenotypes for crossbred progeny of candidate boars. We used the linear regression (LR) method to investigate changes in accuracy, bias, and inflation of breeding values for crossbred traits in purebred boars. A total of 304,582 purebred and 147,474 crossbred animals were phenotyped for average daily gain (ADG) and backfat thickness (BF), out of which 46,691 purebred and 13,117 crossbred animals were genotyped. Genomic information consisted of imputed genotypes for 40,247 SNP markers after quality control. A four-trait animal model under single-step GBLUP was used that included phenotypes recorded in purebred and crossbred animals as correlated traits. The LR statistics were calculated based on breeding values of young purebred sires from complete and partial data. The first complete data included genotypes for purebreds and phenotypes for purebreds and crossbreds, whereas the second included also genotypes for crossbreds. The partial data included phenotypes on 50% or none of the progeny of validation sires, with or without genotypes for crossbred animals. When 50% of the progeny has phenotypes, adding genotypes for crossbred progeny marginally increased accuracy of ADG (0.77 vs 0.78) for 47 boars with more than 150 progeny with phenotypes. No increase was observed for BF. A small increase in bias and inflation by adding crossbred genotypes was observed for ADG but not for BF. When no phenotypes were available for crossbred progeny, accuracy for both traits was lower but improved with crossbred genotypes for ADG (0.61 vs 0.64) for boars with more than 150 progeny. The tradeoff between phenotypes and genotypes should be further investigated in larger datasets with more validation boars.

CHARACTERISTICS OF PRODUCTIVE QUALITIES OF FAMILIES OF RED WHITE BELTED PIGS IN SE «RF ZORYANE» BREEDING FARM

2016 ◽  
Vol 52 ◽  
pp. 58-63
Author(s):  
L. V. Onishchenko ◽  
M. I. Danilchuk
Keyword(s):  
High Performance ◽  
Average Daily Gain ◽  
Live Weight ◽  
Litter Weight ◽  
Complex Evaluation ◽  
Appraisal Index ◽  
Daily Gain ◽  
Compactness Index

The most perspective genotype in our region is Red White-belted breed, which has high performance both under pure breeding and under crossing with other breeds. The results of complex evaluation of Red White-belted swine of the herd bred in SE "RF Zoryane" breeding farm are presented. It was revealed that animals of the farm comply with elite class and the first class. The main breeding boars used at the farm belong to such genealogical lines: Deviz, Division, Dantist, Debut, and Dobryak. In the structure of the herd, the most numerous was Dobryak line, which part was 58.8%, Division, Debut, Devis lines – 11.8% per line, Dantist line – 5.8%. The herd sows belong to 7 families: Drabowka, Dekada, Dyktsiya, Doina, Dylema, Delta, Dogma. Average prolificacy of the sows was 10.0 piglets. Litter weight at 60 days’ age was 181.0 kg, and live weight of piglet – 19.0 kg. The performance of sows as prolificacy increased by 0.6 head on average. The complex appraisal index for the herd was 104.1 points. The average daily gain of the replacement pigs was 570 g. The highest daily gain was from five to six months – 611.2 g, and the figure of compactness index characterized a certain elongation of animals, increasing meat traits. Further work with Red White-belted breed aims at preserving and expanding the breeding base and genealogical structure, as well as increasing the reproductive, fattening and meat traits.

Effect of supplementary Aspergillus niger phytase in diets for piglets on their performance and apparent digestibility of phosphorus

1992 ◽  
Vol 55 (3) ◽  
pp. 425-430 ◽  
Author(s):  
S. Beers ◽  
A. W. Jongbloed
Keyword(s):  
Aspergillus Niger ◽  
Average Daily Gain ◽  
Live Weight ◽  
Basal Diet ◽  
Apparent Digestibility ◽  
Feeding Trial ◽  
Daily Food ◽  
Microbial Phytase ◽  
Daily Gain ◽  
Aspergillus Niger Phytase

AbstractA total of 384 piglets from a three-way cross Yorkshire ♂ × (Finnish Landrace ♂ × Dutch Landrace♀) ♀ in the live-weight range of 11 to 25 kg were used in a feeding trial. The effect of supplementary microbial phytase from Aspergillus niger var. Van Tieghem on performance (average daily gain (ADG), average daily food intake (ADFI) and food conversion ratio (FCR)) and apparent digestibility of total phosphorus (P), in comparison with a non-supplemented basal diet or a diet supplemented with one or two levels of monocalcium phosphate (MCP), were studied.The piglets were allotted to 12 blocks. Within each block, four experimental diets were offered ad libitum for a period of 4 weeks i.e. (1) basal diet; (2) basal diet + 1·0 g P, from MCP per kg diet; (3) basal diet + 1·9 g P, from MCP per kg diet; and (4) basal diet + 1450 phytase units (PTU) per kg diet. The diets, with added chromium III oxide as a marker, were cold pelleted without steam at a temperature not above 60°C to avoid a possible inactivation of the phytase. In all diets the ratio calcium: digestible P was intended to be constant.Adding 1450 PTU of Aspergillus niger phytase enhanced the apparent digestibility of P by proportionately 0·216 when compared with diet 1 and by proportionately 0·100 compared with diet 3. In addition, significantly higher ADG and ADFI and better FCR were noted in pigs receiving supplementary microbial phytase than in pigs on any other treatment. The content of digestible P of the diet with added phytase, however, zvas between the two levels of the diets with added MCP.

Effects in bacon pigs of differing levels of nutrition to 20 kg. body weight

1964 ◽  
Vol 6 (3) ◽  
pp. 301-308 ◽  
Author(s):  
Henning E. Nielsen
Keyword(s):  
Body Weight ◽  
Average Daily Gain ◽  
Live Weight ◽  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Feed Conversion ◽  
Eye Muscle ◽  
Group 4 ◽  
Second Period ◽  
Daily Gain

Sixteen blocks of eight littermate pigs were weaned at 3 weeks of age and each divided into four groups. Various levels of nutrition were applied to the pigs so that the four groups reached 20 kg. at 59, 68, 80 and 91 days of age, respectively.Only small differences were observed between groups in feed conversion ratio to 20 kg.; however, Group 4 required more feed per kg. gain than the three other groups.During the second period (20–90 kg.) the pigs in each group were divided into two sub-groups, which were on a high and a low plane of nutrition respectively. In both sub-groups the type of feeding before 20 kg. influenced the average daily gain and feed conversion ratio. The older the pigs were at 20 kg. the higher the daily gain and the lower the feed conversion ratio in the following period. There was an increase in daily feed intake with increased age at 20 kg. for pigs fed ad lib. during the second period.An increase in age at 20 kg. caused a significant decrease in thickness of backfat, a greater area of eye muscle and a smaller area of fat overlying muscle. For pigs fed ad lib. the area of eye muscle was significantly increased by a higher age at 20 kg. live-weight.

Comprehensive evaluation of the productive and reproductive traits of sows of Yorkshire and Landrace breeds and their offspring

2021 ◽  
pp. 36-46
Author(s):  
A. A. Balnikov ◽  
Yu. S. Kazutova ◽  
N. M. Kostomakhin ◽  
I. F. Gridyushko ◽  
E. S. Gridyushko
Keyword(s):  
Comprehensive Evaluation ◽  
Average Daily Gain ◽  
Live Weight ◽  
Reproductive Traits ◽  
Young Pigs ◽  
The Republic ◽  
Daily Gain ◽  
Best Parameters

The purpose of the work was a comprehensive evaluation of the productive and reproductive traits of sows of Yorkshire and Landrace breeds and their offspring under the conditions of a breeding enterprise in the Republic of Belarus. During the studies of reproductive traits, it has been revealed that the highest rate of prolificacy among the evaluated breeds was distinguished by Yorkshire sows 14,0 heads for farrowing. In terms of milk content, Landrace sows were 2,5 kg or 4,57 % higher than Yorkshire sows. In terms of weight and socket weight per piglet at weaning at the age of 28 days sows Landrace piglets surpassed herdmates Yorkshire breed in the weight of the litter by 6,8 %, and the weight of one pig by 0,9 %. It has been found by the results of the evaluation of fattening and meat qualities of purebred young pigs that the best parameters were different gilts of Landrace breeds, whose age achieve the live weight of 100 kg was 163,1 days, and average daily gain of live weight – 864,8 g, which was higher than in young pigs of Yorkshire breed by 1,8 day or 1,09 %, and 28,9 g or by 3,46 %. The young pigs of Landrace breed has been characterized by the best values of the area of the “eye of loin” – 73,8 cm² and the highest yield and amount of meat – 68,5 % and 24 kg, which was 11,4 cm² or 18,2 % and 0,4 kg or 3,5 abs.%, respectively, higher than the herdmates of Yorkshire breed. The results obtained indicate the possibility of using boars and sows of Landrace and Yorkshire breeds not only in breeding, but also in industrial pig breeding.

ORGANIC ACIDS IN FEEDING OF PIGS AND THEIR EFFECT ON PRODUCTIVITY AND CLINICAL AND PHYSIOLOGICAL STATE

2018 ◽  
Vol 1 (2) ◽  
pp. 84-88
Author(s):  
L. A. Nikanova ◽  
Keyword(s):  
Organic Acids ◽  
Orthophosphoric Acid ◽  
Physiological State ◽  
Average Daily Gain ◽  
Initial Dosage ◽  
Live Weight ◽  
Feed Additive ◽  
Control Group ◽  
Daily Gain ◽  
Experimental Group

The influence of feed additive "Ormik" consisting of organic acids (formic acid, lactic acid, orthophosphoric acid, acetic acid), as a filler of diatomite crumb, introduced into concentrated fodders, on the biochemical parameters of blood serum of pigs and on productivity is considered in the article. The studied feed additive was added to the feed daily in the form of loose powder, mixing thoroughly. The initial dosage of the feed additive in the 1st week was 1 g/kg of feed, 2nd week and the following – 3 g/kg of feed. The average daily gain in the live weight of pigs in the experimental group was 11,0% higher than the control group. The animals of the experimental group were less sick and the safety of this group was 100%, in the control group it was 90%.

An analysis of the variation in the lean tissue distribution of sheep

1982 ◽  
Vol 34 (3) ◽  
pp. 257-264 ◽  
Author(s):  
B. T. Wolf
Keyword(s):  
Tissue Distribution ◽  
Genetic Correlation ◽  
Average Daily Gain ◽  
Genetic Correlations ◽  
Maximum Difference ◽  
Lean Tissue ◽  
Heritability Estimates ◽  
The Relationship ◽  
Daily Gain ◽  
Sire Breed

ABSTRACTThe distribution of lean tissue between eight standard joints was examined in 956 crossbred lambs slaughtered at constant live weights of either 35 or 40 kg. The sire breeds used were the Dorset Down, Ile-de-France, Oldenburg, Oxford, Suffolk and Texel. Sire breed did not have a significant effect on the proportion of total carcass lean found in the higher-priced joints but did show significant differences in the proportion of total carcass lean found in individual joints, with a maximum difference of 7·7 g total lean per kg joint being recorded. Similarly, small but significant effects due to ewe age (1 to 3 years), rearing type (single, twin, triplet), sex (male castrate, female) and weight of total lean were reported for the proportion of total carcass lean found in different joints.Heritability estimates ranged from 0·07 (s.e. 008) to 0·65 (s.e. 0·16) for the proportion of total lean in the best-end neck and higher-priced joints respectively. Phenotypic standard deviations of 5·8g/kg and 17·9g/kg were reported for the proportion of total lean found in the best-end neck and the higher-priced joints respectively. The genetic correlations between the proportion of total lean in each of the higher-priced joints and the proportion of total lean in the higher-priced joints combined were positive. A genetic correlation of 017 (s.e. 0·20) was found for the relationship between average daily gain from birth to slaughter and the proportion of total lean in the higher-priced joints.

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