Heritability estimates and effect on lifetime reproductive performance of age at puberty in sows

2018 ◽  
Vol 195 ◽  
pp. 207-215 ◽  
Author(s):  
Qingqing Li ◽  
Xiaolong Yuan ◽  
Zitao Chen ◽  
Ailing Zhang ◽  
Zhe Zhang ◽  
...  
1993 ◽  
Vol 73 (2) ◽  
pp. 287-293
Author(s):  
S. L. Boyles ◽  
L. J. Johnson ◽  
W. D. Slanger ◽  
B. J. Kreft ◽  
J. D. Kirsch

Twenty-six of 52 heifers with an average liveweight of 318 kg were dewormed by intraruminal injection of oxfendazole and placed in drylot on 31 January. The other 26 animals served as controls. All heifers were pastured starting on 14 June and the treatment heifers were dewormed in the same manner as at the start of the experiment (31 January) on 1 July and 31 July. The groups started out with similar total worm eggs per gram of fecal sample, but the dewormed heifers had fewer counts each month thereafter. The drylot average daily gain of the treated heifers was higher (P = 0.01) and less variable (P = 0.12) and by 29 May these animals were heavier by 11.7 kg (P = 0.10). The treated animals did not gain as fast on pasture (P = 0.20), but the gain continued to be less variable (P = 0.09). Age at puberty was not different. Number of open heifers in the treated group was 4 vs. 15% for the control group (P = 0.18). Deworming by intraruminal injection resulted in faster feedlot gains, more uniform gains during both drylot and pasture, reduced parasites and no abscess at injection sites. Key words: Anthelmintics, oxfendazole, cattle, heifers


1981 ◽  
Vol 96 (1) ◽  
pp. 107-113 ◽  
Author(s):  
T. G. Martin ◽  
D. Nicholson ◽  
C. Smith ◽  
D. I. Sales

SUMMARYData on 902 ewes (1755 records) bom over 7 years in the synthetic ABRO Dam Line were analysed by least squares. Reproductive traits of the ewe were not affected by whether she was a single or a twin or by the age of her dam. Ewe age had major effects on all reproductive traits. Litter weight traits were affected by the sex distribution and the age of the litter when weighed.Heritability estimates, both by half sib and regression methods, were low for litter size, low to moderate for litter weights, and higher for ewe and fleece weights. Genetic correlations among the litter-weight traits were high. Together with the heritability estimates, they indicated that selection on litter weight at birth (and perhaps other traits) might give a greater change in total litter weight at weaning, the main measure of ewe productivity and the objective in improvement, than would direct selection.


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.


2014 ◽  
Vol 12 (2) ◽  
pp. 211-215
Author(s):  
MA Motaleb ◽  
MK Chowdhury ◽  
MA Islam ◽  
JU Ahmed ◽  
MMU Bhuiyan

Reproductive performance is considered as one of the important factors affecting the productivity and economy of the pig farms. The objective of the study was to determine the reproductive parameters of gilts and sows by direct interview method using a pretested questionnaire in selected area of Bangladesh. A total of 20 pig farms having 60 gilts and 27 sows were included in this investigation. The present study revealed that, in native female pigs, the age at puberty was 229.0 ± 16.7 days, the oestrous cycle length was 22.2 ± 1.2 days, the oestrous duration was 37.9 ± 14.2 hours, the gestation length was 113.5 ± 1.0 days, the interval between farrowing and onset of oestrus was 62.9 ± 11.9 days and the number of piglets born per native sow was 5.25 ± 2.3. It was also found that the first service pregnancy rate was 71.7% and the number of services required for each pregnancy was 1.3. The highest proportion of pigs was detected in oestrus by observing stand to be mounted by boars. It is concluded that reproductive parameters of native sows need to be improved for better production.DOI: http://dx.doi.org/10.3329/bjvm.v12i2.21294 Bangl. J. Vet. Med. (2014). 12 (2): 211-215  


1977 ◽  
Vol 88 (2) ◽  
pp. 443-447 ◽  
Author(s):  
A. M. Aboul-Naga ◽  
E. A. Afifi

SUMMARYWool production from different flocks of Ossimi, Rahmani and Barki Egyptian local sheep, raised at six different locations in the country was studied. Different genetic parameters for greasy fleece weight of the three breeds were estimated.Location was of significant effect on annual greasy fleece weight of Rahmani sheep only. With the adjustment for differences in yield percentages, differences in clean wool production from one location to another were slight for the three breeds. Age of ewe was of highly significant effect on annual greasy fleece weight.Heritability estimates of annual greasy fleece weight of the ewes were found to be generally low in the three breeds (range 0·00–0·34). The estimates differed markedly with age; those of the yearling fleece weight of Rahmani and Barki ewes were the highest, being 0–19 and 0–34, respectively.Repeatability estimates of annual greasy fleece weight were also low, being 0·11–0·04 and 0·29 for Ossimi, Rahmani and Barki ewes, respectively.Estimates of genetic correlation between yearling greasy fleece weight of the Ossimi and Rahmani ewes and their weaning and yearling body weights were high and positive. Those between annual greasy fleece weight of the ewes and their reproductive performance traits differed greatly in the two breeds.


2018 ◽  
Vol 47 (1) ◽  
pp. 1-12 ◽  
Author(s):  
MAMY Khandoker ◽  
N Afini ◽  
A Azwan

An experiment was conducted at AZ-Zahra Farm, Sandakan, Sabah, Malaysia to investigate the productive and reproductive performance of Saanen dairy goat. Body weight at different ages were collected once while birth weight was collected when does gave birth. On the other hand, milk production of each individual per day was received continuously for three months. The data on reproductive parameters such as length of estrus cycle, duration of estrus period, age at puberty, gestation length, age at first kidding, litter size, birth weight and kid mortality were noted. Descriptive statistics such as number, percentage, mean, standard deviation were performed. T-test was also conducted to know the statistical difference between the groups. Result demonstrated that body weight increases significantly (p<0.01) with the advancement of the age. The highest daily milk yield was found in 2-3 years of age. Dam with multiple kids produced more milk than dam with single kid. Estrus cycle of Saanen goats was found 21 days, the average estrus period duration was 2.75 days, age at puberty was 8.33 months, first kidding age was 14.2 months and gestation period was 150 days on an average. With the increase of the age of dam litter size increased. Meanwhile average birth weight increased as age of dam increased from 2.85 kg in 1 year to 3.26 kg in 3 years. Male kids born heavier than females (3.23±0.62 vs. 2.75±0.58 kg) and single kids were heavier than twin kids (3.07±0.66 kgvs2.70±0.28 kg). Low mortality rate of kids was recorded in this study (6.4%). It can be concluded that the overall productive and reproductive performances of Saanen goat at AZ-Zahra farm were within the acceptable level and the variation recorded in different parameters is very much usual. Bang. J. Anim. Sci. 2018. 47 (1): 1-12


1995 ◽  
Vol 61 (1) ◽  
pp. 115-121 ◽  
Author(s):  
R. B. Holder ◽  
W. R. Lamberson ◽  
R. O. Bates ◽  
T. J. Safranski

AbstractA study was conducted to evaluate the effect of decreasing age of puberty on lifetime productivity in sows. Two lines of gilts from the Nebraska Gene Pool population were used in this study: a line that had been selected for decreased age at puberty (AP) and a line in which selection had been random (RS). The study was conducted in two parts. In part one, 75 gilts were mated at second oestrus and the productivity measured over five parities. A second experiment utilizing 68 gilts was conducted to provide further data for comparing litter size at parity 1, and also to compare ovulation rates in the two lines at second oestrus. Results showed that litter size was similar in both lines across parities. After five parities the percentage of sows farrowing relative to parity 1 was 58-8% for the AP line but only 39·4% for the RS line (P = 0·17). Litter birth weight, litter size and weight at 21 days, number weaned, and lactation food consumption were similar for both lines. Lactation weight loss was not significantly different between the two lines (60·9 (s.e. 5·9) v. 527 (s.e. 5·0) kg, for RS and AP gilts, respectively) but was consistent with the slightly longer weaning to remating intervals in the RS line (7·8 (s.e. 0·7) v. 6·6 (s.e. 0·7) days, P = 0·22). Ovulation rate at second oestrus did not differ between the two lines (14·1 (s.e. 0·9) v. 14·3 (s.e. 0·5), for RS and AP gilts, respectively). The regression of mean accumulative productivity on time was in favour of the AP line (P = 0·05). These results suggest that reproductive performance is not impaired in gilts which have been selected to reach puberty at earlier ages, and productivity at a specific age may be enhanced.


2014 ◽  
Vol 54 (1) ◽  
pp. 74 ◽  
Author(s):  
D. J. Johnston ◽  
N. J. Corbet ◽  
S. A. Barwick ◽  
M. L. Wolcott ◽  
R. G. Holroyd

Genetic correlations of young bull and heifer puberty traits with measures of early and lifetime female reproductive performance were estimated in two tropical beef cattle genotypes. Heifer age at puberty was highly (rg = –0.71 ± 0.11) and moderately (rg = –0.40 ± 0.20) genetically correlated with pregnancy rate at first annual mating (mating 1) and lifetime annual calving rate, respectively in Brahman (BRAH). In Tropical Composite (TCOMP), heifer age at puberty was highly correlated with reproductive outcomes from the first re-breed (mating 2), mainly due to its association with lactation anoestrous interval (rg = 0.72 ± 0.17). Scrotal circumference were correlated with heifer age at puberty (rg = –0.41 ± 0.11 at 12 months in BRAH; –0.30 ± 0.13 at 6 months in TCOMP) but correlations were lower with later female reproduction traits. Bull insulin-like growth factor-I was correlated with heifer age at puberty (rg = –0.56 ± 0.11 in BRAH; –0.43 ± 0.11 in TCOMP) and blood luteinising hormone concentration was moderately correlated with lactation anoestrous interval (rg = 0.59 ± 0.23) in TCOMP. Semen quality traits, including mass activity, motility and percent normal sperm were genetically correlated with lactation anoestrus and female lifetime female reproductive traits in both genotypes, but the magnitudes of the relationships differed with bull age at measurement. Preputial eversion and sheath scores were genetically associated with lifetime calving and weaning rates in both genotypes. Several of the early-in-life male and female measures examined were moderately to highly genetically correlated with early and lifetime female reproduction traits and may be useful as indirect selection criteria for improving female reproduction in tropical breeds in northern Australia.


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