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J Philipsson - One of the best experts on this subject based on the ideXlab platform.
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genetic relationships between Calving and carcass traits for charolais and hereford cattle in sweden
Journal of Animal Science, 2004Co-Authors: S Eriksson, A Nasholm, K Johansson, J PhilipssonAbstract:: The objective of this study was to estimate genetic correlations between Calving difficulty score and carcass traits in Charolais and Hereford cattle, treating first and later parity Calvings as different traits. Genetic correlations between birth weight and carcass traits were also estimated. Field data on 59,182 Charolais and 27,051 Hereford Calvings, and carcass traits of 5,260 Charolais and 1,232 Hereford bulls, were used in bivariate linear animal model analyses. Estimated heritabilities were moderate to high (0.22 to 0.50) for direct effects on birth weight, carcass weight, and (S)EUROP (European Community scale for carcass classification) grades for carcass fleshiness and fatness. Heritabilities of 0.07 to 0.18 were estimated for maternal effect on birth weight, and for direct and maternal effects on Calving difficulty score at first parity. Lower heritabilities (0.01 to 0.05) were estimated for Calving difficulty score at later parities. Carcass weight was positively genetically correlated (0.11 to 0.53) with both direct and maternal effects on birth weight and with direct effects on Calving difficulty score. Carcass weight was, however, weakly or negatively (-0.70 to 0.07) correlated with maternal Calving difficulty score. Higher carcass fatness grade was genetically associated with lower birth weight, and in most cases, also with less difficult Calving. Genetic correlations with carcass fleshiness grade were highly variable. Moderately unfavorable correlations between carcass fleshiness grade and maternal Calving difficulty score at first parity were estimated for both Charolais (0.42) and Hereford (0.54). This study found certain antagonistic genetic relationships between Calving performance and carcass traits for both Charolais and Hereford cattle. Both direct and maternal Calving performance, as well as carcass traits, should be included in the breeding goal and selected for in beef breeds.
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genetic parameters for Calving difficulty stillbirth and birth weight for hereford and charolais at first and later parities
Journal of Animal Science, 2004Co-Authors: S Eriksson, A Nasholm, K Johansson, J PhilipssonAbstract:: The aim of this study was to estimate direct and maternal genetic parameters for Calving difficulty score, stillbirth, and birth weight at first and later parities for Charolais and Hereford cattle in Sweden. Calving traits have long been recorded for pure-bred beef cattle in Sweden, but only birth weight has been used in the selection in order to avoid Calving difficulties. Linear animal model analyses included records on birth weight for 60,309 Charolais and 30,789 Hereford calves born from 1980 to 1999, and Calving traits for 74,538 Charolais and 37,077 Hereford calves born from 1980 to 2001. The frequencies of difficult Calvings and stillbirths were approximately 6% at first and 1 to 2% at later parities for both breeds. Fewer than half the stillborn calves were born from difficult Calvings. Heritabilities estimated for birth weight in different univariate and bivariate analyses for Charolais and Hereford calves born at first and later parities ranged from 0.44 to 0.51 for direct effects and 0.06 to 0.15 for maternal effects. Heritabilities on the observable scale for Calving difficulty score of Charolais and Hereford, scored in three classes, ranged from 0.11 to 0.16 for direct and 0.07 to 0.12 for maternal effects at first parity, and lower at later parities. All estimated heritabilities for stillbirth were very low (0.002 to 0.016 on the observable scale). Direct-maternal genetic correlations were negative, with few exceptions. Genetic correlations between the traits and between parities within traits were generally moderate to high and positive. Calving difficulty score should be included in the genetic evaluation of beef breeds in Sweden, whereas progeny groups in Swedish beef populations are too small for stillbirth to be considered directly.
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genetic effects on stillbirth and Calving difficulty in swedish holsteins at first and second Calving
Journal of Dairy Science, 2003Co-Authors: L Steinbock, A Nasholm, K Johansson, B Berglund, J PhilipssonAbstract:Abstract In Swedish Holstein dairy cattle, genetic effects on stillbirth and Calving difficulty were studied in 411,409 first- and 281,193 second-calvers. A linear single-trait sire-maternal grandsire model and a threshold model using a Gibbs sampling technique were used to analyse Calving data from 1985 to 1996. In first Calving when using the linear model, the heritability of stillbirth on the visible scale was 4% for the direct effect and 3% for the maternal effect. For Calving difficulty it was 6% and 5% for direct and maternal effects, respectively. In second Calving the corresponding heritabilities for the two traits were considerably lower, less than 1%. Adjusting for Calving difficulty in linear analysis of stillbirth halved the heritabilities for the direct and maternal effects in first Calving. When using a threshold model, heritabilities for stillbirth in first-calvers were 12% and 8% for direct and maternal effects, respectively, and for Calving difficulty they were 17% and 12%. At second Calving corresponding heritabilities were 2 to 4% for stillbirth and 4 to 7% for Calving difficulty. The correlation between direct and maternal effects was around −0.1, irrespective of whether the linear or the threshold model was used for first-calvers. The genetic correlations between bulls' EBV from first and second Calving were 0.4 to 0.5 for direct and maternal effects in stillbirth, whereas they were 0.6 to 0.7 for Calving difficulty. In first-calvers there was a substantial genetic variation in both traits, expressed by differences between breeding values of bulls, despite fairly low heritability. The results obtained in this study suggest that first-parity records should preferably be used for genetic evaluation of bulls for Calving performance. In such routine evaluations both stillbirth and Calving difficulty, and both direct and maternal effects, should be included.
Ann Van Soom - One of the best experts on this subject based on the ideXlab platform.
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Reproductive performance parameters in a large population of game-ranched white rhinoceroses (Ceratotherium simum simum).
PloS one, 2017Co-Authors: Cyrillus Ververs, Martine Van Zijll Langhout, Miel Hostens, Michelle Otto, Jan Govaere, Barbara S. Durrant, Ann Van SoomAbstract:The population of free-roaming white rhinoceroses (Ceratotherium simum) is under serious threat. Captive breeding of this species is therefore becoming more important, but this is challenging and often not successful. Obtaining reproductive reference values is a crucial aspect of improving these breeding results. In this study performed between 2008 and 2016, reproductive performance was analysed in 1,354 animals kept in a 8000 hectares game-ranched environment. Descriptive statistics of this captive population showed an average annual herd growth (%) of 7 .0±0.1 (min -9 -max 15). Average Calving rates were calculated as an annual Calving rate of 20% and biennial Calving rate of 37% adult females Calving per year. Females had a median age of 83.2 months at first Calving (IQR 72.9-110.7) and inter-Calving intervals of 29.2 (IQR 24.6-34.8) months. Furthermore, translocations of animals did not interfere with reproductive success in terms of inter-Calving periods or age at first Calving. Multivariate models showed a clear seasonal Calving pattern with a significant increase of the number of Calvings during December-April when compared to April-December. Our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves.
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109 reproductive performance parameters in a large herd of confined free roaming white rhinoceroses ceratotherium simum
Reproduction Fertility and Development, 2017Co-Authors: Cyrillus Ververs, Martine Van Zijll Langhout, Miel Hostens, Michelle Otto, Jan Govaere, Ann Van SoomAbstract:During the last decade, the population of wild white rhinoceroses has been in steady decline, mainly because of increased poaching incidents and habitat loss. Therefore, more data are necessary on reproduction of this endangered species in order to improve captive breeding, which is at present not very successful. Currently, ~20,000 Southern white rhinoceroses are remaining of which the majority are privately owned. The aim of this study was to create reference values of several reproductive parameters for future white rhinoceros breeding. In previous studies, only low numbers of animals have been observed, often in captive settings. In this study performed between 2008 and 2016, reproductive performance was analysed in 1300 animals kept in a geographically identical, confined free-roaming environment. Analyses were performed in R (R Development Core Team, 2008) using the lme4 and fixed package to model the number of animals born (family = Poisson) and sex ratio (family = binomial). Females had a median age of 83.2 months at first Calving (interquartile range: 72.9–110.7) and interCalving intervals of 29.2 (interquartile range: 24.6–34.8) months. Fertility records were excellent with 38% adult females Calving per year when compared to previous research, in which first reproduction occurred between 78 and 138 months of age with an interCalving period of 3 years average. A clear seasonal Calving pattern was seen with a significant increase of Calvings during December–April when compared to April–December. In contrast to the Trivers-Willard hypothesis, our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves. Furthermore, translocations of animals did not seem to interfere with reproductive success when looking at interCalving periods or age at first Calving. In the free roaming environment of over 10,000 ha, this captive population showed an average annual population growth (%) of 18 ± 0.07 (minimum 5 to maximum 26). As such, comparable breeding management systems can increase population numbers and contribute to increase dwindling population numbers of the wild white rhinoceros. This is the first study to describe reproductive performances in the white rhinoceros at such large scale, indicating that confined free-roaming populations can be used for captive breeding of white rhinoceros to contribute to white rhinoceros conservation.
D P Berry - One of the best experts on this subject based on the ideXlab platform.
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genetics of reproductive performance in seasonal Calving dairy cattle production systems
2013Co-Authors: D P Berry, J F Kearney, K Twomey, R D EvansAbstract:Profitable seasonal Calving dairy production systems require a cow that will establish pregnancy early in the breeding season implying a quick return to service post-Calving and good pregnancy rates. Genetic selection provides an opportunity to achieve this goal so therefore the objective of this study was to estimate the necessary genetic parameters for fertility traits, pertinent to seasonal Calving herds, in order to facilitate genetic selection for fertility. The data, following editing, consisted of parity 1 to 3 records on up to 397,373 Holstein-Friesian dairy cows in Ireland. Variance components for the defined interval fertility traits (age at first Calving, Calving to first service interval, Calving interval), binary fertility traits (submission rate in the first 21 days of the breeding season, pregnant to first service, pregnant in the first 42 days of the breeding season, calved in the first 42 days of the Calving season) and the count fertility trait (number of services) were estimated using univariate animal models and covariances among traits were estimated using bivariate sire models. Heritability estimates of the nine fertility traits (including age at first Calving and survival) varied from 0.01 to 0.07 within parity one to three. The coefficient of genetic variation for the fertility traits varied from 3.3% to 15.3%. Calving to first service interval, within parity, was moderately positively genetically correlated (0.54 to 0.75) with Calving interval and was, in general, moderately negatively correlated with both submission rate (-0.68 to -0.29) and pregnant in the first 42 days of the breeding season (-0.36 to -0.14). Calving interval was moderately positively correlated (0.24 to 0.68) with number of services. Irrespective
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risk factors for Calving assistance and dystocia in pasture based holstein friesian heifers and cows in ireland
Veterinary Journal, 2011Co-Authors: John F Mee, D P Berry, A R CromieAbstract:The incidence of and risk factors associated with Calving assistance and dystocia in pasture-based dairy herds were determined from analysis of 152,641 records of full-term Calvings from Holstein–Friesian dams served by artificial insemination (AI) sires of seven breeds in herds of 20 Calvings or more per year over 4 years. The overall incidence of Calving assistance and dystocia was 31.1% and 6.8%, respectively. The incidence in primiparae and pluriparae was 40.0% and 28.2% for assistance, and 9.3% and 5.8% for dystocia, respectively. Association analyses were undertaken using generalised estimating equations using a logit link function. The likelihood of Calving assistance or dystocia did not change over time but was greatest in autumn and in spring. The likelihood of Calving assistance or dystocia was greater for males in primiparae and males sired by Charolais sires. The odds of Calving assistance and dystocia were greater in twin calves (OR 2.0 and 2.4; P < 0.001) and in dams that had dystocia at the previous Calving (OR 1.65 and 2.9; P < 0.001). The logit of the probability of Calving assistance and dystocia increased linearly per unit increase in sire predicted transmitting ability for direct Calving difficulty. The probability of assisted Calving, but not dystocia, increased linearly in primiparae as animals calved at a younger age relative to the median age at first Calving. Herd size and day of the week of Calving were not associated with the odds of dystocia. Stakeholders must focus on identified modifiable risk factors to control the incidence of dystocia in dairy herds.
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Periparturient Climatic, Animal, and Management Factors Influencing the Incidence of Milk Fever in Grazing Systems
Journal of Dairy Science, 2006Co-Authors: J. R. Roche, D P BerryAbstract:The objective of the present study was to quantify the climatic, animal, and management factors influencing incidence of milk fever (MF) in cows exposed to grazing systems. Data were extracted on 4,469 Calvings of multiparous cows in a seasonal Calving research herd between 1970 and 2000. Climatic data during the Calving period also were extracted for these years. Poisson regression was used to investigate the effect of climate on frequency of MF within year; the offset variable was the number of cows at risk for MF at that time. Generalized estimating equations, with cow included as a repeated effect, were used to quantify the effect of parturition-associated cow and management factors on the logit of the probability of MF. Both univariate and multivariate analyses were performed. Explanatory variables investigated included time of Calving relative to the herd-year Calving period, parity, body weight, breed of cow, body condition score at Calving, weight and gender of the calf, incidence of twin calves, Calving inductions, and Calving assistance. Odds of recurring MF within cow, as well as the timing of MF relative to day of Calving, was quantified using generalized estimating equations with cow included as a repeated effect. Results show significant effects of evaporation, minimum grass temperature, difference between ambient maximum and minimum temperature, and rainfall on the odds of MF occurring, with a greater incidence at greater evaporation, larger diurnal variation in air temperature, greater rainfall, and lesser grass minimum temperature. Cow factors, such as age, excessive or poor body condition score, and requirement for Calving assistance increased the odds of MF; a lesser odds ratio was observed in cows hormonally induced to calve and those that had twin births. Results indicate that herd managers may identify the day of greatest risk for MF and cows that are at greatest risk of MF based on climatic, cow, and management factors.
Cyrillus Ververs - One of the best experts on this subject based on the ideXlab platform.
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Reproductive performance parameters in a large population of game-ranched white rhinoceroses (Ceratotherium simum simum).
PloS one, 2017Co-Authors: Cyrillus Ververs, Martine Van Zijll Langhout, Miel Hostens, Michelle Otto, Jan Govaere, Barbara S. Durrant, Ann Van SoomAbstract:The population of free-roaming white rhinoceroses (Ceratotherium simum) is under serious threat. Captive breeding of this species is therefore becoming more important, but this is challenging and often not successful. Obtaining reproductive reference values is a crucial aspect of improving these breeding results. In this study performed between 2008 and 2016, reproductive performance was analysed in 1,354 animals kept in a 8000 hectares game-ranched environment. Descriptive statistics of this captive population showed an average annual herd growth (%) of 7 .0±0.1 (min -9 -max 15). Average Calving rates were calculated as an annual Calving rate of 20% and biennial Calving rate of 37% adult females Calving per year. Females had a median age of 83.2 months at first Calving (IQR 72.9-110.7) and inter-Calving intervals of 29.2 (IQR 24.6-34.8) months. Furthermore, translocations of animals did not interfere with reproductive success in terms of inter-Calving periods or age at first Calving. Multivariate models showed a clear seasonal Calving pattern with a significant increase of the number of Calvings during December-April when compared to April-December. Our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves.
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109 reproductive performance parameters in a large herd of confined free roaming white rhinoceroses ceratotherium simum
Reproduction Fertility and Development, 2017Co-Authors: Cyrillus Ververs, Martine Van Zijll Langhout, Miel Hostens, Michelle Otto, Jan Govaere, Ann Van SoomAbstract:During the last decade, the population of wild white rhinoceroses has been in steady decline, mainly because of increased poaching incidents and habitat loss. Therefore, more data are necessary on reproduction of this endangered species in order to improve captive breeding, which is at present not very successful. Currently, ~20,000 Southern white rhinoceroses are remaining of which the majority are privately owned. The aim of this study was to create reference values of several reproductive parameters for future white rhinoceros breeding. In previous studies, only low numbers of animals have been observed, often in captive settings. In this study performed between 2008 and 2016, reproductive performance was analysed in 1300 animals kept in a geographically identical, confined free-roaming environment. Analyses were performed in R (R Development Core Team, 2008) using the lme4 and fixed package to model the number of animals born (family = Poisson) and sex ratio (family = binomial). Females had a median age of 83.2 months at first Calving (interquartile range: 72.9–110.7) and interCalving intervals of 29.2 (interquartile range: 24.6–34.8) months. Fertility records were excellent with 38% adult females Calving per year when compared to previous research, in which first reproduction occurred between 78 and 138 months of age with an interCalving period of 3 years average. A clear seasonal Calving pattern was seen with a significant increase of Calvings during December–April when compared to April–December. In contrast to the Trivers-Willard hypothesis, our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves. Furthermore, translocations of animals did not seem to interfere with reproductive success when looking at interCalving periods or age at first Calving. In the free roaming environment of over 10,000 ha, this captive population showed an average annual population growth (%) of 18 ± 0.07 (minimum 5 to maximum 26). As such, comparable breeding management systems can increase population numbers and contribute to increase dwindling population numbers of the wild white rhinoceros. This is the first study to describe reproductive performances in the white rhinoceros at such large scale, indicating that confined free-roaming populations can be used for captive breeding of white rhinoceros to contribute to white rhinoceros conservation.
S Brotherstone - One of the best experts on this subject based on the ideXlab platform.
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the genetic relationship between Calving interval body condition score and linear type and management traits in registered holsteins
Journal of Dairy Science, 2000Co-Authors: J E Pryce, M P Coffey, S BrotherstoneAbstract:The trend to poorer fertility in dairy cattle with rising genetic merit for production over the last decade suggests that breeding goals need to be broadened to include fertility. This requires reliable estimates of genetic (co)variances for fertility and other traits of economic importance. In the United Kingdom at present, reliable information on Calving dates and hence Calving intervals are available for most dairy cows. Data in this study consisted of 44,672 records from first lactation heifers on condition score, linear type score, and management traits in addition to 19,042 Calving interval records. Animal model REML was used to estimate (co)variance components. Genetic correlations of body condition score (BCS) and angularity with Calving interval were -0.40 and 0.47, respectively, thus cows that are thinner and more angular have longer Calving intervals. Genetic correlations between Calving interval and milk, fat, and protein yields were between 0.56 and 0.61. Records of phenotypic Calving interval were regressed on sire breeding values for BCS estimated from records taken at different months of lactation and breeding values for BCS change. Genetic correlations inferred from these regressions showed that BCS recorded 1 mo after Calving had the largest genetic correlation with Calving interval in first lactation cows. It may be possible to combine information on Calving interval, BCS, and angularity into an index to predict genetic merit for fertility.
