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Simple Summary: In meat sheep and sheep bred for other purposes, meat quality is one of the factors evaluated in a breeding programme. In this study, we included 25 sheep breeds from Germany with a sufficient amount of performance and pedigree data. The heritability, genetic and residual correlations were estimated for daily weight gain, meatiness score and ultrasound measurements for the muscle and fat thickness of the sheep breeds. We employed animal models to analyse inbreeding depression by estimating linear slopes of inbreeding coefficients on meat performance traits. For daily weight gain, inbreeding depression was significant for all sheep breeds. When considering single breeds, significant inbreeding depression was only found in two breeds. The meatiness scores did not show significant inbreeding depression across breeds, nor in single breeds, but only in one breed. The ultrasound measurements for muscle and fat thickness were not significant for inbreeding depression either across or within breeds. Purging effects did not prove to be significant either across or within breeds. Our data show that inbreeding depression and purging can be present in traits under strong selection. This study provides estimates on genetic parameters, inbreeding depression and purging for meat performance measures from 25 German sheep breeds. All German meat, merino sheep breeds and breeds of other breeding directions with a sufficient number of pedigree and performance data were included in this study. Phenotypic traits retrieved from the national database OviCap were evaluated: daily weight gain, meatiness score and ultrasound measurements for muscle and fat thickness. We employed animal models to estimate heritability, variance and covariance components for these meat performance traits as well as inbreeding depression and purging. The heritabilities, on average, reached estimates of 0.55, 0.34, 0.53 and 0.61 for daily weight gain, meatiness score and ultrasound measurements for muscle and fat thickness, respectively. We estimated the linear regression slopes for the individual rate of inbreeding, new and ancestral inbreeding, as well as the inbreeding coefficient and its interaction with the inbreeding coefficient of Ballou, employing animal models with non-genetic effects and the additive genetic effect of the animal. Across all breeds, inbreeding was only significant for daily weight gain, whereas for all other traits, estimates were not significant. Within sheep breeds, we found significant inbreeding depression for daily weight gain in German Mutton Merino and German Blackheaded Mutton as well as for the meatiness score in German Whiteheaded Mutton. Significant effects for purging, based on ancestral inbreeding and the interaction effect of the classical inbreeding coefficient with the inbreeding coefficient of Ballou, were not obvious either across or within any sheep breed. A 1% increase in inbreeding significantly decreased the phenotypic trait median of daily weight gain across all sheep breeds by 0.50% and 0.70% of phenotypic and genetic standard deviation, respectively. Purging effects due to ancestral inbreeding were not significant in any breed or across breeds. The results of this study may indicate that inbreeding depression may be more harmful in traits under stronger selection than in traits that exert low selection pressure. The results of this study demonstrate the different effects that result in meat performance traits due to inbreeding. With increasing rates of inbreeding and critical effective population sizes, selection intensity for breeding objectives has to be critically reviewed for each sheep breed. Inbreeding depression and purging should be evaluated in order to prevent a decrease in trait means due to inbreeding and to determine whether detrimental alleles are eliminated. [ABSTRACT FROM AUTHOR]

In this study, the effect of different measurements of ancestral inbreeding on birthweight, calving ease and stillbirth were analysed. Three models were used to estimate the effect of ancestral inbreeding, and the estimated regression coefficient of phenotypic data on different measurements of ancestral inbreeding was used to quantify the effect of ancestral inbreeding. The first model included only one measurement of inbreeding, whereas the second model included the classical inbreeding coefficients and one alternative inbreeding coefficient. The third model included the classical inbreeding coefficients, the interaction between classical inbreeding and ancestral inbreeding, and the classical inbreeding coefficients of the dam. Phenotypic data for this study were collected from February 1998 to December 2008 on three large commercial milk farms. During this time, 36 477 calving events were recorded. All calves were weighed after birth, and 8.08% of the calves died within 48 h after calving. Calving ease was recorded on a scale between 1 and 4 (1 = easy birth, 4 = surgery), and 69.95, 20.91, 8.92 and 0.21% of the calvings were scored with 1, 2, 3 and 4, respectively. The average inbreeding coefficient of inbred animals was 0.03, and average ancestral inbreeding coefficients were 0.08 and 0.01, depending on how ancestral inbreeding was calculated. Approximately 26% of classically non-inbred animals showed ancestral inbreeding. Correlations between different inbreeding coefficients ranged between 0.46 and 0.99. No significant effect of ancestral inbreeding was found for calving ease, because the number of animals with reasonable high level of ancestral inbreeding was too low. Significant effects of ancestral inbreeding were estimated for birthweight and stillbirth. Unfavourable effects of ancestral inbreeding were observed for birthweight. However, favourable purging effects were estimated for stillbirth, indicating that purging could be partly beneficial for genetic improvement of stillbirth. [ABSTRACT FROM AUTHOR]

This study is part of the larger Christina Barz Study, and it compared consecutively admitted patients with purging disorder (PurD; N = 225) with consecutively admitted patients with anorexia nervosa binge eating/purging subtype (AN-bp; N = 503) and bulimia nervosa purging subtype (BN-p; N = 756). Participants answered self-rating questionnaires on admission, at the end of inpatient treatment, and in a 5-year follow-up. Patients with PurD reported lower severity of general psychopathology than patients with AN-bp and lower severity of eating disorder symptoms than patients with AN-bp and BN-p on admission. Eating disorder symptoms of patients with PurD improved less during the course than of the comparison groups. Diagnostic perseverance was stronger in the PurD group than for patients with AN-bp; mortality was higher than for patients with BN-p. Predictors for better outcome differed for the groups. Our results provide new data about the long-term course of patients with PurD and indicate clinical relevance of the disorder. Copyright © 2013 John Wiley & Sons, Ltd and Eating Disorders Association. [ABSTRACT FROM AUTHOR]