Exploring the use of residual variance for uniformity of body weight in meat quail lines using Bayesian inference.

1. Uniformity in animal products is an important aspect of the production system. Several studies have reported estimates of genetics on residual variance in different species, indicating that it could be exploited to improve uniformity by selection. Nevertheless, there are no reports about the possibilities of such a selection strategy in meat quail.2. Records of hatching weight (HW) and body weight at 42 days (W42) of female and male birds from two meat quail lines (UFV1 and UFV2) were analysed. A three-step genetic evaluation was used to investigate the effect of genetic variation on residual variance of HW and W42 in both lines. In Step 1, a single-trait model was fitted to the data. In Step 2, log-transformed squared estimated residuals (ln(ê2)) were evaluated for these traits. In Step 3, a multi-trait analysis was performed to estimate the genetic correlation between the additive genetic effects for HW, W42, and their respective ln(ê2).3. The heritability estimates ranged from 0.12 to 0.23 for HW and from 0.22 to 0.35 for W42. The estimated heritabilities for the residual part were low and ranged from 0.0003 to 0.02 for both traits, and the genetic coefficient of variation residual variance estimates ranged from 0.31 to 0.42 for HW and from 0.09 to 0.25 for W42. Genetic correlations between the means (HW and W42) and ln(ê2) values were both positive and did not differ from zero, indicating no association between mean and ln(ê2).4. In conclusion, the uniformity of HW and W42 could be improved by selecting for lower residual variance in both meat quail lines, but the accuracy of selection may be low due to low heritability for uniformity, mainly for W42.

Collagen type IV-related nephropathies in Portugal: pathogenic COL4A3 and COL4A4 mutations and clinical characterization of 25 families.

Pathogenic mutations in genes COL4A3/COL4A4 are responsible for autosomal Alport syndrome (AS) and thin basement membrane nephropathy (TBMN). We used Sanger sequencing to analyze all exons and splice site regions of COL4A3/COL4A4, in 40 unrelated Portuguese probands with clinical suspicion of AS/TBMN. To assess genotype-phenotype correlations, we compared clinically relevant phenotypes/outcomes between homozygous/compound heterozygous and apparently heterozygous patients. Seventeen novel and four reportedly pathogenic COL4A3/COL4A4 mutations were identified in 62.5% (25/40) of the probands. Regardless of the mutated gene, all patients with ARAS manifested chronic renal failure (CRF) and hearing loss, whereas a minority of the apparently heterozygous patients had CRF or extrarenal symptoms. CRF was diagnosed at a significantly younger age in patients with ARAS. In our families, the occurrence of COL4A3/COL4A4 mutations was higher, while the prevalence of XLAS was lower than expected. Overall, a pathogenic COL4A3/COL4A4/COL4A5 mutation was identified in >50% of patients with fewer than three of the standard diagnostic criteria of AS. With such a population background, simultaneous next-generation sequencing of all three genes may be recommended as the most expedite approach to diagnose collagen IV-related glomerular basement membrane nephropathies.

Coleta e avaliaçäo de sêmen canino / Semen collection and evalution in dogs

Foram estudados 171 ejaculados de 21 reprodutores caninos das raças Dobermann, Whippet, Beagle, Afghan Hound, Fila Brasileiro, Pastor Alemäo e Rotweiller com idades entre 12 e 84 meses. O sêmen foi coletado obedecendo-se a existência de fraçöes distintas do ejaculado normal e analisado quanto ao tempo de ejaculaçäo, volume e concentraçäo. A primeira fraçäo foi perdida durante a manipulaçäo dos animais; a segunda fraçäo apresentou os valores de 3,00 mais ou menos 0,20 min, 2,40 mais ou menos 1,80 ml e 258,00 mais ou menos 10,20 x 10 elevado à sexta potência sptz/ml; a terceira fraçäo, valores de 10,00 mais ou menos 0,50 min, 3,80 mais ou menos 2,10 ml e 15,00 mais ou menos 0,20 x 10 elevado à sexta potência sptz/ml. Na mesma ordem, o sêmen näo fracionado apresentou os seguintes valores: 15,00 mais ou menos 0,40 min, 6,48 mais ou menos 4,32 ml e 53 mais ou menos 2,10 x 10 elevado à sexta potência sptz/ml. Tempo de ejaculaçäo, volume e concentraçäo diferiram estatisticamente (P<0,05) em relaçäo às fraçöes e ao sêmen total. As anormalidades espermáticas apresentaram 15,73 mais ou menos 9,05 por cento de defeitos totais, snedo 5,74 mais ou menos 3,81 por cento de defeitos maiores e 9,99 mais ou menos 5,24 por cento de defeitos menores. Näo houve diferença significativa entre as características seminais dos ejaculados segundo o peso dos animais (abaixo ou acima de 20 kg de peso corporal), exceto quanto ao volume seminal