Diseases of the Tendons and Tendon Sheaths

Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis.

SNPs for parentage testing and traceability in globally diverse breeds of sheep

DNA-based parentage determination accelerates genetic improvement in sheep by increasing pedigree accuracy. Single nucleotide polymorphism (SNP) markers can be used for determining parentage and to provide unique molecular identifiers for tracing sheep products to their source. However, the utility of a particular "parentage SNP" varies by breed depending on its minor allele frequency (MAF) and its sequence context. Our aims were to identify parentage SNPs with exceptional qualities for use in globally diverse breeds and to develop a subset for use in North American sheep. Starting with genotypes from 2,915 sheep and 74 breed groups provided by the International Sheep Genomics Consortium (ISGC), we analyzed 47,693 autosomal SNPs by multiple criteria and selected 163 with desirable properties for parentage testing. On average, each of the 163 SNPs was highly informative (MAF≥0.3) in 48±5 breed groups. Nearby polymorphisms that could otherwise confound genetic testing were identified by whole genome and Sanger sequencing of 166 sheep from 54 breed groups. A genetic test with 109 of the 163 parentage SNPs was developed for matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry. The scoring rates and accuracies for these 109 SNPs were greater than 99% in a panel of North American sheep. In a blinded set of 96 families (sire, dam, and non-identical twin lambs), each parent of every lamb was identified without using the other parent's genotype. In 74 ISGC breed groups, the median estimates for probability of a coincidental match between two animals (PI), and the fraction of potential adults excluded from parentage (PE) were 1.1×10(-39) and 0.999987, respectively, for the 109 SNPs combined. The availability of a well-characterized set of 163 parentage SNPs facilitates the development of high-throughput genetic technologies for implementing accurate and economical parentage testing and traceability in many of the world's sheep breeds.

Congenital nasolacrimal duct fistula in Brown Swiss cattle

BACKGROUND An increased incidence of nasolacrimal duct fistula in the offspring of dam J and three of her sons (bulls A, B and C) prompted a study to investigate the prevalence and clinical manifestation of this anomaly. The dam J, bull B, 255 direct offspring of bulls A, B, and C and eight other direct and indirect offspring of cow J were examined. The periocular region of each animal was examined for unilateral or bilateral nasolacrimal duct fistula and the location, appearance and size of the lesions. RESULTS Of 265 cattle examined, 54 had unilateral (n = 24) or bilateral fistula (n = 30). The prevalence of affected offspring differed significantly among the three bulls. The fistulae were located medial to the medial canthus of the eye and were 1 to 10 mm (median, 1 mm) in height and 1 to 12 mm (median, 2 mm) in length. The shape of the opening was circular in 58, oval in 23 and slit-like in three. One other animal had a large opening with an atypical shape and another had an abnormal medial canthus with several fistulous openings. Seventy openings were pigmented and 52 were hairless. The fistulae were clinically significant in 12 animals. CONCLUSIONS The findings suggest a hereditary cause of nasolacrimal duct fistula in Brown Swiss cattle.

DNA-based diagnosis of rare diseases in veterinary medicine: a 4.4 kb deletion of ITGB4 is associated with epidermolysis bullosa in Charolais cattle.

BACKGROUND Rare diseases in livestock animals are traditionally poorly diagnosed. Other than clinical description and pathological examination, the underlying causes have, for the most part, remained unknown. A single case of congenital skin fragility in cattle was observed, necropsy, histological and ultrastructural examinations were carried out and whole genome sequencing was utilized to identify the causative mutation. RESULTS A single purebred female Charolais calf with severe skin lesions was delivered full-term and died spontaneously after birth. The clinical and pathological findings exactly matched the gross description given by previous reports on epitheliogenesis imperfecta and epidermolysis bullosa (EB) in cattle. Histological and ultrastructural changes were consistent with EB junctionalis (EBJ). Genetic analysis revealed a previously unpublished ITGB4 loss-of-function mutation; the affected calf was homozygous for a 4.4 kb deletion involving exons 17 to 22, and the dam carried a single copy of the deletion indicating recessive inheritance. The homozygous mutant genotype did not occur in healthy controls of various breeds but some heterozygous carriers were found among Charolais cattle belonging to the affected herd. The mutant allele was absent in a representative sample of unrelated sires of the German Charolais population. CONCLUSION This is the first time in which a recessively inherited ITGB4 associated EBJ has been reported in cattle. The identification of heterozygous carriers is of importance in avoiding the transmission of this defect in future. Current DNA sequencing methods offer a powerful tool for understanding the genetic background of rare diseases in domestic animals having a reference genome sequence available.

Modern techniques for the analysis of chromatin and nuclear organization in C. elegans.

In recent years, Caenorhabditis elegans has emerged as a new model to investigate the relationships between nuclear architecture, cellular differentiation, and organismal development. On one hand, C. elegans with its fixed lineage and transparent body is a great model organism to observe gene functions in vivo in specific cell types using microscopy. On the other hand, two different techniques have been applied in nematodes to identify binding sites for chromatin-associated proteins genome-wide: chromatin immunoprecipitation (ChIP), and Dam-mediated identification (DamID). We summarize here all three techniques together as they are complementary. We also highlight strengths and differences of the individual approaches.

Linking Ah receptor mediated effects of sediments and impacts on fish to key pollutants in the Yangtze Three Gorges Reservoir, China – A comprehensive perspective

The Three Gorges Reservoir (TGR), created in consequence of the Yangtze River's impoundment by the Three Gorges Dam, faces numerous anthropogenic impacts that challenge its unique ecosystem. Organic pollutants, particularly aryl hydrocarbon receptor (AhR) agonists, have been widely detected in the Yangtze River, but only little research was yet done on AhR-mediated activities. Hence, in order to assess effects of organic pollution, with particular focus on AhR-mediated activities, several sites in the TGR area were examined applying the "triad approach". It combines chemical analysis, in vitro, in vivo and in situ investigations to a holistic assessment. Sediments and the benthic fish species Pelteobagrus vachellii were sampled in 2011/2012, respectively, to identify relevant endpoints. Sediment was tested in vitro with the ethoxyresorufin-O-deethylase (EROD) induction assay, and in vivo with the Fish Embryo Toxicity Test and Sediment Contact Assay with Danio rerio. Activities of phase I (EROD) and phase II (glutathione-S-transferase) biotransformation enzymes, pollutant metabolites and histopathological alterations were studied in situ in P. vachellii. EROD induction was tested in vitro and in situ to evaluate possible relationships. Two sites, near Chongqing and Kaixian city, were identified as regional hot-spots and further investigated in 2013. The sediments induced in the in vitro/in vivo bioassays AhR-mediated activities and embryotoxic/teratogenic effects - particularly on the cardiovascular system. These endpoints could be significantly correlated to each other and respective chemical data. However, particle-bound pollutants showed only low bioavailability. The in situ investigations suggested a rather poor condition of P. vachellii, with histopathological alterations in liver and excretory kidney. Fish from Chongqing city exhibited significant hepatic EROD induction and obvious parasitic infestations. The polycyclic aromatic hydrocarbon (PAH) metabolite 1-hydroxypyrene was detected in bile of fish from all sites. All endpoints in combination with the chemical data suggest a pivotal role of PAHs in the observed ecotoxicological impacts.