Bovine omphalocele: errors in embryonic development, veterinarian importance, and the way forward.

Omphalocele is an embryonic developmental error presented as a neonatal visceral umbilical herniation. Epidemiological and embryological studies are reviewed that revise our understanding of midgut development and defects in cattle. Google Scholar and PubMed were searched for omphalocele, exomphalos, calves, calf, cattle, epidemiology, genetics, disease presentation, and omphalocele treatments of bovine neonates. Omphalocele contains small intestine and sometimes liver and/or pyloric abomasum. This condition may arise from inadequately expanded abdominal cavity, herniated midgut entrapment, or inappropriate umbilical ring growth. Full-term neonates are otherwise healthy but comorbidities may be present. Limited epidemiological evidence suggests neonates, commonly female, of dairy dams have much higher omphalocele prevalence than humans but with fewer co-morbidities. Genetic or environmental influences may present at low incidences, especially with co-defects, while also epigenetics operate in metabolically challenged dairy cattle. Calf survival after surgical repair was commonly good if damage to eviscerated tissue was minimal and surgery prompt. Inadequate follow-ups prevented assessment of their commercial value. We also revised understanding of embryonic midgut development. There is little useful epidemiological information on bovine omphaloceles. To address this, we suggest: (i) Observations on omphaloceles should report herd and dam histories, abdominal disposition of contents, and comorbidities. (ii) Cases of surgical restitution must report full histories and thoroughly explore post-surgical follow-ups to assess animal commercial viability. There is a need for very large-scale multi-centre prospective observational studies on cattle health and productivity that should include omphaloceles.

Non-invasive endocrine monitoring indicates seasonal variations in gonadal hormone metabolites in dholes (Cuon alpinus).

To date, there is no information on reproductive endocrinology of dholes (Cuon alpinus). The objectives of the present study were as follows: (i) to characterize longitudinal profiles of gonadal steroids; and (ii) to examine the relationship between gonadal hormones and sexual behaviours in dholes. Three breeding pairs and two bachelor males were included in the study. Among these, four animals (2 males and 2 females; 4 years old) were imported from The Netherlands to Thailand 3 months before the study onset; the remaining individuals (3 males and 1 female; 5-7 years old) were native born. Faecal samples were collected 3-7 days/week for 12 months, extracted and assessed for gonadal hormone metabolites using a validated enzyme immunoassay. Observations of behaviour were conducted in 30 min sessions, 3-5 days/week. For the three breeding males, testosterone was elevated (P < 0.05) from October to January in the two imported males, whereas the concentration of steroid metabolites was high from April to June and from September to November in the native male. However, there was no clear seasonal pattern of reproductive hormone in the bachelor group. Oestrogen metabolite level of imported females was elevated for 9-12 days in January, followed by a rise in progestagen concentration. For native females, oestrogen metabolites were above the basal values in April and September, each of which was followed by a rise in progestagen concentration that remained elevated for 77 and 112 days, respectively. Sexual behaviours, including solicitation, mounting and copulations, were observed during the oestrogen peak in all females. Our findings indicate that reproductive seasonality of dholes may depend on the animals' origin and social group.

The effect of activation protocols on the development of cloned goat embryos.

This study was conducted to compare the developmental competence of somatic nuclear transfer (NT) embryos, after either ionomycin or ethanol activation, in locally bred goats. Donor cells were prepared from the ear skin fibroblasts of a female goat. Cells, at passage 3-8, starved by culturing in 0.5% FCS for 4-8 d, were used for NT. Immature oocytes were obtained from FSH-stimulated goats and matured for 22 hr before enucleation and NT. After fusion, the reconstructed embryos were activated with either ionomycin or ethanol followed by culturing in 6-dimethylaminopurine (6-DMAP) and cytochalasin B (CB), for 3 hr. In experiment I, the fused NT embryos (n=63, ionomycin and n=68, ethanol treatments, respectively) were cultured in B2 with a Vero co-culture system and their developmental competence was evaluated through to Day 9. In experiment II, the NT embryos at the 2-4 cell stage on Day 2 derived from each treatment (ionomycin n=46, and ethanol n=37), were transferred into 10 synchronous recipients. There were no significant differences between the NT embryos derived from the ionomycin and ethanol groups, in fusion (86.3% versus 82.9%), cleavage (90.5% versus 82.4%) and for morula/blastocyst development rates (9.5% versus 5.9%). Sixty percent (3/5) of the recipients from ionomycin became pregnant by midterm (2.5 mts) while only 20% (1/5) from ethanol treatment was pregnant by Day 45. The results demonstrate that activation with either ionomycin or ethanol in combination with 6-DMAP-CB treatment does not affect the development of cloned goat embryos.