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Coronaviruses (CoVs) produce a wide spectrum of disease syndromes in different mammalian
and avian host species. These viruses are well-recognized for their ability to change tissue
tropism, to hurdle the interspecies barriers and to adapt ecological variations. It is predicted
that the inherent genetic diversity of CoVs caused by accumulation of point mutations and
high frequency of homologous recombination is the principal determinant of these competences. Several CoVs (e.g. Severe acute respiratory syndrome-CoV, Middle East respiratory
syndrome-CoV) have been recorded to cross the interspecies barrier, inducing different disease conditions in variable animal hosts. Bovine CoV (BCoV) is a primary cause of gastroenteritis and respiratory disease in cattle calves, winter dysentery in lactating cows and
shipping fever pneumonia in feedlot cattle. Although it has long been known as a restrictive
cattle pathogen, CoVs that are closely related to BCoV have been recognized in dogs, humans
and in other ruminant species. Biologic, antigenic and genetic analyses of the so-called
‘bovine-like CoVs’ proposed classification of these viruses as host-range variants rather
than distinct virus species. In this review, the different bovine-like CoVs that have been identified in domesticated ruminants (water buffalo, sheep, goat, dromedary camel, llama and
alpaca) and wild ruminants (deer, wild cattle, antelopes, giraffes and wild goats) are discussed
in terms of epidemiology, transmission and virus characteristics. The presented data denote
the importance of these viruses in the persistence of BCoV in nature, spread to new geographical zones, and continuous emergence of disease epidemics in cattle farms.

The mammalian oviduct is a complex, fibromuscular organ known for its role in orchestrating a series of timely and dynamic changes to suitably support early embryogenesis. Climate change-induced heat stress (HS) is one of the largest single stressors compromising reproductive function in humans and farm animals via systemic changes in the redox status of the maternal environment, adversely affecting fertilization and early embryonic development. Oviductal organoids represent a unique 3-dimensional, biomimetic model to study the physiology of the oviduct and its subsequent impact on embryo development under various environmental conditions.

BACKGROUND: Currently, non-valved conduits are preferred for extracardiac total cavo-pulmonary connection (TCPC). However, previous work has failed to provide objective data comparing the postoperative outcome between non-valved TCPCs and bovine jugular vein valved xenograft (BJV) TCPCs. Hence, the objective of this study is to compare the postoperative outcomes in extracardiac TCPC patients who received BJV vs synthetic non-valved conduits and evaluate the effect of BJV on liver fibrosis.

METHODS: Of 206 patients who had extracardiac TCPC from 2002 to 2017 were divided into three groups. Group A (n = 66) received BJV, group B (n = 37) received PET conduits and group C (n = 103) received polytetrafluoroethylene (PTFE) tube. Study endpoints were hospital outcomes, conduits thrombosis, reinterventions, and survival. Liver stiffness and fibrosis were assessed in eight patients with BJV.

RESULTS: Preoperative parameters were comparable among groups. Thrombosis was significantly lower in group C (P < .0003) but no difference between groups A and B (P = .951). Reinterventions did not differ significantly among groups (Log-rank P = .598). Hospital deaths occurred in seven patients (3.4%). There was no difference in survival between groups (Log-rank P = .221). The median liver stiffness score was 18.65 kPa and the eight patients had advanced liver fibrosis (grade F3-4) in group A.

CONCLUSION: PTFE is the recommended conduit for TCPC with a lower risk of thrombosis compared to BJV and PET. BJV conduits in TCPC circuits may not protect against liver fibrosis. BJV should not be considered as an option for TCPC.

In present study, we sought to examine the ability of preimplantation bovine embryos to activate the NF-E2-related factor 2 (NRF2)-mediated oxidative-stress response under an oxidative stress environment. In vitro 2-, 4-, 8-, 16-cell-, and blastocyst-stage embryos were cultured under low (5%) or high (20%) oxygen levels. The expression of NRF2, KEAP1 (NRF2 inhibitor), antioxidants downstream of NRF2, and genes associated with embryo metabolism were analysed between the embryo groups using real-time quantitative PCR. NRF2 and Keap1 protein abundance, mitochondrial activity, and accumulation of reactive oxygen species (ROS) were also investigated in blastocysts of varying competence that were derived from high or low oxygen levels. The expression levels of NRF2 and its downstream antioxidant genes were higher in 8-cell, 16-cell, and blastocyst stages under high oxygen tension, whereas KEAP1 expression was down-regulated under the same conditions. Higher expression NRF2 and lower ROS levels were detected in early (competent) blastocysts compared to their late (non-competent) counterparts in both oxygen-tension groups. Similarly, higher levels of active nuclear NRF2 protein were detected in competent blastocysts compared to their noncompetent counterparts. Thus, the survival and developmental competence of embryos cultured under oxidative stress are associated with activity of the NRF2-mediated oxidative stress response pathway during bovine pre-implantation embryo development.