Congenital cerebral and cerebellar anomalies in relation to bovine viral diarrhoea virus and Akabane virus in newborn calves.

Congenital malformations occur sporadically in cattle; however, congenital structural and functional disorders of the nervous system are rather common in ruminants. Among the numerous causes of congenital nervous system defects, infectious agents are highlighted in this paper. Virus-induced congenital malformations are well known, among which those caused by bovine viral diarrhoea virus (BVDV), Akabane virus (AKAV), Schmallenberg virus (SBV), Bluetongue virus (BTV), and Aino virus (AV) are the most studied. In this study, we specify and categorise macroscopic and histopathological lesions in the brain of 42 newborn calves suffering from severe neurologic signs and diagnosed with BVDV and AKAV infection. Following a complete necropsy, specimens were collected from the brains to track the presence of BVDV, AKAV and SBV utilising reverse transcription polymerase chain reaction. Of the 42 examined calves, 21 were BVDV positive and 6 were AKAV positive, while 15 brains were negative for the studied agents. Regardless of the aetiology, cerebellar hypoplasia, hydranencephaly, hydrocephalus, porencephaly, and microencephaly were detected. Cerebellar hypoplasia was the most common lesion seen in both BVDV-positive and AKAV-positive cases. Virus-induced necrosis of the germinative cells of the external granular layer of cerebellum, as well as vascular damages, are believed to be the underlying causes of cerebellar hypoplasia. BVDV was the most important aetiological agent of such cases in this study.

Effect of Exogenous Progesterone or Flunixin Meglumine After AI on Serum Progesterone Concentration and Pregnancy per AI in Lactating Dairy Cows.

The objective of this study was to determine the effect of post AI administration of exogenous progesterone (P4) or a prostaglandin F2α (PGF2α) synthesis inhibitor agent on serum P4 concentrations and pregnancy per AI (P/AI) in lactating dairy cows. Eighty lactating cows were randomly allocated to one of four treatment groups: 1) CON (control), received 5 mL of saline solution on d 6 and 14 post AI; 2) IP4 (injection of P 4), received 125 mg of P4 im on d 6 and 14 post AI; 3) CIDR, received a controlled internal drug release insert containing 1.38g of P4 from d 6 to 20 post AI; and 4) FM (Flunixin Meglumine), received 0.625 g of Flunixin Meglumine, a nonsteroidal anti-inflammatory drug, twice daily on d 15 and 19 post AI. Blood samples were taken on d 0, 6, 14, 17 and 20 post AI to determine P4 concentrations. Transrectal palpation was performed between 40 and 45 d post AI to determine pregnancy status. All treatment groups (i.e. IP4, CIDR and FM) resulted in greater serum P4 concentration on d 17 and 20 post AI compared to CON (P < 0.05). Cows given a CIDR insert had greater concentrations of P 4 on d 17 and 20 than IP4 and FM cows (P < 0.05). However, no significant difference was found between IP4 and FM groups for serum P4 concentrations. The P/AI was greater (P < 0.05) in CIDR-treated cows (55%, 11/20) than CON (25%, 5/20), and intermediate in IP4 (40%, 8/20) and FM (35%, 7/20) cows. In summary, treatment with exogenous P4 (i.e. CIDR and IP4) or FM increased serum P4 concentrations in lactating dairy cows. However, results suggest that only CIDR administration would improve P/AI.