Silver Carp Bone Powder as Natural Calcium for Fish Sausage

Although silver carp bones (SCB) are generated as waste, they are a natural source of calcium and have the potential to be a food ingredient. When the SCB had been soaked in hot sodium hydroxide (0.8%), autoclaved, and ground into SCB powder (SCBP), the total calcium content, analyzed by inductive coupled plasma-optical emission spectroscopy, was about 32%. X-ray absorption near-edge structure (XANES) spectroscopy specified hydroxyapatite as the major calcium component. The soluble calcium in SCBP was found to be 0.59% in de-ionized water. SCBP induced the cross-linking of proteins in minced fish after incubation at 40°C, as indicated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Fortification of SCBP at 0.0, 0.5, and 1.0% (w/w) in fish emulsion sausage resulted in a decrease of moisture content, while the fat and protein contents increased slightly. Total ash content in the sausage increased significantly, and total calcium content increased 15-fold in fortified SCBP. The hardness and gumminess values of sausage were improved with the addition of SCBP, while the microstructure was not altered by SCBP.     

Molecular epidemiology of bovine viral diarrhoea during the final phase of the Swedish BVD-eradication programme

The Swedish BVD-eradication programme has been successfully running since 1993 and is now in its final phase. Nevertheless, new infections are occasionally being detected. In this paper we describe the first results of a programme where we apply a molecular-epidemiological approach to trace sources and routes of BVDV infection, and that we expect will speed up the final phase of the BVD-programme and help to reach total eradication.     

Bovine herpesvirus type 1 (BHV-1) and bovine viral diarrhoea virus (BVDV) infections in dairy herds: self clearance and the detection of seroconversions against a new atypical pestivirus

The epidemiology of bovine herpesvirus type 1 (BHV-1) and bovine viral diarrhoea virus (BVDV) was studied in a population of small dairy herds that had not been vaccinated. Bulk tank milk samples of 186 herds in Thailand were collected four times between 2002 and 2004. Serum samples from individual animals in 11 herds were also taken on three occasions. The prevalence of BHV-1 in the 186 herds was 61% in 2002, decreasing to 48% in 2004 and for BVDV was 91% in 2002, decreasing to 72% in 2004. A BVDV antigen-positive calf was found in one of the 11 herds, and animals in this herd and three other herds seroconverted to a recently described atypical BVDV strain (HoBi). This study showed a significantly decreasing prevalence for both BHV-1 and BVDV due to a self-clearance process. Further studies are needed to find out how the atypical BVDV strain entered the cattle population.     

Virus recovery and full-length sequence analysis of atypical bovine pestivirus Th/04_KhonKaen

Phylogenetic analysis of recently identified “atypical” bovine pestiviruses, performed based on different gene regions, has revealed unclear relationships with other established species, therefore, their phylogenetic position could not be determined so far. In this study, the atypical pestivirus Th/04_KhonKaen was recovered from serum of a naturally infected calf and the complete genome sequence was determined and analysed, as means to define its position. The viral genome is 12,337 nucleotides (nt) long, and comprises a 5′-UTR of 383 nt, a 3′-UTR of 254 nt and an open reading frame of 11,700 nt, without duplication of viral sequences or insertions of cellular sequences. The phylogenetic analyses of the full-length sequence, performed by Neighbor-joining, Maximum likelihood, and the Bayesian approach, unanimously placed Th/04_KhonKaen in a single lineage, distinct from the established pestivirus species, and close to bovine viral diarrhea virus types 1 and 2. Furthermore, Th/04_KhonKaen and two previously reported atypical pestiviruses D32/00_‘HoBi’ and CH-KaHo/cont formed a well-supported monophyletic clade in trees based on the complete N^pro and E2 gene regions. The finding provides conclusive classification of the Th/04_KhonKaen virus and confirms the standing of the “atypical” bovine pestiviruses as a novel pestivirus species.     

Natural infection of cattle with an atypical 'HoBi'-like pestivirus--implications for BVD control and for the safety of biological products

During a study on Bovine Viral Diarrhoea (BVD) epidemiology in Thailand, a pestivirus was detected in serum from a calf. Comparative nucleotide sequence analysis showed that this virus was closely related to a recently described atypical pestivirus (D32/00_'HoBi') that was first isolated from a batch of foetal calf serum collected in Brazil. The results from virus neutralisation tests performed on sera collected from cattle in the herd of the infected calf, showed that these cattle had markedly higher antibody titres against the atypical pestivirus 'HoBi' than against Bovine Viral Diarrhoea Virus types 1 and 2, or Border Disease Virus. The results also supported, consequently, the results from the molecular analysis, and demonstrated that a 'HoBi'-like pestivirus had been introduced to, and was now circulating in the herd. This study is the first to report a natural infection in cattle with a virus related to this atypical pestivirus, and it suggests that this group of pestiviruses may already be spread in cattle populations. The findings have implications for BVD control and for the biosafety of vaccines and other biological products produced with foetal calf serum. Consequently, these atypical pestiviruses should be included in serological assays, and any diagnostic assay aimed at detection of pestiviruses in biological products or animals should be tested for its ability to detect them.