Two studies were done to study detoxification of aflatoxin (AF)-contaminated chick feed with Nocardia corynebacteroides (NC). In the first study, pathogenicity of the bacteria was studied; in the second, the nutritional value of detoxified feed was evaluated. Commercial corn was divided into 2 sublots, one of which was contaminated with AF. Both lots were divided into 2 parts; the first was inoculated with NC. Four corn-soybean diets were prepared from the 4 corn lots. A completely randomized design was used with 2 x 2 factorial arrangement in which the factors were AF contaminated or not and NC inoculated or not. One hundred Ross 308 chicks (1-d-old, male) were used in 4 treatments with 5 repetitions and 5 chickens per cage. Bird weight and feed consumption were recorded weekly. Each week, 1 chick per treatment repetition was killed for histopathologic analysis of liver, kidney, bursa of Fabricius, pancreas, and small intestine (duodenum, jejunum, and ileum) and for analysis by scanning electron microscopy of the 3 sections of the intestine. At 21 d (the end of both experiments), 1 chick per treatment repetition was killed, and moisture, lipid content, and residual AF in liver were detected. Results at 3 wk did not show differences between treatments (P > 0.05) in any of the variables. In the second study, the same methodology was used except that greater levels of AF were used (800 and 1,200 mug of AFB1/kg of feed). Results showed differences (P < 0.05) in body weight, lipid content, and residual AF in liver. Histopathologic studies showed statistical differences in lesion severity in liver, duodenum, and kidney. Scanning electron microscopy analysis showed severe lesions of intestinal mucosa that mainly affected tight junctions in AF treatments. It can be concluded that NC is safe for chicks and may be used to partly detoxify chicken feed contaminated with AF.
Since the report of the initial outbreak of Porcine rubulavirus (PorPV) infection in pigs, only one full-length genome from 1984 (PorPV-LPMV/1984) has been characterised. To investigate the overall genetic variation, full-length gene nucleotide sequences of current PorPV isolates were obtained from different clinical cases of infected swine. Genome organisation and sequence analysis of the encoded proteins (NP, P, F, M, HN and L) revealed high sequence conservation of the NP protein and the expression of the P and V proteins in all PorPV isolates. The V protein of one isolate displayed a mutation that has been implicated to antagonise the antiviral immune responses of the host. The M protein indicated a variation in a short region that could affect the electrostatic charge and the interaction with the membrane. One PorPV isolate recovered from the lungs showed a mutation at the cleavage site (HRKKR) of the F protein that could represent an important factor to determine the tissue tropism and pathogenicity of this virus. The HN protein showed high sequence identity through the years (up to 2013). Additionally, a number of sequence motifs of very high amino acid conservation among the PorPV isolates important for polymerase activity of the L protein have been identified. In summary, genetic comparisons and phylogenetic analyses indicated that three different genetic variants of PorPV are currently spreading within the swine population, and a new generation of circulating virus with different characteristics has begun to emerge.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.