RESUMO
Enterotoxemia caused by Clostridium perfringens type D usually affects sheep and goats ≥ 2-wk-old. The main clinical signs and lesions of the disease are produced by the epsilon toxin (ETX) elaborated by this microorganism. However, ETX is produced in the form of a mostly inactive prototoxin that requires protease cleavage for activation. It has traditionally been believed that younger animals are not affected by type D enterotoxemia given the low trypsin activity in the intestinal content associated with the trypsin-inhibitory action of colostrum. Two Nigerian dwarf goat kids, 2- and 3-d-old, with a history of acute diarrhea followed by death, were submitted for postmortem examination and diagnostic workup. Autopsy and histopathology revealed mesocolonic edema, necrosuppurative colitis, and protein-rich pulmonary edema. Alpha toxin and ETX were detected in intestinal content, and C. perfringens type D was isolated from the colon of both animals. The isolates encoded the gene for lambda toxin, a protease that has been shown previously to activate ETX in vitro. Type D enterotoxemia has not been reported previously in neonatal kids, to our knowledge, and we suggest that lambda toxin activated the ETX.
Assuntos
Clostridium perfringens , Doenças dos Ovinos , Ovinos , Animais , Clostridium perfringens/fisiologia , Enterotoxemia/diagnóstico , Enterotoxemia/patologia , Cabras , Tripsina , Peptídeo HidrolasesRESUMO
Diarrhea and disorders in young goats are serious threats to the animals' health, influencing the profitability of the goat industry. There is a need to better understand the potential biomarkers that can reflect the mortality and morbidity in neonatal diarrhea goats. Ten pairs of twin kid goats from the same does (one healthy and the other diagnosed as diarrhea) with the same age under 14 days after birth were used in this study. Since gastrointestinal infection is probably the first ailment in neonatal goats, we aimed to investigate the changes in oxidative stress, inflammation, and gene expression in the gastrointestinal tract of neonatal diarrhea goats based on an epidemiological perspective. The results showed the activity of glutathione peroxidase (GSH-Px) was less (P < 0.05) in the jejunum in neonatal diarrhea goats compared with control goats. However, the malondialdehyde (MDA) activities in the jejunum and ileum were higher (P < 0.05) in neonatal diarrhea goats. There was no significant difference in the super-oxide dismutase (SOD) and catalase (CAT) activity observed between the two groups (P > 0.05). For the concentrations of intestinal interleukin-2 (IL2) and interleukin-6 (IL6), only the IL-2 in ileum of neonatal diarrhea goats was higher than that from healthy control goats. The transcriptomic analysis of the jejunum showed a total of 364 differential expression genes (DEGs) identified in neonatal diarrhea goats compared with control goats. The Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis of up-regulated DEGs was mainly related to the ECM-receptor interaction and axon guidance, and the down-regulated DEGs mainly related to the Arachidonic acid metabolism, complement and coagulation cascades, and alpha-Linolenic acid metabolism. Real-time PCR results showed that the expression of most toll-like receptor-4-(TLR4) pathway-related genes and intestinal barrier function-related genes were similar in the two groups. These results suggest that neonatal diarrhea goats experienced a higher intestinal oxidative stress compared with control goats. Thus, it is possible that the antioxidant capacity of young ruminants acts as an indicator of health status and the measurements of oxidation stress may be useful as diagnostic biomarkers, reflecting the mortality and morbidity in neonatal diarrhea goats.