Evaluation of some etiological factors predisposing to diarrhoea in lambs in "La Serena" (Southwest Spain)

Etiological and Pathomorphological Investigations of Coronavirus and Rotavirus Gastroenteritis in Goat Kids and Lambs

The aim of the performed field and laboratory investigations was to determine the commonest enteropathogens in neonatal and juvenile lambs and goat kids, as well as induced macro- and microscopic alterations in the different digestive system compartments. The study comprised a total of 850 newborn and juvenile lambs (600) and goat kids (250) from 9 private dairy farms (3 goat farms, 6 sheep farms). The age of animals was from 24 hours to 20 days. The following rapid antigen detection tests were used: (Rainbow calf scour 5 BIO K 306, Monoclonal Antibody anti-Coronavirus аnd Rotavirus FITC conjugated, BIOX Diagnostics, Belgium). Gross anatomy and histopathological examination of tissue samples was performed on 21 carcasses (9 goat kids and 12 lambs) from animals that died with signs of gastroenteritis. The main detected agents of intestinal infections were Cryptosporidium parvum, rotaviruses, coronaviruses and Escherichia coli.

First report on Cryptosporidium parvum, Escherichia coli K99, rotavirus and coronavirus in neonatal lambs from north-center region, Algeria

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The etiology of neonatal diarrhea is multifactorial and remains one of the biggest problems in ruminant livestock farming. This study represent the first report in Algeria on Cryptosporidium parvum, Escherichia coli K99, rotavirus and coronavirus in the etiology of neonatal diarrhea in lambs.

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Faecal samples from 559 neonatal lambs aged less than 30 days from 30 sheepfolds were screened with pathogen-specific antigen ELISA for C. parvum, E. coli K99, rotavirus, and coronavirus.

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The prevalence of C. parvum was the highest compared to other enteric pathogens.

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In various combinations, mixed infections were detected only with C. parvum.

The etiology of neonatal diarrhea is multifactorial and remains one of the greatest health problems in sheep livestock farming. Faecal samples from 559 neonatal lambs aged less than 30 days from 30 sheepfolds located in the north-center region of Algeria were screened with pathogen-specific antigen ELISA for Cryptosporidium parvum, Escherichia coli K99, rotavirus, and coronavirus. Of the 559 lambs, 312 (58.81 %), 155 (27.72 %), 72 (12.88 %) and 20 (3.57 %) were positives for C. parvum, E. coli K99, rotavirus and coronavirus antigens, respectively. The prevalence of C. parvum was the highest (p < 0.0001). C. parvum, E. coli K99, rotavirus and coronavirus were observed in 23 (76.66 %), 17 (56.66 %), 9 (30 %) and 3 (10 %) sheepfolds, respectively. Compared to age, the prevalence of C. parvum was highest during the second and third week of age (p < 0.001). In contrast, other pathogens were found to be more frequent in lambs aged ≤7 days (p < 0.001). The number of lambs with diarrhea was 280 (50.09 %) of which 280 (100 %), 127 (45.35 %), 52 (18.57 %) and 10 (3.57 %) were found to be infected with C. parvum, E. coli K99, rotavirus and coronavirus, respectively (p < 0.0001). In various combinations, mixed infections were detected only with C. parvum. This is the first report of C. parvum, E. coli K99, rotavirus, and coronavirus in ≤30-days old neonatal lambs in Algeria. Special attention should be given to the first colostrum feeding, hygiene of the farm, prevention and control measures for a better prevention of neonatal diarrhea in lambs.

High-Throughput Sequencing Reveals the Gut Microbiome of the Bactrian Camel in Different Ages

The complex gut microbiota plays a key role in host metabolism and health. However, the core microbial communities in the different aged Bactrian camels remain totally unclear. We used high-throughput 16S rRNA gene sequencing to examine the temporal variability of the fecal microbiota in Bactrian camels. At 2 months of age, the fecal microbiota was composed of Firmicutes, Proteobacteria, and Actinobacteria. At 1 and 3 years of age, the fecal microbiota was dominated by Firmicutes, Bacteroidetes, and Verrucomicrobia. At the genus level, Blautia, Fusobacterium, and Bifidobacterium were more abundant at 2 months of age, as well as Escherichia-Shigella. Ruminococcaceae_UCG-005, Akkermansia, and Christensenellaceae_R-7_group were the most abundant at 1 and 3 years of age. Diversity and stability of the gut microbiota increased with age. There was enrichment for genes associated with immune system diseases at 2 months of age. This study is the first to investigate the distribution of the gut microbiota in Bactrian camels with different ages and provide a baseline for future camel microbiology research.

Dynamic Distribution of Gut Microbiota in Goats at Different Ages and Health States

The importance of the gut microbiota (GM) of animals is widely acknowledged because of its pivotal roles in metabolism, immunity, and health maintenance. The level of health can be reflected by the dynamic distribution of GM. In this study, high-throughput sequencing of the bacterial 16S rRNA gene was used to compare the microbial populations from feces in healthy and diarrheic kids, which reflected the dynamic shift of microbiota in kids and investigated differences from adult healthy goats. Healthy kids and goats not only displayed higher species richness but also exhibited higher bacterial diversity than diarrheic kids based on the results of the operational taxonomic unit analysis, alpha diversity, and beta diversity. Firmicutes and Bacteroidetes were the most dominant phyla in all samples. At the genus level, the differences in diversity and abundance between diarrheic kids and the other two groups were gradually observed. In the diarrheic kid intestine, Bacteroides remained the dominant species, and the proportion of Clostridium_sensu_stricto_1 and Paeniclostridium increased, whereas Rikenellaceae_RC9_gut_group, Ruminococcaceae_UCG-005, and Christensenellaceae_R-7_group were significantly reduced. The results showed the differences of GM in diarrheic kids and healthy kids were significant while in kids and goats were not obvious. Differences in the composition of intestinal microbiota may not be the cause of diarrhea, and some changes of bacterial richness may guide our interpretation of diarrhea. This study is the first to investigate the distribution of GM in Boer goats with different ages and health states. Furthermore, this study will provide a theoretical basis for the establishment of a prevention and treatment system for goat diarrhea.

Relationship between the treatment and the evolution of the clinical course in scouring Merino lambs from "La Serena" (Southwest Spain)

This work investigated the link between the type of treatment and the clinical evolution of lambs suffering from diarrhoea attributed to non-enterotoxigenic Escherichia coli. Two hundred and forty scouring lambs, and 25 healthy lambs selected as control, were used in this trial. The faecal samples from the scouring lambs were positive to non-enterotoxigenic E. coli. All the scouring lambs received supportive care and they were randomly allotted to two groups of 120 animals (treated group and untreated group). The lambs in the treated group were given two daily doses of 20 mg/kg live weight spectinomycin for 3 days, while the other group of lambs (untreated group) did not receive any antibiotic. Serum endotoxin was higher in the treated lambs. The combined infection of E. coli + Proteus mirabilis was the most frequent microbiological result in the deceased treated lambs, while the only enteric pathogen isolated in the untreated lambs submitted to necroscopy was E. coli. The pathological findings most commonly recorded in the untreated lambs were suggestive of a generalized inflammatory process attributed to colibacilosis, while the lesions in the treated lambs might correspond to an enterotoxoemic process. The overproduction of P. mirabilis might be consequence of the antibiotic treatment and it would be the most probable cause of the endotoxemia, the high mortality rate and the pathological findings in the treated lambs. Therefore, a supportive care without antibiotics does not lead to a poorer chance of survival in lambs with diarrhoea attributed to non-enterotoxigenic E. coli.