Diversity of Parasitic Diarrhea Associated with Buxtonella Sulcata in Cattle and Buffalo Calves with Control of Buxtonellosis

Cryptosporidium spp. Infection and Genotype Identification in Pre-Weaned and Post-Weaned Calves in Yunnan Province, China

BACKGROUND

Cryptosporidium is a globally distributed zoonotic protozoan parasite in humans and animals. Infection is widespread in dairy cattle, especially in calves, resulting in neonatal enteritis, production losses and high mortality. However, the occurrence of Cryptosporidium spp. in pre- and post-weaned calves in Yunnan Province remains unclear.

METHODS

We collected 498 fecal samples from Holstein calves on 10 different farms in four regions of Yunnan Province. Nested PCR and DNA sequencing were used to determine the infection, species and genotypes of Cryptosporidium spp. in these animals.

RESULTS

The overall occurrence of Cryptosporidium spp. in Holstein calves was 32.9% (164/498), and the prevalence in pre- and post-weaned calves was 33.5% (106/316) and 31.9% (58/182), respectively. Four Cryptosporidium species were identified in these animals, namely C. bovis (n = 119), C. parvum (n = 23), C. ryanae (n = 20) and C. andersoni (n = 2). Based on sequencing analysis of the 60 kDa glycoprotein gene of C. bovis, C. parvum and C. ryanae, six subtypes of C. bovis (XXVIe, XXVIb, XXVIf, XXVIa XXVIc and XXVId), two subtypes of C. parvum (IIdA19G1 and IIdA18G1) and four subtypes of C. ryanae (XXIf, XXId, XXIe and XXIg) were identified.

CONCLUSIONS

These results provide essential information to understand the infection rate, species diversity and genetic structure of Cryptosporidium spp. populations in Holstein pre-weaned and post-weaned calves in Yunnan Province. Further, the presence of IIdA18G1 and IIdA19G1 in C. parvum implies significant animal and public health concerns, which requires greater attention and more preventive measures.

Metagenomes and Assembled Genomes from Diarrhea-Affected Cattle (Bos taurus)

The de novo metagenome assembly for C1-TPA is 68,577,389 bp long spread over 10,108 contigs, while that of C3-TPA is 55,517,929 bp distributed over 9,415 contigs. A total of 8 metagenome-assembled genomes (MAGs) were extracted from C1-TPA, and 10 were extracted from C3-TPA. Both samples have a Flavobacterium sp. and a Pseudomonas sp. in common among their bacterial communities.

The de novo metagenome assembly for C1-TPA is 68,577,389 bp long spread over 10,108 contigs, while that of C3-TPA is 55,517,929 bp distributed over 9,415 contigs. A total of 8 metagenome-assembled genomes (MAGs) were extracted from C1-TPA, and 10 were extracted from C3-TPA. Both samples have a Flavobacterium sp. and a Pseudomonas sp. in common among their bacterial communities.

Molecular and microscopic detection of natural and experimental infections of Toxocara vitulorum in bovine milk

Toxocara vitulorum is an Ascarid nematode infecting the small intestine of buffalo and cattle particularly neonate calves, with the postnatal route through milk is the main infection source. However, little is known about shedding rates and the optimum detection methods of T. vitulorum larvae in the milk of the infected bovine hosts. In this study, we aimed to evaluate the use of two methods, microscopy and PCR, and their detection limits both under the experimental and natural infection situations. In doing this, T. vitulorum eggs extracted from naturally occurring adult female worms were successfully subjected to experimental embryonation, and larvae were implemented in experimental infection of milk in ascending infection doses of 0, 1, 5, 10, 20, 50 larvae/2-ml milk samples. With the except of negative control, microscopy-based examination detected larvae in all samples, albeit with means, ranges, and the total number of larvae were detected in exponential rates relative to larvae densities in milk samples. PCR technique corresponded well to microscopy in detecting genomic DNA of T. vitulorum larvae in all milk samples down to a single larva/sample. On the other hand, and by applying the same methodology approach on 50 naturally-occurring bovine colostrum/milk samples, 13 (26%) and 20 (40%) samples were tested positive for T. vitulorum infection by microscopy and the PCR-based detection, respectively. Of these, 11 out of 26 buffalo samples (42.30%) and 2 out of 24 cow samples (8.33%) were tested positive by microscopy, while 16 (61.54%) and 3 (12.50%) of buffalo and cow samples were tested positive by PCR, respectively. By applying the Agreement Coefficient, substantial agreement (0.77) between molecular and microscopy detection was detected from all tested samples. In conclusion, larvae of T. vitulorum were unequivocally detected by microscopy and molecular methods in milk samples both under the experimental and natural field situations. Nevertheless, slightly higher rates by PCR than microscopy were obtained when detecting naturally-infected milk samples. To the best of our knowledge, this is the first in situ detection of larvae of T. vitulorum in the milk of the naturally infected animals.

Prophylactic and Therapeutic Efficacy of Prebiotic Supplementation against Intestinal Coccidiosis in Rabbits

Simple Summary

There are limitations for using chemical products in meat production. The use of prebiotics to control Eimeria infections in rabbits may be of value. Prebiotics as a prophylaxis resulted in diminishing adverse effects caused by Eimeria spp. through decreasing fecal oocyst counts, retaining body weight, and reducing the number of parasitic stages in the intestinal tissues when compared with the non-supplemented controls.

Abstract

This study was conducted to investigate the effect of prebiotic supplementation against intestinal coccidiosis in rabbits. Fifty male rabbits aged 35–60 days (1–1.5 kg) were divided into prophylactic and therapeutic experiments (five groups, 10 rabbits per group). Prophylactic experiment had prebiotic supplemented (PS-P), non-supplemented infected control (NI-P), and non-supplemented non-infected control (NN-P) groups. Ten days post-prebiotic supplementation (PPS), rabbits in groups PS-P and NI-P were infected orally with 5.0 × 10⁴ sporulated oocysts of mixed Eimeria species. However, therapeutic experiment had prebiotic supplemented (PS-T) and untreated infected (UI-T) groups of naturally infected rabbits with Eimeria species. A significant reduction in oocyst count per gram feces (OPG) (p ≤ 0.05) was reported in the PS-P (57.33 × 10³ ± 2.84) and NI-P (130.83 × 10³ ± 43.38) groups during the experiment. Additionally, rabbits in groups (PS-P, 970.33 ± 31.79 g and NI-P, 870.66 ± 6.66 g) showed weight loss after infection. However, a significant (p ≤ 0.05) decrease in OPG was observed at day seven PPS in the PS-T group (4 × 10³ ± 0.00) when compared with the UI-T group (32 × 10³ ± 7.54). Furthermore, the PS-T group had a higher body weight than rabbits in the UI-T group. Histopathological findings of the intestinal tissues (duodenum, jejunum, and ileum) showed that the counts of the endogenous stages were significantly higher in the NI-P and UI-T groups than in the prebiotic-supplemented groups (PS-P and PS-T). Supplementation of the prebiotic did not have any adverse effects on biochemical parameters, such as AST, ALT, creatinine, total protein, and total cholesterol. In conclusion, prebiotic supplementation can be used to minimize the adverse effects of intestinal coccidiosis in rabbits, which in turn limits body weight loss, especially for the prophylaxis of coccidial infection.

Prevalence of Eimeria Species in Water Buffaloes (Bubalus bubalis) from Egypt and First Report of Eimeria bareillyi Oocysts

Coccidiosis is a common disease of livestock, including water buffaloes. Reports discussing the prevalence and identity of coccidian parasites in water buffaloes from Egypt are few, and nothing is known concerning the most pathogenic species, Eimeria bareillyi. Fresh feces collected from 175 water buffaloes in Dakahlia Governorate, Egypt, were processed using the standard flotation technique. Eimerian oocysts were found in 49 (28%) samples, and 10 species were identified. Eimeria bareillyi oocysts were found in 10 samples (5.7%), and this was the single species in 3 diarrheic calves. Typical oocysts of Eimeria auburnensis with smooth oocyst walls were observed in 4 (2.3%) samples. Closely similar oocysts were found in a single sample (0.6%) together with those of E. auburnensis. These oocysts had a rough granulated or mammillated wall and are referred to as E. auburnensis-like oocysts. A molecular study is needed to clarify whether E. auburnensis and E. auburnensis-like oocysts are from different species. Other identified Eimeria species were: Eimeria alabamensis (0.6%), Eimeria bovis (10.8%), Eimeria canadensis (1.1%), Eimeria cylindrica (4%), Eimeria ellipsoidalis (2.3%), Eimeria subspherica (2.8%), and Eimeria zuernii (9.7%). This is the first report of E. bareillyi oocysts in water buffaloes from Egypt.