Prevalence and molecular characterization of Cryptosporidium spp. in pre-weaned diarrheic dairy calves and their bedding materials in northern China.

Cryptosporidiosis, primarily caused by Cryptosporidium parvum, is a significant cause of diarrhea in pre-weaned dairy calves. To investigate the prevalence of Cryptosporidium among pre-weaned diarrheic dairy calves and identify potential sources of infection in northern China, 234 fecal samples from 18 farms in six regions were analyzed for Cryptosporidium. Furthermore, 217 bedding samples from both occupied and unoccupied calf hutches, heating lamp pens, and individual calving pens in eight farms in Beijing were also examined for the presence of the parasite. All samples were screened for Cryptosporidium spp. using nested PCR targeting the SSU rRNA gene fragment, and C. parvum was subtyped with nested PCR targeting the 60 kDa glycoprotein gene. The prevalence of Cryptosporidium was 33.3%, with C. parvum and C. bovis constituting 29.9% and 3.4% of cases, respectively. The positive rate of Cryptosporidium in 1- to 4-week-old calves ranged from 9.6 to 63.6%. Analysis of the gp60 fragment of C. parvum revealed four subtypes: IIdA15G1, IIdA17G1, IIdA19G1, and IIdA20G1. Besides the bedding samples in heating lamp pens, both C. parvum and C. bovis were detected in bedding samples throughout the other regions. A significant positive correlation between the detection rate of Cryptosporidium in fecal samples and that in the bedding materials of occupied calf hutches (R = 0.93, P = 0.002). These findings suggest that C. parvum is the predominant species among pre-weaned diarrheic dairy calves in northern China. Contaminated bedding materials may act as sources of infection for newborn calves.

First report of Cryptosporidium species in farmed and wild buffalo from the Northern Territory, Australia.

A molecular epidemiological survey of Cryptosporidium from water buffalo (Bubalus bubalis) in the Northern Territory in Australia was conducted. Fecal samples were collected from adult farmed (n = 50) and wild buffalo (n = 50) and screened using an 18S quantitative PCR (qPCR). Positives were typed by sequence analysis of 18S nested PCR products. The qPCR prevalence of Cryptosporidium species in farmed and wild buffalo was 30 and 12 %, respectively. Sequence analysis identified two species: C. parvum and C. bovis, with C. parvum accounting for ~80 % of positives typed from the farmed buffalo fecal samples compared to 50 % for wild buffalo. Subtyping at the 60 kDa glycoprotein (gp60) locus identified C. parvum subtypes IIdA19G1 (n = 4) and IIdA15G1 (n = 1) in the farmed buffalo and IIaA18G3R1 (n = 2) in the wild buffalo. The presence of C. parvum, which commonly infects humans, suggests that water buffaloes may contribute to contamination of rivers and waterways with human infectious Cryptosporidium oocysts, and further research on the epidemiology of Cryptosporidium in buffalo populations in Australia is required.

Diverse Genotypes of Cryptosporidium in Sheep in California, USA.

Cryptosporidium spp. is a parasite that can infect a wide variety of vertebrate species. The parasite has been detected in sheep worldwide with diverse species and genotypes of various levels of zoonotic potential and public health concern. The purpose of this study was to determine the distribution of genotypes of Cryptosporidium in sheep in California, USA. Microscopic positive samples from individual sheep from central and northern California ranches were genotyped by sequencing a fragment of the 18S rRNA gene and BLAST analysis. Eighty-eight (63.8%) of the microscopic positive samples were genotyped, and multiple genotypes of Cryptosporidium were identified from sheep in the enrolled ranches. Approximately 89% of isolates (n = 78) were C. xiaoi or C. bovis, 10% of isolates (n = 9) were C. ubiquitum, and 1% of isolates (n = 1) were C. parvum. The C. parvum and C. ubiquitum isolates were detected only from lambs and limited to four farms. Given that the majority of Cryptosporidium species (i.e., C. xiaoi and C. bovis) were of minor zoonotic concern, the results of this study suggest that sheep are not a reservoir of major zoonotic Cryptosporidium in California ranches.

A single-cohort study of Cryptosporidium bovis and Cryptosporidium ryanae in dairy cattle from birth to calving.

In order to investigate the infection dynamics of Cryptosporidium bovis and C. ryanae, a two-year prospective cohort study was performed on a dairy farm known to be free of C. parvum. Sixteen calves were recruited when newborn. Faecal samples were collected weekly until calves were nine weeks old, then monthly until calving or culling. Samples (n = 455) were examined by fluorescence microscopy, and when positive the species were determined by DNA sequencing. In calves up to nine weeks, C. bovis was found in 58.5% of the samples, C. ryanae in 9.2%, and both C. bovis and C. ryanae in 3.1%. The prevalence of shedding calves peaked at 87.5% in week five, which is earlier than many international studies have shown for C. bovis. The cumulative incidence of C. bovis reached 100% when the calves were five weeks old. In four calves, the species detected changed from C. bovis to C. ryanae or the other way around, and two samples were a combination of both species. Several individuals shed oocysts sporadically up to 16 months of age. The highest oocysts per gram faeces count was seen in week three (3.6 × 106 OPG). Diarrhoea was not associated with oocyst shedding.

Bovine cysticercosis in Ethiopia: A systematic review and meta-analysis of prevalence from abattoir-based surveys.

Ethiopia is well known for its huge livestock resource that stands number one in Africa and 10th in the world. However, cattle production is constrained by inadequate nutrition, disease, lack of support services and inadequate information. This systematic review and meta-analysis of prevalence of C. bovis in Ethiopia aims to provide a national level prevalence of the parasite from reports conducted in different parts of the country. Due to the expected variation between studies, a random-effects meta-analysis was carried out using the total sample size and number of positives (effect size and standard error of the effect size). Individual study prevalence estimates ranged from 0% to 20% with an overall pooled prevalence of 7% (95% CI = 5%-8%). Studies weighted approximately equal with weights on individual studies ranging from 2% to 2.6% due to high heterogeneity between studies. The meta-analysis indicated that between-study variability was high (τ2 = 0.001; heterogeneity I2 = 99.20% with Heterogeneity chi-square = 4974.9 and, an associated p-value of 0.01). This parasite is indicated to be one of the causes of organ condemnation causing losses of million dollars annually in the country.