Genetic diversity and shedding profiles for Cryptosporidium parvum in adult cattle and their calves

Genetic characterisation of Cryptosporidium parvum in dairy cattle and calves during the early stages of a calving season

Cryptosporidium parvum is a causative agent of cryptosporidiosis, an infectious gastroenteritis in neonatal ruminants, which can be fatal in severe cases. The aim of this study was to determine the prevalence of infections in dairy cattle/calves during the early stages of a calving season and the species/genotypes of the Cryptosporidium present. Faecal samples collected from pre- and post-partum dams (n = 224) as well as calves from age ∼1 day onwards (n = 312) were examined. Oocysts were concentrated, DNA extracted and tested by Cryptosporidium 18S rRNA gene PCR and sequencing, while genotypes of C. parvum were determined by gp60 and VNTR analysis. Results showed that 31.3% and 30.4% of pre- and post-partum dams tested positive for Cryptosporidium, respectively. In the adults, C. parvum (n = 52), C. bovis (n = 4) and C. andersoni (n = 19) were identified, while in the calves 248 out of 312 (79.5%) were PCR-positive for C. parvum. The proportion of positive calf samples was significantly higher (P < 0.0001) than the proportion of positive adult cattle during the first seven weeks of the calving season. In adult cattle, three distinct gp60 genotypes were identified, a predominant genotype IIaA15G2R1 (n = 36) and genotypes IIaA15R1 (n = 2) and IIaA14G2R1 (n = 1). In the calves, only genotype IIaA15G2R1 was detected (n = 125). Although C. parvum was observed in adult cattle two weeks after the start of the calving season, the predominant genotypes were not detected until Week 4 in both adults and calves, meaning it is still unclear whether adult cattle are the initial source of C. parvum infections on the farm. Historically calves on this dairy farm demonstrated the IIaA19G2R1 genotype, which, has now clearly been replaced with the IIaA15G2R1 genotype that is now found in both adults and calves. During the study season, significantly higher levels of neonatal calf mortality were observed compared to the seasons before (P = 0.046) and after (P = 0.0002). This study has shown comparable levels of C. parvum infection in both pre- and post-partum dams but higher levels of infection in neonatal calves.

Cryptosporidium in human-animal-environment interphase at Adama and Asella areas of Oromia regional state, Ethiopia

Background

In Ethiopia, several studies have reported the occurrence of Cryptosporidium infection in young calves, lambs, and HIV positive patients. However, research on cattle and sheep of all ages, as well as humans, has been limited.

Methods

A cross-sectional study was conducted to investigate the occurrence of Cryptosporidium in dairy cattle, sheep, humans, and manure samples. Dairy cattle and sheep were stratified according to their age groups and randomly sampled. Stool samples from volunteered dairy farm workers and rural household members were collected purposefully. A semi-structured questionnaire was also used to collect information about manure handling practices and socio-demographic variables. All collected samples were processed with the sugar floatation technique and the modified Ziehl–Neelsen staining method. Logistic regression was used to analyze the association of risk factors with the occurrence of Cryptosporidium in study subjects (p < 0.05).

Results

The overall prevalence of Cryptosporidium in dairy cattle, sheep, humans, and manure samples was 20.5%, 14%, 16%, and 13.20%, respectively. Cryptosporidium infection was significantly higher in dairy cattle aged 1–12 months and 13–36 months with odds of 3.48 and 3.07 times higher, respectively, compared to others. Similarly, its occurrence was 2.69 times higher in sheep aged 1–6 months than those above 6 months. And also, a higher average oocyst count (above 10 oocysts) per-field was observed in cattle aged 1–12 months, followed by sheep aged 1–6 months. Furthermore, the likelihood of infection was 13 times greater in farm workers compared to household members of smallholder farmers. In addition, the occurrence of oocysts was 22.8 times higher in manures from dairy cattle than that of sheep. About 16.8% of the study respondents had manure disposal pit, 98.1% of them used manure as fertilizer for crop and vegetable production without any treatment.

Conclusions

The study revealed the occurrence of Cryptosporidium infection in all age groups of dairy cattle and sheep, humans engaged in animal production. Occurrence of Cryptosporidium in manure suggests it potential contamination of environment and water sources.

Epidemiological and Molecular Study of Cryptosporidium in Preweaned Calves in Kuwait

Simple Summary

Cryptosporidiosis is a global, zoonotic disease of concern. Cryptosporidium spp. can infect susceptible hosts via a main fecal–oral route due to cross-contamination of raw food and surface water from reservoir animals in the neighborhood, farms, or slaughter houses, besides some mechanical vectors, such as cockroaches and flies. Cryptosporidiumparvum alleles are the most common species infecting children, and its potential reservoir is cattle. Hence, understanding the epidemiology of Cryptosporidium spp. in preweaned calves, along with the diagnosis of the predominant species and subtypes infecting them, can play a role in preventing Cryptosporidium spp. spread in the environment. In this study, Cryptosporidiumparvum subtype IIaA15G2R1 was the most dominant Cryptosporidium spp. detected in preweaned calves in Kuwait. This subtype was recorded previously in Kuwaiti children suffering from diarrhea. Maintaining good personal hygiene in humans and reducing, controlling, or eliminating the causal risk factors in preweaned calves is a superb strategy for preventing and narrowing the spread of this disease.

Abstract

Cryptosporidium is a worldwide enteric protozoan parasite that causes gastrointestinal infection in animals, including humans. The most notable species is Cryptosporidium parvum because of its zoonotic importance; it is also the leading cause of cryptosporidiosis in preweaned calves. A cross-sectional study was conducted to determine the prevalence of Cryptosporidium infection, investigate the potential risk factors, and use molecular diagnosis to identify the predominant Cryptosporidium spp. in preweaned calves in Kuwait. Of 175 preweaned calves, Cryptosporidium antigens were detected in 58 (33.1%) using rapid lateral immunochromatography assay (IC). Calves less than one month of age (OR = 4.32, p = 0.0001) and poor hygiene (OR = 2.85, p = 0.0075) were identified as significant risk factors associated with Cryptosporidium infection. Molecular identification revealed that C. parvum (62.8%) was the dominant species infecting preweaned calves in Kuwait. In contrast, C. bovis and C. andersoni were recorded at 5.7% and 2.9%, respectively. All C. parvum gp60 nucleotide sequences were subtype IIaA15G2R1. Calves could be a source of C. parvum infection due to the similarity of the subtypes recorded previously in Kuwaiti children and preweaned calves in this study. Therefore, more research is needed to understand the Cryptosporidium transmission cycle in Kuwait.

Different methods of eubiotic feed additive provision affect the health, performance, fermentation, and metabolic status of dairy calves during the preweaning period

Background

This study aimed to evaluate whether different methods of providing eubiotic feed additives to neonatal calves, during the preweaning period, can improve the calves’ health, performance, ruminal fermentation, and metabolic status. Forty-four (3-day-old) Holstein–Friesian dairy calves (22 female and 22 male) were divided into four treatment groups for the duration of the 8-week trial. The eubiotic feed additive consisted of a combination of probiotic Lactobacillus spp. (multiple-strains at a dose of 250 mg/calf/day) and phytobiotics containing rosmarinic acid, as the main bioactive compound (at a dose of 50 mg/calf/day). The groups were named: CON (control, without eubiotic in either the milk replacer or the starter feed), MR (eubiotic in the milk replacer), SF (eubiotic in the starter feed), MRS (eubiotic in both the milk replacer and the starter feed). The individual intake of starter feed and the fecal scores were measured daily, and body weight and biometric measurements were taken weekly until calves were 56 days of age. Blood samples were collected on day 3 and then every 14 days to determine concentrations of insulin-like-growth-factor-I, β-hydroxybutyrate, non-esterified fatty acids, and blood urea nitrogen. Ruminal fluid was collected on days 28 and 56 for short-chain fatty acids, NH₃-N, and pH measurements.

Results

The body weight of the calves of the MR treatment group was higher compared to all other groups on days 28 and 56. Including the eubiotic feed additive in the milk replacer increased average daily gain, starter intake, and total dry matter intake from day 29 to day 56 and the overall experimental period compared to the CON group. The calves with MR treatment had lower fecal scores from days 3 to 28, a number of parasite oocysts/cysts per gram of feces on day 28, and the occurrences of fecal consistency scores of 3 (mild diarrhea) and 4 (severe diarrhea) were 3.2 and 3.0 times lower, respectively, compared with the CON group. The MR group had higher ruminal concentrations of short-chain-fatty-acids, propionate, and butyrate on day 56 than the CON group. Adding eubiotics into milk replacer resulted in the highest concentrations of blood insulin-like-growth-factor-I and β-hydroxybutyrate from days 29 to 56 and the overall experimental period.

Conclusion

The addition of eubiotic feed additives into the milk replacer can improve health, performance, ruminal fermentation, and biochemical blood indices in dairy calves during the preweaning period.