Prevalence and Molecular Characterization of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in Diarrheic and Non-Diarrheic Calves from Ningxia, Northwestern China.

Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are significant parasitic gastrointestinal pathogens with global distribution in humans and domestic animals, including calves. The main symptoms of calf infection are severe diarrhea, dehydration, growth retardation, and sometimes even death. To date, there has been limited information on the prevalence of Cryptosporidium spp., G. duodenalis, and E. bieneusi infections in calves in Ningxia, China, especially between diarrheic and non-diarrheic calves. A total of 438 fecal samples were collected from diarrheic (201) and non-diarrheic (237) calves in Ningxia. PCR and DNA sequencing were used to find the prevalence of Cryptosporidium spp. at 46.8% (205/438), G. duodenalis at 16.9% (74/438), and E. bieneusi at 10.0% (44/438). The prevalence of Cryptosporidium spp. infection in diarrheic and non-diarrheic calves was 54.0% (128/237) and 38.3% (77/201), respectively, and statistical analysis showed a positive correlation between the prevalence of Cryptosporidium spp. infection and calf diarrhea (p < 0.01). However, in this study, there was no statistical correlation between the prevalence of G. duodenalis infection as well as E. bieneusi infection and calf diarrhea (p > 0.05). Furthermore, four known Cryptosporidium species were successfully identified by comparing them with SSU rRNA gene sequences, including C. parvum, C. bovis, C. ryanae, and C. andersoni. In addition, all 74 G. duodenalis-positive samples were identified as assemblage E by comparative analysis of bg gene sequences. Among the 44 E. bieneusi-positive samples sequenced in the present study, 4 distinct E. bieneusi genotypes were successfully identified by comparative analysis of ITS sequences, including 3 known genotypes (J, BEB4, and N) and 1 novel genotype, the latter of which was identified and designated as NX1. These findings indicated that the high genetic diversity and complex population structures of Cryptosporidium spp., G. duodenalis, and E. bieneusi in Ningxia diarrhea calves and non-diarrhea calves, which provide new data for understanding the epidemiological status of Cryptosporidium spp., G. duodenalis, and E. bieneusi in Ningxia calves.

Detection of the dominant pathogens in diarrheal calves of Ningxia, China in 2021-2022.

Introduction: Calf diarrhea is a complex disease that has long been an unsolved problem in the cattle industry. Ningxia is at the forefront of China in the scale of cattle breeding, and calf diarrhea gravely restricts the development of Ningxia's cattle industry. Methods: From July 2021 to May 2022, we collected diarrhea stool samples from calves aged 1-103 days from 23 farms in five cities in Ningxia, and performed PCR using specific primers for 15 major reported pathogens of calf diarrhea, including bacteria, viruses, and parasites. The effect of different seasons on the occurrence of diarrhea in calves was explored, the respective epidemic pathogens in different seasons were screened, and more detailed epidemiological investigations were carried out in Yinchuan and Wuzhong. In addition, we analyzed the relationship between different ages, river distributions and pathogen prevalence. Results: Eventually, 10 pathogens were detected, of which 9 pathogens were pathogenic and 1 pathogen was non-pathogenic. The pathogens with the highest detection rate were Cryptosporidium (50.46%), Bovine rotavirus (BRV) (23.18%), Escherichia coli (E. coli) K99 (20.00%), and Bovine coronavirus (BCoV) (11.82%). The remaining pathogens such as Coccidia (6.90%), Bovine Astrovirus (BoAstV) (5.46%), Bovine Torovirus (BToV) (4.09%), and Bovine Kobuvirus (BKoV) (3.18%) primarily existed in the form of mixed infection. Discussion: The analysis showed that different cities in Ningxia have different pathogens responsible for diarrhea, with Cryptosporidium and BRV being the most important pathogens responsible for diarrhea in calves in all cities. Control measures against those pathogens should be enforced to effectively prevent diarrhea in calves in China.

Potential prognostic markers of retained placenta in dairy cows identified by plasma metabolomics coupled with clinical laboratory indicators.

The complex etiopathology of retained placenta (RP) and hazards associated with it has made it crucial for researchers and clinical veterinarians to study pathogenesis, early-warning diagnosis, and treatment. This study aimed to screen the potential prognostic markers of RP in dairy cows using plasma metabolomics coupled with clinical laboratory indicators. Blood samples were collected from 260 dairy cows at 21, 14, 7, and 0 days before parturition and 7, 14, and 21 days after parturition. Consequently, 10 healthy cows and 10 cows with RP with similar parity, body condition score, and age were included in the study. The changes in clinical laboratory indicators of the enrolled cows from 21 before parturition to 21 days after parturition were assessed. After initial overview of the multivariate statistical data using PCA analysis, the data were subjected to orthogonal partial least-squares discriminant analysis. Compared with cows with RP at 7 days before parturition, the levels of endothelin and 6-keto-prostaglandin F1α were increased in healthy cows, while the level of estradiol and progesterone decreased. Adenine dinucleotide phosphate, hypoxanthine, guanine dinucleotide phosphate, inosine monophosphate, and L-arginine were revealed as potential prognostic markers of cows with RP at 7 days before parturition involved in the regulation of taste transduction, purine and glutathione metabolism, and autophagy. The best period for the early-warning diagnosis of RP in dairy cows is 7 days before parturition, and purine metabolism and autophagy may play a vital role in the occurrence and development of RP in dairy cows.

Proprotein convertase subtilisin/kexin 9 inhibitors in reducing cardiovascular outcomes: a systematic review and meta-analysis.

BACKGROUND: To evaluate the effects of proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors on major adverse cardiovascular events (MACE). METHODS: Our systematic review included randomised controlled trials if they studied PCSK9 inhibitors in patients for primary and/or secondary prevention of cardiovascular diseases or with hypercholesterolaemia/hyperlipidaemia. Dichotomous variables from individual studies were pooled by relative risks (RR) and their 95% CIs using the random-effect model. Risk difference (RD) in the 10-year frame was also estimated using the pooled RR and the estimated baseline risk using the control group. Grading of Recommendation Assessment, Development and Evaluation was used to assess the quality of evidence. RESULTS: We included 54 trials with 97 910 patients in the analysis. Compared with controls, PCSK9 inhibitors significantly reduced the risk of MACE by 16% (RR, 0.84; 95% CI 0.79 to 0.89; RD: 47 fewer per 1000 vs 286 as the baseline risk; 95% CI 32 to 59 fewer), non-fatal myocardial infarction (MI) by 17% (RR, 0.83; 95% CI 0.74 to 0.93; RD, 35 fewer per 1000 vs 207 as the baseline; 95% CI 13 to 53 fewer) and any stroke by 25% (RR, 0.75; 95% CI 0.65 to 0.85; RD, 16 fewer per 1000 vs 61 as the baseline; 95% CI 9 to 21 fewer) with moderate quality evidence. No significant differences were found between PCSK9 inhibitors and control groups in all-cause mortality, cardiovascular death, heart failure or unstable angina with low-quality evidence. CONCLUSIONS: This study demonstrated that PCSK9 inhibitors could significantly reduce the risk of MACE, non-fatal MI and stroke. TRIAL REGISTRATION: PROSPERO; CRD42017073904.