Serum biochemical profile and molecular detection of pathogens in semen of infertile male dromedary camels (Camelus dromedarius)

Bovine Genital Leptospirosis: An Update of This Important Reproductive Disease

Bovine leptospirosis is an important disease that affects the reproductive sphere. Due to its high relevance for the bovine production chain in a worldwide scenario, a better understanding of the disease is crucial to reduce its negative impacts. The main agents are strains from the Sejroe serogroup, such as Hardjo and Guaricura, which lead to renal and genital infection. The genital colonization causes a chronic, silent, and subclinical reproductive syndrome, called Bovine Genital Leptospirosis (BGL). Embryonic death, estrus repetition, subfertility, and abortions are the main signs of BGL condition in females. However, although leptospires have been identified in semen, the manifestation of BGL in bulls remains to be clarified. The recommended diagnosis of BGL includes a serologic screening of the herds using the microscopic agglutination test followed by PCR of genital samples (cervicovaginal mucus, uterine fragment, or semen), especially from animals with reproductive failures. After the identification of carriers, control is carried out considering three steps: antimicrobial treatment of the carriers, environmental and reproductive management, and herd vaccination. Systematic testing, quarantine of newly arrived animals, and usage of antimicrobials in semen diluents or embryo culture media are other sanitary approaches that are encouraged to improve the control of the syndrome. Herein we discuss protocols for an efficient diagnosis and preventive procedures of BGL, which are fundamental to reducing the negative impact of the disease on cattle reproduction and its consequent economic hazards.

European Regulations on Camel Germplasm Movement within the European Union: A Current Framework Based on Safety

Simple Summary

Delegated Regulation (EU) 2020/686 (hereafter Reg. 686) regulates the traceability and animal health for the movement of germinal material of camels within the EU. Given that the camel breeding industry is in a strong phase of growth, an amount of germinal material of terrestrial animals—including those belonging to the Camelidae family—is moved between the member states. The authors performed an analysis of Reg. 686 addressing veterinarians and breeders who want to sell high-quality germinal material or genetically improve their herds.

Abstract

With the aim of developing livestock breeding, the Delegated Regulation (EU) 2020/686 (hereafter referred to as Reg. 686) has taken steps to define traceability and animal health for the movement of germ material within the European Union (EU), including that of camelid species. Despite the economic importance of the camel market and the efforts of the EU to regulate their movements, there are considerable difficulties in the collection of semen and its freezing, limiting the use of artificial insemination in this species. If, on the one hand, there is little diffusion of the camel breeding and, consequently, limited diffusion of animals and germplasm, there will probably be a significant increase over the years. To avoid the spread of emerging diseases—or even those no longer present in Europe—the entry of genetic material from non-EU countries must be strictly monitored. Camels are rarely clinically compliant, but can transfer even fatal diseases to domestic ungulate farms in the EU. Based on these considerations, we conducted a narrative review of the European regulations on this issue, focusing on aspects related to their application in camels.

First serological evidence of BHV-1 virus in Algerian dromedary camels: Seroprevalence and associated risk factors

Infectious bovine rhinotracheitis (IBR), caused by bovine herpesvirus-1 (BHV-1), is a major livestock health concern in many countries of the world. The objectives of this cross-sectional study were (i) to estimate the seroprevalence of BHV-1 infection and (ii) to assess risk factors associated with this disease in dromedary camels in four districts of Algeria. Blood samples were taken from 865 camels from 84 randomly selected herds, and serum was analyzed for presence of antibodies against BHV-1 by indirect enzyme linked immunosorbent assay (ELISA). Logistic regression was used to determine associations between seroprevalence and potential risk factors (collected using a questionnaire). Antibodies against BHV-1 were detected in 3.7 % (32/865) of samples. Eighteen of 84 camel herds had at least one BHV-1 seropositive camel, giving a herd seroprevalence of 21.4 %. Based on univariate analysis, the introduction of purchased animals and contact with others animal herds appeared as major risk factors. By using multivariate analysis, the only important risk factor was introduction of new animals. This study provided, for the first time, evidence of BHV-1 infection in dromedary camels in Algeria; it also provided estimates of seroprevalence of this disease and suggests that camels may serve as a reservoir of BHV-1 for spread to other species.

Bovine viral diarrhea virus: An updated American College of Veterinary Internal Medicine consensus statement with focus on virus biology, hosts, immunosuppression, and vaccination

Control of bovine viral diarrhea virus (BVDV) in cattle populations across most of the world has remained elusive in spite of advances in knowledge about this viral pathogen. A central feature of virus perseverance in cattle herds is the unique mechanism of persistent infection. Managing BVDV infection in herds involves controlling persistently infected carrier animals using a multidimensional approach of vaccination, biosecurity, and identification of BVDV reservoirs. A decade has passed since the original American College of Veterinary Internal Medicine consensus statement on BVDV. While much has remained the same with respect to clinical signs of disease, pathogenesis of infection including persistent infection, and diagnosis, scientific articles published since 2010 have led to a greater understanding of difficulties associated with control of BVDV. This consensus statement update on BVDV presents greater focus on topics currently relevant to the biology and control of this viral pathogen of cattle, including changes in virus subpopulations, infection in heterologous hosts, immunosuppression, and vaccination.

Noninvasive Biological Samples to Detect and Diagnose Infections due to Trypanosomatidae Parasites: A Systematic Review and Meta-Analysis

Unicellular eukaryotes of the Trypanosomatidae family include human and animal pathogens that belong to the Trypanosoma and Leishmania genera. Diagnosis of the diseases they cause requires the sampling of body fluids (e.g., blood, lymph, peritoneal fluid, cerebrospinal fluid) or organ biopsies (e.g., bone marrow, spleen), which are mostly obtained through invasive methods. Body fluids or appendages can be alternatives to these invasive biopsies but appropriateness remains poorly studied. To further address this question, we perform a systematic review on clues evidencing the presence of parasites, genetic material, antibodies, and antigens in body secretions, appendages, or the organs or proximal tissues that produce these materials. Paper selection was based on searches in PubMed, Web of Science, WorldWideScience, SciELO, Embase, and Google. The information of each selected article (n = 333) was classified into different sections and data were extracted from 77 papers. The presence of Trypanosomatidae parasites has been tracked in most of organs or proximal tissues that produce body secretions or appendages, in naturally or experimentally infected hosts. The meta-analysis highlights the paucity of studies on human African trypanosomiasis and an absence on animal trypanosomiasis. Among the collected data high heterogeneity in terms of the I2 statistic (100%) is recorded. A high positivity is recorded for antibody and genetic material detection in urine of patients and dogs suffering leishmaniasis, and of antigens for leishmaniasis and Chagas disease. Data on conjunctival swabs can be analyzed with molecular methods solely for dogs suffering canine visceral leishmaniasis. Saliva and hair/bristles showed a pretty good positivity that support their potential to be used for leishmaniasis diagnosis. In conclusion, our study pinpoints significant gaps that need to be filled in order to properly address the interest of body secretion and hair or bristles for the diagnosis of infections caused by Leishmania and by other Trypanosomatidae parasites.

Considerations for the development of a dromedary camel (Camelus dromedarius) semen collection centre

The dromedary camel (DC) is a strategic animal for the exploitation of the desert and unhospitable lands (arid and semiarid areas). These animals are a genetic resource, locally adapted and more resilient to these environs, that may significantly contribute to food security and sustainable development of marginal land areas. Artificial insemination is the least invasive, least expensive technique for improving genetic selection and minimising transmission of venereal disease among animals and herds. Besides semen preservation protocols, specific approaches for the development of DC semen collection centres - biosecurity measures, screening for infectious diseases, management of animals, welfare, nutrition, control of seasonality, training, hygiene of semen collection and processing - have been considered less important aspects. The aim of this research is to describe the aspects related to the development of a DC semen collection centre, summarising the latest studies in the field of welfare, reproduction and diseases, and describing biosecurity and hygiene aspects related to semen collection and handling. Scientific gaps and requirements for maximising the production of good quality and safe-to-use semen doses with minimal risks of disease transmission are also described.

Azoospermia in male dromedary: Clinical findings, testicular biopsy, serum follicle stimulating hormone and seminal biomarkers

Azoospermia is not an uncommon infertility problem in the male dromedary (Camelus dromedarius). Azoospermia was investigated via clinical findings, testicular biopsy as well as the evaluation of follicle stimulating hormone (FSH), concentration of camel testis protein (TEX101) and camel epididymis-specific extracellular matrix protein (ECM1) in seminal fluids. Azoospermic male camels (AZOO group, n = 28) that had been detected to be infertile as a result of lack of resulting pregnancies after repeated mating's for at least one season were included in this study. Clinical examination, semen analysis and testicular biopsy sampling were conducted for each individual animal. Blood samples were collected from the AZOO and from reference fertile males (FERT group, n = 8) for the assay of FSH hormone and semen biomarkers (TEX101 and ECM1). There were bilaterally normal-sized testes in 42.8%, bilaterally small-sized testes in 35.7%, bilaterally large-sized testes in 7.1%, no testicles in 7.1% and only one testicle in 7.1% of azoospermic animals. Sertoli cell-only syndrome (SCO) and maturation arrest were observed in 78.6% and 21.4% of the animals, respectively. There were greater concentrations of FSH in the AZOO group compared with the FERT group (P  = 0.01). In conclusion, azoospermia in dromedary camels is mainly associated with spermatogenic defects and greater serum FSH concentrations. Seminal biomarkers, therefore, might be feasible indicators for identifying azoospermia in the male dromedary camels and the condition of non-obstructive azoospermia was seemingly prevalent in the male dromedary camels in the present study.

Shortened daily photoperiod during the non-breeding season can improve the reproductive performance of camel bulls (Camelus dromedarius)

The effects of a shortened photoperiod on the reproductive performance and hormones of mature dromedary camel bulls (Camelus dromedarius) were evaluated. A group of 6 bulls were blindfolded to induce a daily photoperiod that was ∼2.55 h shorter than the natural day length (10.83L:13.17D), whereas 6 others served as the control group. The trial started in June and continued for 10 weeks during the non-breeding season. The reproductive performance of all animals was evaluated weekly during this time and also during the breeding season, starting in December and continuing for 10 weeks. Camel bulls in the treatment group showed a significant (p < 0.05) increase in testicular volume, scrotal circumference, sexual desire, reaction time, and mating ability scores, and serum melatonin and testosterone concentrations, relative to the control group, during the non-breeding season. In addition, sexual desire and reaction time and mating ability scores were significantly (p < 0.05) higher in the treatment group than in the control during the breeding season. There was no significant difference between the treatment groups in both seasons and the control group in the breeding season regarding semen volume, sperm cell concentration, total motility, progressive motility, plasma membrane integrity, and viability. Shortening the daily photoperiod by blindfolding can improve the reproductive performance of dromedary camel bulls during the non-breeding season and the following breeding season. This simple, inexpensive, and easily applicable method can enable breeders to collect semen of acceptable quality during the non-breeding season.