Bibliographic Synthesis of Sero-Epidemiological Studies on Brucellosis in Domestic Ruminants (Cattle, Sheep and Goats) in Cameroon

Brucellosis is a neglected zoonosis in Cameroon but it remains enzootic in some agro-ecological zones of the country. This review aims to describe the current status of this disease in domestic ruminants in Cameroon. In order to know the current status of this disease, a systematic and synthetic review was conducted on brucellosis in domestic ruminants in Cameroon. Different types of studies with serological results were reported and considered. A total of 16 studies from 1980 to 2020 were included in this synthetic review of the literature. Most of the studies were cross-sectional descriptive studies (p = 0.12). However, there were also studies with simplified survey methods, modelling approaches, stratified non-probabilistic and probabilistic surveys. 5095 cases of brucellosis infection were identified in the literature, for which the laboratory diagnosis allowed confirmation of brucellosis in the different species (indirect or direct Elisa in the majority of studies (41%), followed by rose Bengal (26%)). In most cases cattle represent 80% of the most studied species. Associated with this, the northern part of Cameroon was the preferred study area at 70% followed by the west (27%) and the south (3%). The biological material of choice for the studies was serum (75%). In addition, other biological materials (15%) were used. This systematic review has identified the tools used over the last 40 years to diagnose brucella infection in ruminants in Cameroon. However, it highlights the need for continuous monitoring of the spatio-temporal evolution of abortive microorganisms on farms.

Nutritional Quality of Opuntia ssp. at Different Phenological Stages: Implications for Forage Purposes

The study aimed to evaluat the chemical composition of forage cactus cladodes of the genus Opuntia spp. at different stages of phenological development. The experiment was conducted in a completely randomized design, with a 4×3 factorial scheme, with four species of cactus (Opuntia stricta Haw, Opuntia undulata Griffiths, Opuntia atropes Rose and Opuntia larreri FAC Weber) and three stages of cladode development (young, intermediate, and mature). The chemical composition of Opuntia cladodes varied according to species and phenological stage. Dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) concentrations increased, and crude protein (CP) decreased with cladode maturation. The species O. atropes had the lowest levels of organic matter (OM), CP, total carbohydrates, and non-fibrous carbohydrates, as well as the highest values of mineral matter, NDF and ADF. Calcium and phosphorus contents increased with cladodium maturation. The concentrations of boron, copper and manganese were higher in the young and intermediate stages. The cladodes of O. stricta, O. undulata and O. larreri showed better nutritional quality for feeding domestic ruminants. Young and intermediate cladodes are more proteinaceous and less fibrous. These results can be useful in selecting the forage cactus species and in optimizing the use of cladodes for feeding different categories of ruminants in semiarid regions.

The first report of the seroprevalence of antibodies against Bartonella spp. in water buffaloes (Bubalus bubalis) from South Thailand

Background and Aim: Bartonellosis is an emerging worldwide zoonosis caused by bacteria belonging to the genus Bartonella. Several studies have been conducted on the prevalence of Bartonella infections from animals and humans, including reports from wild and domestic ruminants. However, there has been only one report of Bartonella infection in water buffaloes from the northeastern part of Thailand. Moreover, the seroprevalence of Bartonella spp. in water buffaloes still remains unknown. This study was conducted to explore the prevalence of Bartonella spp. among water buffaloes from South Thailand using molecular and serological techniques. Materials and Methods: A total of 312 samples (156 blood and 156 sera) of 156 water buffaloes from 29 farms in Phatthalung Province, South Thailand, were collected from January to March 2021. All samples were screened for Bartonella spp. using polymerase chain reaction and indirect immunofluorescence assay. Results: The seroprevalence of antibodies against three Bartonella spp. was 16.03% (25/156, 95% confidence interval: 10.65-22.74%), and among 25 water buffaloes with seroprevalence, 56%, 20%, and 24% were positive for antibodies against Bartonella henselae, Bartonella vinsonii subspp. berkhoffii, and Bartonella tamiae, respectively. No significant difference was detected among seroprevalence, gender, age, and ectoparasite infestation. Conclusion: This is the first report of the seroprevalence of antibodies against B. henselae, B. vinsonii subspp. berkhoffii, and B. tamiae in water buffaloes from South Thailand. Further studies are required on the epidemiology of Bartonella infection among water buffaloes, related personnel, and ectoparasites.

Severe pulmonary fascioloidosis in a wild Mouflon (Ovis musimon) - a case report

Summary A wild male mouflon (Ovis musimon) was shot due to the observed weakness. Necropsy revealed consolidated lungs and traces of black pigment and fibrin on the liver. On the cut surface, a juvenile fl uke was found in the lungs, while traces of destroyed fl ukes’ migratory channels were found in the liver. F. magna infection in both, wild and domestic ruminants, causes three types of species-specific host-parasite interactions; definitive, dead-end and aberrant. mouflon are classifi ed as aberrant hosts and here we report unsuccessful migration of a juvenile fl uke that led to a severe pneumonia.

Effect of Paratuberculosis Vaccination on the in Vitro Release of Neutrophil Extracellular Traps in a Sheep Model

Background Vaccination of domestic ruminants against paratuberculosis has shown beneficial results in the control of the disease, even though protection is incomplete. This is partly due to the unawareness about the mechanisms taking part during protective immune response. In this sense, despite of the increased number of evidences that point out the participation of neutrophils in the homologous and heterologous protection, its key role is still unclear. Therefore, we evaluate the effect of paratuberculosis vaccination on the release of neutrophil extracellular traps (NETs), through its quantification and visualization after their in vitro infection with Mycobacterium avium subsp. paratuberculosis (Map) and non-related pathogens in a sheep model. Methods Ovine neutrophils were obtained from non-vaccinated (n = 5) and vaccinated sheep (n = 5) and infected in vitro with Map, Staphylococcus aureus (SA) and Escherichia coli (EC). After 4 hours, NETs release was quantified and visualized by fluorimetry and immunofluorescence microscopy, respectively. Results NETs components were confirmed by co-localization of extracellular DNA with neutrophil elastase and myeloperoxidase visualized by immunofluorescence. Infection of ovine neutrophils with Map (P > 0.05), SA (P < 0.001) and EC (P < 0.01) induced the formation of NETs before vaccination as well as after 15- and 30-days post-vaccination. However, neither vaccination nor time post-vaccination did modify the generation of NETs. Conclusions These results show that the release of NETs did not play a fundamental role in the early homologous and heterologous protective immune response after paratuberculosis vaccination, although, other antimicrobial mechanisms not evaluated in this study may participate in the protective immune response.

Perspectives on the Changing Landscape of Epizootic Hemorrhagic Disease Virus Control

Epizootic hemorrhagic disease (EHD) is an insect-transmitted viral disease of wild and domestic ruminants. It was first described following a 1955 epizootic in North American white-tailed deer (Odocoileus virginianus), a species which is highly susceptible to the causative agent of EHD, epizootic hemorrhagic disease virus (EHDV). EHDV has been detected globally across tropical and temperate regions, largely corresponding to the presence of Culicoides spp. biting midges which transmit the virus between ruminant hosts. It regularly causes high morbidity and mortality in wild and captive deer populations in endemic areas during epizootics. Although cattle historically have been less susceptible to EHDV, reports of clinical disease in cattle have increased in the past two decades. There is a pressing need to identify new methods to prevent and mitigate outbreaks and reduce the considerable impacts of EHDV on livestock and wildlife. This review discusses recent research advancements towards the control of EHDV, including the development of new investigative tools and progress in basic and applied research focused on virus detection, disease mitigation, and vector control. The potential impacts and implications of these advancements on EHD management are also discussed.

Occurrence of malformed calves in April - May 2021 indicates an unnoticed 2020 emergence of Schmallenberg virus in Denmark

During the European emergence of Schmallenberg virus (SBV) in 2011, examination of Culicoides spp. showed that SBV infected midges were present across Denmark. However, SBV associated malformations in ruminant species have not been reported in Denmark. In April 2021, seven calves with severe congenital generalized arthrogryposis and reduced body weight originating from a narrow region of the Jutlandic peninsula were submitted for examination. Analysis of fetal brain tissue for SBV viral RNA and pleural effusion for fetal anti-SBV antibodies identified SBV as the cause of the congenital syndrome. Backwards calculation from the calving dates indicated the occurrence of an unnoticed emergence of SBV in Denmark from early August 2020 and during the late summer and autumn. As SBV associated malformations may lead to dystocia urging for fetotomy or Cesarean section, veterinarians performing obstetric intervention are first line personnel in recognition of SBV emergence in domestic ruminants.

Artificial Reproductive Technology (ART) Applied to Female Cervids Adapted from Domestic Ruminants

There are about 150 Cervidae species on the IUCN Red List of Threatened Species. Only a small part is counted among farm animals, and most of them are free roaming. The universality and large numbers of representatives of cervids such as red deer (Cervus elaphus) and roe deer (Capreolus capreolus) may predispose these species to be used as models for research on reintroduction or assisted reproduction of deer at risk of extinction. We outlined the historical fluctuation of cervids in Europe and the process of domestication, which led to breeding management. Consequently, the reproductive techniques used in domestic ruminants were adapted for use in female deer which we reviewed based on our results and other available results. We focused on stress susceptibility in cervids depending on habitat and antropopression and proposed copeptin as a novel diagnostic parameter suitable for stress determination. Some reproductive biotechniques have been adopted for female cervids with satisfactory results, e.g., in vitro fertilization, while others still require methodological refinement, e.g., cryopreservation of oocytes and embryos.

258 W112 Reproductive Performance in Domestic Ruminants: 50 Years of accomplishment: a USDA-NIFA Multistate Research Project

This symposium acknowledges the founders of W112 Reproductive Performance in Domestic Ruminants. The contributions they made laid foundation collaborative efforts that continued over the next half century. The W112 really began in 1969 as a rewritten project involving several Agricultural Experiment Stations. That original project was W-49, that had been in existence at least as early as 1958. Upon approval of the project renewal in early 1970, the project was renamed W112 Reproductive Performance in Domestic Ruminants. The list of names of participants is like a who’s who of reproductive physiologists, too long to enumerate here. Increasing knowledge of physiology and endocrinology were paramount during the early years. Development, improvement, and sharing of analytical techniques improved accuracy of results, safety of procedures, and knowledge to be gained from the research. Concurrently, mechanistic basic and applied studies involving oocyte development, ovulation, sperm development, fertilization, pregnancy, and parturition all brought new understanding of the reproductive biology of domestic species. A good deal of what we currently know of the reproductive biology of ruminant animals finds some basis in laboratories involved in W112 collaborations. The unique nature of these scientists resulted from their mutual respect. Many young scientists found mentors in W112 that assisted us in developing our own research programs. And the support has not ended with research collaboration. It has been common for project participants to share teaching resources and serve on graduate student committees for each other’s students, fostering future involvement in the project. The W112 began slightly more than 50 years ago. Those of us who have been part of this group share a hope that the multistate project named Reproductive Performance in Domestic Ruminants will still be meeting the same goals of collaboration and support among scientists working to further animal agriculture for another 50 years and more.