An Update on Semen Physiology, Technologies, and Selection Techniques for the Advancement of In Vitro Equine Embryo Production: Section II

As the use of assisted reproductive technologies (ART) and in vitro embryo production (IVP) expand in the equine industry, it has become necessary to further our understanding of available semen selection techniques. This segment of our two-section review will focus on the selection of spermatozoa based on quality and sex for equine intracytoplasmic sperm injection (ICSI), as well as current and future developments in sperm sorting technologies. Ultimately, novel methods of semen selection will be assessed based on their efficacy in other species and their relevance and future application towards ARTs in the horse.

An Update on Semen Physiology, Technologies, and Selection Techniques for the Advancement of In Vitro Equine Embryo Production: Section I

As the use of assisted reproductive technologies (ART) and in vitro embryo production (IVP) expand in the equine industry, it has become necessary to further our understanding of semen physiology as it applies to overall fertility. This segment of our two-section review will focus on normal sperm parameters, beginning with development and extending through the basic morphology of mature spermatozoa, as well as common issues with male factor infertility in IVP. Ultimately, the relevance of sperm parameters to overall male factor fertility in equine IVP will be assessed.

Undergraduate Certificate in Equine Science and Management

Iowa State University offers undergraduate certificates to demonstrate completion of a focused study in a specialized area. The certificate has the significant benefit of allowing students to customize their curriculum and document an approved course of study. An Equine Science and  Management Certificate is offered within the Animal Science Department at Iowa State University. The certificate requirements are organized to correspond with faculty and employer-defined needs for a successful transition from student to equine industry professional.  The Equine Science and  Management certificate will integrate technical topics in animal science with practical considerations in enterprise management. Two critical components to the certificate are the capstone Equine Systems Management course and a required internship in equine science and management. Students that complete the certificate will have the background to identify and address challenges in modern equine enterprises. Further, the certificate assists employers in identifying students that have shown the interest, discipline, and ability to complete this specialized study program. 

Characterization of indoor arenas through an anonymous survey

Equine farms are building both stables for the horses to live in and additional facilities to train and work horses . For many of these farms, an outdoor arena that has an all-weather footing is the first working facility built. During inclement weather the ability to train in the outdoor arenas is inhibited, which in turn means the trainers, riders, and farms lose income as money is only made when horses are working, training, and competing. Indoor arenas allow for horses to continue to be worked no matter the weather conditions. The equine industry contributes a total of $122 billion dollars a year to the United States’ economy. The expenditures to build and maintain these arenas the horses utilize for training and work are a portion of the equine economic contribution . During the summer of 2018, an anonymous online survey was conducted to begin to characterize indoor arenas. Owners, managers, and riders were questioned on a variety of topics including arena construction and design, arena usage, footing type, maintenance practices, environmental concerns, and potential health issues experienced within the facilities. Respondents in the study defined indoor arenas differently depending on geographic region, however most definitions included a roof, some enclosure, and footing in order to work the horses. In addition, of the 335 respondents of the survey, 71% or 239 respondents reported having concerns about the environment within the indoor arena. The three main concerns are dust, moisture, and lack of air movement. Overall, the survey begins to build our understanding regarding these facilities and provides the framework to continue research in the future.

The Effect of Human–Horse Interactions on Equine Behaviour, Physiology, and Welfare: A Scoping Review

Human–horse interactions (HHIs) are diverse and prominent in the equine industry. Stakeholders have an invested interest in making sure that HHIs are humane. Assessment of equine welfare goes beyond physical health and includes assessment of the emotional state of the animal. HHIs can have a permanent effect on human–horse relationships, thereby influencing welfare. Therefore, an understanding of the horse’s affective state during HHIs is necessary. A scoping review was conducted to: (1) map current practices related to the measurement of HHIs; (2) explore the known effects of HHIs on horse behaviour and physiology; and (3) clarify the connection between HHIs and equine welfare. A total of 45 articles were included in this review. Studies that used both physiological and behavioural measures of equine response to human interactions accounted for 42% of the included studies. A further 31% exclusively used physiological measures and 27% used behavioural observation. Current evidence of equine welfare during HHIs is minimal and largely based on the absence of a negative affective state during imposed interactions. Broadening the scope of methods to evaluate a positive affective state and standardization of methodology to assess these states would improve the overall understanding of the horse’s welfare during HHIs.

Equine Coital Exanthema: New Insights on the Knowledge and Leading Perspectives for Treatment and Prevention

Equine coital exanthema (ECE) is a highly contagious, venereally-transmitted mucocutaneous disease, characterized by the formation of papules, vesicles, pustules and ulcers on the external genital organs of mares and stallions, and caused by equid alphaherpesvirus 3 (EHV-3). The infection is endemic worldwide and the virus is transmitted mainly through direct contact during sexual intercourse and by contaminated instruments during reproductive maneuvers in breeding facilities. The disease does not result in systemic illness, infertility or abortion, yet it does have a negative impact on the equine industry as it forces the temporary withdrawal of affected animals with the consequent disruption of mating activities in breeding facilities. The purpose of this review is to provide up-to-date relevant information on the knowledge of EHV-3 infection and to analyze new approaches on diagnostics, treatment and prevention in the interest of minimizing the negative consequences of ECE in light of the current situation of the equine industry.

Identification of a Ruminant Origin Group B Rotavirus Associated with Diarrhea Outbreaks in Foals

Equine rotavirus group A (ERVA) is one of the most common causes of foal diarrhea. Starting in February 2021, there was an increase in the frequency of severe watery to hemorrhagic diarrhea cases in neonatal foals in Central Kentucky. Diagnostic investigation of fecal samples failed to detect evidence of diarrhea-causing pathogens including ERVA. Based on Illumina-based metagenomic sequencing, we identified a novel equine rotavirus group B (ERVB) in fecal specimens from the affected foals in the absence of any other known enteric pathogens. Interestingly, the protein sequence of all 11 segments had greater than 96% identity with group B rotaviruses previously found in ruminants. Furthermore, phylogenetic analysis demonstrated clustering of the ERVB with group B rotaviruses of caprine and bovine strains from the USA. Subsequent analysis of 33 foal diarrheic samples by RT-qPCR identified 23 rotavirus B-positive cases (69.69%). These observations suggest that the ERVB originated from ruminants and was associated with outbreaks of neonatal foal diarrhea in the 2021 foaling season in Kentucky. Emergence of the ruminant-like group B rotavirus in foals clearly warrants further investigation due to the significant impact of the disease in neonatal foals and its economic impact on the equine industry.

Applying the science of behaviour change to the management of strangles

The Strangles Symposium in 2019 gathered equine stakeholders from across the industry to discuss the management and prevention of strangles in the UK. The understanding of Streptococcus equi is increasing as is the ability to identify and treat the disease. There is real potential to reduce the incidence of the disease, as highlighted through the guidance produced by experts in 2021. It has been recognised that the preventative measures identified require the behaviour of people across the equine industry to alter. The science of human behaviour change can support the veterinary profession in applying effective, evidence-based interventions to optimise the success of these changes. Pinpointing what behaviours are or are not being performed, and researching what is motivating these behaviours, is key to forming strategies within veterinary practice and at UK policy level, to ensure a targeted and consistent approach is available for people within the equine sector.