Atypical Myopathy: an update

Rebecca Watson MSc RVN recaps on what we know and, what we have yet to discover

Diagnostic imaging: its role in remedial shoeing

Dr. Matthew Sinovich BVSc BVSc(Hons) CertAVP(ESST) MSc MRCVS, Liphook Equine Hospital, discusses how diagnostic imaging can help vets guide farriers in treatment

The changing seasons

Briony Witherow MSc RNutr. Practical Equine Nutrition, looks at recent exceptional weather conditions and the possible impact on horses when transitioning from winter to spring

Reproductive management of the transitional mare

The mare is a seasonally polyoestrous long-day breeder with a physiological breeding season lasting from April–October in the Northern Hemisphere. The hypothalamic-pituitary-gonadal axis in the mare is subject to a circannual endogenous rhythm that is primarily regulated by day length. Increasing ambient photoperiod in the spring alters the pattern of melatonin secretion. The resulting stimulation of hypothalamic gonadotropin-releasing hormone secretion triggers pituitary follicular stimulating hormone release and follicular growth. Exposure of mares in deep anoestrus to a stimulatory photoperiod remains the most successful method of advancing the first ovulation of the season. The most commonly used lighting regimen is providing a fixed length of 15–16 hours of light exposure and 8–9 hours of dark, with a minimum light intensity in a stable of 100-lux (100–200 watt incandescent bulb). Other methods include using an additional 2.5 hours of light beginning at sunset and a pulse lighting system, providing 1 hour of light, 9.5–10.5 hours after the onset of darkness, during the photosensitive phase. Alternatively, the EquilumeTM light masks provide a unilateral LED light source emitting 50 lux of blue-light directly to the eye during the hours after dusk (until 11 pm). Mares that have not been maintained under lights, or that have been exposed to ineffective light therapy, may require therapeutic hormonal intervention to advance the onset of the first ovulation of the season. Many hormone protocols involving progestins, GnRH, dopamine agonists and recombinant luteinising hormone/follicle stimulating hormone have been studied with variable results. Therapy is typically more effective when started either in late transitional mares or following a period of stimulatory artificial photoperiod.

A pain in the back… or is it something else?

Laura Quiney IMV imaging, discusses an evidence-based approach to investigating back pain in horses – a frequently encountered yet often difficult to diagnose condition

How much does body size impact the equine foot?

Kirsty Leśniak SFHEA, PGCE, MSc, BSc (Hons) Senior Lecturer Equine Science, Hartpury University discusses a smart response to a sizeable challenge

Monitoring the early pregnancy

Monitoring of the early pregnancy is an important aspect of stud medicine practice. This article provides an overview of a common routine examination schedule adopted in the early stages of equine pregnancy, and discusses why pregnancy examination should be performed early plus at specific intervals thereafter. A description (with pictures) of the most common ultrasonographic indicators of pregnancy loss found during the examination is provided, together with some treatment options currently adopted. Because of the limitations of diagnostic ability, and incomplete understanding around early pregnancy loss, treatment options for this condition can be controversial. Finally, how to effectively diagnose and manage twins is discussed, with an understanding of how natural reduction can play its part.