Serum total and bone alkaline phosphatase levels and their correlation with serum minerals over the lifespan of sheep

This study aimed to assess serum total alkaline phosphatase (ALP) and its bone isoform (BALP) levels during the ageing and in different physiologic states of sheep, in order to expand the knowledge about the variation of these biomarkers over the sheep lifespan. Ninety female sheep were divided into nine groups of various ages and physiological states (dry, lactation and pregnancy). Serum ALP, BALP and mineral levels were determined by commercial immunoassay, molecular absorbance spectrophotometry and chemical luminescence for BALP determination. Serum ALP and BALP decreased as sheep aged, and no statistically significant differences were obtained between ewes in different physiologic states. The continuous decline of serum BALP concentration along the sheep lifespan, namely in mature and old sheep, is a sign of decreasing bone turnover associated with ageing. Serum calcium concentrations increased slightly until 2 years of age and then showed a tenuous but statistically significant decrease in mature sheep, while serum phosphorus maintained an uninterrupted decrease as sheep matured. The knowledge of serum values of bone biomarkers throughout the sheep lifespan may be useful in preclinical orthopaedic research studies and for animal science studies using sheep.Cristina P. Sousa acknowledges the Portuguese Foundation for Science and Technology for her PhD scholarship SFRH/BD/45018/2008

Bone turnover markers in sheep and goat: a review of the scientific literature

Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.José Arthur de A. Camassa acknowledges to the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil, for his PhD scholarship 202248/2015-1.info:eu-repo/semantics/publishedVersio

A glycogen synthase 1 mutation associated with equine polysaccharide storage myopathy and exertional rhabdomyolysis occurs in a variety of UK breeds

REASONS FOR PERFORMING STUDY A glycogen synthase (GYS1) mutation has been described in horses with histopathological evidence of polysaccharide storage myopathy (PSSM) in the USA. It is unknown whether the same mutation is present in horses from the UK. OBJECTIVES To determine whether the GYS1 mutation occurs in UK horses with histopathological evidence of PSSM and exertional rhabdomyolysis. HYPOTHESIS The R309H GYS1 mutation is present in a variety of UK horse breeds and that the mutation is commonly associated with exertional rhabdomyolysis. METHODS DNA was extracted from 47 muscle or blood samples from UK horses with histories of exertional rhabdomyolysis in which muscle biopsy diagnosis had been pursued. The proportions of GYS1 mutation positive cases were compared among histopathologically defined groups. In addition, breeds that carried the GYS1 mutation were identified from a total of 37 grade 2 (amylase-resistant) PSSM cases. RESULTS Of 47 horses with exertional rhabdomyolysis in which a muscle biopsy diagnosis was pursued, 10 (21%) carried the GYS1 mutation. The mutation was only found in horses with grade 2 PSSM (i.e. not in horses with normal, idiopathic myopathy or grade 1 PSSM biopsy samples). In total, the GYS1 mutation was found in 24/37 (65%) of grade 2 PSSM cases. A variety of breeds, including Quarter Horse, Appaloosa, Warmblood, Connemara-cross, Cob, Polo Pony and Thoroughbred cross carried the mutation. CONCLUSIONS The GYS1 mutation is an important cause of exertional rhabdomyolysis of UK horse breeds but does not account for all forms of PSSM. POTENTIAL RELEVANCE Genotyping is recommended in cases of exertional rhabdomyolysis, prior to or in combination with, muscle biopsy. However a significant proportion of horses with histopathological evidence of PSSM and/or exertional rhabdomyolysis have different diseases