Capacidade funcional em cavalos de salto suplementados com linhaça

The objective of this study was to evaluate the supplementation of linseed as an omega-3 fatty acid supplier on the functional capacity of jumping horses. 6 horses disposed in two 3 x 3 balanced Latin squares were used. The treatments consisted of increasing levels of linseed mixed with flour and linseed oil in a ratio of 75:25, respectively, resulting in 0g (control), 60g and 120g on a daily basis per horse. The horses were supplemented for 30 days. Physical activity was jumping at riding class level. The functional parameters measured were lameness index, stride length and joint metacarpophalangeal (MCP) biometry (circumference and flexion angle). A significant linseed supplementation effect for doses of 60 and 120g was observed on the lameness index. Feeding 120g of linseed increased stride length while trotting (P<0.05). An increment of 0.5cm on MCP circumference was found in horses that received the control diet when compared to those horses that consumed 120g of linseed. Thus, supplementation of jumping horses with 120g/day of linseed promoted greater stride length at a trot and reduced swelling in the metacarpophalangeal joint, improving their functional capabilities.Objetivou-se avaliar a suplementação com linhaça, como fonte do ácido graxo ômega-3, sobre a capacidade funcional de cavalos de salto. Foram utilizados seis equinos distribuídos em dois quadrados latinos 3x3 balanceados. Os grupos experimentais consistiram em níveis crescentes de linhaça (na forma de farinha e óleo de linhaça na proporção de 75:25, respectivamente), resultando nos tratamentos de 0 (controle), 60 e 120g/cavalo/dia de linhaça. Os cavalos foram suplementados por período de 30 dias. A atividade física consistiu em trabalho para salto no nível de equitação fundamental. As variáveis funcionais mensuradas foram índice de claudicação (IC), comprimento da passada e biometria da articulação metacarpofalangeana - MCF (circunferência e ângulo de flexão). Observou-se efeito significativo da suplementação com linhaça, independentemente da dosagem, sobre o IC. Ainda, o fornecimento de 120g de linhaça/cavalo/dia aumentou o comprimento da passada dos cavalos ao trote (P<0,05) e promoveu redução de 0,5cm na circunferência da articulação MCF (P<0,05) em comparação ao grupo controle. A suplementação de cavalos de salto com 120g/dia de linhaça promoveu maior comprimento da passada ao trote e redução de edema na articulação metacarpofalangeana, melhorando suas capacidades funcionais.UnespUnes

Parâmetros sanguíneos de cavalos alimentados com concentrados lipídicos submetidos a treinos aeróbicos montados

Avaliou-se o fornecimento de concentrados com baixo e alto teor de óleo de soja a cavalos atletas, submetidos a duas intensidades de treinos aeróbicos montados, sobre a resposta metabólica de parâmetros bioquímicos do sangue, de importância ao desempenho esportivo. Foram utilizados quatro cavalos, em delineamento experimental quadrado latino, com tratamentos em esquema fatorial 2x2 (duas inclusões de óleo de soja e duas rotinas de treinos aeróbicos). Os tratamentos foram compostos por teores de 5 e 15% de óleo de soja nos concentrados e duas intensidades de treinos montados por 40 e 60min, classificadas como aeróbicas. As amostras de sangue foram colhidas após o último treino de 40 ou 60min, de cada período experimental. Monitorou-se, após o exercício, os parâmetros bioquímicos, triglicerídeos (TG), colesterol total (CT), glicose (GLI) e lactato (LAC). Houve redução no teor TG (P0,05) dos tratamentos sobre GLI. Concluiu-se que, para cavalos atletas em atividade aeróbica, o oferecimento de concentrado com alto teor óleo de soja deve ser associado ao treino montado de maior intensidade.The feeding diets were evaluated containing low and high levels of soybean oil for athlete horses submitted to two rider aerobic training intensities, on the metabolic response of the blood biochemical parameters (triglyceride, total cholesterol, glucose and lactate) of importance to sports performance. Four horses were used in latin square design with treatments in a 2x2 factorial arrangement (two levels of soybean oil and two aerobic training intensities rider). Treatments consisted of levels of 5 and 15% soybean oil concentrates and two aerobic training intensities, 40 and 60 minutes. Blood samples were collected after the last workout, 40 or 60 min in each experimental period. Plasmatic parameters were monitored, triglyceride (TG), total cholesterol (TC), glucose (GLU) and lactate (LAC) after exercise. There was a reduction in TG (P0.05) of treatment on GLU. It can be concluded that the offer of concentrate with high content of soybean oil, should be associated with higher intensity aerobic training for athletic equine.Universidade Estadual Paulista Departamento de ZootecniaUniversidade de Marília Faculdade de Ciências AgráriasUniversidade Estadual Paulista Faculdade de Medicina Veterinária e Zootecnia Departamento de Melhoramento e de Nutrição AnimalUniversidade Estadual Paulista Departamento de ZootecniaUniversidade Estadual Paulista Faculdade de Medicina Veterinária e Zootecnia Departamento de Melhoramento e de Nutrição Anima

Stratified analyses refine association between TLR7 rare variants and severe COVID-19

Despite extensive global research into genetic predisposition for severe COVID-19, knowledge on the role of rare host genetic variants and their relation to other risk factors remains limited. Here, 52 genes with prior etiological evidence were sequenced in 1,772 severe COVID-19 cases and 5,347 population-based controls from Spain/Italy. Rare deleterious TLR7 variants were present in 2.4% of young (<60 years) cases with no reported clinical risk factors (n = 378), compared to 0.24% of controls (odds ratio [OR] = 12.3, p = 1.27 × 10). Incorporation of the results of either functional assays or protein modeling led to a pronounced increase in effect size (OR = 46.5, p = 1.74 × 10). Association signals for the X-chromosomal gene TLR7 were also detected in the female-only subgroup, suggesting the existence of additional mechanisms beyond X-linked recessive inheritance in males. Additionally, supporting evidence was generated for a contribution to severe COVID-19 of the previously implicated genes IFNAR2, IFIH1, and TBK1. Our results refine the genetic contribution of rare TLR7 variants to severe COVID-19 and strengthen evidence for the etiological relevance of genes in the interferon signaling pathway

Comparison of two software packages for determining radiographic bone aluminium equivalent values

Radiographic photodensitometry has been used to track changes in bone mineral content in the distal limb of horses through traditional film radiographs. With increasing popularity of digital radiographs, the technique has been adapted for digital technology. The objective of this study was to validate and describe the analysis of digital radiographs and to compare traditional densitometric analysis to digital analysis. Twelve traditional and 12 digital radiographs were taken of the left third metacarpal (MCIII) of 12 horses with an aluminium stepwedge penetrometer attached to the radiographic cassette. Both medial-lateral and dorsal-palmar views were represented. The traditional and digital radiographs were each analysed using two different methods to compare results. Analysis involved determining optical density at each step of the aluminium stepwedge, plotting optical density verses mm Al, and then determining the equation of the subsequent line. The optical density of each cortice was inserted into the equation and radiographic bone aluminium equivalents (RBAE) in mm Al for each cortice was determined. Total RBAE was also examined 1 cm distal to the nutrient foramen of the MCIII. Data were analysed using Proc CORR (SAS v. 9.1) and are reported as mean ± standard deviation. Total RBAE on the dorsal-palmar view from traditional radiographs averaged 286±154 mm Al for digital analysis and 292±173 mm Al for densitometric analysis (R2=0.98). Total RBAE on medial-lateral view from the digital radiographs averaged 539±137 mm Al for digital analysis and 530±165 mm Al for densitometric analysis (R2=0.95). The results demonstrate high correlations between analyses, thereby validating that digital analysis yields similar results as densitometric analysis. Digital radiographs, with increased clarity as compared to traditional films, should allow greater ability to detect treatment differences in research trials, and monitor changes associated with training or nutrition. </jats:p

A pilot study to determine if a dietary mineral supplement can affect reactivity to stimuli by horses in training

Trainers have reported horses to be calmer and easier to train after receiving a calcium- and magnesium-rich mineral supplement derived from a calcified algae source. The purpose of this study was to test whether horses receiving this supplement were calmer than horses receiving a placebo. Fourteen 2-year-old Arabians in training were subjected to a ‘moving object reactivity test’ (MORT) and ‘handling reactivity test’ (HRT). The MORT involves quickly raising a bag suspended from the ceiling and scoring horses' reactions. The HRT involves placing horses into breeding stocks and scoring the horses’ nervousness. Horses were equipped with heart rate (HR) monitors and were scored by four observers blinded to treatment. Reactivity scores and HR were used to randomly striate the horses into two groups: a treated group (MIN) receiving 100 g of Aquacid/horse/day and a control group (CO) receiving a placebo. After supplementation for 60 days, horses were retested. Using PROC Mixed, changes from day 0 were examined. In the MORT, CO had an increase of 29 bpm (P=0.001), while MIN only showed a trend to increase (12 bpm; P=0.1). There was no difference between treatments (P=0.12). Reactivity scores during the MORT were not different between treatments (P=0.14) with CO horses increasing by 0.58 (1 to 5 scale) and MIN horses by 0.31. In the HRT, the peak HR of CO increased from day 0 by 17 bpm (P=0.009), but only by 11 bpm in the MIN (P=0.08). Reactivity scores for MIN horses improved by 0.45 (scale from 1 to 4) while the CO worsened by 0.04. Neither HRT measurement was significant (P=0.41 and P=0.33, respectively). Limited treatment differences suggest greater subject numbers were needed due to variability in behavioural responses despite some outcomes favouring MIN. Though inconclusive, results suggest anecdotal claims of calming effects may warrant further investigation. </jats:p

Eml5, a novel WD40 domain protein expressed in rat brain

We have isolated a novel transcript with homology to the major microtubule-associated protein in dividing sea urchin embryos, EMAP. The protein has a predicted MW of similar to 180 kDa and we have named it Eml5 (EMAP-like protein 5, GenBank accession no. AY445136). Eml5 contains 11 putative WD40 domains and 3 hydrophobic stretches of 43 aa, HELP domains, which have been suggested to be involved in microtubule binding. Eml5 appears to consist of two tandem repeats of the complete EMAP protein separated by a putative dimerization domain. Eml5 mRNA and protein is expressed at high levels in the hippocampus, cerebellum and olfactory bulb, as determined by in situ hybridization and immunocytochemistry. Eml5 transcripts can be detected in fore- and hindbrain structures from embryonic day 13 onwards. Because other EMAP-like proteins are involved in regulating microtubule dynamics, it is likely that Eml5 plays a role in the regulation of cytoskeletal rearrangements during neuronal development and in adult brain.Abbreviations: EMAP, echinoderm microtubule-associated protein; EML, EMAP-like protein; MAP, microtubule-associated protein; HELP domain, hydrophobic EMAP-like protein domain; LTP, long-term potentiation; PSD, post-synaptic density

Prevalence of gastric ulcers and relationship to other parameters in Standardbred racehorses

Gastric ulcer prevalence rate is reported to be 60-90% in racehorses. This study examined a population of 40 Standardbred horses in race training and assessed the relationship of ulcers to performance history and body condition score (BCS). Forty Standardbreds on two racing facilities in southern Michigan were examined during the last 2 weeks of December 2007 and the second week of January 2008. Age of horses (as of January 1) ranged from 3 to 12 years. Squamous epithelial ulcers were graded (0-4) using an established scoring system during gastroscopic examinations and BCS was recorded (1 to 9 scale). Trainers graded racing performance of each horse on a scale of A to F, with A being best. Horses were grouped according to gender, age, and BCS. Prevalence of ulcers was similar between facilities (50% and 56%) but the mean prevalence (52.5%) was lower than in previous reports. Ulcer score was not related to gender (P=0.84), age (P=0.72), BCS (P=0.64), or performance history (P=0.55). These findings suggest that commonly cited prevalence rates of ulcers may not be consistent for all populations of racehorses. Further, given that less than 20% of the horses examined had an ulcer score grade 2 or higher, the impact that ulcers have on performance may be overestimated in some equine populations. Finally, this study clearly demonstrates that a gastroscopic examination is necessary to determine presence of ulcers, rather than assuming their presence based on decreased performance or low body condition score. </jats:p

Hydration status of horses performing endurance exercise: II. Evidence for a role of dietary fibre type, not oil supplementation

The equine large intestine has been suggested to serve as a water reservoir during prolonged exercise and may be influenced by dietary fibre source or length. At the same time, oil supplementation may result in performance and possibly hydration advantages. This study was designed to examine the effect of different fibre-based feeds, of similar particle size, on hydration status, with and without oil supplementation. Six two-year-old Arabian horses were randomly assigned to diets containing either chopped grass hay (G) or a 50:50 chopped grass hay: fibre-based chopped mix (GC) and either oil supplementation (approximately 5.7% crude fat in total diet) or no oil supplementation. Horses consumed each diet at least 21 d before completing a 60 km exercise test. Total body water, determined using deuterium oxide (D2O), was 66.1% of body mass and did not differ due to treatment. Horses consuming GC had greater (P&lt;0.05) body mass at the start of exercise than those consuming G. Water consumption during the exercise test was greater in G than GC (P&lt;0.01; 13.3±1.3 l, 10.9±1.3 l), as were packed cell volume (P&lt;0.01; G 36.8±1.2%, GC 35.1±1.2%) and plasma aldosterone across all times (P&lt;0.001; GC 0.79±0.11 pmol/l, G 1.48±0.11 pmol/l). The results suggest dietary fibre source may play a greater role in hydration status over 60 km distances than does oil supplementation. Core temperatures reported in this study were all similar to those reported in a previous study using a 50:50 long hay to chopped highly digestible fibre mix and lower than reported in previous studies using long stemmed hay or pasture suggesting the particle size or length of the fibre may have an influence and thus merit further investigation. </jats:p

Hydration status of horses performing endurance exercise: I. Evidence for a role of diet

Water and electrolyte loss from endurance exercise results in physiological disturbances in the horse. The large intestine may serve as a water reservoir and help attenuate dehydration. Dietary constituents may affect the amount of water within the intestine and available for use. This study examined the hydration status of horses fed three common diets for 14 d then subjected to a 60 km exercise test. After an initial training period, horses were assigned to a replicated 3×3 Latin Square. Diets were grass hay (G), 50:50 grass hay:alfalfa hay (GA), and 50:50 grass hay:short-chopped, fibre-based, oil-supplemented mixed feed (GM). Total body water (TBW) tended to be higher (P&lt;0.08) in horses consuming GA and GM than G (65.8±0.8, 65.4±0.8, and 63.9±0.8%, respectively). Body mass (BM) was not different at the start of the exercise test, but when corrected for faecal loss and water intake showed a trend for diet difference during exercise (P&lt;0.08), decreasing more in GM than G (5.1±0.4% vs. 3.4±0.4%; GA 4.2±0.4%). Heart rate was not different except at the end of bout one (after 15 km) when GM was lower than G or GA (P&lt;0.01). Core body temperature, although not different at the start of the exercise test bout, was lower (P&lt;0.05) at the canter in GM. As the GM diet was higher in oil, the increase in oil intake may have been responsible for the differences observed. However, more likely, the higher TBW with the GM and GA diets at the initiation of exercise, associated with more readily fermentable fibre components, may have provided a greater ‘pool’ of available water for increased thermoregulation via sweating, allowing maintenance of a lower core body temperature during exercise at the expense of increased BM loss. </jats:p