Nutrient intake of horses in Thoroughbred and Standardbred stables

SUMMARY Twenty-five Thoroughbred (TB) and 25 Standardbred (SB) stables were visited to determine their feeding practices. The ingredients of the main feed of the day for a mature gelding of average size in full training were weighed at each stable. Nutrient content of diets was calculated using published data for the individual ingredients. Results are expressed as mean±sd. The estimated body weight of TB horses was 493±34 kg and 437±32 kg for SB horses. There was considerable variation in diet composition and nutrient intake between stables. The TB trainers fed 11.0±2.4 kg and SB trainers 11.8±2.5 kg per day. The concentrate component of the diet weighed 7.8±1.6 and 7.7±2.3 kg for TB and SB stables, respectively, and the roughage component for TB horses 3.3±1.4 and SB horses 4.1±1.4 kg per day. The digestible energy intake of horses at TB stables was 129±29 MJ per day and at SB stables 132±31 MJ per day. Crude protein intake of TB horses was 1452±363 g and SB horses 1442±338 g per day. There were differences in some feeding practices at TB and SB stables. Standardbred trainers fed more roughage than TB trainers. Standardbred trainers fed chaffed lucerne (alfalfa) and cereal hays as the major roughage, whereas TB trainers fed more hay. The major hay type fed by TB trainers was lucerne, whereas many SB trainers preferred clover hay. Both trainers fed oats as the major grain, but TB trainers fed slightly more maize (corn) than SB trainers. The SB trainers fed barley as part of the concentrate component of the diet, whereas TB trainers usually fed boiled barley and linseed oil in winter only. Although many trainers used vitamin and mineral supplements, this appeared unnecessary in many Instances, especially with respect to Iron. Calcium and NaCI supplementation was necessary for some diets. We concluded that while there was a wide range in feed intake and diet composition for both TB and SB horses, average nutrient intakes were similar to National Research Council (1989) recommendations for horses performing intense work.     

The potential use of plasma glutamate dehydrogenase activity for the evaluation of hepatic disease in the cockatiel (Nymphicus hollandicus)

A reference interval for plasma glutamate dehydrogenase (GD) (E.C. 1.4.1.3) activity, of 0-8 IU/L, was established for the cockatiel (Nymphicus hollandicus). An automated modification of a commercial manual assay was used. This enzyme is considered liver specific in humans and numerous domestic animals, due to its organ distribution. A similar distribution was found in cockatiels in this study. Maximal enzyme activity was recovered from liver and kidney homogenate supernatants. Minimal activity was detected in skeletal muscle preparations. These results suggest a potential use for plasma GD activity in the evaluation of hepatocelluar injury/necrosis in cockatiels.     

Idiopathic eosinophilic colitis lesions of the equine small (descending) colon

Five horses with a primary surgical lesion of the small (descending) colon were diagnosed with eosinophilic colitis based on visual and histopathological examination. These were evident as visibly striking, hyperaemic, focal lesions of the small colon, with serosal petechiation, oedema and marked thickening of the intestinal wall at the site. Areas of focal necrosis were also evident. The gross appearance of the lesions were considered to be sufficiently severe in all cases to merit resection, due to concerns about intestinal necrosis and septic peritonitis. An inability to fully exteriorise the affected portion of intestine to perform a resection and anastomosis necessitated intraoperative euthanasia of one horse. A total of three horses survived to hospital discharge. Eosinophilic colitis lesions are a rare cause of severe small colon disease, but should be considered in cases with similar visual characteristics.     

Impact of sampling and storage technique,and duration of storage,on the composition of fresh grass when analysed using near‐infrared reflectance spectroscopy

The objective of this study was to examine the effect of sampling technique (pluck or cut), storage duration (immediate analysis, 24‐h or 48‐h), storage temperature (ambient or chilled) and storage conditions (air present, air excluded or breathable) on the composition of fresh grass sampled from a sward managed to simulate grazing. Treatments were repeated across four sampling dates, with grass samples stored in grip seal bags prior to analysis using near‐infrared reflectance spectroscopy. Grass sampled by ‘pluck’ had a higher crude protein and ME content, and a lower acid detergent fibre (ADF) content, compared to that sampled by ‘cut’. Grass stored for 48 h had a lower water soluble carbohydrate (WSC) and ME content and a higher ADF content than for immediate analysis. Samples stored for 24 h did not differ from immediate analysis. Grass stored at ambient temperature had a lower WSC and ME content compared to immediate analysis. Grass stored under ‘breathable’ conditions had a lower ME content and higher ADF content than immediate analysis or samples stored with air present or air excluded. It is recommended that grass for analysis should be sampled by cutting, stored chilled (4°C) in a sealed bag to minimize exposure to oxygen and analysed within 24 h of harvest.     

On the distribution of tree growth stresses

Summary A plane strain pure bending elastic model is used to predict stress states in a cylindrically orthotropic cylinder due to asymmetric strain distributions continously induced at the periphery. A general solution for the stress states related to each component of the strain distribution expanded in a Fourier series is given. Details of solutions for eleven representative tree species are given. Also the change of curvature of a stem caused by a measured peripheral strain distribution is computed for a given period of growth.     

Residual stresses caused by growth stresses within a stem with radially varying spiral grain angle – two numerical solution approaches: 1) finite element method and 2) transfer matrix method

Two numerical methods, the Finite Element (FE) method and the Transfer Matrix (TM) method, have been applied to derive a solution for residual stresses in a stem. The source of stress is the maturation strains in new wood cells, which give rise to growth stresses. The methods are generally applicable to the case of spiral grain with a grain angle varying with radius, which often is the case in trees. Also, the methods allow for the elastic constants to vary with the radius, which is important to model, for example, juvenile wood. The numerical solutions are checked against an analytical solution in the case of a constant grain angle, and are found to coincide. In addition, the two methods are shown to independently produce the same stress distribution for one pattern of grain angle variation. This shows that the methods are reliable, and they will be used for obtaining a wider range of solutions in a subsequent paper. Received: 13 January 1998