The Journal of nutrition.
Publisher:
C. C. Thomas. [New York, NY] : Elsevier (2023)
Frequency: Monthly, 1934-
Country: United States
Language: English
Author(s):
American Institute of Nutrition., Wistar Institute of Anatomy and Biology., American Society for Nutritional Sciences., American Society for Nutrition.
Start Year:1928 -
ISSN:
0022-3166 (Print)
1541-6100 (Electronic)
0022-3166 (Linking)
1541-6100 (Electronic)
0022-3166 (Linking)
Impact Factor
4.2
2022
| NLM ID: | 0404243 |
| (OCoLC): | 01782301 |
| (DNLM): | J32220000(s) |
| Coden: | JONUAI |
| LCCN: | 33014482 |
| Classification: | W1 JO798 |
Amino acid supplementation does not alter whole-body phenylalanine kinetics in Arabian geldings. Stable isotope infusion methods have not been extensively used in horses to study protein metabolism. The objectives were to develop infusion and sampling methodologies for [1-(13)C] phenylalanine and apply these methods to determine whether the addition of supplemental amino acids to a control diet affected whole-body phenylalanine kinetics in mature horses. Arabian geldings were studied using a 6-h primed (9 μmol/kg), constant (6 μmol · kg(-1) · h(-1)) i.v. infusion of L-[1-(13)C] phenylalanine, with blood and breath sampled every 30 min, to measure whole-body phenylalanine kinet...
Dietary energy source affects glucose kinetics in trained Arabian geldings at rest and during endurance exercise. Advances in modeling and tracer techniques provide new perspective into glucose utilization and potential consequences to health or exercise performance. This study used stable isotope and compartmental modeling to evaluate how adaptation to a feed high in sugar and starch (SS) compared with a feed high in fat and fiber (FF) affects glucose kinetics at rest and during exercise in horses. Six trained Arabians adapted to each feed underwent similar tests at rest and while running approximately 4 m/s on a treadmill. For both tests, horses received 100 micromol/kg body weight [6,6-(2)H]glucose thr...
Nutritional consequences of interspecies differences in arginine and lysine metabolism. Differences in lysine and arginine requirements among various species such as omnivores (humans, pigs, rats, dogs), carnivores (cats), herbivores (rabbits, horses), ruminants (cattle), poultry, and fish, are covered in detail in this article. Although lysine is classified as an indispensable amino acid across species, the classification of arginine as either an indispensable or dispensable amino acid is more ambiguous because of differences among species in rates of de novo arginine synthesis. Because lysine is most often the limiting amino acid in the diet, its requirement has been extensivel...
10.1093/jn/136.7.2090S. Treatment of clinical laminitis usually fails to prevent some degree of persistent disability; thus, intervention should aim at avoiding risk factors and preventing the disease. Efficiency of intervention would be improved by identifying predisposed horses and ponies. A herd of 160 healthy ponies included 54 previously laminitic (PL) and 106 never laminitic (NL). Pedigree analysis was consistent with dominant inheritance partially suppressed in males. Blood analysis revealed higher plasma concentrations of insulin and triglycerides but not cortisol, glucose, or free fatty acids in the PL group...
Pasture nonstructural carbohydrates and equine laminitis. Fresh forages constitute a majority of the diet for many horses and ponies that graze on pastures during the growing season in many parts of the world. Grasses generally predominate in such pastures, with varying proportions of legumes. Nonstructural carbohydrates (NSC) (simple sugars, starch, and fructan) can induce laminitis experimentally, and NSC can accumulate to >400 g/kg of dry matter (DM) in pasture grasses. In this article we discuss the environmental factors affecting NSC accumulation in pastures and estimate the potential daily intakes of pasture NSC by grazing horses. We also di...
Insulin resistance in equids: possible role in laminitis. Insulin is a major regulatory hormone in glucose and fat metabolism, vascular function, inflammation, tissue remodeling, and the somatotropic axis of growth. Insulin resistance alters insulin signaling by decreasing insulin action in certain resistant pathways while increasing insulin signaling in other unaffected pathways via compensatory hyperinsulinemia. In humans, altered insulin signaling is implicated in reduced glucose availability to insulin-sensitive cells, vasoconstriction and endothelial damage, and inflammatory response. Although no direct evidence exists for insulin's role in thes...
Countermeasures for pasture-associated laminitis in ponies and horses. Laminitis occurs throughout the world in horses and ponies and has major welfare implications. It is obviously important to be able to recognize and treat the condition in its early stages so that pain and suffering are kept to a minimum. However, ideally it would be preferred to be able to recommend certain interventions/countermeasures that avoid or prevent the condition from occurring in the first place. Because pasture-associated laminitis occurs with grass consumption, one obvious way to avoid the condition is to prevent access to pasture and to feed forage alternatives that are known to ...
Gastrointestinal derived factors are potential triggers for the development of acute equine laminitis. Equine laminitis is the painful and debilitating condition resulting from cellular damage and inflammation of the tissues comprising the bonds supporting the pedal bone within the hoof capsule. One of the reasons why this condition is so complicated and enigmatic is its association with gastrointestinal disturbances, particularly a diet of lush grass at certain times of the year. Determining the link between disturbances to the hindgut flora and pathophysiology in the foot is one of the keys to preventing this condition. Therefore, one of the biggest challenges in equine laminitis research is ...
Application of the comet assay for investigation of oxidative DNA damage in equine peripheral blood mononuclear cells. Oxidative stress occurs when antioxidant defense mechanisms are overwhelmed by free radicals and may lead to DNA damage, which has been implicated in processes such as aging and diseases such as cancer. The two main techniques presently used to quantify DNA damage are measurement of 8-hydroxydeoxyguanosine and the Comet assay (also known as single-cell gel electrophoresis). The aim of this study was to apply the comet assay to equine peripheral blood mononuclear cells (PBMCs) and identify two conditions in which we hypothesized that oxidative DNA damage would be increased in PBMCs: aging and e...
Lipoic acid as an antioxidant in mature thoroughbred geldings: a preliminary study. alpha-Lipoic acid (LA) has demonstrated antioxidant effects in humans and laboratory animals. The objective of this study was to determine whether the effects of LA are similar in horses. Five Thoroughbred geldings were supplemented with 10 mg/kg/d DL-alpha-lipoic acid in a molasses and sweet feed carrier and five received only the carrier as a placebo (CON). Blood samples were obtained at baseline (0 d), after 7 and 14 d of supplementation, and 48 h postsupplementation (16 d). Blood fractions of red and white blood cells (RBC and WBC, respectively) and plasma were analyzed for glutathione (GS...
Changes in circulatory antioxidant status in horses during prolonged exercise. Prolonged low-medium intensity exercise is associated with increased oxidative stress in humans. We hypothesized that competitive equine endurance racing would induce changes in circulatory antioxidants and produce systemic oxidative stress. Forty horses competing in a 140-km endurance race in warm conditions [shade temperature 15-19 degrees C; 62-88% relative humidity (%RH)] were sampled before (Pre), immediately after exercise (End) and at approximately 16 h into recovery (+16 h). Plasma ascorbic acid concentration was not different between Pre [11.1 (median); 4.6-20.3 micromol/L (range)] an...
Dietary protein restriction and fat supplementation diminish the acidogenic effect of exercise during repeated sprints in horses. A restricted protein diet supplemented with amino acids and fat may reduce the acidogenic effects of exercise. Twelve Arabian horses were assigned to a 2 x 2 factorial experiment: two fat levels: 0 or 10 g/100 g added corn oil and two crude protein levels: 7.5 g/100 g (supplemented with 0.5% L-lysine and 0.3% L-threonine) or 14.5 g/100 g. The experiment began with a 4-wk diet accommodation period followed by a standard exercise test consisting of six 1-minute sprints at 7 m/s. Horses were interval trained for 11 wk followed by another exercise test with sprints at 10 m/s. Blood samples were ta...
Carbohydrate supplementation of horses during endurance exercise: comparison of fructose and glucose. To delay the onset of fatigue, endurance horses are often fed at rest stops during races. The resulting increase in blood insulin may adversely inhibit lipolysis. In humans, ingestion of fructose produces a smaller insulin rise than glucose. This study compared glucose and fructose as carbohydrate supplements for endurance horses. Three Arabian geldings were given 300 g of fructose (F), glucose (G) or 50% glucose: 50% fructose (GF), in 1.5 L water, by stomach tube. In the Resting Test, carbohydrate was administered at rest. Following treatment, blood samples were taken every 30 min for 8 h, an...
Exercise affects digestibility and rate of passage of all-forage and mixed diets in thoroughbred horses. Most digestibility studies in horses have been conducted with idle horses confined to metabolism stalls. The values obtained from such studies are used for all classes of horses, including the performance horse. It has not been clearly established whether exercise affects digestibility. Olsson and Ruudvere (1955), summarizing a number of earlier studies, suggested that digestion may be affected in horses by work or exercise in such a way that it is improved by light exercise and inhibited by heavy work.
Orton et al. (1985) reported reduced retention time of a particulate marker in yearling ...
Developments in equine nutrition: comparing the beginning and end of this century. In the first part of this century, there was little advancement in horse nutrition and little research was undertaken. However, in the last few years, there has been a great increase in interest in this whole area. This review surveys some of the more recent developments and how they have influenced feeding practices and also compares these with those feeding practices found at the start of this century. The review concentrates on the nutrition of the adult horse in work, exploring in particular what they are fed and how the nutrient value of these feeds is evaluated.
Importance of sphingolipids and inhibitors of sphingolipid metabolism as components of animal diets. Sphingolipids are highly bioactive compounds that participate in the regulation of cell growth, differentiation, diverse cell functions, and apoptosis. They are present in both plant and animal foods in appreciable amounts, but little is known about their nutritional significance. Recent studies have shown that feeding sphingomyelin to female CF1 mice treated with a colon carcinogen (1,2-dimethylhydrazine) reduced the number of aberrant colonic crypt foci; longer-term feeding also affected the appearance of colonic adenocarcinomas. Therefore, dietary sphingolipids should be considered in studi...