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21.

Background

The branched chain amino acid leucine is a potent stimulator of insulin secretion. Used in combination with glucose it can increase the insulin response and the post exercise re-synthesis of glycogen in man. Decreased plasma amino acid concentrations have been reported after intravenous or per oral administration of leucine in man as well as after a single per oral dose in horses. In man, a negative correlation between the insulin response and the concentrations of isoleucine, valine and methionine have been shown but results from horses are lacking. This study aims to determine the effect of repeated per oral administration with a mixture of glucose and leucine on the free amino acid profile and the insulin response in horses after glycogen-depleting exercise.

Methods

In a crossover design, after a glycogen depleting exercise, twelve Standardbred trotters received either repeated oral boluses of glucose, 1 g/kg body weight (BW) at 0, 2 and 4 h with addition of leucine 0.1 g/kg BW at 0 and 4 h (GLU+LEU), or repeated boluses of water at 0, 2 and 4 h (CON). Blood samples for analysis of glucose, insulin and amino acid concentrations were collected prior to exercise and over a 6 h post-exercise period. A mixed model approach was used for the statistical analyses.

Results

Plasma leucine, isoleucine, valine, tyrosine and phenylalanine concentrations increased after exercise. Post-exercise serum glucose and plasma insulin response were significantly higher in the GLU+LEU treatment compared to the CON treatment. Plasma leucine concentrations increased after supplementation. During the post-exercise period isoleucine, valine and methionine concentrations decreased in both treatments but were significantly lower in the GLU+LEU treatment. There was no correlation between the insulin response and the response in plasma leucine, isoleucine, valine and methionine.

Conclusions

Repeated post-exercise administration with a mixture of leucine and glucose caused a marked insulin response and altered the plasma amino acid profile in horses in a similar manner as described in man. However, the decreases seen in plasma amino acids in horses seem to be related more to an effect of leucine and not to the insulin response as seen in man.  相似文献   
22.
Abstract

Extract

During the past two decades intestinal absorptive and secretory functions and the intestinal flora have been significantly clarified. Important concepts of intestinal dysfunction have emerged which have proved of immense clinical value(32) Moon, H. W. 1974. Pathogenesis of Enteric Diseases Caused by Escherichia coli. Adv. Vet. Sci. Comp. Med, 18: 179211. [PubMed] [Google Scholar] (39) Phillips, S. F. 1972. Diarrhoea: A Current View of the Pathophysiology. Gastroenterology, 63: 495518.  [Google Scholar] (46) Smith, H. W. 1965. Observations on the Flora of the Alimentary Tract of Animals and Factors Affecting its Composition. J. Pathol, 89: 95122.  [Google Scholar] (47) Smith, H. W. 1971. The Bacteriology of the Alimentary Tract of Domestic Animals Suffering from E. coli Infection. Ann. N. Y. Acad Set, 176: 110125.  [Google Scholar] (51) Soergel, K. H. 1973. New Concepts of Intestinal Function. Hepatogaslroenterol, 20: 351358.  [Google Scholar]. Despite this, the medical and economic consequences of diarrhoea continue to beset the cattle industry(1) Barnum, D. A., Glantz, P. J. and Moon, H. W. 1967. Colibacillosis. CIRVeterinary Monograph Series/Two, : 544.  [Google Scholar] (18) Hubbert, W. T. 1974. Factors Affecting Survival of the Bovine Fetus and Neonate. Theriogenology, 1: 1534.  [Google Scholar] (30) Marsh, H. 1968. Prenatal and Postnatal Mortality in Cattle. National Academy of Science. Pub. No. 1685,, : 16.  [Google Scholar] (56) Vollmar, R. E. 1974. Diarrhoea Control in a Dairy Operation. Mod Vet. Pract., 55: 509512.  [Google Scholar] (57) White, R. G. Scours-The Calf Killer. Presented at the California Livestock Symposium. An. Nut. Health, pp.1418.  [Google Scholar]. Diarrhoeal disease of the calf occurs at a time of complex developmental, environmental and functional change. The surface defences and enzyme systems of the neonatal gut are maturing in a protective film of maternal antibody, while undergoing increasing stimulation from environmental microbial challenge. The precarious nature of this defence system is not surprising. It is contingent upon a balance of such changing conditions as maternal antibody quantity, quality and delivery(5) Bush, L. J., Aguilera, M. A., Adams, G. D. and Jones, E. W. 1971. Absorption of Colostral Immunoglobulins by Newborn Dairy Calves. J. Dairy Sci., 54: 15471549.  [Google Scholar], environmental microbial challenge(46) Smith, H. W. 1965. Observations on the Flora of the Alimentary Tract of Animals and Factors Affecting its Composition. J. Pathol, 89: 95122.  [Google Scholar] (47) Smith, H. W. 1971. The Bacteriology of the Alimentary Tract of Domestic Animals Suffering from E. coli Infection. Ann. N. Y. Acad Set, 176: 110125.  [Google Scholar] and neonatal immunological and intestinal epithelial maturation(7) Corley, L. D., Staley, T. E., Bush, L. J. and Jones, E. W. 1977. Influence of Colostrum on Transepithelial Movement of E. coli 055. J. Dairy Sci., in press [Google Scholar] (52) Staley, T. E., Corley, L. D., Bush, L. J. and Jones, E. W. 1972. The Ultra-structure of Neonatal Calf Intestine and Absorption of Heterologous Proteins. A rial. Rec, 172: 559579. [Crossref], [PubMed] [Google Scholar]. While both infectious and non-infectious etiologic factors are involved(1) Barnum, D. A., Glantz, P. J. and Moon, H. W. 1967. Colibacillosis. CIRVeterinary Monograph Series/Two, : 544.  [Google Scholar] the former (Escherichia coli, Saltiionsllci and Shigella spp., and reo and corona viruses) is the more significant. Enteropathogenic E. coli (EPEC), a major contributor to neonatal diarrhoeal disease, will be discussed primarily. Four syndromes, septicaemia, enteric-toxaemia, local invasive and enterotoxic have been described(32) Moon, H. W. 1974. Pathogenesis of Enteric Diseases Caused by Escherichia coli. Adv. Vet. Sci. Comp. Med, 18: 179211. [PubMed] [Google Scholar] and ad verseoutcomes may result from endotoxic shock and/or hypovolemic shock, from systemic infection and from malnutrition. The clinician is thus faced with the selection of a multi-faceted approach to the problem. Avenues of attack, in addition to prophylactic husbandry, include: passive and active immunization, reduction of challenge, specific antimicrobial therapy, and resolution of fluid and electrolyte loss and shock. This presentation includes a resumé of the calf scour syndrome, together with observations concerning treatment and control. These observations include active and passive immunization, antimicrobial therapy, and modification of intestinal fluid loss.  相似文献   
23.
Reasons for Performing Study: Critical illness is associated with hyperglycemia in humans, and a greater degree and duration of hyperglycemia is associated with nonsurvival. Hypoglycemia is also seen in critically ill humans, and is associated with nonsurvival. This might also be true in the critically ill foal.
Objectives: To investigate the association of blood glucose concentrations with survival, sepsis, and the systemic inflammatory response syndrome (SIRS).
Methods: Blood glucose concentrations at admission (515 foals) and 24 hours (159 foals), 36 hours (95), 48 hours (82), and 60 hours (45) after admission were analyzed. Logistic regression analyses were performed to investigate the association of glucose concentrations with survival, sepsis, a positive blood culture, or SIRS.
Results: 29.1% of foals had blood glucose concentrations within the reference range (76–131 mg/dL) at admission, 36.5% were hyperglycemic, and 34.4% were hypoglycaemic. Foals that did not survive to hospital discharge had lower mean blood glucose concentrations at admission, as well as higher maximum and lower minimum blood glucose concentrations in the 1st 24 hours of hospitalization, and higher blood glucose at 24 and 36 hours. Foals with blood glucose concentrations <2.8 mmol/L (50 mg/dL) or >10 mmol/L (180 mg/dL) at admission were less likely to survive. Hypoglycemia at admission was associated with sepsis, a positive blood culture, and SIRS.
Conclusions and Potential Relevance: Derangements of blood glucose concentration are common in critically ill foals. Controlling blood glucose concentrations may therefore be beneficial in the critically ill neonatal foal, and this warrants further investigation.  相似文献   
24.
The present study was designed to evaluate three different in vitro fertilization (IVF) systems: a straw‐IVF system with 10 min of coincubation, a straw‐IVF system with 6‐h coincubation and the microdrop‐IVF system with 6‐h coincubation (the traditional IVF system used routinely in most of IVF laboratories) in an attempt to reduce polyspermic penetration ( Experiment 1 ). When the straw‐IVF system was tested in combination with two coincubation times, the use of 10 min of coincubation significantly increased (p < 0.001) the penetration rate and the efficiency of fertilization (67.7 ± 6.4% vs 31.9 ± 6.5% and 41.5 ± 2.5% vs 17.6 ± 2.5% for 10 min and 6 h, respectively), while there were no significant differences in the incidence of monospermy between both systems (64.3 ± 5.1% and 67.7 ± 3.4%, for 10 min and 6 h, respectively). The penetration rate in the 6‐h microdrop‐IVF system was higher (93.8 ± 3.6%; p < 0.001) compared with the 10‐min straw‐IVF system (67.7 ± 6.4%), however, monospermy was severely reduced (25.0 ± 4.3% vs 67.7 ± 3.4%, for the 6‐h microdrop‐IVF system and 10‐min straw‐IVF system, respectively). The efficiency of the IVF showed similar values between microdrop and 6‐h straw‐IVF systems, but efficiency was significantly improved (p < 0.05) when the 10‐min straw‐IVF system was used. Experiment 2 was designed to compare porcine in vitro embryo production in two IVF systems, the 6‐h microdrop‐IVF system (1000 sperm per oocyte) and 10‐min straw‐IVF system (30 000 sperm per oocyte). The blastocyst formation rates tended (p = 0.06) to be higher when the 10‐min straw‐IVF system was used compared with the 6‐h microdrop‐IVF system. In addition, the number of total cells per blastocyst increased significantly (p < 0.05) in the 10‐min straw‐IVF system. These results showed that the 10‐min straw‐IVF system is an effective way to decrease polyspermic penetration, and improve the efficiency of fertilization and the quality of blastocysts in terms of cell number per embryo.  相似文献   
25.
BACKGROUND: Hyperglycemia in critically ill humans is associated with increased glucose production and insulin resistance and is associated with death. This might also be true in horses presenting with acute abdominal disease. HYPOTHESIS: Throughout hospitalization, hyperglycemia will be common in adult horses presenting with acute abdominal disease. Hyperglycemia will be associated with a worse prognosis for survival to hospital discharge. ANIMALS: Two hundred sixty-nine adult horses with acute abdominal disease. METHODS: Observational retrospective study. Records were reviewed for 269 horses that had glucose data analysed and recorded at the time of hospital admission: 154 horses had a first sample after admission; 110 horses at 24 hours after admission; 74 horses at 36 hours after admission; and 49 horses at 48 hours after admission. Logistic regression analyses were performed to investigate the association of glucose concentrations with survival, in addition to the association of glucose concentrations with surgical, small intestinal, strangulating lesions, and lesions requiring a resection. RESULTS: Of 269 horses presenting with acute abdominal disease, 50.2% had blood glucose concentrations greater than the reference range (75.6-131.4 mg/dL); 0.4%, below the reference range; and 49.4%, within the reference range at admission. Of 269 horses, 2.3% had blood glucose concentrations below the reference range at some point during the first 48 hours of hospitalization, all of which had strangulating intestinal lesions. Horses that did not survive to hospital discharge had a higher mean blood glucose concentration at admission; at the first sample after admission; at 24, 36, and 48 hours after admission; and higher maximum and minimum blood glucose concentrations in the first 24 hours after admission. CONCLUSIONS AND CLINICAL IMPORTANCE: Derangements of blood glucose concentration are common in horses with acute abdominal disease. Hyperglycemia is much more common than hypoglycemia in these animals. Hyperglycemia in the first 48 hours of hospitalization is associated with a worse prognosis for survival to hospital discharge.  相似文献   
26.
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28.
The aim of this study was to evaluate the effects of hCG, progesterone and oestradiol supplementation on nuclear and cytoplasmic maturation of canine oocytes cultured for 24, 48, 72 and 96 h. Oocytes obtained from 18 healthy bitches were divided into three groups according to their reproductive status (follicular, luteal and anoestrus stages) and cultured in TCM 199 + 25 UI/ml of hCG + 1 μg/ml of progesterone + 1 μg/ml of 17‐β oestradiol or without hormonal supplementation (control) for different periods. Then, they were stained with FITC‐LCA‐Hoescht for chromatin configuration and cortical granules distribution and evaluated under an epifluorescence microscope. Culture time and the influence of different stages of the oestrous cycle were also evaluated. The present study demonstrated that there was no significant difference among the reproductive stages. With regards to culture medium, only oocytes from the supplemented medium were able to complete meiosis; however, significant difference was only noticed in the percentage of MI stage oocytes (p < 0.05) in the follicular and luteal group at 72 h of culture. Most oocytes in germinal vesicle, germinal vesicle breakdown and metaphase I stage had cortical granules distributed throughout the cytoplasm (immature pattern), irrespective of the culture period (p < 0.05). Cortical granules distributed immediately beneath the plasma membrane (mature) was only observed in metaphase II stage oocytes, but not all of them presented matured cytoplasm. Our results reveal that cortical granules distribution in canine oocytes matured in vitro did not progressed in correspondence with nuclear stage changes and are in accordance with those from other species.  相似文献   
29.
Seven critically ill foals that continued to be hypotensive despite fluid resuscitation and the infusion of dobutamine and/or dopamine were treated with an infusion of norepinephrine (noradrenaline). The norepinephrine was administered concurrently with dobutamine, and the combination therapy was titrated by use of indirect mean arterial pressure measurements. The highest dose of norepinephrine used was 1.5 mcg/kg/min. In six foals the administration of norepinephrine was associated with an increase in blood pressure. In one foal the mean arterial pressure did not increase in response to the doses of norepinephrine administered. All of the foals experienced an increase in urine output coincident with the start of the norepinephrine infusion. Three of the foal survived to hospital discharge.  相似文献   
30.
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