Effect of book size and age of mare and stallion on foaling rates in thoroughbred horses     

K.J. McDowell PhD  D.G. Powell BVSc  C.B. Baker DVM   《Journal of Equine Veterinary Science》1992,12(6):364-367

The entire population data for Thoroughbred horses in the United States, Canada and Puerto Rico registered with the Jockey Club of America were utilized to study the effect of stallion book size, age of mare and age of stallion on live foal percentage for the 1987 and 1988 breeding seasons. There were 17,260 stallions bred to 179,009 mares, with a resulting overall live foaling rate of 58.1%. There was an increase in live foal percentage as book size increased (P<0.001) and a decrease in live foal percentage as mare age increased (P<0.0001). Stallion age had no effect on live foal percentage.  相似文献   

Effect of intracerebroventricular orexin-B on food intake in sheep.   总被引：6，自引：0，他引：6  

J L Sartin  C Dyer  R Matteri  D Buxton  F Buonomo  M Shores  J Baker  J A Osborne  T Braden  B Steele 《Journal of animal science》2001,79(6):1573-1577

Orexin is a hypothalamic neuropeptide that regulates feeding behavior in rats. Orexin-B has recently been cloned in pigs and was shown to stimulate food intake after intramuscular injection. This study was designed to determine whether intracerebroventricular (ICV) and intravenous injections of orexin could regulate appetite in sheep. Suffolk wethers were moved to indoor facilities, adapted to diets for 6 wk, and trained to stand in stanchions for 3 to 6 h each day for 2 wk before indwelling ICV cannulas were installed. These sheep were provided water and they consumed feed ad libitum. On the day before an experiment, each sheep was cannulated in a jugular vein. On the day of an experiment, sheep were placed in stanchions and allowed to stand for 1 h before use. Sheep were then monitored over a 2-h control period before i.v. injection with saline or porcine orexin-B (3 micrograms/kg BW) or ICV injection with artificial cerebrospinal fluid (CSF), orexin (0.03, 0.3, or 3 micrograms/kg BW) or in a second experiment with either orexin B (0.03, 0.3, 3 micrograms/kg BW), neuropeptide-Y (NPY; 0.3 microgram/kg BW), or orexin plus NPY. Food intake was monitored for consecutive 2-h periods. The i.v. injections of orexin did not affect food intake or metabolite or hormone concentrations. In ICV sheep, orexin increased food intake at 2 (P < 0.04) and at 4 h (P < 0.02). Food intake was greatest with the 0.3 microgram/kg BW dosage of orexin (P < 0.05). In the first 2 h after injection, orexin had an effect similar to that of NPY (0.23 kg for orexin and 0.2 kg for NPY). The combination of NPY and orexin had a greater effect on food intake (to 0.34 kg) than did either orexin (P < 0.05) or NPY (P < 0.008) alone. Differences were not apparent in the subsequent 2-h interval. No differences were noted in free fatty acid, glucose, growth hormone, luteinizing hormone, or insulin concentrations following orexin injection. There was an effect of ICV orexin treatment on plasma cortisol concentrations (P < 0.002). Cortisol was increased by orexin at the 0- to 2-h (P < 0.008) and in the 2- to 4-h (P < 0.009) intervals after orexin injection. These data indicate that central administration of orexin stimulates feed intake in sheep.  相似文献   

Study on the etiologic role of bovine respiratory syncytial virus in pneumonia of dairy calves   总被引：6，自引：0，他引：6  

J C Baker  R E Werdin  T R Ames  R J Markham  V L Larson 《Journal of the American Veterinary Medical Association》1986,189(1):66-70

Bovine respiratory syncytial virus (BRSV) was the viral agent most commonly identified in 14 epizootics of pneumonia in dairy calves. A microtiter serum-virus neutralization test proved to be the best means of identifying involvement of BRSV; seroconversion (fourfold or greater rise in titer) was demonstrated in 10 of the 14 epizootics. Only limited involvement of bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, parainfluenza 3 virus, and bovine adenovirus type 3 was recognized. Pasteurella multocida was isolated in 12 of 14 epizootics, and Pasteurella haemolytica in 4 of 14 epizootics. Mycoplasmal and ureaplasmal agents were isolated in all 14 epizootics.  相似文献   

Arsenic-sulfur amino acid interactions in the chick     

G L Czarnecki  D H Baker  J E Garst 《Journal of animal science》1984,59(6):1573-1581

Experiments were conducted with growing crossbred chicks to determine the reasons why cysteine exacerbates roxarsone (3-nitro-4-hydroxyphenylarsonic acid) toxicity. A fortified corn-soybean meal diet that met or exceeded all nutrient requirements of the young chick was fed. While cysteine enhanced roxarsone toxicity, it had little effect on the toxicity of the inorganic arsenicals As2O3 and As2O5. The toxicity of another pentavalent organic arsenical, phenylarsonic acid, was also exacerbated by cysteine. In contrast, the growth-depression resulting from feeding the trivalent form of phenylarsonic acid, i.e., phenylarsine oxide, was not affected by dietary addition of cysteine. Supplementation of the diet with cystine, methionine or K2SO4 did not exacerbate roxarsone toxicity. Reduced glutathione (GSH), however, slightly increased the gain/feed depression resulting from feeding 300 mg roxarsone/kg diet. When injected ip 1) roxarsone and cysteine, or 2) roxarsone and ascorbic acid killed 100 or 60% of the birds, respectively, within 48 h postinjection. Few (6.7%) deaths resulted from ip injections of the same level of roxarsone alone. Therefore, the potentiation of toxicity requires pentavalent organic arsenicals and compounds that can act as reducing agents. We concluded that cysteine exacerbates roxarsone toxicity by reducing it to the more toxic trivalent state.  相似文献   

Comparison of the efficacy of ivermectin, oxibendazole, and pyrantel pamoate against 28-day Parascaris equorum larvae in the intestine of pony foals     

S M Austin  J A DiPietro  J H Foreman  G J Baker  K S Todd 《Journal of the American Veterinary Medical Association》1991,198(11):1946-1949

Sixteen helminth-free pony foals were inoculated with a mean (+/- SD) 2,000 (+/- 545.5) infective Parascaris equorum eggs (day 0). Foals were allocated to replicates of 4, and treatments within each replicate were assigned at random. Treatment administered on postinoculation day (PID) 28 included no treatment (control), 0.2 mg of ivermectin/kg of body weight, 10 mg of oxibendazole/kg, or 6.6 mg of pyrantel base (pamoate)/kg. Paste formulations of the anthelmintics were administered orally. The foals were euthanatized 14 days after treatment (PID 42) and examined for P equorum larvae in the small intestine. The mean +/- SD (and range) numbers of fourth-stage P equorum larvae recovered from nontreated foals and those treated with ivermectin, pyrantel, or oxibendazole were 1,603.8 +/- 1,026.8 (305 to 2,480), 29.3 +/- 55.8 (0 to 113), 413.0 +/- 568.1 (0 to 1,204), or 889.5 +/- 1,123.1 (1 to 2,345), respectively. Compared with the value for control (nontreated) foals, treatment with ivermectin, pyrantel, and oxibendazole was 98.2, 74.2, and 44.5% effective, respectively, when administered 28 days after experimentally induced infection with P equorum. Adverse reactions attributable to treatment were not observed.  相似文献   

Effect of dexamethasone on bovine leukocyte functions and bovine herpesvirus type-1 replication.   总被引：1，自引：0，他引：1       下载免费PDF全文

H B Ohmann  P E Baker    L A Babiuk 《Canadian journal of veterinary research》1987,51(3):350-357

In an attempt to elucidate the mechanism whereby dexamethasone could reactivate bovine herpesvirus type-1 the effect of dexamethasone on virus replication and leukocyte functions was assessed. No effect was detectable on either virus yield or in vitro replication kinetics. In contrast, dexamethasone influenced several leukocyte functions thought to be of importance in antiviral defense and maintenance of latency. In vitro exposure of peripheral blood polymorphonuclear neutrophilic granulocytes of normal animals to dexamethasone depressed their migratory and cytotoxic activities, but had no effect on Fc- and complement receptor expression. Dexamethasone also depressed lectin-induced lymphocyte proliferation and interleukin-2 generation in a dose-dependent manner. When cows were treated repeatedly with dexamethasone and their leukocytes assayed, suppression of phytohemagglutinin-induced lymphocyte proliferation, interleukin-2 generation, natural cytotoxicity of mononuclear cells and polymorphonuclear neutrophilic granulocyte functions were observed. In contrast, concanavalin A induced lymphocyte proliferation was increased following treatment.  相似文献   

Amino acid excesses for young pigs: effects of excess methionine, tryptophan, threonine or leucine   总被引：4，自引：0，他引：4  

M S Edmonds  D H Baker 《Journal of animal science》1987,64(6):1664-1671

Five experiments involving 359 weanling (8 kg) pigs were conducted to evaluate the effects of dietary excesses of DL-methionine (Met), L-tryptophan (Trp), L-threonine (Thr) or L-leucine (Leu) when added to a 20% crude protein corn-soybean meal (C-SBM) diet. Experiments involved supplementing the basal diet with 0, .5, 1.0, 2.0 or 4.0% excesses of Met, Trp or Thr, or in the case of Leu, a 0, 1.0, 2.0, 4.0 or 6.0% excess. Levels of .5 and 1.0% excess Met did not depress feed intake (FI), weight gain (G) or gain/feed (G/F); 2.0 and 4.0% additions, however, depressed both FI and G but not G/F. Free Met in blood plasma increased linearly as dietary Met level increased, reaching over a 100-fold elevation at the highest Met level fed. Plasma Thr and serine (Ser) increased, and glycine (Gly) decreased, with each added increment of Met. With Trp, only the 4.0% addition depressed FI and G (but not G/F). None of the levels of excess Thr depressed performance. Excess Thr, in fact, tended to increase G/F. Free Thr, Ser and Gly in plasma increased linearly as graded increments of excess Thr were added to the diet. With Leu, a 6% addition depressed weight gain and food intake (but not G/F) but 1, 2 or 4% excesses were without effect. Plasma free Leu increased linearly while free isoleucine and valine decreased as graded increments of Leu were added to the diet. These results suggest that pigs can tolerate considerable excesses of Met, Trp, Thr and Leu without experiencing decreased voluntary feed intake or weight gain.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Protection against ovine footrot using a topical preparation of zinc sulphate     

DJ MARSHALL  RI WALKER  RE COVENY 《Australian veterinary journal》1991,68(5):186-188

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Exploratory celiotomy for suspected urinary tract disruption in neonatal foals: a review of 18 cases   总被引：1，自引：0，他引：1  

R Adams  A M Koterba  T C Cudd  W A Baker 《Equine veterinary journal》1988,20(1):13-17

The medical records of 18 neonatal foals, in which exploratory celiotomies were performed for suspected urinary tract lesions, were reviewed. Despite clinical signs and laboratory values indicative of disruption of the urinary tract, three foals did not have a site of urinary tract leakage at surgery. Eight foals had ruptured bladders and seven foals had urachal lesions. Ultrasonography was used as a pre-operative diagnostic procedure in eight foals to evaluate the presence of free peritoneal fluid and urinary tract integrity. Nine foals were alive six months after discharge. Seven of the nine non-surviving foals died or were destroyed because of fungal or bacterial infections.  相似文献   

Possible therapeutic benefits of adenosine-potentiating drugs in reducing age-related degenerative disease in dogs and cats     

Scaramuzzi RJ  Baker DJ 《Journal of veterinary pharmacology and therapeutics》2003,26(5):327-335

Adenosine is a ubiquitous, biologically important molecule that is a precursor of other biologically active molecules. It also is a component of some co-factors and has distinct physiological actions in its own right. Levels are maintained by synthesis from dietary precursors and re-cycling. The daily turnover of adenosine is very high. Adenosine can act either as a hormone by binding to adenosine receptors, four adenosine receptor subtypes have been identified, and as an intracellular modulator, after transport into the cell by membrane transporter proteins. One of the principal intracellular actions of adenosine is inhibition of the enzyme phosphodiesterase. Extracellular adenosine also has specific neuromodulatory actions on dopamine and glutamate. Selective and nonselective agonists and antagonists of adenosine are available. The tasks of developing, evaluating and exploiting the therapeutic potential of these compounds is still in its infancy. Adenosine has actions in the central nervous system (CNS), heart and vascular system, skeletal muscle and the immune system and the presence of receptors suggests potential actions in the gonads and other organs. Adenosine agonists improve tissue perfusion through actions on vascular smooth muscle and erythrocyte fluidity and they can be used to improve the quality of life in aged dogs. This article reviews the therapeutic potential of adenosine-potentiating drugs in the treatment of age-related conditions in companion animals, some of which may be exacerbated by castration or spaying at an early age.  相似文献