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991.
Comminuted first phalanx fractures were diagnosed in 30 horses. One leg was involved in each horse. Five horses were presented with open fractures. Nine horses had a portion of intact cortex (strut) extending from the proximal to distal joint. Ten horses were euthanized, including one with an open fracture, without treatment. The remaining 20 horses were treated by open reduction with a neutralization plate (8 horses, including one with an open fracture), open reduction with lag screw fixation (3 horses), lag screw fixation through stab incisions (2 horses), external coaptation with a cast (3 horses), and external skeletal fixation using a weight supporting shoe (4 horses, including 3 with open fractures).
Thirteen horses were euthanized following treatment because of persistent infection (9), chronic lameness (2), and third metacarpal bone fractures (2). Seven horses survived longer than 1 year after treatment. Six were lame and used as breeding animals, and one horse went on to race successfully. All four horses with open fractures that were treated were subsequently euthanized.
Significantly more horses with an intact strut of bone survived after treatment (4 of 7 [57%]) when compared to horses without an intact strut of bone that were treated (3 of 13 [23%]) (p < 0.05).
Invasive surgical approaches used for the repair of comminuted first phalanx fractures in this study were associated with an unacceptable infection rate (55%). Techniques involving less trauma to the compromised soft tissue around the fracture should afford a better chance for a successful outcome.  相似文献   
992.
993.
Bovine mycotic abortion in some counties of the Irish provinces of Leinster and Ulster was estimated at 1–2% of all abortions for which a causal agent was identified in the years from 1969 to 1978. The organism most commonly isolated from diseased specimens wasAspergillus fumigatus, followed byAbsidia corymbifera. There was no relationship between the incidence of the disease in any year and the rainfall or number of raindays during the previous summer. The data obtained are discussed in relation to the occurrence of the disease in the United Kingdom.  相似文献   
994.
Psittacine inclusion body hepatitis in an aviary   总被引:1,自引:0,他引:1  
Psittacine inclusion body hepatitis (also known as Pacheco's parrot disease) was believed to be responsible for fatal necrotizing hepatitis and splenitis in a variety of psittacine birds from a private aviary. Splenic cells and degenerative hepatocytes around the outer zone of necrotic areas had margination of nuclear material and large intranuclear inclusion bodies. Clinical signs consisted of weakness, anorexia, vomiting, loose feces, and slight ruffling of feathers. The source of the infection was undetermined, but could have been associated with 3 Patagonian conures within the aviary. Patagonian conures are well-recognized as clinically normal carriers. The outbreak was limited by strict quarantine and disinfection of the aviary for 14 days.  相似文献   
995.
Stimulation of swine growth by porcine growth hormone   总被引:7,自引:0,他引:7  
Highly purified porcine growth hormone (pGH; USDA-B1) was administered by im injection (22 micrograms X kg body weight-1 X d-1) to rapidly growing Yorkshire barrows for 30 d. Growth hormone significantly increased growth rate (10%), feed efficiency (4%), cartilage growth and muscle mass. However, pGH did not affect carcass adipose tissue mass. Intramuscular lipid content of the longissimus was increased 50% by pGH administration. Plasma pGH concentration was elevated (7- to 11-fold) for 3 to 5 h post-injection. Chronic administration of pGH depressed pituitary GH content and concentration approximately 45%. No GH antibodies were detected in the plasma of GH-treated swine. Plasma somatomedin-C concentration was increased 55% by GH treatment 3 h post-injection. Plasma glucose and insulin concentrations were both significantly increased in GH-treated swine, suggesting that the animals had developed a state of insulin resistance. Plasma-free fatty acid concentration tended to be higher in GH-treated animals. Treatment of swine with pGH significantly decreased plasma blood urea nitrogen. Assessment of animal health during the trial and postmortem indicated that pGH administration did not have any adverse effects. In summary, treatment of young, rapidly growing swine with pGH stimulated growth performance without affecting animal health or inducing the production of GH antibodies.  相似文献   
996.
Clavulanic acid (CA) competitively inhibits beta-lactamase hydrolysis of penicillins in vitro. Treatment with amoxycillin combined with clavulanic acid (A-CA) was compared with placebo in a blind study in cats with experimental cystitis caused by Escherichia coli demonstrating in vitro resistance to amoxycillin. Bacterial cystitis was induced in 20 cats by bladder infusion of 5 ml of 0.05 per cent alcoholic salicylic acid followed after 24 hours by a brain-heart infusion broth of E coli (10(8) colony forming units ml-1) previously found to be resistant to amoxycillin in vitro (minimum inhibitory concentration over 512 micrograms ml-1). Four days after infection, cats were randomly divided into two groups of 10 and treated with amoxycillin combined with clavulanic acid or placebo for 10 days. When compared to the placebo-treated group, the A-CA treated group showed: reduced quantitative bacterial counts in urine on days 7 (P less than 0.001) and 14 (P less than 0.02); reduced culture positive urine on days 7 (P less than 0.001) and 14 (P less than 0.001); and less severe inflammation on histological examination of the bladder and urethra (P less than 0.01). It was concluded that A-CA was effective in reducing the bacterial count and reducing the histopathological changes in the bladder and urethra in an experimental model of acute bacterial cystitis in cats infected with an E coli demonstrating in vitro resistance to amoxycillin.  相似文献   
997.
Pre-laying behaviour in battery cages   总被引:1,自引:0,他引:1  
The pre-laying behaviour of hens from two strains of domestic fowls housed in battery cages was studied. Hens from one strain exhibited stereotyped pacing before laying, whereas hens from the other tended to sit during the pre-laying period. Hens from both strains performed vacuum nest-building behaviour before laying. Implications of these findings in relation to the improvement of animal welfare are discussed.  相似文献   
998.
Inhibitory effect of the bovine conceptus on lymphocyte stimulation   总被引:1,自引:0,他引:1  
Experiments were conducted to determine whether the preimplantation bovine conceptus produces an immunosuppressant as measured by the inhibition of lectin-induced incorporation of thymidine into lymphocytes. The results of the experiments clearly indicated that media from cultured 18-d-old embryos inhibited lectin-induced incorporation of thymidine into bovine lymphocytes. The inhibitory substance was not produced by heat-killed cells from the conceptus, was not toxic to lymphocytes, was not lectin-specific, but did act in a partially reversible manner. The inhibitor had no apparent effect on porcine lymphocytes, a moderate effect on ovine lymphocytes and a potent effect on bovine lymphocytes. The substance appeared to have a molecular weight of between 500 and 10,000 and was ether insoluble and heat stable. The possible chemical nature of the inhibitor and its potential effect on survival of the preimplantation conceptus are discussed.  相似文献   
999.
Polyacrylamide gel electrophoresis was used to compare serum taken from ponies before and during clinical illness confirmed as grass sickness. A consistent rise in the level of haptoglobin was seen in serum from animals which had shown symptoms for more than two days. Serum albumin was also shown to have altered mobility at the onset of clinical disease. Estimation of the haemoglobin-binding capacity confirmed the haptoglobin increase. This haptoglobin has been purified and some of its properties determined. In contrast to the situation in acute inflammatory conditions no other acute-phase proteins increased to a significant extent in grass sickness. It is concluded that the neurotoxin known to be present in sera of animals experiencing acute grass sickness cannot itself be detected by polyacrylamide gel electrophoresis but may be bound to serum albumin.  相似文献   
1000.
Twenty-one experimental oil-emulsion vaccines with different emulsifier contents, aqueous-to-oil ratios, and antigen concentrations were compared by immunization of 4-week-old chickens. Vaccines that contained oil-phase (Arlacel 80) and aqueous-phase (Tween 80) emulsifiers induced 2-to-4-fold higher hemagglutination-inhibition titers than vaccines with only the oil-phase emulsifier. The emulsion vaccines containing both emulsifiers were also more stable at 37 C and less viscous than those containing only the oil-phase emulsifier. Vaccines that had different aqueous-to-oil ratios and contained different quantities of allantoic-fluid antigen (1.2% to 50% of the vaccine volume) induced similar protection against challenge, but hemagglutination-inhibition titers were proportional to the amount of antigen added. Vaccines that had different aqueous-to-oil ratios but contained equal amounts of antigen induced similar hemagglutination-inhibition titers and similar protection against challenge.  相似文献   
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