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991.
Adult Suffolk ewes (n = 14) were treated on d 10 of the estrous cycle with anti-bovine luteinizing hormone (LH) antiserum. Control ewes (n = 10) were treated with normal horse serum. Estrous behavior and the number of corpora lutea and ovarian follicles were examined at the subsequent estrous cycle. Daily plasma concentrations of progesterone (P4), follicle stimulating hormone (FSH) and estradiol were determined before and after treatment. Ewes treated with antiserum had a higher (P less than .05) ovulation rate (2.7 +/- .2) than did controls (2.1 +/- .1). No differences were found in the numbers of large (greater than 5 mm) or small (less than 5 mm) follicles between treatment groups. Estrus was delayed (P less than .025) approximately .6 d/in ewes treated with antisera. Immunoreactive FSH increased (P less than .05) within 1 d after treatment and remained higher than the controls for 5 d. Peak estradiol concentrations occurred on d 17 for treated ewes compared with peak concentrations on d 15 or 16 for control ewes. The P4 concentrations were generally less (P less than .025) in treated ewes throughout the luteal phase of the treatment cycle. These data demonstrate that ovulation rate is increased in ewes treated with LH antiserum. The marked increase in plasma FSH suggests a possible mechanism whereby ovulation rate is enhanced.  相似文献   
992.
Lactic acid as a decontaminant in slaughter and processing procedures   总被引:1,自引:0,他引:1  
An attempt was made to interrelate the data obtained in experiments conducted by our Department along beef, veal and pig slaughter lines, using lactic acid (LA) for the decontamination of carcasses, cold and hot boned primal cuts, slaughter byproducts, and butcher's knives. First and foremost it was observed, that provided Good Manufacturing Practices are strictly followed, the microbial load of carcass surfaces will be substantially reduced. LA-decontamination may result in an additional reduction. Since in the early post-mortem period bacteria are not yet attached to the meat surface, LA-decontamination should preferably be applied to the hot carcass. It was demonstrated that, dependent on mode and duration of application, LA sprays not exceeding 1% v/v (beef), 1.25% v/v (veal) and 1.5% v/v (pork) resulted in acceptable carcass colour scores. Blood spots, which are particularly prone to discolouration by lactic acid application, should be removed at an early post-mortem stage e.g. by strong showering. The difference in surface pH between LA-treated and control carcasses disappeared within 72 hours post-mortem. Veal longissimus chops treated with LA solutions up to 2% v/v were not identified by a consumer taste panel as significantly different from controls. The 'immediate' bactericidal effect of LA-decontamination for beef, veal and pig carcasses, as well as for pig liver and veal brain, amounted to approximately 1.5 log cycles for the aerobic colony counts, strongly dependent on substrate and conditions of decontamination. In addition, a 'delayed' bacteriostatic effect was observed during storage, which is probably the result of a prolonged lag phase of acid-injured micro-organisms surviving lactic acid decontamination.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
993.
On the basis of clinical and laboratory examinations, a ventricular septal defect or a variant of the tetralogy of Fallot was suspected in a 3-year-old filly with a history of poor growth rate and exercise intolerance. The filly was euthanatized and found to have a 3-chambered heart (cor triloculare biatriatum). The heart had 2 normally formed atria and a large common ventricle into which the right and left atrioventricular orifices opened and from which the aorta arose. There was a small separate chamber from which the pulmonary trunk originated. This chamber communicated with the common ventricle through a large oval opening along the dorsal border of the displaced, interventricular septum.  相似文献   
994.
995.
The ram is an important member of the flock, particularly in smaller, intensively managed flocks such as are found in the Northeast. An infertile ram can spell reproductive and financial failure for the producer. A highly fertile ram can settle more ewes in a shorter time, produce more twins, and confer valuable traits on his offspring. These include wool type, rate of gain and higher sperm production and ovulation rates. Details of the breeding soundness examination, including semen evaluation are discussed. Ram management techniques appropriate for Northeastern sheep producers are presented.  相似文献   
996.
Potentiation of the antibody response to inactivated bovine viral diarrhea virus by immunological adjuvants was studied in guinea pigs and cattle. The inactivated bovine viral diarrhea virus alone was demonstrated to be a weak immunogen. Addition of either 2 mg per mL diethylaminoethyl-dextran or 5% alhydrogel to inactivated bovine viral diarrhea virus did not or only slightly stimulated the antibody response; the combined adjuvants induced a significantly higher titer. A higher concentration (20 mg per mL) of diethylaminoethyl-dextran, on the contrary, suppressed the immune potentiation by the dual adjuvants. Combination of Bordetella bronchiseptica and alhydrogel adjuvants stimulated a high titer of antibody. The titer was further elevated upon revaccination and was significantly higher than that induced by alhydrogel alone. In cattle, alhydrogel enhanced the immune response and the additional inclusion of diethylaminoethyl-dextran did not cause a significant potentiation of the immunity. However, the antibody decay rate was significantly slower when stimulated by the combined adjuvants.  相似文献   
997.
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   
998.
999.
Breed-related risk factors for canine parvovirus enteritis   总被引:2,自引:0,他引:2  
Case records of 305 dogs with canine parvovirus (CPV) enteritis, seen at the Veterinary Hospital of the University of Pennsylvania from July 1, 1981 to Aug 31, 1982, were selected on the basis of admitting diagnoses or signs of diarrhea and vomiting. The case records were subdivided into 3 diagnostic categories, based on final diagnoses and laboratory test results. There were 96 dogs with definite CPV enteritis, 139 with possible CPV enteritis, and 70 with unlikely CPV enteritis. These cases were then stratified by animal's age (less than or equal to 6 months or greater than 6 months) and specific hospital service (medicine or emergency). A control group was selected from all canine case records from the Veterinary Hospital of the University of Pennsylvania for conditions other than the criteria used in selecting the case group. Approximately 2 hospital patients were selected for each CPV enteritis case by frequency matching for hospital service and age. The proportion of dogs with definite CPV enteritis that had each of the clinical signs that were studied was greater than that of dogs in the other CPV enteritis diagnostic categories. The overall survival rate for dogs with definite CPV enteritis was 64.0%; survival was not associated with any given clinical sign of disease. Odds ratios (OR) for the risk of CPV enteritis were calculated for breeds with 3 or more dogs with definite CPV enteritis. The Doberman Pinschers (OR = 3.1), Rottweilers (OR = 6.0), and English Springer Spaniels (OR = 8.1) had a significantly increased risk of CPV enteritis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
1000.
The effects of Escherichia coli heat-stable enterotoxin (ST) on chloride efflux rate were investigated in 3 fractions of enterocytes isolated in a villus-to-crypt gradient from porcine jejunum. There was no difference in chloride efflux rates between mature and immature cells from controls. Heat-stable enterotoxin significantly increased chloride efflux in all fractions. Morphine inhibited ST-augmented secretion in mature enterocytes. Atropine or clonidine had no effect. Calcium efflux rates and glucose or glutamic acid metabolism were not altered by ST. The results indicate that ST may stimulate chloride secretion in both villus and crypt cells and that opiates inhibit intestinal secretion by a direct action on villus epithelial cells.  相似文献   
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