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991.
  1. The aim of this work was to improve natural anti-predator behaviour of farm-reared gamebirds.

  2. We evaluated the anti-predator behaviour of reared red-legged partridge Alectoris rufa chicks kept in brooder houses in large groups (>350 chicks), trained and not trained by parent red-legged partridges acting as experienced tutors.

  3. The experiment consisted of two conditioned tests (a raptor model and a human) and two control tests, which were conducted during three consecutive phases of life (1–4, 15–17 and 30–32 d after hatching). The motor anti-predator behaviour, its duration, the intensity of response in chicks and alarm calls elicited by adults were recorded.

  4. Tutors elicited aerial alarm calls (76% of tests) and showed prolonged crouching (59% of tests) in response to the raptor model whereas uttering the ground alarm call (73% of tests) and showing vigilance behaviour (78% of tests) was the main pattern during the human test.

  5. Trained and not trained chicks showed similar motor behaviour in response to the raptor model (crouching) and the human test (escaping), but frequency of strong responses (all chicks responding) from chicks trained with tutors was double that of chicks trained without them, and chicks trained with tutors showed a higher frequency of long responses (41–60 s).

  6. This study indicates that anti-predator training programmes before release may improve behaviour of farm-reared partridges which may confer benefits to survival of birds.

  相似文献   
992.
This report describes a case of cutaneous pythiosis in a 6‐year‐old female mixed breed dog, from the central west region of São Paulo State, Brazil. The cytological and histopathological analyses showed an intense inflammatory infiltrate with presence of numerous hyphal elements, suggesting infection due to Pythium insidiosum. The diagnosis was confirmed by nested‐PCR, which was carried out with specific primers derived from the ribosomal DNA region. The pathogen occurs in Brazil and veterinarians should be aware of the importance of correctly diagnosing this disease and differentiating it from other fungal diseases.  相似文献   
993.
Background: Omeprazole and famotidine both reduce severity of exercise‐induced gastritis, but administering famotidine is easier than administering omeprazole during racing competition. Hypothesis: Famotidine is more efficacious than no treatment in reducing severity of exercise‐induced gastritis; and high‐dose famotidine is more efficacious than omeprazole in reducing severity of exercise‐induced gastritis. Animals: Experiment 1: Randomized placebo‐controlled study, 36 sled dogs (3–8 years); Experiment 2: Randomized positive‐control study, 52 sled dogs (2–8 years). Methods: Experiment 1: Equal numbers of dogs randomly assigned to famotidine (20 mg q24h) or no treatment groups. Gastroscopy was performed 24 hours after the dogs ran 330 miles. Mucosal appearance was blindly scored by previously described scoring system. Experiment 2: Equal numbers of dogs randomly assigned to omeprazole (20 mg q24h) or high‐dose famotidine (40 mg q12h) groups. Gastroscopy was performed 48 hours before and 24 hours after the dogs ran 300 miles. Mucosal appearance was blindly scored by previously described scoring system. Results: Famotidine reduced the prevalence of clinically relevant, exercise‐induced gastric lesions compared with no treatment (7/16 versus 11/16, P= .031). Compared with high‐dose famotidine, omeprazole significantly decreased the severity (0.4 versus 1.2, P= .0002) and prevalence (2/23 versus 7/21, P= .049) of gastric lesions. Conclusions and Clinical Relevance: Although famotidine provides some benefit in the prevention of exercise‐induced gastric lesions, omeprazole is superior to famotidine in preventing gastritis in dogs running 300 miles. Routine administration of omeprazole is recommended to prevent stress‐associated gastric disease in exercising and racing Alaskan sled dogs.  相似文献   
994.
Background: Release of myelin basic protein (MBP) into the cerebrospinal fluid (CSF) is associated with active demyelination and correlates with outcome in various neurological diseases. Hypothesis/Objectives: To describe associations among CSF MBP concentration, initial neurological dysfunction, and long‐term ambulatory outcome in dogs with acute thoracolumbar intervertebral disk herniation (IVDH). Animals: Five hundred and seventy‐four dogs with acute thoracolumbar IVDH and 16 clinically normal dogs. Methods: Prospective case series clinical study. Signalment, initial neurological dysfunction as determined by a modified Frankel score (MFS), and ambulatory outcome at >3‐month follow‐up were recorded. Cisternal CSF MBP concentration was determined by an ELISA. Associations were estimated between CSF MBP concentration and various clinical parameters. Results: Dogs with thoracolumbar IVDH that did not ambulate at follow‐up had a higher CSF MBP concentration (median, 3.56 ng/mL; range, 0.59–51.2 ng/mL) compared with control dogs (median, 2.22 ng/mL; range, 0–3.82 ng/mL) (P= .032). A CSF MBP concentration of ≥3 ng/mL had a sensitivity of 78% and specificity of 76% to predict an unsuccessful outcome based on receiver‐operating characteristics curve analysis (area under the curve =0.688, P= .079). Affected dogs with a CSF MBP concentration ≥3 ng/mL had 0.09 times the odds of ambulation at follow‐up compared with affected dogs with CSF MBP concentration <3 ng/mL when adjusted for initial MFS (95% confidence interval 0.01–0.66, P= .018). Conclusions and Clinical Importance: These results would suggest that CSF MBP concentration may be useful as an independent prognostic indicator in dogs with thoracolumbar IVDH.  相似文献   
995.
An experiment was conducted to determine if exogenous luteinizing hormone-releasing hormone (LHRH) administered iv intermittently as pulses (P) or by continuous sc infusion (I) using osmotic minipumps could sustain pulsatile LH release and induce estrous cyclicity in prepubertal heifers. Prepubertal heifers were assigned randomly to: 1) receive pulses of LHRH (n = 6; 2.5 micrograms LHRH/2 h for 72 h), 2) be infused with LHRH (n = 11; 1.25 micrograms LHRH/h for 72 h), or 3) serve as controls (n = 16). Blood was collected at 20-min intervals for 8 h (0900 to 1700 h) from six heifers in each group on d 1, 2, 3 (during treatment), and on d 4 (during 8 h after terminating LHRH treatments). Heifers given LHRH had higher (P less than .01) LH concentrations than controls. Preovulatory-like LH surges occurred in three I, two P and no control heifers during treatment. Pulse frequencies of LH (no. LH pulses/8 h) were greater (P less than .001) for P heifers than for I and control heifers due to pulsatile LHRH treatment. Serum estradiol was higher (P less than .01) during treatment for LHRH-treated heifers than for controls. Serum follicle-stimulating hormone, cortisol, and progesterone were unchanged during treatment. High levels of cortisol on d 1 declined (P less than .001) to baseline by d 2. Characteristic progesterone rises or short luteal phases occurred within 10 d of treatment initiation in more (P less than .05) LHRH-treated heifers (I = 45%, P = 33%) than controls (6%), although days to first observed estrus and first ovulation were unaffected by treatments. Although both continuous and pulsatile administration of LHRH successfully induced LH and estradiol release as well as preovulatory-like LH surges in some heifers, earlier initiation of estrous cycles was not achieved. Estrous cycles appeared to be delayed by exposure to continuous LHRH infusions during the peripubertal period.  相似文献   
996.
The cardiopulmonary consequences of diazepam (0.5 mg/kg, IV) followed by ketamine (10 mg/kg, IV) were evaluated in 11 dogs. Diazepam did not exhibit a tranquilizing effect and was frequently associated with excessive excitement. It produced minimal cardiopulmonary effects, except for a significant increase in heart rate. Ketamine administration was associated with less cardiovascular stimulation when administered after diazepam than it did when administered alone; the respiratory depression was greater. Compared with ketamine alone, the diazepam-ketamine combination was associated with more vomition, less muscle hypertonus, less seizure activity, and less salivation.  相似文献   
997.
Coccidiosis in swine   总被引:1,自引:0,他引:1  
It is clear that although the clinical history, pathologic lesions, and endogenous stage life cycle of I. suis are well understood, the epidemiology of this parasite is not understood or is misunderstood. Consequently, treatment of individual piglets and prophylactic use of coccidiostats in sows have not been consistently rewarding. The best control at present is achieved through use of extensive sanitation, particularly steam cleaning. The incidence of clinical coccidiosis in piglets continues to be a major component (approximately 20 per cent) in the differential etiology of scours in baby pigs.  相似文献   
998.
Left displacement of the abomasum was diagnosed radiographically in an 8-week-old female Friesian calf. At surgery, a 4 cm ulcer was repaired and an abomasopexy performed during closure of the abdomen. Recovery from surgery was slow, and regurgitation of rumen contents occurred. Despite medical treatment, the calf died 4 days later. Left abomasal displacement is a well documented disease of dairy cattle (Robertson 1968; Coppock 1974; Martin et al 1978a; Poulsen 1976), but in young calves the condition is rare (Dirksen 1981). This report describes a case of left abomasal displacement with ulceration in an 8-week-old female Friesian calf.  相似文献   
999.
The agar gel precipitation test was used to detect rotavirus antibodies in the serum of 562 calves and bovine rotavirus antigen in the feces of 347 calves. Significantly more females had rotavirus antibodies in the serum (P less than 0.01) and rotavirus antigen in the feces (P less than 0.1) than did male calves. Female buffalo calves were also found to be more susceptible than male buffalo calves to rotavirus infection.  相似文献   
1000.
7 病原-宿主关系的改变以及宿主内的疾病过程 如上所述,改变宿主和疾病病原之间的关系可能会使病原自身发生变化,或者会引起宿主之间的疾病过程变化以及传染原在宿主间的传播变化。 通常来说,当宿主很少暴露给特定病原时,由于缺少先天性抵抗力(由遗传决定)和未经免疫的宿主,从而使最严重的疾病症状得以发生,易感年龄间变化最小。宿主先天性抵抗力可能受到一定程度的自然因素或人为的管理因素作用,尤其是在最严重或最麻烦的疾病方  相似文献   
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