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1.
In mid-September, 1 month before the insertion of intravaginal pessaries to induce sexual activity, blood samples were collected every 4 days from 16 ewe lambs aged 7 months, in order to determine the incidence of ovulations by measurement of plasma progesterone concentrations. It has been studied whether the response to a progestagen treatment of ewe lambs apparently close to puberty could be modified by the onset of the ovarian events preceding puberty. The effect of the presence or absence of ovulations prior to progestagen treatment on the potential reproductive performance (fertility, litter size and fecundity), embryo development [embryo quality and interferon-tau (IFNτ) secretion], luteal function (progesterone secretion in vitro ) and endometrial progesterone content was studied in seven ovulating (Ov+) and nine nonovulating ewe lambs (Ov−) on day 14 after mating. The best potential reproductive results were obtained with Ov+ animals, although these differences could not be initially attributed to either different progesterone secretion in vitro or concentration of endometrial progesterone. Irrespective of the experimental groups, secretion of progesterone by luteal tissue from ewe lambs with normal embryos was significantly greater (p<0.05) than that of animals with abnormal embryos or with no embryos. Normal embryos secreted a higher amount of IFN-τ than those embryos classified as abnormal (p<0.07). In conclusion, ewe lambs which exhibit luteal activity before puberty have the highest levels of reproductive performances after a progestagen treatment. Corpora lutea from ewe lambs with normal embryos had higher rates of progesterone secretion in vitro and their embryos had a higher IFN-τ production by the embryos, indicating greater capacity for subsequent development.  相似文献   
2.
Intracavitary Cisplatin Chemotherapy Experience with Six Dogs   总被引:1,自引:0,他引:1  
Six dogs with a median age of 7 years (range = 5-14 years) were presented for signs referable to thoracic or abdominal effusion associated with neoplasia of the body cavities. Intracavitary cisplatin was administered at 50 mg/m2 every 4 weeks for a median of 2.5 treatments (mean = 3, range = 1-6). Three dogs with pleural mesothelioma had complete resolution of effusion for 289, 129, and greater than 306 days without evidence of tumor growth. Resolution of effusion occurred after one treatment in two dogs and after two treatments in one dog. In three dogs with carcinomatosis of unknown origin, complete responses was seen in two dogs after one treatment for 255 and greater than 807 days, respectively. Intracavitary chemotherapy with cisplatin was associated with palliation and control of malignant pleural and/or abdominal effusion in five of six dogs. Toxicity was minimal, and this method of therapy should be further explored in dogs with similar malignancies.  相似文献   
3.
A study consisting of two trials was conducted to determine the effects of monensin on the apparent absorption and retention of magnesium (Mg), phosphorus (P), calcium (Ca) and zinc (Zn) and to determine mineral changes in tissue and ruminal fluid. Eight lambs (39 kg) were used in trial 1, and 10 lambs (37 kg) were used in trial 2. Animals were blocked by weight and fed a high concentrate diet with or without 20 mg/kg monensin. Trials began with a dietary adjustment period lasting 18 d in trial 1 and 21 d in trial 2. Animals were then placed in metabolism stalls for a 10-d stall adjustment period followed by a 12-d collection period. Collections to determine mineral balance were made during the first 10 d of the collection period. Blood and ruminal fluid samples were taken on d 11 of the collection period. Lambs were slaughtered on d 12 of the collection period and tissue samples were collected. Monensin supplementation increased (P less than .05) Mg retention 42.0%. Urinary Ca excretion decreased (P less than .05) 60.0% when monensin was fed. Monensin supplementation decreased (P less than .05) liver Ca and bone Ca, 45.5 and 2.9%, respectively. Apparent P digestibility increased (P less than .05) 40.0% and P retention increased (P less than .10) 26.8% due to monensin supplementation. Both apparent absorption and retention of Zn increased (P less than .01) 50.0 and 45.0%, respectively, with monensin supplementation. Ruminal fluid Zn concentrations decreased (P less than .05) 33.0% with the addition of monensin.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A stranded young pygmy sperm whale was nursed for four days in a pool, fed an artificial diet via a stomach tube and injected intramuscularly with antibiotics and corticosteroids. Initially unable to maintain her balance or to swim, she showed progressive improvement and by the third day could swim and dive quite strongly. Early on the fifth day her condition rapidly worsened and she died. An autopsy revealed extensive deep bruising in the head and mid-abdominal regions consistent with injuries sustained during the stranding.  相似文献   
6.
1. Four experiments were carried out on eggs from broiler breeding flocks between 26 and 60 weeks of age. The effects of storage and incubation conditions on hatchability were tested.

2. Collecting eggs hourly rather than five hours after lay slightly reduced hatchability (P<0.10). Pre‐storage fumigation of almost un‐contaminated eggs had no effect on hatchability even after storage for 8 d. Storing eggs in unsealed polythene bags did not affect hatchability of eggs stored for 5 or 8 d.

3. Eggs stored for 2 d hatched better when held at 18 °C than at 15 °C (P<0.05). Eggs stored for 8 d at 15 °C hatched better than eggs stored for 8 d at 18 °C (P< 0.01). Best hatchability was in eggs stored in unsealed polythene bags at a room temperature of 15 °C. When older eggs were allowed 30 to 40 min more in the setter for each day of storage, the decline in hatchability was 0.5 to 0.6 percentage units per day in storage as compared with a decline of 1.2 percentage units per day when eggs of different storage times, up to 8 d, were set simultaneously.

4. Those eggs which showed a weight loss during incubation of near average for their relative humidity (RH) treatment tended to hatch better than others except under conditions of very low RH (0.36), when best hatchability was associated with lower than average weight loss.

5. In eggs from a young flock (28 to 44 weeks of age) hatchability of fertile eggs was depressed by 1 percentage unit with an increase in RH of 0.17, and by 1 percentage unit with each decrease of 0.06 in RH from a control RH of 0.53. In eggs from the same flock between 48 and 60 weeks of age hatchability was depressed by 1 percentage unit with each 0.037 increase in RH from 0.44 to 0.70.

6. Eggs from a young flock (34–49 weeks) hatched significantly better when maintained at 0.82 rather than at 0.66 (P<0.05) or 0.95 (P<0.10) RH during the hatching period from 19 to 21 d of incubation. Eggs from an older flock (51–61 weeks) hatched better at 0.82 and at 0.‐92 than at 0.72 RH during the same period, but the differences were not significant.  相似文献   

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Objective To establish the prevalence of intussusceptions involving the caecum in a population of horses admitted to a university hospital for colic. Design Retrospective clinical study Methods Medical records of all horses admitted to the Massey University Veterinary Teaching Hospital between 1991 and 2004 were examined for information of those horses diagnosed with an intussusception involving the caecum. Results A total of 135 horses were admitted for colic surgery during the study period and 61 horses had a diagnosis of ileocaecal (37), caecocaecal (5) or caecocolic intussusception (19) made either at surgery or necropsy. Of the horses with ileocaecal intussusception, 32 had an incomplete hand-sewn ileocaecostomy without reduction and 29 survived to discharge. All the horses with caecocaecal intussusceptions were diagnosed preoperatively via rectal examination and/or transabdominal ultrasound: 2 were euthanased at surgery and 3 survived to discharge. In the 19 horses with caecocolic intussusceptions, manually reduction at surgery was performed in 6 and 5 of them survived to discharge. A typhlectomy was performed via a colotomy in 6 horses, 3 of which survived to discharge. Conclusions The high prevalence of intussusceptions involving the caecum seen at this referral centre may indicate a higher prevalence in New Zealand than is reported elsewhere in the world. Clinical relevance Intussusceptions involving the caecum should be considered as a differential diagnosis in horses presenting with chronic low-grade colic. Transabdominal ultrasound is useful for identifying caecocaecal and caecocolic intussusceptions. Hand-sewn side-to-side incomplete ileocaecostomy is a quick, effective and safe method of surgical treatment of ileocaecal intussusceptions.  相似文献   
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Two aborted Chester White pig fetuses were presented to a veterinary diagnostic laboratory in Illinois. Postmortem examination identified no gross abnormalities. Histologic evaluation revealed multifocal necrosis of chorionic epithelial cells, coalescing areas of mineralization in the placenta, and focal accumulations of viable and degenerate neutrophils in the lung. Intra- and extracellular acid-fast bacilli were identified in the lesions in both the placenta and lungs. Bacterial culture of stomach contents yielded heavy growth of Mycobacterium fortuitum, a rapidly growing nontuberculous mycobacterium (NTM), which was further confirmed through whole-genome sequencing. NTM are opportunistic pathogens commonly found in the soil and in contaminated water supplies. In animals, M. fortuitum is typically introduced through cutaneous wounds leading to infections limited to the skin, with systemic infection being uncommon. To our knowledge, abortion caused by M. fortuitum has not been reported previously.  相似文献   
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