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101.
The aim of this study was to asses the variation in the morphology of the seminal epithelium in relation to natural photoperiod in male cats. Tom cats (n = 240) were castrated every other week throughout the year. Each testis was fixed in Bouin's solution and cut into sections. The percentage of tubules with round spermatids (RS), elongated spermatids (ES), tailed spermatids (TS), mature spermatids (MS) and the number of Sertoli cells (SC) and Leydig cells (LC) were recorded in each sample. Testicles from males during short days (SHD) had a higher percentage of tubules with RS and ES compared to testicles from males during long days (LHD, 31.3 ± 0.6 vs 2.1 ± 0.6%, p < 0.001; 30.9 ± 0.7 vs 11.0 ± 0.7%, p < 0.001). Conversely, testicles from males during SHD had a lower percentage of tubules with TS and MS compared to testicles from males during LHD (24.5 ± 0.8 vs 29.7 ± 0.8%, p < 0.01; 13.1 ± 1.2 vs 57.0 ± 1.2%, p < 0.01). Furthermore, testicles from males during SHD had a higher number of SC and lower number of LC compared to testicles from males during LHD (11.4 ± 0.1 vs 8.0 ± 0.1%, p < 0.01; 19.2 ± 1.0 vs 38.0 ± 1.0%, p < 0.01). In conclusion, there are seasonal changes in testis cell morphology in the tom which may be related to seasonal sperm production.  相似文献   
102.
103.
Surgical ovariohysterectomy (OVH) using a right flank approach was performed in 114 bitches as part of the Animal Birth Control (ABC) Programme at Help in Suffering, Jaipur, India. Incision length, duration of surgery and postoperative pain scores were recorded for each animal. The mean weight of the bitches was 13.7 kg, and the mean body condition score was 4.5 on a 1-9 scale. Mean surgical incision length and time were 22 mm and 11 minutes 4 seconds, respectively. It was seen that 86.1 per cent of bitches required no additional postoperative analgesia. These findings compare favourably with other techniques for OVH, including laparoscopic techniques. The surgical approach described may be an alternative for canine OVH, particularly in a shelter setting.  相似文献   
104.
105.
SUMMARY Between 1967 and 1977 a study was made of diseases of cattle in the Solomon Islands. Tuberculosis was found in only 3 herds and was eradicated by 1975. Brucellosis serology revealed very few reactors and by 1977 the herds involved were considered free of the disease. Significant serological reactions were found to Leptospira interrogans serovars pomona, hardjo, autumnalis and jez-bratislava. There was evidence that infectious bovine rhinotracheitis and mucosal disease were present. Seventeen parasites were identified of which Haematobia irritans exigua, Haemonchus placei, Oesophagostomum radiatum and Ceylonocotyle streptocoelium were widely distributed. Nutritional stress occurred under some forms of husbandry but environmental stress was minimal. The Solomon Islands are therefore in a most favourable situation with regard to diseases of cattle.  相似文献   
106.
A series of case reports detailing observations on toxicity episodes in birds caused by a variety of agricultural chemicals and other substances is presented. These problems arose as a result of ignorance, accident and malicious intent. The episodes involved maldison, monocrotophos, fenitrothion, trichlorofon, dieldrin, chlordane, endrin, metaldehyde, bromadiolone, arsenic, lead and zinc. An unresolved episode where toxicity was implicated is also included.  相似文献   
107.
A group of 41 cats with signs of lower urinary tract disease was compared to a group of 41 cats without any history of disease for prevalence of seropositivity for feline immunodeficiency virus (FIV). The group of healthy cats was similar in age and gender to the group of cats with signs of lower urinary tract disease. Three of the cats with lower urinary tract disease and one control cat were seropositive for FIV.
This difference was not statistically significant. The most common cause of lower urinary tract signs was idiopathic. Only 7 cats had urinary tract infection, most associated with perineal urethrostomy or catheterization. Six of the cats with bacterial urinary tract infections were FIV negative. J Vet Intern Med 1996;10:34–38. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   
108.
1. In a 5 × 2 factorial experiment, the performance of male broiler chickens given starter (1 to 21 d) and finisher (21 to 42 d) diets containing five concentrations (0, 74.5, 149.0, 223.5 and 298.0 g/kg) of rapeseed meal (RSM) and two concentrations (0 and 15 g/kg) of polyethylene glycol (PEG) was measured.

2. Bodyweight gain and food intake decreased (P<0.01) with increasing dietary RSM both in the starter and finisher phases.

3. The relative weights of thyroid glands, liver, heart and the ratio of water to food intake increased (P<0.01) while the dressing percentage, abdominal fat‐pad weight and the feather condition score decreased (P<0.01) with increasing dietary RSM.

4. The mortality rate was increased (P<0.05) on diets containing 149 g/kg or more of RSM. The main causes of deaths and culling on the high RSM diets were enlarged livers and hearts, liver haemorrhage and leg disorders.

5. The inclusion of 15 g/kg PEG in the starter diets increased (P<0.01) bodyweight gains and food intake. It also increased (P<0.05) water consumption between 37–39 d, faecal moisture content at 40 d and the haemoglobin content in blood.

6. There were no interactions between the dietary concentrations of RSM and PEG on growth and other variables measured.  相似文献   

109.
The aims of the present study were to monitor the nucleolar cycle in Mongolian gerbil spermiogenesis, to verify the relationship between the nucleolar component and chromatoid body (CB) formation and to investigate the function of this cytoplasmic supramolecular structure in spermatogenic cells. Histological sections of adult seminiferous tubules were analysed cytochemically by light microscopy and ultrastructurally by transmission electron microscopy. The results reveal that in early spermatids, the CB was visualized in association with Golgi vesicles indicating that this structure may participate in the acrosome formation process as had been reported in other rodents. In late spermatids, the CB was observed near the axoneme region suggesting that this structure may support spermatozoon tail formation as happens in other species. Chromatoid body was joined with lipid droplets in this same cell type. This observation should be investigated to verify whether CB may be related to steroidal hormone metabolism. In conclusion, our data showed that there is disintegration of primary spermatocyte nucleoli at the beginning of prophase I and a fraction of this nucleolar material migrates to the cytoplasm, where a specific structure is formed, known as the ‘chromatoid body’, which apparently participates in some parts of the gerbil spermiogenesis process.  相似文献   
110.
The study evaluated, in early post‐partum anoestrous Nelore cows, if the increase in plasma oestradiol (E2) concentrations in the pre‐ovulatory period and/or progesterone priming (P4 priming) preceding ovulation, induced by hormonal treatment, reduces the endogenous release of prostaglandin PGF2αand prevents premature lysis of the corpus luteum (CL). Nelore cows were subjected to temporary calf removal for 48 h and divided into two groups: GPE/eCG group (n = 10) and GPG/eCG group (n = 10). Animals of the GPE/eCG group were treated with a GnRH agonist. Seven days later, they received 400 IU of eCG, immediately after PGF2α treatment, and on day 0, 1.0 mg of oestradiol benzoate (EB). Cows of the GPG/eCG group were similarly treated as those of the GPE/eCG group, except that EB was replaced with a second dose of GnRH. All animals were challenged with oxytocin (OT) 9, 12, 15 and 18 days after EB or GnRH administration and blood samples were collected before and 30 min after OT. Irrespective of the treatments, a decline in P4 concentration on day 18 was observed for cows without P4 priming. However, animals exposed to P4 priming, treated with EB maintained high P4 concentrations (8.8 ± 1.2 ng/ml), whereas there was a decline in P4 on day 18 (2.1 ± 1.0 ng/ml) for cows that received GnRH to induce ovulation (p < 0.01). Production of 13,14‐dihydro‐15‐keto prostaglandin F2α (PGFM) in response to OT increased between days 9 and 18 (p < 0.01), and this increase tended to be more evident in animals not exposed to P4 priming (p < 0.06). In conclusion, the increase in E2 during the pre‐ovulatory period was not effective in inhibiting PGFM release, which was lower in P4‐primed than in non‐primed animals. Treatment with EB promoted the maintenance of elevated P4 concentrations 18 days after ovulation in P4‐primed animals, indicating a possible beneficial effect of hormone protocols containing EB in animals with P4 priming.  相似文献   
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