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911.
912.
A gas chromatographic method for the determination of 2,3,7,8-tetrachloro-dibenzo-1,4-dioxin in 2,4,5-trichlorophenoxyacetic acid and 2,4,5-T alkyl ester herbicides is described. Of 80 samples of 100% 2,4,5-trichlorophenoxyacetic acid alkyl ester herbicides 25 contained less than 0.05 part/million and 75 less than 0.5 part/million 2,3,7,8-tetrachlDrodiben2o-1,4-dioxin. Of 32 samples of 50% formulations of 2,4,5-T alkyl esters in mineral oil, 8 contained less than 0.05 part/million and 18 less than 0.5 part/million tetrachlorodioxin. The maximum found was 28.3 part/ million.  相似文献   
913.
Hardness of bovine hoof horn was tested as ball indentation hardness and as shore D hardness post mortem in different segments of the hoof wall, in the sole and the hard bulb of sound claws of 10 Austrian Holstein Friesian cows. Both methods of hardness determination showed corresponding results, with shore D hardness between 52.2 and 63.9 hardness units (hu) and ball indentation hardness between 11.2 N/mm2 and 24.3 N/mm2. Bovine hoof horn becomes significantly softer from the coronary band towards the weight bearing border (vertical decrease) and from the dorsal wall towards the heel (horizontal decrease). Decreasing hardness was associated with decreasing dry matter content. Measurements of the claw capsule showed thickness of the hoof wall increasing from the coronary border towards the sole. In dorsopalmar/-plantar direction, bovine hoof wall at the weight bearing border decreases towards the heel.  相似文献   
914.
Fourichon C  Beaudeau F  Bareille N  Seegers H 《Preventive veterinary medicine》2005,72(1-2):177-81; discussion 215-9
Production losses and treatment expenditures consecutive to bovine viral diarrhoea virus (BVDV) infection in a dairy herd were calculated by partial budgeting based on published estimates of production effects. Overall costs (losses plus expenditures) resulted in a decreased gross margin of 10.7 euros and 19.0 per 1000 l of milk for an average and severe infection, respectively. With a milk quota system allowing no lease of quota, assuming adjustment of the herd size by the farmer to produce the quota, decrease in gross margin was limited to 7.9 euros and 13.9 per 1000 l of milk.  相似文献   
915.
Two Syrian hamsters developed marked swelling of the ventral neck. Histologic examination of both masses revealed that the submaxillary salivary glands were effaced by large numbers of neoplastic plasma cells. In one hamster, neoplastic cells had infiltrated the adjacent lymph node. The neoplastic cells expressed CD79a antigen and were negative for CD3, lambda, and kappa light chains. Ultrastructural features of neoplastic cells in the salivary gland of one hamster included abundant cytoplasmic rough endoplasmic reticulum profiles, and peripherally displaced nuclei that contained marginated heterochromatin, consistent with plasma cells. Salivary gland plasmacytomas are extremely rare in humans and have not previously been reported in nonhuman species. The occurrence of such neoplasms in two hamsters suggests that this species may be predisposed to developing tumors of this type.  相似文献   
916.
OBJECTIVE: To determine sedative and cardiorespiratory effects of romifidine alone and romifidine in combination with butorphanol and effects of preemptive atropine administration in cats sedated with romifidine-butorphanol. DESIGN: Randomized crossover study. ANIMALS: 6 healthy adult cats. PROCEDURES: Cats were given saline (0.9% NaCl) solution followed by romifidine alone (100 microg/kg [45.4 microg/lb], i.m.), saline solution followed by a combination of romifidine (40 microg/kg [18.1 microg/lb], i.m.) and butorphanol (0.2 mg/kg [0.09 mg/lb], i.m.), or atropine (0.04 mg/kg [0.02 mg/lb], s.c.) followed by romifidine (40 microg/kg, i.m.) and butorphanol (0.2 mg/kg, i.m.). Treatments were administered in random order, with > or = 1 week between treatments. Physiologic variables were determined before and after drug administration. Time to recumbency, duration of recumbency, time to recover from sedation, and subjective evaluation of sedation, muscle relaxation, and analgesia were assessed. RESULTS: Bradycardia developed in all cats that received saline solution and romifidine-butorphanol or romifidine alone. Preemptive administration of atropine prevented bradycardia for 50 minutes in cats given romifidine-butorphanol. Oxyhemoglobin saturation was significantly decreased 10 minutes after romifidine-butorphanol administration in atropine-treated cats. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that administration of romifidine alone or romifidine-butorphanol causes a significant decrease in heart rate and that preemptive administration of atropine in cats sedated with romifidine-butorphanol effectively prevents bradycardia for 50 minutes.  相似文献   
917.
A 5-yr-old female African hedgehog (Ateleris albiventris) presented with hematuria. Vulvar culture results revealed a 4+ growth of Enterococcus sp. and gamma-Streptococcus sp. susceptible to trimethoprim sulfa and enrofloxacin. Ultrasound evaluation of the abdomen revealed an unidentifiable tubular structure in the region of the reproductive tract. An exploratory laparotomy and ovariohysterectomy were performed. Pathologic studies of the uterus showed a uterine spindle cell tumor, uterine endometrial polyp, uterine adenomyosis, and a possible acute infarct resulting in uterine wall necrosis. Hematuria did not reoccur, and the hedgehog lived for another 19 mo until she died from an oral squamous cell carcinoma. To date, this is the first report of a uterine spindle cell tumor in an African hedgehog.  相似文献   
918.
Livestock production and ruminants in particular are an integral part of the organic mixed farming concept. In this paper, the feeding patterns of 26 organic dairy farms in two different regions in Germany are analysed, with particular emphasis on the amount and proportion of concentrates and purchased feed related to the dairy performance expressed per cow and hectare. Calculated on an energy basis (MJ NEL), the annual average milk yield of 6737 kg cow− 1 is derived from roughage (74%), concentrates and cobs (23%), and commercial processing by-products (e.g., spent grains) (3%). Per cow and year, 937 kg dry matter (DM) (range: 0–2724 kg) of concentrates are fed with an intensity of 135 g kg− 1 milk (range: 0–378 g kg− 1). Approximately 65% of the concentrates and commercial processing by-products are purchased. The area-related milk yield is almost 7000 kg ha− 1. For fodder production, 0.96 ha per cow is needed, of which 0.85 ha is farm land. The equivalent production area for purchased fodder is 0.11 ha. In the analysed region in northwestern Germany, most correlations between milk yield and analysed feeding parameters are close and significant. This is in contrast to the region in the south, where the variability of amount and proportion of the different feed types is predominantly independent of the milk yield. Intensification of dairy production to increase milk performance using a higher proportion of concentrates and purchased feed at some of the analysed farms needs to be carefully assessed according to the organic farming profile.  相似文献   
919.
The present study explores the welfare aspects of involuntary milking in dairy herds with an automatic milking system (AMS) as it focuses on whether fetching of cows for milking may be related to fear/discomfort of the automatic milking unit (AMU) or the milking itself and further, may strain the human–animal relationship. Behavioural data on cow reluctance when entering the AMU, stepping and kicking behaviour during milking and avoidance of humans was collected at 6 two-day visits to 8 Danish commercial AMS herds during a year. The data set for the analysis included one observation per cow of reluctance when entering the AMU and behaviour during milking of a total of 869 cows; 255 cows fetched for milking and 614 non-fetched cows. For 82 of the cows fetched for milking and for 370 of the non-fetched cows the data further included one observation per cow of avoidance towards an approaching unfamiliar human in a test situation. Multivariate analyses by conditional hierarchical log-linear models showed that fetchings were more frequent the first 14 days of lactation (P < 0.001). The multivariate analysis showed no associations between fetching and reluctance at entering the AMU, nor an association to stepping and kicking during milking. However, compared to non-fetched cows, fetched cows were more frequently avoiding the test person in the human approach test (P < 0.001). It is concluded that fetching may strain the human–animal relationship.  相似文献   
920.
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