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71.
The introduction of mechanised harvesting often results in a redesign of the crop canopy. Computer models have been used to predict light interception, and hence potential yield, by a range of hedgerow tree forms and spacings as a guide to the design of orchard systems for mechanical harvesting. Light interception is increased by increasing tree height, thickness and leaf-area density, and by reducing the clear alleyway. Narrow hedgerows less than 2 m high will need straddle harvesting to avoid loss of light interception and yield. 相似文献
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Serological study of leptospiral infections and endogenous uveitis among horses and ponies in the United Kingdom 总被引:1,自引:0,他引:1
The prevalence of antibody titres to a range of 20 leptospira antigens in the serum of horses and ponies with no ophthalmic abnormalities and with ophthalmoscopic evidence of endogenous uveal inflammatory disease was determined using a microscopic agglutination technique. Titres against leptospira antigens were observed in 13 out of 138 (9.1 per cent) animals with no ophthalmic abnormalities, and in three out of 27 (11.1 per cent) animals with anterior uveitis. Serovar sejroe was common to all seropositive animals with anterior uveitis. The results show that leptospira infection is not a major factor in the aetiology of equine anterior uveitis in the UK, but suggests that the organism may be associated with some cases of recurrent anterior uveitis. 相似文献
75.
A preliminary investigation of the blood levels of carbenicillin, after the administration of a single intramuscular injection, suggests that the tortoise's bladder may act as a reservoir of antibiotic that is available for resorption. This phenomenon could confound the establishment of a safe, effective dose regime for antibiotics, in tortoises, which are excreted in an unchanged active form in urine. 相似文献
76.
Equine ehrlichial colitis (Potomac horse fever): recognition of the disease in Pennsylvania, New Jersey, New York, Ohio, Idaho, and Connecticut 总被引:5,自引:0,他引:5
J E Palmer R H Whitlock C E Benson 《Journal of the American Veterinary Medical Association》1986,189(2):197-199
Equine ehrlichial colitis (Potomac horse fever), a newly identified colitis of the horse, was first recognized in Maryland. In this report, we document occurrence of the disease in Pennsylvania, New Jersey, New York, Ohio, Idaho, and Connecticut. Enzootic areas were recognized by a characteristic pattern. Frequently there was a seasonal pattern and high prevalence of sporadic colitis in unstressed horses. The attack rate per farm generally was low. Horses on pasture, as well as those stabled, were affected. Clinical signs varied from fever and depression to severe diarrhea and laminitis. Occasionally horses developed profound ileus and severe colic. Diagnosis was based on detection of an increase or decrease in serum antibody titers to Ehrlichia risticii, using an indirect fluorescent antibody technique. 相似文献
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TF. JUBB P. BRIGHTLING J. MALMO† MT. LARCOMBE GA. ANDERSON SJ. HIDES‡ 《Australian veterinary journal》1989,66(10):334-336
Anoestrous dairy cows in seasonally calving herds in the Macalister Irrigation District of Gippsland, Victoria were treated at the start of the mating period with a progesterone releasing intravaginal device (CIDR). The CIDR was inserted for 7 days and 400 IU of PMSG was injected intramuscularly at removal. There was no clinically useful difference among cows receiving the CIDR, a placebo and untreated cows in the interval from treatment to either first oestrus or conception, the conception rate to first service or percent pregnant by the end of mating. Analyses of data from 2-year-old cows, older cattle, cows calved at least 45 days or cows calved at least 55 days and cows treated 3 weeks after the start of mating did not show improved reproductive performance following treatment with the CIDR. 相似文献
79.
The concentrations of several post mortem aqueous humour chemical constituents were compared with ante mortem serum chemical values in the horse. Urea nitrogen and creatinine values in post mortem aqueous humour were good predictors of ante mortem serum values. Aqueous humour urea nitrogen increased only slightly and creatinine did not change significantly for up to 24 h after death. Formulae were derived for calculating estimated ante mortem serum urea nitrogen and creatinine from aqueous humour values obtained after death. These results from normal horses identify analytes that are accurate predictors of ante mortem serum values. Determination of post mortem aqueous humour urea nitrogen of creatinine may assist in interpretation of the functional significance of equivocal histological lesions in the kidney. 相似文献
80.