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11.
The association between lameness and fertility in dairy cows   总被引:1,自引:0,他引:1  
One thousand, four hundred and ninety-one lactations in 770 Friesian, Holstein and Ayrshire crossbred cows have been used to study the associations between lameness and fertility. Lameness was associated with a longer interval between calving and first service and a longer interval between calving and conception. The largest increases in these intervals, of 17 and 30 days, respectively, occurred in cows with either sole or white line lesions occurring between 36 and 70 days after calving. The conception rate during the 63 days before a diagnosis of lameness was made was lower (31 per cent) than at other times (40 per cent).  相似文献   
12.
COSREEL, a computerised animal health recording system with a versatile coding system for recording diagnoses, symptoms and medical and surgical treatments, has been tested by veterinary surgeons in practice. The codes were found to be logical and generally easy to use. The application of these codes, with particular reference to their use in infertility investigations, is illustrated.  相似文献   
13.
Formic, acetic, or n-propionic acid applied with fenitrothion to Tribolium castaneum, inhibited the production of both fenitroxon and O-desmethyl fenitrothion, but did not appear to affect metabolic attack on the P-O-phenyl link. These effects are comparable to those of some pyrethrum synergists. The toxicity of fenitrothion was synergised by formic or acetic acid, and antagonised by propionic acid, but these effects on potency were slight.  相似文献   
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Debris flows have deposited inorganic laminae in an alpine lake that is 75 kilometers east of the Pacific Ocean, in Ecuador. These storm-induced events were dated by radiocarbon, and the age of laminae that are less than 200 years old matches the historic record of El Nino events. From about 15,000 to about 7000 calendar years before the present, the periodicity of clastic deposition is greater than or equal to 15 years; thereafter, there is a progressive increase in frequency to periodicities of 2 to 8.5 years. This is the modern El Nino periodicity, which was established about 5000 calendar years before the present. This may reflect the onset of a steeper zonal sea surface temperature gradient, which was driven by enhanced trade winds.  相似文献   
16.
Objective : To identify the optimal method of submission of canine and feline urine for bacterial culture. Methods : Cystocentesis samples from 250 animals (200 dogs, 50 cats) suspected of having urinary tract infections were collected. The reference aliquot, without preservative, was processed on site within 2 hours. Two further aliquots (one without preservative, one with boric acid) were stored at room temperature for up to 7 hours and then posted by guaranteed next day delivery to a commercial laboratory for analysis. Results : Forty‐seven of the samples were positive on culture in the reference test. There was no significant difference between reference test results and those of samples posted without preservative (P=0·39), but samples posted in boric acid were significantly less likely to give a positive result (P=0·01). Samples posted without preservative had a sensitivity of 82% and a specificity of 98%; for boric acid, sensitivity was 73% and specificity 99%. Clinical Significance : Postal urine samples should be submitted to the laboratory in a plain sterile tube.  相似文献   
17.
The practice of'early bite' was surveyed on sixty dairy farms in Wales during the period 1958–60. Assessment in a financial sense was made of the pros and cons of this practice. It was obvious that'early bite' was wasted or misused on many farms.  相似文献   
18.
Groups of eight Welsh Mountain sheep were dosed with diamphenethide at the rate of 70 mg/kg bodyweight at either one, four, six or eight weeks after artificial infection with approximately 300 Fasciola hepatica metacercariae. Comparisons were made with similarly infected but undosed sheep and with sheep which were neither infected nor dosed. The good clearance of flukes up to six weeks of age (above 97 per cent on pooled data) was reflected in the plasma concentrations of the accepted liver damage marker enzymes glutamate dehydrogenase and gamma-glutamyl transpeptidase. Highly significant correlations were demonstrated between the numbers of flukes recovered, the plasma levels of these enzymes and haemoglobin and plasma albumin values. At 70 mg/kg, diamphenethide was shown to be able to control F hepatica populations of up to six weeks of age. The systematic use of diamphenethide at this dose level at intervals of up to six weeks during the period of metacercarial challenge should prevent ovine fascioliasis.  相似文献   
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The occurrence of vesicular follicles and corpora lutea (CL), without evidence of ovulation, in late fetuses and during prepubertal life was confirmed in the southern giraffe. In this, and other respects, the pattern of ovarian development is similar in the southern giraffe to the northern subspecies. This early ovarian activity recedes during late prepubertal life. Numerous accessory CL were present in pregnant and non-pregnant giraffe but they did not attain the size of the true CL of pregnancy. The latter undergo an initial phase of rapid enlargement lasting about 100 days, followed by a period of recession till mid-pregnancy and a second growth phase which persists until term (457 days). The CL of pregnancy rapidly regresses after parturition. The accessory CL regress slowly and form normal looking corpora albicantia (CA). These CA are most abundant during early adult life as also are vesicular follicles.  相似文献   
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