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1.
SUMMARY: Vascular access ports were surgically placed, first in rabbits maintained under laboratory conditions, and then in koalas maintained in a wildlife park. The ports remained patent for 9 months in rabbits and for up to 13 months in the koalas and were removed successfully. They allowed collection of blood samples without assistance or disturbance in koalas, and without stress as reflected by plasma cortisol concentration. The use of retention rings on the cannula tubing is recommended. 相似文献
2.
Aly KAREN árpád Csaba BAJCSY Rosa MINOIA Rezs? KOVáCS Noelita Melo DE SOUSA Jean-Fran?ois BECKERS János TIBOLD István MáDL Ottó SZENCI 《The Journal of reproduction and development》2014,60(2):162-167
The aim of the present study was to determine the relationship of progesterone (P4),
bovine pregnancy-associated glycoprotein-1 (bPAG-1) and nitric oxide (NO) levels with late
embryonic (LEM; day 28 to day 42) and early fetal mortalities (EFM; > day 42 to day 56)
in dairy cows. Transrectal ultrasonography (6–8 MHz) was performed in 100
Holstein-Friesian cows at days 28, 42 and 56 after artificial insemination (AI; day 0) to
diagnose pregnancy and to monitor the fate of the embryo. After ultrasound scanning of
each cow, a milk sample was collected for assessment of P4 by an ELISA test and a blood
sample was collected for assessment of bPAG-1, by using a double-antibody
radioimmunoassay, and serum NO metabolites (nitrate + nitrite). Based on ultrasonographic
examinations and bPAG-1-RIA, 41 of 100 inseminated cows were confirmed pregnant at day 28
after AI. Nine cows suffered of LEM, and 6 cows suffered of EFM and the overall pregnancy
loss rate was 36.6% (15/41) between days 28 and 56 of pregnancy. By logistic regression
analysis, there were no significant relationships between the level of P4 and bPAG-1 at
day 28 after AI and the occurrence of LEM and EFM. Also, there were no significant
relationships between the levels of P4 and bPAG-1 at day 42 and the occurrence of EFM. On
the other hand, a significant relationship (P<0.05) was found between NO level at day
28 and the occurrence of LEM. In conclusion, measurement of the serum NO concentration at
day 28 of pregnancy might help to predict the outcome of pregnancy by day 42 in dairy cows
but further studies are needed to confirm this. 相似文献
3.
Summary Various cardiorespiratory and metabolic indices were assessed during treadmill exercise in Thoroughbred and Standardbred racehorses with T wave changes in 4 or more leads on the electrocardiogram or second-degree atrio-ventricular (AV) block, and in horses that had no abnormalities on clinical examination, resting electrocardiography or upper respiratory tract endoscopy. No significant differences in heart rate, plasma lactate concentration, arterial blood gases, oxygen uptake, run time, peak velocity, or blood and red cell volumes were found between normal horses and horses with T wave changes or second-degree AV block. These results indicate that some electrocardiographic findings that are considered by some clinicians to indicate cardiac dysfunction, may have little effect on exercise capacity. 相似文献
4.
SUMMARY Twenty-five Thoroughbred (TB) and 25 Standardbred (SB) stables were visited to determine their feeding practices. The ingredients of the main feed of the day for a mature gelding of average size in full training were weighed at each stable. Nutrient content of diets was calculated using published data for the individual ingredients. Results are expressed as mean±sd. The estimated body weight of TB horses was 493±34 kg and 437±32 kg for SB horses. There was considerable variation in diet composition and nutrient intake between stables. The TB trainers fed 11.0±2.4 kg and SB trainers 11.8±2.5 kg per day. The concentrate component of the diet weighed 7.8±1.6 and 7.7±2.3 kg for TB and SB stables, respectively, and the roughage component for TB horses 3.3±1.4 and SB horses 4.1±1.4 kg per day. The digestible energy intake of horses at TB stables was 129±29 MJ per day and at SB stables 132±31 MJ per day. Crude protein intake of TB horses was 1452±363 g and SB horses 1442±338 g per day. There were differences in some feeding practices at TB and SB stables. Standardbred trainers fed more roughage than TB trainers. Standardbred trainers fed chaffed lucerne (alfalfa) and cereal hays as the major roughage, whereas TB trainers fed more hay. The major hay type fed by TB trainers was lucerne, whereas many SB trainers preferred clover hay. Both trainers fed oats as the major grain, but TB trainers fed slightly more maize (corn) than SB trainers. The SB trainers fed barley as part of the concentrate component of the diet, whereas TB trainers usually fed boiled barley and linseed oil in winter only. Although many trainers used vitamin and mineral supplements, this appeared unnecessary in many Instances, especially with respect to Iron. Calcium and NaCI supplementation was necessary for some diets. We concluded that while there was a wide range in feed intake and diet composition for both TB and SB horses, average nutrient intakes were similar to National Research Council (1989) recommendations for horses performing intense work. 相似文献
5.
6.
Field trial of a staphylococcal mastitis vaccine in dairy herds: clinical, subclinical and microbiological assessments 总被引:4,自引:0,他引:4
Objective To assess the efficacy of a new staphylococcal mastitis vaccine under commercial dairying conditions.
Design A field trial involving 1819 cows and heifers conducted on seven dairy herds in Victoria. The trial was done 'blind'; approximately half the animals were vaccinated and the remainder were untreated controls.
Procedure The vaccine was given twice during the last 10 weeks of pregnancy. Effects of vaccination were assessed, during the ensuing lactation, on the basis of clinical and sub-clinical mastitis and microbiological investigations of the milk.
Results A total of 273 cases of clinical mastitis were recorded. Staphylococcus aureus was isolated from 112 of these, 45 cases in vaccinates and 67 cases in controls; the difference was not statistically significant. One herd was notable in having a high incidence of clinical staphylococcal mastitis. This herd accounted for 15.8% of the animals in the field trial but 54.5% of cases of clinical staphylococcal mastitis. For this herd, vaccinated animals had significantly lower incidence of clinical staphylococcal mastitis and prevalence of subclinical mastitis, relative to controls. An unexpected feature of the trial as a whole was the low incidence of clinical mastitis from which S aureus was isolated in pure culture (26.3% of cases) and the high incidence of clinical Streptococcus uberis mastitis (22.7% of cases).
Conclusions The trial showed that the vaccine was efficacious in reducing the incidence of clinical mastitis and prevalence of subclinical mastitis in a herd that had a serious staphylococcal mastitis problem. 相似文献
Design A field trial involving 1819 cows and heifers conducted on seven dairy herds in Victoria. The trial was done 'blind'; approximately half the animals were vaccinated and the remainder were untreated controls.
Procedure The vaccine was given twice during the last 10 weeks of pregnancy. Effects of vaccination were assessed, during the ensuing lactation, on the basis of clinical and sub-clinical mastitis and microbiological investigations of the milk.
Results A total of 273 cases of clinical mastitis were recorded. Staphylococcus aureus was isolated from 112 of these, 45 cases in vaccinates and 67 cases in controls; the difference was not statistically significant. One herd was notable in having a high incidence of clinical staphylococcal mastitis. This herd accounted for 15.8% of the animals in the field trial but 54.5% of cases of clinical staphylococcal mastitis. For this herd, vaccinated animals had significantly lower incidence of clinical staphylococcal mastitis and prevalence of subclinical mastitis, relative to controls. An unexpected feature of the trial as a whole was the low incidence of clinical mastitis from which S aureus was isolated in pure culture (26.3% of cases) and the high incidence of clinical Streptococcus uberis mastitis (22.7% of cases).
Conclusions The trial showed that the vaccine was efficacious in reducing the incidence of clinical mastitis and prevalence of subclinical mastitis in a herd that had a serious staphylococcal mastitis problem. 相似文献
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9.
KR Arrigo DL Worthen MP Lizotte P Dixon G Dieckmann 《Science (New York, N.Y.)》1997,276(5311):394-397
A numerical model shows that in Antarctic sea ice, increased flooding in regions with thick snow cover enhances primary production in the infiltration (surface) layer. Productivity in the freeboard (sea level) layer is also determined by sea ice porosity, which varies with temperature. Spatial and temporal variation in snow thickness and the proportion of first-year ice thus determine regional differences in sea ice primary production. Model results show that of the 40 teragrams of carbon produced annually in the Antarctic ice pack, 75 percent was associated with first-year ice and nearly 50 percent was produced in the Weddell Sea. 相似文献
10.
HARRIS CS 《Science (New York, N.Y.)》1963,140(3568):812-813
After seeing his hand through wedge prisms, a subject points incorrectly with that hand at auditory as well as visual targets. The other hand is virtually unaffected. Thus the change cannot be solely visuo-motor or visual. Other evidence suggests that it is a change in felt hand location, rather than motor learning. When the subject's adapted hand feels as if it is pointing straight ahead, for example, it is actually pointing off to one side. 相似文献