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21.
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An in-office allergy screening kit was evaluated in 10 dogs that had no clinical signs of atopy but had various intestinal parasites. All 10 dogs had a positive reaction to the dust mite Dermatophagoïdes farinae, and four dogs had positive reactions to at least one other group of allergens. The kit as presently marketed gives numerous false positive results in parasitized nonatopic dogs.  相似文献   
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Two strains of bovine Theileria from northern Nigeria were shown to be identical to Theileria mutans in the indirect immunofluorescent antibody test. One of the strains was transmitted by the tick Amblyomma variegatum; large macroschizonts, typical for T mutans, could be demonstrated in infected cattle. It is concluded from these experiments and from the literature that there is reliable evidence so far for the occurrence in Nigeria of only two bovine Tehileria species, T mutans and T velifera.  相似文献   
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1. An experiment was done under commercial conditions to investigate the physiological effects of isolating broody turkey hens, for 72 h, in sand and wire floored pens on the third, 10th and 16th weeks of production.

2. Hens identified as broody and removed from the flock had higher plasma prolactin concentrations than the laying hens at each of the three experimental stages.

3. Confinement in sand and wire floored pens, induced a decline in plasma prolactin concentrations. This decline probably impeded immediate development of broody behaviour. Alternately, levels of prolactin higher than those of laying hens were again measured 7 and 14 days after treatment during third week but not after the 10 th and 16th week of production.

4. Confinement did not induce consistent changes in luteinising hormone (LH) and progesterone concentrations from one period to an other.

5. An increase in the plasma concentration of D‐(/?)‐hydroxybutyrate was observed in the hens which had an egg present in the oviduct on day 2, 3 and/or 4 of the treatment. Subsequently, a decrease in ovulation rate was observed in the hens with higher concentrations of D‐(β)‐hydroxybutyrate while under treatment, during the 10th week of production.

6. These data confirm that the effectiveness of the traditional methods for broodiness prevention under commercial conditions is related to the induction of a decrease of prolactin.  相似文献   

27.
Since the beginning of year 1987, the deer "Rusa" breeding has been developing in New Caledonia. In 1988, during a slaughter operation amidst the herds, nearly ninety blood samples were collected in order to define the blood biological parameters (or constants) of this species. Regarding haematology, the study concerns the following parameters: erythrocyte count (9.32 x 10(12)/l), leucocyte count (4.51 x 10(9)/l), various leucocyte lines and their formula, i.e. (neutrophile polymorphonuclear: 2.08 x 10(9)/l [46.6 p. 100]; lymphocytes: 1.75 x 10(9)/l [38.4 p. 100]; monocytes: 0.33 x 10(9)/l [7.5 p. 100]; eosinophiles polymorphonuclear leucocytes: 0.4 x 10(9)/l [7.46 p. 100]; basophile polymorphonuclear leucocytes: 0.01 x 10(9)/l [0.28 p. 100]), hematocrite (36.8 l/l), hemoglobin ratio (14.1 g/dl), mean corpuscular volume (40.3 dl), mean corpuscular hemoglobin rate (15.3 pg/cell), mean corpuscular hemoglobin concentration (38.7 g/dl). In the course of the study, variations of these parameters were detected according to various physiological criteria and to the sampling conditions as deer is a stress sensitive animal.  相似文献   
28.
The effect of true milk use in the diet of Spanish Brown Swiss male calves on animal performance, carcass and meat quality, and fatty acids composition was studied. In experiment 1, the effect of milk intake [ad libitum continuous (ADLIB) feed vs. restricted 0.7 during 75 days followed by ad libitum feed (RESTR)] and slaughter endpoint (225 kg vs. 5 month) were studied. In experiment 2, ad libitum concentrate feeding [grain-fed (GF)] was compared with milk supplementation until slaughter [milk-fed (MF)] in calves slaughtered at 345 kg. As regards to milk intake, carcass weight and degree of fatness were higher in the ADLIB group (P<0.05). The RESTR group revealed a higher percentage of saturated fatty acids (P<0.05). In experiment 2, the MF group exhibited a higher fat percentage (P<0.05), lower press and cooking losses (P<0.05), and higher scores for tenderness and juiciness (P<0.05) than the GF group. The percentage of saturated fatty acids was higher in the MF group (P<0.05). The results suggest that true milk use in veal production could be an advantageous alternative in terms on production costs, animal performance, and carcass and meat quality.  相似文献   
29.
Hormonal asynchronies during oestrus, related to the presence of suprabasal plasma-progesterone (P4) concentrations and a delayed ovulation, interfere with the fertility of repeat-breeder heifers (RBH). Since tubal dysfunction can occur in connection with hormonal asynchronies and constrained availability of fertile spermatozoa at the time of ovulation, the present study tested the hypothesis that frequent sperm deposition from onset of oestrus to ovulation may improve pregnancy rates in RBH. Five RBH and five virgin heifers (VH; controls) were repeatedly artificially inseminated (AI) at 6 h intervals from onset of oestrus to spontaneous ovulation. Hormone analyses revealed suprabasal P4 concentrations and a delay in the occurrence of the luteinising hormone (LH) surge, but a normal cortisol profile in RBH. Compared with controls, RBH presented longer interval from onset of oestrus to ovulation, and therefore, received more AIs. Pregnancy rates in RBH reached control levels (60%; NS), indicating that the hypothesis might be correct. Pregnancy rates in VH were below the expected range, presumably attributed to a deleterious influence of the frequent handling. The study suggests that pregnancy rates can be improved in RBH by frequent AI in relation to spontaneous ovulation. However, this practice of repeated manipulations, while seeming not to show adverse effects, lacks practicality for routine use.  相似文献   
30.
Basic principles of surgery are important to review, even for experienced surgeons. Although aseptic surgical principles are not always applicable in the field, we have to respect some guidelines. Recent research will influence the way that we do things, based on what we have been taught and our experience. Respecting those simple principles can make a big difference in the final outcome.  相似文献   
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