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43.
Treatment with the synthetic glucocorticoid dexamethasone sodium phosphate increased the feed intake of sheep within 24 h. A single treatment with the longer-acting compound dexamethasone trimethylacetate had a slower effect, but resulted in improved feed intake and enhanced body weight gain over a period of 7 to 14 days. Treatment was effective in sheep housed individually and in sheep penned in groups. The improvement in body weight gain disappeared 15 to 20 days after a single treatment, but in most studies treated sheep had less variability in weight change than untreated sheep at this time. A statistically significant increase in body weight gain was observed in 8 of 11 trials; in the other 3 trials, it appeared that the feed intake of the untreated sheep was already maximal. Wethers treated with dexamethasone trimethylacetate on arrival at an assembly point for live export arrived in the Middle East 23 days later with a lower mean weight loss, partly because fewer sheep lost a significant amount of weight.  相似文献   
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The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ.  相似文献   
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In a study of some of the factors that are believed to affect fruit-setting in Eichhornia crassipes under Sudan conditions, the average number of flowers per inflorescence was twelve (range 4–26) while the average number of capsules per inflorescence was 1·5 (range 0–16). The problem of low fruit-setting was suggested to be basically due to the ecological factor of high temperature and low relative humidity. The flowers were preponderantly meso-stylic with the long and short-stylic ‘races’ absent or very rare. Recherches stir la biologic d'Eichhornia crassipes (Mart.) Solms dans le Nil Dans une étude sur quelques-uns des facteurs que l'on suppose actifs sur la mise à fruits de l’Eichhornia crassipes. dans les conditions du Soudan le nombre moyen de fleurs par inflorescence fut de 12 (s'étendent de 4 à 26), cependant que le nombre moyen de capsules par inflorescence fut de 1,5 (s'étendant de 0 à 16). Le probléme de la faible mise à fruit suggere qu'elle pourrait etre due a des facteurs écologiques: température élevée et faible humidity relative. Les fleurs étaient en majorité meso-stylées, les races à long style ou à style court étaient absentes ou tres rares. Generative Vermehrung von Eichhornia crassipes (Mart.) Solms. im Nil In einer Untersuchung über einige Faktoren, von denen angenommen wird, dass sie die Fruchtbildung von Eichhornia crassipes unter sudanesischen Bedingungen beeinflussen, war die durchschnittliche Anzahl von Blüten, 12 Blüten pro Inflorescenz (4–26), wáhrend die durchschnittliche Anzahl von Kapseln nur 1.5 Kapseln pro Inflorescenz war (0–16), Das Problem der geringen Fruchtausbildung wurde folgenden okologischen Faktoren zugeschrieben; hohe Temperatur und niedrige Luftfeuchtigkeit. Bei den Blüten wurden überwiegend Stempel miltlerer Länge gefunden, während die ‘Rassen’ kurzer und langer Stempel nicht oder nur sehr selten anzutreficn waren.  相似文献   
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AIM: To determine the impact of sodium molybdate treatment, given weekly, on concentrations of Cu in liver, activity of liver enzymes, and weight gain over 4 weeks, in yearling bulls with elevated concentrations of Cu in liver.

METHODS: The study was carried on two commercial grazing farms in the Otago region of New Zealand in yearling Friesian bulls (n=150 on Farm A and n=49 on Farm B) with mean concentration of Cu in liver >3,000 µmol/kg fresh weight. On Day 0, all animals were weighed and half were systematically allocated to treatment with sodium molybdate (3?mg/kg liveweight on Farm A and 7?mg/kg liveweight on Farm B); the remainder received no treatment (Control). Sodium molybdate was given as a drench weekly for 4 weeks and all animals were weighed again on Day 28. Ten animals on each farm (five from each treatment group) were systematically selected for blood sampling and liver biopsies on Days 0 and 28. Samples were analysed for concentrations of Cu in plasma, vitamin B12 in serum, activities of γ–glutamyl transferase, aspartate aminotransferase and glutamate dehydrogenase in serum, and concentrations of Cu and vitamin B12 in liver. Separate multivariable linear models were used to compare the change in outcome variables between Days 0 and 28 between bulls that had been drenched with sodium molybdate or not.

RESULTS: On Farm A, mean concentrations of Cu in liver on Day 28, as a percentage of concentrations on Day 0, for the control group was 55 (95% CI=40–73)% and for the treatment group was 73 (95% CI=43–111)%. On Farm B, the equivalent mean for the control group was 75 (95% CI=42–131)% and for the treatment group was 85 (95% CI=38–134)%. The multivariable linear models indicated that the changes in concentrations of Cu in liver, activities of liver enzymes and weight gain between Days 0 and 28 did not differ between the bulls treated or not with sodium molybdate (p>0.18).

CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with sodium molybdate in one bolus at weekly intervals for 4 weeks did not affect concentrations of Cu in liver, activity of liver enzymes or weight gain in animals with high concentrations of Cu liver on two farms.  相似文献   
48.
We have approached the problem of refrigerated storage of epididymal sperm samples from red deer by comparing three options: storing the genital (testicles within the scrotum), diluting the semen in extender or diluting the semen in extender supplemented with an anti-oxidant. Twenty-nine pairs of testes were collected. Spermatozoa from one of each of the pairs were immediately recovered, and diluted to 400 × 106 sperm/ml in Tris-citrate-fructose with 20% egg yolk. Control group was stored as such, and Anti-oxidant group was supplemented with 0.8 m m vitamin C. The remaining epididymides and the diluted samples were stored at 5°C and spermatozoa were analysed at 0, 24, 96 and 192 h for: motility [computer-assisted semen analysis (CASA)], acrosomal integrity, sperm viability (eosine/nigrosine staining), normal tails and chromatin status [sperm chromatin structure assay (SCSA)]. In general, seminal quality decreased with storage time. Vitamin C supported progressive motility better at 24 h (median 42% vs 23% Control and 15% epididymis), reduced the incidence of tail abnormalities and protected chromatin. Storing the semen in the epididymis slowed down motility loss, but slightly increased the occurrence of tail abnormalities and viability was lower at 192 h. However, regarding chromatin status, sperm stored in the epididymis was protected similarly to those diluted in the medium supplemented with vitamin C. Although the differences between the three groups were small, there were some advantages in supplementing the extender with vitamin C. Besides, refrigerating the epididymis may be a good option when immediate processing is not available.  相似文献   
49.
Imazapyr owes its importance in Morocco to its success in controlling the perennial weed Solanumelaeagnifolium Cav., which infests the Tadla area. Persistence and mobility of imazapyr has been studied in two Moroccan soils from the Rabat area, with differing organic matter content (red and organic soils), under laboratory conditions at 75% of their field capacities and 25–28 °C. Residue analysis was performed on the basis of a bioassay test using lentil (Lens culinaris Medic.) as indicator species. The residual activity of imazapyr accounted for 69%, 25%, 50% and 62%, 46%, 66% of the initial activity for the red and organic soils at 1, 5 and 10 mg L?1 respectively. The half-lives varied between 25 and 58 days for the red soil and 55 and 58 days for the organic soil. In the organic soil, imazapyr was highly mobile under the irrigation regime applied. Most of the activity was found in the first 3 × 75 mL of the effluents. A following biotest with the leached soil showed low remaining residual activity.  相似文献   
50.
Severe combined immunodeficiency disease (SCID) of horses is an autosomal, recessive hereditary disease occurring among Arabian or crossbred Arabian horses. The genetic defect responsible was previously identified as a 5‐base pair deletion in the gene encoding the catalytic subunit of the DNA dependant protein kinase (DNA‐PKcs). This study was carried out to determine the frequency of SCID and identify horses carrying the gene for SCID among Arabian and Arabian crossbred stallions and mares in Morocco using a DNA‐based test. Twenty‐one horses were SCID carriers: 14 (7%) Arabians, 6 (4%) Arab‐Barbs and one (3.3%) Anglo‐Arab. After analysing their genealogy, 3 imported stallions were identified that disseminated the mutant gene of DNA‐PKcs in Morocco.  相似文献   
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