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91.
Cesar A. Rosales Nieto Mark B. Ferguson Jan R. Briegel Mark P. Hedger Graeme B. Martin Andrew N. Thompson 《Reproduction in domestic animals》2019,54(12):1596-1603
Metabolic homeostasis is aligned with changes in growth and body composition, through processes mediated by circulating metabolites and metabolic hormones, and is eventually linked to reproductive success. In the present study with sheep, we determined the relationships among phenotypic and genotypic rates of growth, muscle and fat accumulation, and the circulating concentrations of metabolic and tested for relationships with the timing of puberty and subsequent reproductive outcomes. We used 64 females and 62 males with known phenotypic values for depth of eye muscle (EMD) and fat (FAT) and known Australian Sheep Breeding Values at post‐weaning age for live weight (PWT), depth of eye muscle (PEMD) and depth of fat (PFAT). Blood plasma sampled every 20 min for 8 hr via was assayed for growth hormone (GH), insulin‐like growth factor I (IGF‐I), insulin, leptin, ghrelin, follistatin, glucose and non‐esterified fatty acids (NEFA). In males, PWT was positively related to the concentrations of GH, follistatin and glucose, whereas FAT and PFAT were positively related to IGF‐I concentrations (p < .01). Testosterone concentration was negatively related to muscle variables (p < .001) and to PFAT (p < .05). In females, the only significant relationship detected was the positive link between EMD and insulin concentrations (p < .05). Reproductive variables were only measured in females. Live weight at first oestrus was related positively to insulin concentration and negatively to GH concentration (p < .05). No other relationships with reproductive variables were significant. The relationships that were detected suggest subtle differences between the sexes in the way their metabolic homeostasis responds to changes in the rates of growth, and muscle and fat accumulation, perhaps due to interference by testosterone in the males. 相似文献
92.
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
93.
Farrell A Thirugnanam S Lorestani A Dvorin JD Eidell KP Ferguson DJ Anderson-White BR Duraisingh MT Marth GT Gubbels MJ 《Science (New York, N.Y.)》2012,335(6065):218-221
Exocytosis is essential to the lytic cycle of apicomplexan parasites and required for the pathogenesis of toxoplasmosis and malaria. DOC2 proteins recruit the membrane fusion machinery required for exocytosis in a Ca(2+)-dependent fashion. Here, the phenotype of a Toxoplasma gondii conditional mutant impaired in host cell invasion and egress was pinpointed to a defect in secretion of the micronemes, an apicomplexan-specific organelle that contains adhesion proteins. Whole-genome sequencing identified the etiological point mutation in TgDOC2.1. A conditional allele of the orthologous gene engineered into Plasmodium falciparum was also defective in microneme secretion. However, the major effect was on invasion, suggesting that microneme secretion is dispensable for Plasmodium egress. 相似文献
94.
H. P. Kulembeka M. Ferguson L. Herselman E. Kanju G. Mkamilo E. Masumba M. Fregene M. T. Labuschagne 《Euphytica》2012,187(2):277-288
Cassava brown streak disease (CBSD) is an economically important virus disease causing significant losses to cassava root yield and quality in east, central and southern Africa. Breeding for resistance in cassava requires an understanding of the underlying genetic control of CBSD resistance. Sources of CBSD resistance are available but little is known on the value of those varieties as parents for CBSD resistance breeding. Two resistant and two susceptible varieties were crossed in a half diallel design and 35 F1 progeny from each of the six families, plus parents, were screened at two locations in a randomised complete block design with four replications in warm sub-humid environments of coastal Tanzania in 2008. Screening for CBSD field resistance was done using disease severity scoring on a scale of 1–5. Significant variations in disease severity were observed for crosses, general combining ability (GCA) and specific combining ability (SCA) at both locations. The CBSD shoot symptom severity scores ranged from 1 to 4.4 while root necrosis ranged from 1.3 to 4.5. The contribution of GCA to the total sum of squares of crosses for disease scores ranged from 86.9 to 95.2 % compared to SCA that ranged from 4.8 to 14.2 %. Additive gene effects were more important than non-additive effects indicating that CBSD resistance is genetically determined and that selection should be successful to improve resistance. Selection of parents with good GCA effects will be important for success in CBSD resistance breeding. 相似文献
95.
96.
Walsh PJ Remedios AM Ferguson JF Walker DD Cantwell S Duke T 《Veterinary surgery : VS》1999,28(6):472-479
OBJECTIVE: To evaluate postoperative pain and morbidity in dogs undergoing open thoracotomy and partial pericardectomy versus thoracoscopic pericardectomy. STUDY DESIGN: Research study in normal dogs. ANIMALS OR SAMPLE POPULATION: Fourteen mixed breed healthy dogs. METHODS: Seven dogs had a partial pericardectomy through a standard left lateral thoracotomy at the fifth intercostal space. The remaining seven dogs underwent selective lung ventilation and thoracoscopic partial pericardectomy. Surgery sites in both groups were bandaged and each dog received a single postoperative dose of morphine (0.2 mg/kg, intramuscularly [i.m.]). Postoperative pain was evaluated using a standard pain score table at 1, 5, 9, 17, 29, and 53 hours after surgery. Dogs receiving a pain score of six or greater received an additional dose of morphine. At each observation point, blood samples were taken to measure blood glucose and plasma cortisol concentrations. Pain scores, blood glucose, and plasma cortisol concentrations were compared between the two groups using two-way ANOVA. RESULTS: Blood glucose concentrations, plasma cortisol concentrations, and pain scores were significantly different between the two groups, with the thoracotomy dogs having higher values at 1, 5, and 9 hours postoperatively. Three of the open thoracotomy dogs required additional analgesia after the initial dose of morphine. In addition, two dogs that underwent open thoracotomy were lame in the left forelimb and two others developed dehiscence of their wounds. CONCLUSIONS AND CLINICAL RELEVANCE: Thoracoscopic partial pericardectomy has several advantages over open partial pericardectomy including decreased postoperative pain, fewer wound complications, and more rapid return to function. 相似文献
97.
OBJECTIVE: To examine the effect of darglitazone, a compound of the thiazolidinedione class, on glucose clearance and lipid metabolism in obese cats. ANIMALS: 18 obese and 4 lean adult neutered female cats. PROCEDURE: IV glucose tolerance tests with measurements of glucose, insulin, and nonesterified fatty acid (NEFA) concentrations were performed before and 42 days after daily administration of darglitazone (9 obese cats) or placebo (9 obese and 4 lean cats). Additionally, cholesterol, triglyceride, leptin, and glycosylated hemoglobin concentrations were measured. RESULTS: Darglitazone-treated cats had significantly lower cholesterol, triglyceride, and leptin concentrations, compared with placebo-treated obese cats. A significant decrease in the area under the curve for NEFAs, glucose, and insulin during an i.v. glucose tolerance test was seen in darglitazone-treated cats. The drug was well tolerated. CONCLUSION AND CLINICAL RELEVANCE: The response of obese cats to darglitazone was similar to the response to thiazolidinediones in obese humans and rodents Darglitazone was effective in improving insulin sensitivity and glucose and lipid metabolism in obese cats. 相似文献
98.
99.
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
100.