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1.
A comparison was made between the genes in 29 new selections of wild emmer wheat resistant to yellow rust over wide geographic areas and the previously extensively studied selectionTriticum dicoccoides G-25. In 23 selections the resistance may be conferred by 1 dominant gene; these include 11 selections in which the gene is different from the dominant gene in sel. G-25 and two others in which the genes were closely linked or allelic to the gene in G-25, differing from sel. G-25 by race-specificity. Two dominant genes different from the gene in sel. G-25, seem to be present in one selection. In five selections the resistance may be conferred by one or two recessive genes, including three instances in which the recessive gene was associated with a dominat gene. Our findings show that at least 19 out of the 29 selections studied possess genes which are different from the gene inT. dicoccoides sel. G-25.Samenvatting In dit onderzoek werden 29 nieuwe resistente wilde-emmer selecties (Triticum dicoccoides) gekruist met de reeds uitvoerig bestudeerde resistente selectie G-25, om na te gaan of de resistentie van de nieuwe selecties wordt veroorzaakt door genen op dezelfde locus als het dominante gen in sel. G-25 of dat er andere loci bij zijn betrokken. De ouders, de F1-en F2-populaties van een bepaalade selectie werden in het kiemplantstadium getoetst met één Israëlisch gele-roest isolaat van fysio 2E0 of van fysio 2E18. In de uitsplitsende F2-populaties werden de niet-sporulerende planten als resistent beschouwd en de sporulerende als vatbaar.In de F2-populaties van 12 herkomsten werden geen vatbare planten gevonden, hetgeen er op duidt dat de resistentie wordt veroorzaakt door een gen op dezelfde locus als het gen in G-25 of door een gen dat neuw gekoppeld is aan het gen in G-25. Voor twee van deze herkomsten kan op basis van een fysio-specifieke interactie worden vastgesteld dat de resistentie berust op allelen die verschillen van het allel in sel. G-25. In 11 herkomsten werd een uitsplitsing voor twee dominante gene gevonden (RS=151), waarbij het tweede dominante gen uit de getoetste nieuwe selectie afkomstig is. De aanwezigheid van twee dominante genen verschillend van het gen in sel. G-25 werd gevonden in één herkomst (631). In de overige vijf selecties bleek de resistentie te worden veroorzaakt door één of twee recessieve genen waarnaast in drie gevallen ook nog een dominant gen werd gevonden.De resultaten tonen aan dat tenminste 19 van de 29 bestudeerde selecties resistentiegenen bezitten die verschillen van het gen inT. dicoccoides sel. G-25. Slechts in twee van deze selecties kan het gen allel zijn met het gen in sel. G-25.  相似文献   
2.
The effects of corn replacement by cassava dreg in diets of crossbred goat kids were evaluated. We tested the impacts of 0, 33, 66 and 100% replacement on intake, digestibility, feeding behaviour, performance and carcass characteristics. Thirty-six goat kids, aged between 4 and 5 months and with initial body weights of 17.61 ± 1.98 kg, were used in a completely randomised design. Analysis of regression revealed a negative linear effect on neutral detergent fibre (NDF) intake and a positive linear effect on non-fibrous carbohydrates (NFC) and hydrocyanic acids (HCN) intake. Cassava dreg use had a positive linear effect on organic matter digestibility and non-fibrous carbohydrates. Based on our results, cassava dreg use did not negatively impact animal performance, feeding behaviour and carcass characteristics, suggesting that it may replace corn up to 100% in the diets of confined goat kids.  相似文献   
3.
In this study, we evaluated the effects of including cassava wastewater in the diet on the feeding behavior of feedlot lambs in 35 male uncastrated Santa Inês × Dorper crossbred lambs at an approximate age of 3 months, with an average live weight of 20.0?±?3.4 kg. Diets were formulated with hay of cassava shoots (roughage) and a concentrate based on corn and soybean, with a roughage:concentrate ratio of 50:50, plus inclusion of cassava wastewater at the levels of 0, 12, 24, 36, or 48 g/kg of the total diet. Feeding behavior was evaluated between the 46th and 52nd days of the experiment. Increasing cassava wastewater levels in the diet reduced (P?<?0.05) the intakes (kg/day) of dry matter and neutral detergent fiber as well as the efficiency of rumination (g/cud and g/h) of dry matter and neutral detergent fiber. The other behavioral parameters were not affected by wastewater inclusion in the diet. Therefore, the inclusion of up to 48 g/kg of cassava wastewater on fresh matter of diets is not recommended for feedlot lambs.  相似文献   
4.
This study compared the productive and nutritional parameters of milk from crossbred lactating cows managed on Panicum maximum Jacq. cv. Tanzania and with a diet supplemented with different pressed oilseed cakes. The supplements used were as follows: peanut cake, sunflower cake and palm kernel cake for replacement of soybean meal. Sixteen cows with an average weight of 544 ± 57 kg and producing 8 ± 1.4 L of milk per day were used in this study. The animals were randomly assigned to the treatments according to a Latin square design repeated over time, with four treatments, 16 animals and four experimental periods. Supplementation of the diet with peanut cake, sunflower cake and palm kernel cake compared with soybean meal in the diet of cows did not affect the average daily production or composition of the milk. The palm kernel cake promoted an increase in lauric fatty acids (C12:0) and palmitoleic acids (C16:1) (5.02 and 1.65%, respectively) compared with peanut cake and sunflower cake (4.13 and 4.01%, respectively). The levels of oleic fatty acids (C18:1) were higher for the sunflower cake and palm kernel cake supplements (26.01 and 25.01%, respectively) compared with peanut cake (23.11%). The replacement of soybean meal with sunflower cake and palm kernel cake improved the nutritional quality of the milk, with lower concentrations of saturated fatty acids and higher concentrations of unsaturated fatty acids, without compromising the production or nutritional composition of the milk. © 2015 Japanese Society of Animal Science  相似文献   
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Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for...  相似文献   
7.
In this study, films of chitosan and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (6CN), a 2-aminothiophene derivative with great pharmacological potential, were prepared as a system for a topical formulation. 6CN-chitosan films were characterized by physicochemical analyses, such as Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Additionally, the antifungal potential of the films was evaluated in vitro against three species of Candida (C. albicans, C. tropicalis, and C. parapsilosis). The results of the FTIR and thermal analysis showed the incorporation of 6CN in the polymer matrix. In the diffractogram, the 6CN-chitosan films exhibited diffraction halos that were characteristic of amorphous structures, while the micrographs showed that 6CN particles were dispersed in the chitosan matrix, exhibiting pores and cracks on the film surface. In addition, the results of antifungal investigation demonstrated that 6CN-chitosan films were effective against Candida species showing potential for application as a new antifungal drug.  相似文献   
8.
Objective To characterize responses to different doses of propofol in horses pre‐medicated with xylazine. Animals Six adult horses (five females and one male). Methods Each horse was anaesthetized four times with either ketamine or propofol in random order at 1‐week intervals. Horses were pre‐medicated with xylazine (1.1 mg kg?1 IV over a minute), and 5 minutes later anaesthesia was induced with either ketamine (2.2 mg kg?1 IV) or propofol (1, 2 and 4 mg kg?1 IV; low, medium and high doses, respectively). Data were collected continuously (electrocardiogram) or after xylazine administration and at 5, 10 and 15 minutes after anaesthetic induction (arterial pressure, respiratory rate, pH, PaO2, PaCO2 and O2 saturation). Anaesthetic induction and recovery were qualitatively and quantitatively assessed. Results Differences in the quality of anaesthesia were observed; the low dose of propofol resulted in a poorer anaesthetic induction that was insufficient to allow intubation, whereas the high dose produced an excellent quality of induction, free of excitement. Recorded anaesthesia times were similar between propofol at 2 mg kg?1 and ketamine with prolonged and shorter recovery times after the high and low dose of propofol, respectively (p < 0.05; ketamine, 38 ± 7 minutes; propofol 1 mg kg?1, 29 ± 4 minutes; propofol 2 mg kg?1, 37 ± 5 minutes; propofol 4 mg kg?1, 50 ± 7 minutes). Times to regain sternal and standing position were longest with the highest dose of propofol (32 ± 5 and 39 ± 7 minutes, respectively). Both ketamine and propofol reversed bradycardia, sinoatrial, and atrioventricular blocks produced by xylazine. There were no significant alterations in blood pressure but respiratory rate, and PaO2 and O2 saturation were significantly decreased in all groups (p < 0.05). Conclusion The anaesthetic quality produced by the three propofol doses varied; the most desirable effects, which were comparable to those of ketamine, were produced by 2 mg kg?1 propofol.  相似文献   
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A tsetse and bovine trypanosomosis survey was conducted during 1998 and 1999 in the Matutuine District of Maputo Province (Mozambique). A total of 59 Glossina brevipalpis and 17 Glossina austeni were captured throughout the district. Survey results suggest that Glossina brevipalpis is mainly concentrated in dense vegetation along the Maputo River and in the wetlands east of the river. G. austeni, on the other hand, was captured mainly in dense thickets in drier areas. Both tsetse species are suspected to be vectors of bovine trypanosomosis. Bovine trypanosomosis (75,5% Trypanosoma congolense) was diagnosed in 53 animals (13,9%) from seven sampling sites distributed throughout the district. The prevalence of cattle with anti-trypanosomal antibodies was high (29,9%).The incidence of trypanosomal infections in sentinel cattle was also high. The widespread distribution of bovine trypanosomosis and the high prevalence of infection are likely to have a significant impact on cattle production and, hence, the cattle restocking exercise in the district.  相似文献   
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