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11.
1962—1963年在四川省泸县地区进行油茶炭疽病的防治試驗。結果表明:采用营林措施(修除树上病部)和化学保护(噴射1∶1∶150波尔多液)的综合防治方法,病株防治效果可达89.77%,防止果病率达70.02%。严重病区,可在冬(12月)、春(2月)修除病部各一次(或可集中在2月进行),发病期間(4—8月)噴射波尔多液8—10次(条件不許可山区,也至少5次)。噴药宜連續性。上述措施,应进行2—3年。 相似文献
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The effects of sufficient milk intake as well as of 32 hours of fasting after birth, administration of actinomycin D (intraperitoneal application of 1 mg/kg five weight), and fasting in combination with actinomycin D on the development of body and liver weights, crude protein levels in homogenate and supernatant of liver, kidneys, and M. semitendinosus as well as on the activities of certain tissue enzymes were analysed with four groups of piglets (n = 4). Fasting, administration of actinomycin, and fasting in combination with actinomycin D resulted in rapid reduction in body and liver weights, while the crude protein levels in those tissues were not affected with significance. GOT and fructose-1,6-diphosphatase activities in supernatant from liver tended to decline under fasting conditions. The ATPase activity in the homogenate of the above tissues did not change in response to differentiated treatment. 相似文献
14.
4 digestibility trials (4 male sheep per group) and 2 growth trials were carried out with 24 (V 1) and 32 (V 2) fattening lambs to investigate the effect of abundant oral Fe doses on the digestibility of crude nutrients in a ration of barley + dried green feed and on the results of fattening and carcass yields. Fe supplementation (less than 1400 mg per sheep/day) did not significantly change the digestibility coefficients of crude nutrients. Increasing Fe levels in the concentrates decreased the rates of liveweight increase and food consumption in both growth trials. Well-established statistical evidence was provided for the decline in absolute carcass yields resulting from the lower weight of the lambs at the end of the fattening period after Fe supplementation. 相似文献
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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
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Evaluation of sampling methods and assessment of the sample size to estimate the weed seedbank in soil, taking into account spatial variability 总被引:1,自引:0,他引:1
As field sampling is time consuming, it is necessary to develop efficient sampling techniques to obtain accurate estimates of the weed seedbank in soil. The relative efficiency between sampling schemes depends on the spatial variability in weed seed density across agricultural fields. Spatial variability of the weed seed density was characterized by theoretical correlograms. A systematic sampling (square grill) scheme was considered and it was found that, taking into account spatial variability, this sampling scheme was more efficient than simple random sampling. As a result, the sample size can be reduced in comparison with that given in previous studies, where spatial correlation was ignored. The reduction depends on the correlation structure defined as a function of the ratio, τ, between the nugget effect and the sill of the variogram. The maximum reduction of the sample size, without loss of either precision or confidence level corresponds to the case where there is no nugget effect, τ = 0. The opposite extreme case, where the reduction is nil, corresponds to the case of a pure nugget effect τ = 1. The abaci based on given expressions are provided to determine the sample size in species whose spatial pattern can be fitted either to a Poisson or to a negative binomial distribution. 相似文献
19.
Azarpajouh S. Marchewka J. Segura Correa J. C. Calderón Díaz J. A. 《Tropical animal health and production》2018,50(6):1343-1348
Tropical Animal Health and Production - The objective of this study was to compare hoof anatomy, hoof growth pattern, and hoof weight-bearing surface of six different Iranian sheep breeds to... 相似文献
20.
C. Ruíz-Guevara F. De León-González R. Soriano-Robles A. L. Pérez-Carrera L. A. García-Hernández 《Tropical animal health and production》2018,50(3):469-476
The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15–22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region. 相似文献