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Age-season adjusted records from five breeds of dairy goats on Dairy Herd Improvement test from 1965 to 1976 were used to estimate components of variance for milk yield, fat yield, and fat percentage. The data were 6,452 Alpine, 1,730 LaMancha, 6,897 Nubian, 2,759 Saanen, and 4,007 Toggenberg lactation records. Components of variance were estimated by Henderson's Method 1 with a four-way model that included random effects of herd, year-season, sire, and doe. Herd effects accounted for 22 to 31% of the total variation in milk and fat yields and 15 to 25% of the variation in fat percentage. These effects were large enough to indicate that they must be considered in genetic evaluations of milk and fat production. Sire components of variance were 8 to 10% of the total variation in milk yield, fat yield, and fat percentage. Does accounted for 16 to 25% of total variation in milk yield, fat yield, and fat percentage. Repeatabilities of milk yield, fat yield, and fat percentage varied from .39 to .55 whereas heritabilities also within herd-year-season ranged from .48 to .62. Heritabilities larger than repeatabilities indicate that confounding may have inflated sire effects. Phenotypic and genetic correlations between milk and fat yields averaged .94 and .86. Milk yield and fat percentage were correlated negatively both phenotypically and genetically, whereas genetic correlations between fat yield and fat percentage averaged. 18.

Only part of the active ingredient used in agrochemical applications in orchards is retained on the trees. The product that is not retained is lost as sedimentation in the soil and as drift, the latter being a major source of environmental pollution. Unfavorable atmospheric conditions affect the uniformity of distribution and increase product loss. This can be mitigated by the utilization of larger drops. The objective of the present work was to evaluate the effect of service pressure on distribution in the trees and product loss by using a conventional hydro pneumatic sprayer. A fluorescent tracer was applied on fruit trees by an airblast sprayer, with two treatments: high pressure (1800 kPa) and low pressure (500 kPa). Samples were collected from the trees, in columns and from the soil. The results indicated that there were no differences between the two treatments in the total quantity of deposits recovered from leaves. There was one third less drift with the low-pressure than with the high-pressure treatment, whereas deposits on the soil were similar with the two treatments, with the low-pressure treatment presenting a higher concentration of deposits in the proximity of the treated row. In conclusion, the use of sprayer systems that operate with low pressure is a valid alternative to reduce environmental pollution because it tends to loss to the area where the treatment is being applied, without affecting deposits on the trees.

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