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Reproductive traits of heifers and primiparous cows from a long-term selection project were analyzed to determine correlated response to single-trait selection for milk yield. Data were from 1056 daughters (765 selection, 291 control) of 37 bulls (17 selection, 20 control). Traits in heifers were ages at first observed estrus and at first breeding, services to conception, interval from first service to conception, and length of first gestation. Traits in primiparous cows were ages at first calving and at first breeding, after calving; services to conception; length of second gestation; and intervals from calving to first observed estrus, to first breeding, and to conception, from first service to conception, and from first to second calving. Analyses for services to conception in heifers and primiparous cows were categorical using models containing genetic group and generation. Analyses of other traits were by linear mixed models using fixed effects of genetic group, generation within group, and year-season of birth. Sires were assumed random and nested within genetic group. The mean square for sires within group was used to test for group differences. No significant differences were found between genetic groups in traits measured in heifers; however, the interval from first service to conception approached significance (control superior). In primiparous cows, differences between genetic groups were significant for the intervals of calving to first breeding and calving to conception and for length of second gestation (control superior). For other traits, reproductive performance of the control was better but not significantly different from that of the selected group. Reproductive performance should be monitored during selection for high milk yield.

Growth and body measurements from a long-term selection project were analyzed to determine correlated responses to single-trait selection for milk yield. Data were from 1056 daughters (765 selection, 291 control) of 37 bulls (17 selection, 20 control) of 37 bulls (17 selection, 20 control) and included BW and measures of heart girth, chest depth, wither height, and length from withers to pins and from withers to hooks taken at 6 mo, 15 mo, first calving, end of first lactation, and maturity. Other data were birth weight, change in measurements and weights from first calving to end of first lactation, monthly rate of gain from 1 to 13 mo of age, and age reaching breeding weight (250 kg). Principal component scores were calculated from standardized measurements at each age. The first three principal components has meaning (size, length vs. girth, and height vs. girth). All analyses used linear mixed models with fixed effects of genetic group, generation within group, year-season of birth or calving, parity of dam, and birth status (multiple or single birth). Sires were assumed to be random and nested within genetic group. Mean squares for sires was used to test for group differences. Generation did not differ in any analysis and was removed from all models. Selection cows were heavier, larger in some measurements, and had greater overall size at 6 mo of age. Selection cows had greater monthly rate of gain and attained breeding weight at an earlier age. Genetic groups did not differ for any other measurement or weight. Control cows gained more weight and increased more in some measurements between first calving and end of first lactation. Selection for milk yield did not result in an undesirable correlated response in an growth or body measurement.

In 1967, the Jersey herd at the Dairy Experiment Station, Lewisburg, TN was divided into two groups on the basis of ancestry, type, and breeding value for milk as part of a project to determine effects of single trait selection for high milk yield on yield and correlated traits. Control group was mated randomly to 20 unproven young sires selected randomly from those available from breeding studs in 1967. Selection group was mated to sires selected solely on the basis of their high transmitting ability for milk. Selection sires were selected at intervals and used for 4 yr. By the end of the project (1984), lactation information was available on 672 daughters (520 selection and 152 control) of 37 bulls (17 selection and 20 control). Differences in breeding values for milk, fat, and fat test as calculated from the PTA reported in the July 1989 USDA genetic evaluations and differences in first lactation mature equivalent production of milk, fat, fat test, and 4% FCM were examined. Linear mixed models were used for all analyses and contained the fixed effects group, generation within group, and year. Sires were random, nested within group, and used to test for group differences. Groups differed for all traits. Selection was superior to control in breeding value for milk and fat (828 and 31 kg) and for production of milk, fat, and 4% FCM (1066, 42, and 1061 kg). Control was superior to selection in breeding value and production fat test (.15 and .12%). Group differences existed within generation class for all yield traits but not for fat percentage. Realized response closely matched or exceeded expected response as estimated from pedigree information.

Low temperature methods of producing thin coatings of cadmium selenide on a steel substrate are described. These coatings are suitable for solar to electrical energy conversion and have been used in a photoelectrochemical cell employing a cadmium selenide-stabilizing redox couple, which converts sunlight to electricity at a 1% power conversion efficiency without deterioration of the CdSe photoanode. Possible improvements in the coating quality and cell design are considered, and the eventual attainment of a 4% conversion efficiency is considered feasible.

Incidence of clinical mastitis in 1278 lactations of 390 Jersey cows was studied for effects of lactation number, quarter of udder, month of calving, sire, and milk yield. Results for quarter did not conflict with the usual finding that incidence is higher in rear quarters. A mastitis index based on stage of lactation at which infection occurred had less variation, greater variation among sires, and a continuous distribution, in contrast to the traits porportion infected and number of cases. Mastitis increased with advancing lactation number subsequent to second lactations. Fall calvers may have less mastitis since they would be dry or in late lactation during summer. Incidence of mastitis increased at a decreasing rate as total milk yield in the lactation affected increased.

Thirty milking Jersey cows were in each of two 12-wk continuous feeding trials to compare a) corn silage with 19% crude protein concentrate, b) alternate feedings of corn silage and wheat silage with 19% concentrate, and c) alternate feedings of corn silage and alfalfa silage with 15% concentrate. Digestibility of corn silage, wheat silage, and corn silage fed alternately with either wheat or alfalfa silages was measured with bred heifers. Wheat silage was harvested in the boot stage, alfalfa silage in the bud to early bloom stage, and corn silage in the dent stage. Daily intake of forage dry matter and production of fat corrected milk were higher on the corn-alfalfa ration than on the corn-wheat ration. Intake and production were intermediate on corn silage fed alone and not different from those on corn silage fed in alternate feedings with either alfalfa or wheat. Apparent digestibilities of dry matter and acid detergent fiber were higher for corn silage than for wheat silage; however, digestibilities of dry matter, crude protein, and fiber of the corn-wheat and corn-alfalfa rations were not different from those of corn silage fed alone.

Thirty-two lactating cows were in each of two feeding trials to compare: 1) formic acid treated corn silage, 2) untreated corn silage, 3) formic acid treated wheat silage, and 4) untreated wheat silage. Formic acid (82%) was added at the silo at .5% of the green forage weight. In the milk production trials, dry matter intake, actual milk, fat-corrected milk, and body weight gain were higher for corn silage than for wheat silage, but there were no significant responses in milk production to the formic acid treatments. Treatment of corn and wheat silages with formic acid resulted in higher pH and residual sugar content but less production of lactic acid, acetic acid, and ammonia. Digestibility of silages was determined with 48 bred heifers. Dry matter intakes and digestibility coefficients for dry matter, crude protein, and acid detergent fiber were greater for corn silage than for wheat silage and for formic acid treated than for untreated silages.

Daughters of bulls selected for PD milk (selection line) were compared to random bred controls at the University of Tennessee-USDA Dairy Experiment Station. Jersey classification data were divided: 1) 166 selection and 82 control cows scored under the categorical system (1971 to 1979); and 2) 152 selection and 45 control cows scored under Uniform Functional Type Traits Appraisal (1980 to 1984). Least squares analysis compared first parity scores, adjusted for age and stage of lactation, of selection line cows with those of controls. Type scores from both data sets were dependent variables in a mixed model including effects of date classified, line, and sire within line. Linear scores of selection line cows were higher for dairy character (82.4 vs. 76.1) and final score (76.9 vs. 73.6). Dairy character scores (86.2 vs. 84.7) were higher for selection line cows in the categorical subset. Line means for other nonlinearly scored traits were not different. For linear data, dairy character rating explained much of the variation in final score. Other important traits in this regard include front teat placement, fore udder, foot angle, and suspensory ligament. These results reflect emphasis placed on priority traits by the American Jersey Cattle Club.

A study involving 357 Jersey cows at the Dairy Experiment Station was conducted to determine the effects of post-partum intrauterine treatment of two formulations on several reproductive parameters. In phase I, animals were treated with a bolus containing an antibiotic, smooth muscle stimulant, and estrogen. Phase II animals were treated with two uterine boluses containing nitrofurazone and urea. Alternate cows were treated and untreated cows served as controls. Neither treatment resulted in any significant (P > 0.05) improvement over control animals in any of the reproductive efficiency parameters measured.

A novel method of interface temperature detection is described in which the junction of the crystal and melt acts as the hot limb of a thermocouple. Theoretical analysis shows that although the method at present cannot measure absolute temperature, measurements of medium frequency (approximately 0.2 Hz) temperature variations can be very sensitive. This technique was applied during the growth of InSb, and temperature variations similar to those found by other workers using thermocouples in convectively unstable melts were detected.

Johnstone (prevarietal release) and Kenhy, new varieties of tall fescue ( Festuca arundinacea Schreb ), were compared with Boone orchardgrass ( Dactylis glomerata ) in 2 yr. Cultivars were maintained in a vegetative stage by removal of excess growth. Johnstone seed and the resulting cultivar were 6.7% infected with endophyte fungus ( Acremonium coenophialum ). Forage from each cultivar was chopped daily and fed individually to five lactating Jersey cows for 12 wk in 1983 and to eight cows for 9 wk in 1984. Cows were fed 6.8 and 4.5kg daily of a 16% crude protein concentrate in 1983 and in 1984, respectively. No evidence of fescue toxicosis was observed in 1983, but a trend toward depressed prolactin occurred in 1984 for Johnstone tall fescue. Daily dry matter intake, intake as percent body weight, and daily milk production were significantly higher on orchardgrass than on tall fescues. Intake as percent body weight, daily milk, milk protein, and fat-corrected milk were significantly higher on Johnstone than on Kenhy tall fescue. Although the experimental design did not allow direct comparison, performance appeared to be as good on Johnstone fescue as on orchardgrass. The inferior animal performance on fescue compared with orchardgrass seems to be due entirely to Kenhy.

Gross feed efficiency (milk energy output divided by energy consumed) was measured in 232 Jersey cows resulting from direct selection for milk yield and a control line of 121 daughters of 20 Jersey bulls taken randomly from commercial artificial insemination sampling programs in 1967. Data were collected between 1971 and 1982 from primiparous cows in middle to late lactation in 21 feeding trials of 28 d. Cows were fed hay and silage ad libitum plus grain according to production at the rate of 1 kg grain/3 kg milk. Models for least squares analyses included trial, line, days in milk, and either body weight change (model 1) or energy balance (model 2), estimated as the difference between energy requirements and actual energy intake. Body weight change was an insignificant source of variation, and gross feed efficiency did not differ between genetic lines using model 1. Significant line differences in gross efficiency were obtained after adjusting for energy balance; however, problems of multicollinearity invalidates meaningful inference. Results indicate genetic lines of Jerseys did not differ in gross feed efficiency when fed according to yield and suggest selection has not affected efficiency of direct conversion of nutrients into milk.

Forty-eight lactating Jersey cows were used in each of 2 yr to evaluate three forage systems: corn silage and alfalfa hay fed in dry lot; corn silage and approximately 5h of pasture daily; and green chop, alfalfa hay, and 5h of pasture daily. Two rates of concentrate feeding were used. One-half of the cows on each forage system were fed concentrates at 1kg of concentrate to 3kg of 4% fat-corrected milk, and the other one-half were fed concentrates at 1:6. Daily milk and 4% fat-corrected milk production were higher on the two pasture systems than on corn silage and alfalfa hay fed in dry lot. Body weight gains were higher for cows on forage-dry lot system than on pasture systems. Differences in milk production between pasture systems were not significant. Neither differences in production due to rates of concentrate feeding nor interactions of forage system×rate of concentrate feeding were significant.

Lactating Jersey cows were used in two trials to evaluate alfalfa-orchardgrass hay baled and stored by the following methods: 1) conventional rectangular bales; 2) large round bales, stored inside; and 3) large round bales, stored outside. Half the round bales stored outside in trial 1 were stored on automobile tires and the other half were stored on the gound. In trial 2, half of the bales stored outside were partially covered with plastic caps and the other half were exposed to the weather. Covariance adjusted milk production was significantly higher for inside over outside storage in trial 1 and for conventional over round bales and covered over exposed in trial 2. In trial 1, utilization by cows as a percent of dry matter baled was 92.9, 74.0, and 66.6% for round bales stored inside, stored outside on tires, and stored outside on the ground. Percents were 86.8, 88.8, and 65.0% for round bales stored inside, stored outside covered, and stored outside exposed in trial 2. Storing round bales on automobile tires effectively reduced bottom spoilage. Covers of polyethylene film reduced weather deterioration and feeding waste of covered bales to amount of bales stored inside.

Data were collected in a 3-yr experiment to compare the intake, milk production, and return above feed cost of cows fed soybean-grain sorghum silage with those of cows fed corn silage. In the last yr, soybean-grain sorghum was harvested at the flower stage of the soybean plants. In the 2nd and 3rd yr, soybean-grain sorghum was harvested at both the flower and early bean stages. In all 3 yr corn silage was harvested in the dent stage of maturity. Ten cows in early lactation were on each treatment in each of the 3 yr (80 cows) to evaluate the silages. Cows fed corn silage consumed 10, 12, and 20% more dry matter and produced 1.8, 1.9, and .8kg more fat-corrected milk daily than those fed flower stage soybean-grain sorghum for yr 1 to 3. Cows fed corn silage consumed 3 and 14% more dry matter and produced 1.8 and 2.0kg more fat-corrected milk than cows fed the early stage bean. Corn cost more per hectare than soybean-grain sorghum to grow each year, but the cost per unit silage produced was less. Higher daily milk production coupled with lower silage cost resulted in consistently greater return above feed cost for corn silage.

Forty-eight lactating Jersey cows were used in a 2-year study to evaluate three forage systems: (A) Corn silage and alfalfa hay; (B) corn silage, green chop, and alfalfa hay; and (C) pasture, green chop, and alfalfa hay. Half of the cows on each forage system were fed concentrates individually with the remaining cows fed the same total amount of concentrates as a group. Rate of feeding was 1 kg concentrates for each 4.5 kg of 4% fat-correct milk, (FCM). Treatments were compared continuously for 17 and 12 weeks, respectively, in 1968 and 1969. Twenty cows were used in a preliminary study in 1967 to compare group and individual feeding of concentrates. Daily milk and FCM production were lower on forage system A than forage system B, which in turn was lower than system C. Body weight gain was higher on forage systems A and B than on forage system C. There were no significant forage-grain system interactions in these trials. In the preliminary trial, cows fed grain individually produced less FCM than their mates fed the same amount of grain as a group. However, the method of grain feeding did not significantly affect FCM production in the two-year study.

Chopped alfalfa-orchardgrass forage was further lacterated to an almost pulpy consistency and compared with the same forage chopped by a conventional forage chopper. Experimental silages were stored in 3.05- by 12.19-m concrete stave tower silos. Lacerated silage had a lower ammoniacal nitrogen, butyric acid, and propionic acid content, and a higher per cent lactic acid in the top 20% of the silage than the chopped silage. There were no chemical differences in the bottom 80% of the silage, indicating that pressure within the lower part of the chopped silage mass probably acomplished an effect similar to the laceration process. There was no significant difference in the feeding value of the two silages.

Lactation records of 228 first lactation Jerseys were utilized to assess the importance of sire×ration interactions. Daughters of 13 sires were divided randomly into two groups at calving and assigned to either an all forage ration or a forage plus grain ration. Data were analyzed by least squares methods with year-seasons, sires, rations, and sire×rations interactions included in the model. Ration differences were large and indicative of the stress of the all forage ration. The all forage group produced 83% as much milk, consumed 9.6% more forage but only 58% as much estimated net energy, and was more efficient than the forage plus grain group. The sire×ration interaction approached significance for milk and fat-corrected milk production (.l0>P>.05) but contributed less than 4% of the total variation. The sire×ration interaction was significant for total estimated net energy consumed and gross efficiency. This interaction may be because the amount of grain fed in the forage plus grain group was controlled by production.

Summary Corn, and one or more varieties of sorghum, were grown for silage in alternate strips in the same field in three tests. The yield of corn was considerably less than any variety of sorghum each year, especially during the dry summer of 1954. One double-reversal and two Latin-square design feeding trials were conducted with from 22 to 27 cows in each test, to compare silage from these crops. Cows produced more milk, consumed more silage, and gained more weight each year on the corn silage than on any variety of sorghum. These differences were highly significant (P

Each of two feeding trials used 32 first and second lactation Jersey cows to evaluate four methods of protein supplementation of corn silage: A) 20% crude protein grain mixture, B) 1.36 kg of soybean meal replaced an equal amount of grain mixture, C) 2.27 kg of alfalfa-orchardgrass hay daily and 16% crude protein grain mixture, and D) 2.72 kg of soybean meal mixed with the silage daily. Concentrates were fed at 1 to 4 kg fat-corrected milk for treatments A, B, and C. All cows received 1.18 kg of 16% crude protein concentrate mixture daily in the milking parlor. Protein contents, as percents of dry matter intake, for respective treatments were 12.9, 15.0, 12.7, and 17.2. Treatments did not differ significantly for milk production, fat-corrected milk, and change of body weight; however, percents milk fat for 1.36 and 2.72 kg soybean meal were higher. In trial 2, protein insolubility of ration components was determined by four extracting methods: A) autoclaved rumen fluid, B) sodium chloride solution, C) Burroughs’ solution, and D) boiling water. Insoluble protein intake determined by autoclaved rumen fluid and hot water methods accounted for more of the variance of milk and fat-corrected milk production than total protein intake.