Biomedical subjects

J G Linn

Publications and source records attributed to J G Linn.

At least 37 records · Page 2Linked to original sources

PubMed1991

Forage quality analyses and interpretation.

The minimum analyses needed to determine the quality or nutritive composition of forages are DM, CP, ADF, NDF, Ca, and P. The accuracy of these and other analyses are affected by the sampling and analysis methods. Improper sampling is probably one of the largest but most overlooked sources of variation in analysis. Analysis methods must be both accurate and precise. New techniques like NIRS can be just as accurate and have better precision than conventional chemistry methods if correctly calibrated. Finally, understanding variations associated with the analysis and discerning sources of the variation as to errors in analysis, sampling, or natural variation caused by environmental growing conditions, plant species, or harvest practices is the biggest challenge for nutritionists. Forages cannot be fully and efficiently utilized in the diets of dairy cattle until their composition is accurately determined and interpreted for animal performance.

Animal Feed↗

PubMed1991

Social density, stressors, and depression: gender differences among the black elderly.

This research examined gender differences with regard to the effects of social density and stressors upon depressive symptomatology among 600 Black elderly community residents (aged 55-85 years) of Nashville, Tennessee. The sample had more females than males and fewer married individuals. Approximately half of the males and females lived alone. Regression analyses show that poor ego and chronic medical problems were the common predictors of depression among both the males and females. Gender differences were found with regard to life events in that females tended to become more depressed as the number of events increased and as level of contact with relatives and friends decreased. Further, females with lower levels of social attachment, guidance, and reliability were more depressed. None of these social support dimensions related to depression among the males. These relationships tended to be stronger for those living alone than for those living with others.

Black or African American↗

PubMed1991

Effects of dietary protein-energy interrelationships on Holstein steer performance and ruminal bacterial fermentation in continuous culture.

In vivo and in vitro 3 x 2 factorial experiments were conducted concurrently to evaluate the incorporation of 0, 15, or 30% sugar beet pulp (SBP) as an energy source in diets fed to growing Holstein steers with either soybean meal (SBM) or alcohol-treated, defatted soybean flakes (ATSBF) as primary supplemental protein sources. Three groups of 42 Holstein steers each were fed six different diets from 54 kg initial BW to 320 kg in three experimental periods. There were no overall SBP level x protein source interactions (P greater than .05). Beet pulp level tended to decrease ADG (linear, P = .05) and increase feed/gain (linear, P less than .05) and DMI (quadratic, P less than .05). Each grower diet was used in a substrate for ruminal microbial metabolism in six dual-flow, continuous-culture fermenters. Organic matter and carbohydrate digestion were similar (P greater than .05) among diets. Increasing dietary levels of SBP caused a concomitant increase (P less than .05) in acetate and decrease (P less than .05) in butyrate and isobutyrate concentrations. Beet pulp level x protein source interactions (P less than .05) were observed for CP degradation, ammonia and nonammonia N, and dietary N flow. Crude protein degradation was higher (P less than .05) for the 0% SBP with SBM diet (81.3%) than for the 30% SBP with ATSBF diet (64.4%). Efficiency of bacterial synthesis was similar (P greater than .05) among diets. Results indicated that SBP is an effective dietary energy source for high-energy grower diets at 15 or 30% of the DM but may cause a decrease in some performance traits. There were no nutritional benefits of using ATSBF vs SBM as the supplemental N source.

Animal Feed↗

PubMed1991

Influence of forage type, ratio of forage to concentrate, and methionine hydroxy analog on performance of dairy cows.

In a 2-yr study, 44 primiparous and 77 multiparous cows were assigned to one of 12 dietary treatments (2 X 3 X 2 factorial). Treatments were two forages (alfalfa or smooth bromegrass), three percentages of grain (40, 50 or 60% of diet DM), and two percentages of methionine hydroxy analog (0 or .15% of diet DM). Feeds were offered as total mixed diets. Data collection began 4 d postpartum and continued through 116 d postpartum. Dry matter intake was not affected by percentage of concentrate or forage source even though NDF of the diets ranged from 25.6 to 48.8% and ADF ranged from 15.7 to 36.8%. Cows fed bromegrass hay produced 1.5 kg/d more FCM and 1.2 kg/d more SCM than those fed alfalfa hay. Concentrate percentage in the diet increased milk yield (28.9, 30.4 and 31.3 kg/d at 40, 50 and 60%, respectively). Methionine hydroxy analog increased milk fat percentage and yield for cows fed diets of 50 and 60% concentrate with alfalfa hay but not for those fed diets of 50 and 60% concentrate with bromegrass hay. Effect of methionine hydroxy analog was not significant for milk fat or yield when diets of 40% concentrate were fed.

Age Factors↗

PubMed1990

An evaluation of a therapeutic health program for the black elderly.

This paper evaluates the effectiveness of a therapeutic health program which was offered in 1988 to the black elderly living in subsidized high-rise apartments in Nashville. The pre-program data (of 1987) indicated distinct differences in that the elderly living in the high-rises had significantly more medical problems, higher levels of depression, and smaller social support networks than those living in their own single dwelling homes. The therapeutic program included various modules such as cognitive and grief therapy, reminiscence therapy, social skills and remotivation therapy. Analyses of pre-post measures of selected variables showed that the program was effective in improving the health status of the participants. As compared to a non-treatment control group, the elderly in the experimental group showed significant improvements in depression, social network, and a sense of control over their lives. A discussion of these findings is provided.

Black or African American↗

PubMed1990

Somatotropin treatment for a second consecutive lactation.

Twenty-five Holstein cows were used to examine effects of recombinant bST administration for a second successive lactation on milk yield and composition, BW change, body condition, and health. Treatments were 0 (physiological saline), 10.3, 20.6, and 33 mg bST/d (8, 8, 7, and 3 cows per treatment, respectively). Saline and bST were given daily as subcutaneous injections beginning 4 to 5 wk postpartum and continuing for 38 wk. Somatotropin increased 3.5% FCM yield linearly from 8 to 36% over controls (control FCM was 30.1 kg/d). Milk composition was not affected by bST except that milk from cows given the 10.3-mg dosage had slightly higher Ca and P contents than did milk from cows receiving 0 or 20.6 mg. Cows receiving bST were 9 to 30% more efficient than controls in converting feed to milk. Body weight gain was unaffected by treatment. Average condition score was unchanged for control cows during the first 84 d following initiation of treatment, but declined in cows given bST. Thereafter, condition score increased in a similar manner for all groups. No treatment-related patterns were found in incidence of mastitis, feet and leg problems, ketosis, or milk fever. Blood hormone, chemistry, and hematology revealed no effects of bST treatment other than to raise plasma bST concentrations. Under conditions of this experiment, use of bST during a second consecutive lactation did not change the normal physiology or productive capacity of lactating cows.

Animal Feed↗

PubMed1989

Evaluation of white lupines and triticale in calf starter diets.

One hundred fifty-two Holstein calves were used to evaluate white lupines (Lupinus albus cv. Ultra) and triticale in starter diets. The basal diet contained corn, oats, minerals, and vitamins. Starter components were 1) 14% soybean meal; 2) 10% soybean meal and 27% triticale; 3) 22% lupines; 4) 16% lupines and 24.5% triticale; 5) 11% lupines and 8% soybean meal; and 6) 7% lupines, 5% soybean meal, and 26.5% triticale. Dietary CP was approximately 16% of DM. Data collection began on d 4 after birth and continued through d 56. Calves were fed 3.6 kg of fermented colostrum from d 4 to 14 and 4.5 kg of fermented whole milk from d 15 to weaning at d 28. Starter diets and water were offered for ad libitum consumption from d 4 to 56. Dietary treatment had no effect on starter intake or weight gains. Average total gains during the experimental period were 25.6, 23.0, 23.3, 23.2, 25.0, and 21.6 kg for treatments 1, 2, 3, 4, 5, and 6, respectively. Calf health was excellent. Starter diets were examined in a dual flow continuous culture system to evaluate fermentation by rumen bacteria. Digestibilities of DM, organic matter, and total nonstructural carbohydrate did not differ among treatments. Ammonia N concentrations ranged from 11.9 to 13.8 mg/100 ml effluent. Chemical composition of bacteria, efficiency of bacterial protein synthesis, total VFA concentration in the effluent, and amino acid flow were similar for all treatments. The results indicate that lupines and triticale are satisfactory for use in calf starters when included in amounts equal to or less than those used in this experiment.

Animal Feed↗

PubMed1989

Health care behavior among urban black and white women.

A cohort of 308 black and white women was followed 6 years to determine health status and preventive health behavior. The women of both races had nearly identical age and education levels. Health care utilization and health state perception was nearly identical, too. White women more frequently were dieters while black women walked for exercise and used prayer for problem solution. Women who exercised initially felt better at the end of the study. The persistence of health activities was stronger for white women but over half never exercised. More women need engagement in consistent preventive health activities

Adult↗

PubMed1988

Effects of recombinant bovine somatotropin on milk production, body composition, and physiological parameters.

Twenty-eight multiparous Holstein cows were utilized to determine effects of long-term administration of recombinant bovine somatotropin on lactational performance, body condition, body composition, hormones, blood constituents, and physiological parameters. Treatments were 0 (control), 10.3, 20.6, and 41.2 mg recombinant bovine somatotropin administered daily as subcutaneous injections beginning 4 to 5 wk postpartum and continuing for 38 wk. A total mixed diet of 28% corn silage, 22% alfalfa hay cubes, and 50% corn-soybean meal-based grain mixture was fed. Fat-corrected milk yields were increased 12 to 25% for cows treated with somatotropin as compared with controls (29.9 kg/d). Milk composition was similar among treatments. Cows receiving somatotropin consumed 4 to 10% more feed and were 11 to 17% more efficient than controls for conversion of feed to milk. Body weight changes were not significantly different among treatments, but cows receiving somatotropin gained 4 to 10% less weight than controls. Body fat (kg) of cows receiving 20.6 and 41.2 mg/d was less than that of cows receiving 10.3 mg/d or no somatotropin. Estimated weights of body protein and mineral, most blood constituents, respiratory rates, and body temperature were not affected by somatotropin administration. Plasma fatty acids were elevated and hematocrit values were reduced. Plasma insulin, serum somatotropin, and heart rate increased concurrently with somatotropin administration.

Animals↗

PubMed1987

Comparison of sweet white lupin seeds with soybean meal as a protein supplement for lactating dairy cows.

Data were from 45 Holstein cows (23 multiparous, 22 primiparous) assigned by calving date and parity within groups to one of two isonitrogenous (16% crude protein) diets. The diets were 50% forages (corn silage, alfalfa silage) and 50% concentrate, dry basis. In diet A, soybean meal supplied 34.2% of total crude protein; in diet B, ground sweet white lupin seeds provided 37.9% of total crude protein. Cows were fed once daily during the experimental period (d 4 to 116 postpartum). Cows fed lupins consumed significantly less dry matter, produced 1.8 kg/d less milk (but not significantly different), and had lower milk protein percent. Milk fat and total solids percents were similar. Reasons for reduced intake of cows fed lupins were not evident. Traces of alkaloids (.005% dry basis) were present in diet B. Combined results of in vitro continuous culture fermentation and in situ degradation measurements indicated that crude protein from lupins was more degradable than that of soybean meal. Poor performances of cows fed lupins could be partly due to a reduced true protein supply to the small intestine.

Animal Feed↗

PubMed1986

Influence of formaldehyde-treated soybean meal on milk production.

Forty-eight Holstein cows were fed one of four diets containing 12.5% crude protein (negative control); 15.5% crude protein with untreated soybean meal; 15.5% crude protein with formaldehyde (.3%)-treated soybean meal; or 18% crude protein (positive control). Diets were 60% concentrate, 22% corn silage, 14% alfalfa hay, and 4% beet pulp (dry matter). Data were collected during the first 200 d of lactation. Dry matter intake, milk, and milk component yields did not differ among cows fed the untreated soybean meal, treated soybean meal, and positive control diets. Cows fed negative control diet consumed less dry matter and produced less milk than cows fed the other diets. Milk protein yield was lower for cows fed the negative control diet compared with the other diets. Nonprotein nitrogen content of milk increased as dietary protein increased.

Animal Feed↗

PubMed1985

Chronic medical problems, coping resources, and depression: a longitudinal study of rural Tennesseans.

This analysis examined chronic medical problems as a risk factor for depressive symptomatology using longitudinal survey data from a sample of rural Tennesseans. Two waves of data (1977 and 1983) were collected on 532 rural Middle-Tennessee residents. An initial investigation found chronic medical problems a powerful predictor of depression. Furthermore, internal and external resources (personal resources and social support) operated as moderating factors between the stress of medical problems and psychiatric impairment. Panel regression analyses indicated that Time 1 depression level as well as medical problems at Time 2 (t2) were significant predictors of depression at t2 in rural areas of the mid-South. Finally, the buffering effects of both social support and personal resources were explored.

Adaptation, Psychological↗

PubMed1985

Influence of methionine hydroxy analog and DL-methionine on rumen protozoa and volatile fatty acids.

Three lactating Holstein cows with rumen cannulae were used in a 3 X 3 Latin square arrangement of treatments to study effects of methionine source on ciliated protozoa numbers and volatile fatty acid concentrations in the rumen. Cows were fed total mixed diets twice daily of 60% grain mix, 21% corn silage, and 19% alfalfa hay (dry basis). Methionine hydroxy analog, DL-methione, and sodium sulfate were added on an equal sulfur basis. Experimental periods were 14 d with four rumen samples taken daily on d 13 and 14. Total ciliated protozoa were higher when cows were fed DL-methionine than when fed methionine hydroxy analog or sodium sulfate. Ruminal concentrations of butyric acid and isobutyric acid were higher for the DL-methionine treatment than for analog or sodium sulfate treatments. Isovaleric acid concentrations were also higher in fluid from cows fed methionine compared with cows fed the analog.

Animals↗

PubMed1985

Influence of three concentrations of DL-methionine or methionine hydroxy analog on milk yield and milk composition.

Sixty-eight Holstein cows were fed diets consisting of 60% concentrate and 40% forage, dry basis. Diets were supplemented with DL-methionine or methionine hydroxy analog at either 0, .1, .2, or .3% of the concentrate. Dietary protein averaged 14% of total dry matter on all diets except for a positive control diet, which was 19% crude protein. Data were collected beginning 4 d postpartum and continued through 116 d postpartum. Milk yield was not influenced by either DL-methionine or methionine hydroxy analog. Supplementation with DL-methionine resulted in a quadratic response in milk fat percentage (3.34, 3.58, 3.72, 3.42) at 0, .1, .2, and .3% of the concentrate, respectively. Milk fat percentage increased linearly (3.34, 3.64, 3.60, 3.73) with supplementation of methionine hydroxy analog at 0, .1, .2, and .3%, respectively.

Animal Feed↗

PubMed1985

Dilute sodium hyaluronate (Healon) in the treatment of ocular surface disorders.

The use of dilute (1/10%) sodium hyaluronate (Healon) eyedrops has given definite subjective patient improvement in a variety of ocular surface disorders, especially keratitis sicca. No adverse effects of the sodium hyaluronate drops have been encountered in patients who have used the drops for as long as two years. Masked trials and objective improvement of corneal staining patterns have also confirmed its efficacy.

Contact Lenses↗

PubMed1984

Bilateral massive ovarian edema. A case report.

Massive ovarian edema is a benign, tumorlike condition. It primarily involves the right ovary, and bilateral occurrence is rare. The fourth reported case of bilateral massive ovarian edema demonstrates that a methodical approach to the diagnosis of ovarian masses and conservative management of even bilateral massive ovarian edema are important.

Adolescent↗

PubMed1983

Influence of dietary energy and protein on yield and composition of milk from cows fed methionine hydroxy analog.

In three trials in consecutive years, 45, 59, and 63 lactating Holstein cows were fed grain mixtures containing either 0 or .25% methionine hydroxy analog with or without protein supplement. In Trial 1, diets were approximately 40% concentrate, and dietary protein averaged 13.2 and 15.8% (dry). Ration dry matter consisted of either 40 or 60% concentrate, and dietary protein averaged 13.5 or 17.3% in Trial 2 whereas concentrate was maintained at 60% of dry matter in Trial 3 with dietary protein at either 13.0, 15.0, or 17.5%. In Trial 1, milk yield or composition did not differ with methionine analog or protein supplementation. Protein supplementation increased milk yield on the 60% concentrate diets in Trial 2, and methionine analog increased milk fat percentage on the 60% concentrate diets. Cows fed 17.5% crude protein in Trial 3 produced more milk than those fed the two lower protein diets. Methionine analog increased milk fat percentage, and this increase was consistent at each percentage of dietary protein. Data from 179 lactations were combined and analyzed for response milk yield and composition to methionine analog included at either 0 or .25 to .30% of grain mixtures in 60% concentrate diets. Cows fed methionine analog produced milk higher in fat content and yielded more total fat and fat-corrected milk than controls.

Animals↗

PubMed1983

Effects of moisture content of complete diets on feed intake and milk production by cows.

In two trials, 47 and 54 Holstein cows were fed diets containing ensiled forages, ensiled and dry forages, or diets of different moisture contents. In trial 1, diets were fed during a preliminary dry period, early lactation, late lactation, a second dry period, and a second early lactation. In trial 2, four diets identical except for moisture content (78, 64, 52, and 40% dry matter) were fed for the first 200 days of lactation. Substitution of dry hay for alfalfa silage increased dry matter intake during the first early lactation, whereas partial substitution of corn silage with straw did not affect intake during dry periods. Dry matter intake increased linearly as dry matter content of diet increased in trial 2. Neither milk production nor body weight were affected by treatment in either trial. Percentage total solids increased linearly as dry matter content of diet decreased in trial 2. Volatile fatty acids differed slightly, but no trends were consistent. No differences of daily chewing time were observed. From these trials, diets of less than 60 to 65% dry matter may reduce intake by lactating dairy cows.

Animals↗