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Biomedical subjects

C L Ferrell

Publications and source records attributed to C L Ferrell.

At least 73 records · Page 4Linked to original sources
PubMed1986

Effects of growth rate and compensatory growth on body composition in lambs.

Fifty lambs were used in a comparative slaughter experiment to determine the effects of growth rates and compensatory growth on body composition. The study consisted of a growing and a finishing phase. During the growing phase, lambs (20 to 30 kg) were fed three different concentrate levels (30, 50 or 70%) to gain at three different rates (slow, medium and rapid). The finishing phase was evaluated in two periods (early, 30 to 38 kg; late, 38 to 45 kg). All lambs received 70% concentrate diets during the finishing phase. Groups of five lambs were sacrificed at 20, 30, 38 and 45 kg fleece-free weights for whole-body chemical analysis. At 30 kg live weight, lambs on a rapid growth diet were the fattest (P less than .01) and contained the least protein (P less than .05) in their empty bodies. The slower the lambs gained during the growing phase, the greater (P less than .05) was the response in rate of gain and feed efficiency during both periods of the finishing phase. Compensatory growth occurred in two stages; a greater proportion of protein gain was made early while a greater proportion of the fat gain was made during the late period of the finishing phase.

Animals↗
PubMed1985

Assessment of interrelationships among levels of intake and production, organ size and fasting heat production in growing animals.

Although the concept of metabolic body size (kg0.75) has gained widespread use in the field of energy metabolism, its application to the growing animal has been questioned. Fasting heat production, or maintenance, rather than being a constant function of body size, has been shown to vary because of breed, sex, condition, physiological state, production level, nutrition level and environmental conditions. Data are presented to show that fasting heat production and maintenance vary with nutritional level or rate of growth in animals postweaning. Variation in these energy expenditures are related to variation in weight of metabolically active internal organs. Weights of liver and gut and fasting heat production are shown to be functions of body size and level of production. More information is needed to ascertain the primary components of energy expenditures in animals and to quantitatively relate these components to animal energy metabolism.

Animal Nutritional Physiological Phenomena↗
PubMed1985

Transplacental diffusion and blood flow of gravid bovine uterus.

Electromagnetic blood flow transducers and uterine arterial, uterine venous, umbilical venous, fetal femoral arterial, and fetal femoral venous catheters were implanted in 11 cows on day 161 +/- 4 of gestation. Antipyrine (0.66 M) plus NaCl (0.16 M) dissolved in deuterium oxide (D2O), or H2O, was infused at a constant rate into the fetal femoral vein catheter. Concentrations of antipyrine and D2O in uterine arterial and venous blood and antipyrine in fetal arterial and umbilical venous blood, as well as middle uterine arterial blood flow (electromagnetic transducer), were determined. Antipyrine and D2O gave similar estimates (steady-state diffusion method) of gravid uterine blood flow. In addition, the slope of the regression of D2O on antipyrine estimates was not different (P greater than 0.10) from one. Electromagnetic transducers gave estimates of uterine blood flow that were 32-42% of those obtained with steady-state diffusion but were correlated (P less than 0.05) with estimates obtained by use of both antipyrine and D2O. The transplacental clearance rate of antipyrine was similar (per kg placenta) to that observed in ewes. It was suggested that the maternal and fetal microvasculatures of the bovine placenta could have a concurrent arrangement with vascular shunts or maldistribution of flows, as has been suggested for the ewe.

Analysis of Variance↗
PubMed1985

Cow type and the nutritional environment: nutritional aspects.

Numerous studies have been reported that relate to the influence of cattle type on production efficiency; however, most reported studies have been concerned with output characteristics. This review concentrates on the influence of cattle type on the input requirements and more specifically, energy requirements. Data are presented that show that energy is required for maintenance, growth, gestation and lactation and requirements for each of these functions vary among cattle types. Data are presented that suggest 70 to 75% of total annual energy requirements are required for maintenance functions and variation in requirements for maintenance appear to be greater than variation in requirements for growth, gestation or lactation. In general, variation in maintenance requirements appears to be positively associated with genetic potential for measures of production, e.g., rate of growth or milk production. Reported results suggest that animals having genetic potential for high productivity may have less advantage or be at a disadvantage in a more restrictive environment, suggesting the need for synchronization of production environment and germ plasm resources. Some of the sources of variation in maintenance requirements have been discussed. Data are cited that suggest little of the variation in maintenance energy expenditures is attributable to variation in total body composition per se. However, considerable evidence has accumulated to show that a relatively large proportion of maintenance energy expenditures can be attributed to energy expenditures of visceral organs, especially the liver and gastrointestinal tract. High rates of energy expenditures of these tissues appear to be directly or indirectly associated with the high rates of protein synthesis in these tissues. Greater use of differing research approaches and assimilation of the results are needed to develop an understanding of the reasons for variation among animals in maintenance energy expenditures or energetic efficiency.

Animal Feed↗
PubMed1985

Blood flow and steroid and nutrient uptake of the gravid uterus and fetus of sows.

Uterine and umbilical blood samples and blood flow (BF) measurements were obtained from one uterine horn and a single fetus of sows at d 70, 90 and 110 of gestation. Concentrations of O2 in blood and of estrogen (E), progesterone (P), glucose, alpha-amino nitrogen (N) and urea N in plasma were determined. Fetal weights were .267 +/- .018, .633 +/- .019 and 1.208 +/- .073 kg on d 70, 90 and 110, respectively. Uterine and umbilical BF remained constant with day of gestation, averaging 1.51 +/- .06 and .31 +/- .02 liters/min. Uptake of P by a uterine horn and fetus remained constant, but secretion of E by a uterine horn and uptake of E by a fetus increased (P less than .05) with stage of gestation. Uterine and fetal uptake of O2, glucose and alpha-amino N did not change and uptake of O2, glucose and alpha-amino N per kg fetus decreased (P less than .01) as gestation advanced. Secretion of urea N from the uterus was observed, with a concentration gradient from the fetal to the uterine circulations. Uterine and fetal respiratory quotients for glucose were .79 and .38, respectively. Thus, although glucose potentially served as a major energy source, a large portion of the energy requirements of the fetal pig were met by catabolism of other substrates. The decrease in umbilical BF and uptake of nutrients per kg fetus with day of gestation suggested that porcine fetal metabolism declined as pregnancy advanced.

Amino Acids↗
PubMed1984

Interrelationships among diet, age, fat deposition and lipid metabolism in growing steers.

Subcutaneous adipose tissue samples were obtained by biopsy technique and at slaughter from steers fed either a corn concentrate or pelleted alfalfa (roughage) diet. Steers fed the roughage diet had slightly greater metabolizable energy intakes than the concentrate-fed steers due to greater rates of feed intake; however, steers fed the concentrate diet had faster rates of gain, primarily in the fat depots. Diet had no effect on the incorporation of 14C-labeled acetate and lactate into fatty acids, although 3H2O incorporation into fatty acids was greater in the concentrate-fed steers. Although backfat thickness was 60% greater in the concentrate-fed steers, the number of adipocytes per gram adipose tissue was unaffected by diet, suggesting adipose cell hyperplasia. The activities of acetyl-CoA carboxylase, fatty acid synthetase, ATP citrate lyase, NADP+ malate dehydrogenase, and hexokinase were greater in the steers fed the concentrate diet; pyruvate kinase activity was unaffected by diet. Fatty acid synthesis and several lipogenic enzyme activities increased with age and then declined markedly by the time of the terminal biopsy. Basal and net rates of lipolysis generally were unaffected by diet but increased with age of the animal. As the animals gained weight, the ratio of net fatty acids released to glycerol released decreased, suggesting more extensive reesterification of fatty acids released during lipolysis.

Adipose Tissue↗
PubMed1984

Relationships among various body components of mature cows.

Mature (9-yr-old), nonpregnant, nonlactating Angus X Hereford and the reciprocal cross (AHX, 12), Charolais X Angus or Hereford (CX, 11), Jersey X Angus or Hereford (JX, 11) and Simmental X Angus or Hereford (SX, 12) cows that had been fed either a low (112 kcal X kg-.75 X d-1), medium (178 kcal X kg-.75 X d-1) or high (ad libitum) level of metabolizable energy (ME) intake for 140 d were used to evaluate relationships among various body components. Live weight, hip height, backfat and condition score were determined on d 140. Before slaughter, each cow was infused with deuterium oxide (D2O; .25 g/kg live weight) and serial blood samples were taken. Traits evaluated after slaughter were hot weight of each carcass half, hide weight, viscera weight, longissimus muscle area, fat thickness, kidney, pelvic and heart fat percentage and marbling score. Offal and carcass chemical compositions were determined and empty body composition was calculated. Moderate to high (R2 = .82 to .97) coefficients of determination were obtained when weight of empty body chemical components were regressed on live animal or carcass cooler measures. Correlations between percentage carcass or empty body water and percentage of fat, fat-free organic matter or energy, or between amount of carcass or empty body water and amount of fat-free organic matter were high (R2 = .83 to .99). Weight of carcass or empty body water was not highly related (R2 = .05 to .22) to the total amount of fat or energy. Similar results were obtained when amount of empty body components were regressed on D2O spaces alone. Inclusion of empty body weight (or live weight) in equations relating D2O spaces to weight of the empty body or chemical components resulted in R2 values of .86 to .99. Carcass composition, as expected, was more highly related to empty body composition than was offal composition. Empty body composition was not highly related to empty body weight.

Adipose Tissue↗
PubMed1984

Energy utilization by mature, nonpregnant, nonlactating cows of different types.

Four types of crossbred cows were used in each of two studies designed to estimate the metabolizable energy (ME) required to maintain weight or energy equilibrium of mature (9-yr-old), nonpregnant, nonlactating cows. The four cow types were chosen to represent cow types having moderate mature size-moderate milk production potential (Angus X Hereford, Hereford X Angus; AHX), large mature size-moderate milk production potential (Charolais X Angus or Hereford; CX), small mature size-high milk production potential (Jersey X Angus or Hereford; JX) and large mature size-high milk production potential (Simmental X Angus or Hereford; SX). In each of two consecutive years, four cows of each type were assigned randomly and fed individually either a low (113 kcal ME X kg-.75 X d-1), medium (178 kcal ME X kg-.75 X d-1) or a high (ad libitum) level of a corn silage-based diet for 140 d. Body composition of each cow was estimated by deuterium oxide dilution techniques at d 0 and 140 of each study and gains were calculated. The ME required to maintain weight or energy equilibrium was estimated for each type of cow. Estimates of ME required to maintain energy equilibrium (from the regression of log heat production, kcal X kg-.75 X d-1 on ME intake kcal X kg-.75 X d-1) were 130, 129, 145 and 160 kcal X kg-.75 X d-1 for AHX, CX, JX, and SX cows, respectively. Similar trends were observed when other models were used. Cow types with higher milk production potential had higher maintenance (kcal X kg-.75 X d-1) than cows with lower milk production potential. Cows of larger size had maintenance requirements (kcal X kg-.75 X d-1) similar to those of smaller size. Possible reasons for these differences as well as their potential impact on cow efficiency are discussed.

Animals↗
PubMed1984

The effects of body composition on fasting heat production in pigs.

Ten sets of three litter mate barrows from each of three genetic stocks, Beltsville Highfat (HF) and Lowfat (LF) Duroc-Yorkshire composites and a Hampshire X Large White cross (CX), were used to investigate effects of body composition on fasting heat production (FHP). Pigs from each set were fasted for 24 h at 10, 17 or 24 wk of age before measuring respiratory exchange for 24 h in an open-circuit calorimeter. Average heat production during night hours (8 h) in the calorimeter was used to estimate FHP. Each pig was then slaughtered and dissected into three fractions: carcass, head and feet, viscera and blood. Each fraction was frozen, ground, sampled and analyzed for protein, fat, water and ash. Correlations within ages of FHP with calorimeter live weight (CLWT) were lower than with total weight of lean, protein or water, but near zero with fat at all ages. Coefficients of determination (R2) for linear and nonlinear predictors of FHP from lean were: .58, .89 and .91 at 10, 17 and 24 wk, respectively, but from CLWT were: .52, .74 and .82, respectively. Negative partial regressions of FHP on fat improved R2 slightly at 10 and 17 wk but not at 24 wk, suggesting that fatter pigs were better insulated. Viscera and blood influenced FHP more than carcass or head and feet. Estimated exponents relating lean mass to FHP ranged from .79 to .86 and FHP (kcal/d) = (86 +/- 20) X lean kg X 84 (+/- X 06) at 24 wk. There was some evidence of stock differences in FHP independent of body composition.

Adipose Tissue↗
PubMed1984

Effects of breed and intake level on growth and feed efficiency in ram lambs.

Effects of breed and intake level on growth and feed efficiency in ram lambs were tested with 52 Rambouillet, 46 Dorset and 53 Finnish Landrace (Finn) rams. Rams were individually fed at 100, 85 or 70% of ad libitum or at maintenance. The experimental diet contained 79% digestible dry matter (DM), 3.28% N and 2.95 Mcal metabolizable energy/kg DM. Rams were serially slaughtered every 35 d for 175 d. The efficiency of deposition of body weight, protein, energy and trimmed cuts was determined by breed and intake level over constant time, weight, fat and maturity intervals. Ranking of the breeds for feed efficiency depended upon both the interval and the criterion of evaluation. Efficiency of protein and trimmed cut gain was positively related to mature size in the time and weight intervals, but all differences in efficiency were small in the fat or maturity intervals. Gross energetic efficiency did not differ greatly among breeds in any interval. Dorsets appeared to have a somewhat greater propensity to fatten than the other breeds and to be less able to retain N at a fixed N intake. In the constant time interval, maintenance requirements were estimated to be 115 kcal/kg.75, and the estimated partial efficiencies of energy deposition in fat and protein were .49 and .26, respectively.

Animal Feed↗
PubMed1984

Estimation of body composition of pigs.

A study was conducted to evaluate the use of deuterium oxide (D2O) for in vivo estimation of body composition of diverse types of pigs. Obese (Ob, 30) and contemporary Hampshire X Yorkshire (C, 30) types of pigs used in the study were managed and fed under typical management regimens. Indwelling catheters were placed in a jugular vein of 6 Ob and 6 C pigs at 4, 8, 12, 18 and 24 wk of age. The D2O was infused (.5 g/kg body weight) as a .9% NaCl solution into the jugular catheter. Blood samples were taken immediately before and at .25, 1, 4, 8, 12, 24 and 48 h after the D2O infusion and D2O concentration in blood water was determined. Pigs were subsequently killed by euthanasia injection. Contents of the gastrointestinal tract were removed and the empty body was then frozen and later ground and sampled for subsequent analyses. Ground body tissue samples were analyzed for water, fat, N, fat-free organic matter and ash. Pig type, age and the type X age interaction were significant sources of variation in live weight, D2O pool size and all empty body components, as well as all fat-free empty body components. Relationships between age and live weight or weight of empty body components, and between live weight, empty body weight, empty body water or D2O space and weight of empty components were highly significant but influenced, in most cases, by pig type. The results of this study suggested that, although relationships between D2O space and body component weights were highly significant, they were influenced by pig type and were little better than live weight for the estimation of body composition.

Age Factors↗
PubMed1984

Blood flow, steroid secretion and nutrient uptake of the gravid uterus during the periparturient period in sows.

Blood flow to one uterine horn of six Yorkshire sows was measured daily from d-22 to 0 (d of parturition) using an electromagnetic blood flow transducer surgically implanted around the middle uterine artery. Immediately after measurement of uterine arterial blood flow (UABF), samples of femoral arterial (FA) and uterine venous (UV) blood were collected via indwelling catheters and concentrations of progesterone, estrone and estradiol-17 beta, oxygen, glucose, total alpha-amino acid N and urea N were determined. Throughout the experimental period, sows were maintained in farrowing stalls. Surgical procedures used in this study had no effect on length of gestation, litter size, number of live piglets born or average weight of live piglets when compared with noninstrumented littermate controls. The UABF remained constant from d-22 through -1, then declined dramatically on the day of parturition with delivery of the fetuses and placentae. Concentration of progesterone in FA and UV blood of sows remained constant from d-22 to -3, but was higher (P less than .01) in FA (12.68 +/- .48 ng/ml) than in UV (7.56 +/- .20 ng/ml) blood. Progesterone concentrations in FA and UV blood began to decline 2 d before parturition to reach low levels on d 1. Estrone and estradiol-17 beta concentrations were greater (P less than .01) in UV than in FA blood, and increased progressively from d -22 to reach peak levels on d -4 through -1 which averaged 7,245 +/- 655 and 1,001 +/- 88 pg/ml in UV blood and 3,923 +/- 157 and 547 +/- 35 pg/ml in FA blood, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Nutrient requirements to maintain weight of mature, nonlactating, nonpregnant cows of four diverse breed types.

Four breed types with 12 cows/breed-type (Hereford x Angus, AHx; Charolais and Angus and Charolais x Hereford, Cx; Jersey x Angus, Jersey x Hereford, Jx and Simmental x Angus, Simmental x Hereford, Sx) were used to estimate nutrient requirements for zero daily weight change. Four nonpregnant, nonlactating cows of each breed type were assigned to one of three feeding levels [90 kcal metabolizable energy (ME).kg body wt (kg)-.75 . d-1, 150 kcal ME.kg-.75.d-1 and ad libitum] for a 140 d feeding period. The feeding trial was: Period 1 (d 0 to 70) and Period 2 (d 70 to 140). Effect of breed type, feeding level and the two-way interaction upon weight, weight change and feed intake data were initially analyzed. Two-factor interactions tended not to be significant for weight and weight change. The main effects of breed type and feeding level tended to be significant for weight and weight change in each of the periods. On d 0, the Sx (570 +/- 13 kg) and Cx (578 +/- 14 kg) were heavier (P less than .05) than the AHx (527 +/- 13 kg) all of which were heavier than the Jx (458 +/- 14 kg). Under the two restricted diets, the breed type ranking for dry matter intake corresponded to the ranking for initial body weight. However, at the ad libitum feeding level, the Cx tended to consume less dry matter than the other breed types. Measures of weight change were evaluated to test the effect of breed type and dry matter intake. The effect of breed type was significant only for daily weight change (kg/d) during Period 2. The linear and(or) quadratic effects of dry matter intake (2.53 Mcal ME/kg dry matter) on measures of weight change were significant in all periods. During Period 1, the pooled dry matter intake estimate for zero daily weight change and zero metabolic weight change were 8.1 kg/d and 75.3 g.kg-.75.d-1, respectively. For AHx, Cx, Jx and Sx during Period 2, daily dry matter intake for zero weight gain was 4.2, 5.3, 4.2 and 5.5 kg/d, respectively. A pooled estimate of 43.9 g . kg-.75 . d-1 was obtained for dry matter intake relative to metabolic size in Period 2.

Animals↗
PubMed1982

Influence of pre- and post-partum nutrition on LH secretion in suckled postpartum beef heifers.

The influence of nutrition during the last trimester of pregnancy and the early postpartum period on postpartum LH secretion was evaluated in two-year-old Hereford and Simmental heifers maintained on a high or low plane of nutrition (experiment 1) or in Hereford heifers fed a high or low energy (150% vs 100% NRC) ration (experiment 2). Amount of LH released with 10 mg estradiol benzoate (IM) at 14 and 28 days postpartum in experiment 1 or at 14,32,50 and 74 days postpartum in experiment 2 was less (P<.01) for heifers fed the low vs high plane or energy ration and less (P<.05) at 14 days postpartum than at subsequent postpartum periods. The interval from estradiol benzoate injection to the LH peak concentration was longer (P<.05) in Simmental than Hereford heifers, longer (P<.05) in heifers fed the low rather than high energy ration, and longer (P<.01) at 14 days postpartum than at subsequent postpartum periods. The amount of LH released was inversely related to the time required for initiation of the release (r = -.62). Tonic LH secretion was higher (P<.05) in heifers fed the high energy ration and was correlated with average daily gain (r = .75), but was unaffected (P.05) by days postapartum or breed of cattle. Results indicate that increased dietary energy intake increases LH secretion and shortens the anovulatory period in suckled postpartum beef heifers.

Journal Article↗
PubMed1982

Bone lesions in growing swine fed 3% cement kiln dust as a source of calcium.

Cement kiln dust (CKD) samples of which have been reported to stimulate growth in cattle and sheep, was fed to weanling pigs in a 42-d experiment. CKD at levels of 1.5 and 3.0% was added to a corn-soybean meal-oats-whey-type diet containing inadequate amounts of Ca (.4% of the diet) to provide final dietary Ca levels of .85 and 1.3%. A diet containing 3% limestone (1.3% dietary Ca) served as a positive control. Body weight gain was depressed by 3.0% CKD, and histopathological lesions of the humerus, not typical of nutritional secondary hyperparathyroidism or rickets, were observed. The lesions detected were osteonecrosis, thinning of the cortex and reduction in the width of the epiphyseal cartilage. Width of the proximal epiphyseal plate and cortical index of the humerus (width of cortex divided by total diameter at narrowest point of diaphysis) were smaller in pigs fed 3% CKD than in pigs fed 3% limestone. CKD contained 2.3% A1, 15 ppm Cd and 110 ppm Pb, providing 690, .45 and 3.3 ppm of A1, Cd and Pb, respectively, in the diet containing 3% CKD. Kidney, liver and bone ash concentrations of these three minerals were not increased by CKD, and typical toxicity signs were absent. It is concluded that CKD may contain one or more factors that interfere with normal bone metabolism in growing pigs when the diet contains 3.0% CKD.

Animals↗
PubMed1982

Mineral accretion during prenatal growth of cattle.

Angus, Hereford and Red Poll crossbred yearling heifers (n = 81) were mated to Brown Swiss bulls. Pregnant heifers were assigned on the bases of weight and breed cross to one of three diets and fed to achieve maternal weight gains of 0, .5 or 1.0 kg/d. Heifers from each treatment group were slaughtered at about 120, 150, 180, 210, 240, or 255 d postmating. Reproductive tracts were recovered at slaughter. Weights of the gravid uterus, fetus, fetal membranes, fetal fluids, uterus, cotyledons and placenta were obtained and have been reported previously. Fetuses were frozen and later ground, mixed and sampled. Dry matter was determined. Samples of each fetus were ashed, and concentrations of Ca, P, Na, K, Mg, Fe and Zn were determined. Relationships between total fetal content of each mineral and day postmating were obtained, and daily fetal accretion rates of each mineral were estimated for several stages of gestation. Daily requirements and allowances of each mineral for pregnancy in beef cows were estimated. Estimated allowances for Ca, P, Na, K, Fe and Zn were small during early gestation but increased rapidly and reached maxima of 8.4 g, 5.2 g, .76 g, .63 g, 65 mg and 21 mg, respectively, at about 250 d postmating.

Animals↗
PubMed1982

Effects of postweaning rate of gain on onset of puberty and productive performance of heifers of different breeds.

Angus, (n = 78), Hereford (93), Red Poll (61), Brown Swiss (47), Charolais (36) and Simmental (90) heifers were used in a study designed to evaluate the effects of breed and postweaning rate of gain (low, L = .4 kg/d; medium, M = .6 kg/d; high, Hi = .8 kg/d) on the onset of puberty and subsequent maternal performance. After a 184 d feeding period, one-half of the heifers in each group were moved to pasture and one-half were kept in the feedlot through breeding (70 d), then moved to pasture. Breeds differed (P less than .01) in weight, height and condition. Increased postweaning rates of gain resulted in increased heifer weight (P less than .01), height (P less than .10) and condition (P less than .01) before calving (198 to 635 d) but these differences were not observed after rebreeding (930 d). Quadratic regressions of percentage pubertal vs age were significantly influenced by the interaction between breed and postweaning rate of gain. Both mean age and weight at puberty were influenced by breed (P less than .01) and postweaning rate of gain (P less than .01). No interactions were observed (P greater than .10). Calf birth weight was influenced (P less than .01) only by breed. Milk production was influenced by breed (P less than .01) and postweaning rate of gain (P less than .10). Significant time after parturition and time X breed interaction effects on milk production were observed. Calf weight at 120 d and at weaning was influenced by breed (P less than .01), heifer postweaning rate of gain (P less than .05) and sex (P less than .05). These data suggest moderate underfeeding or overfeeding during the postweaning period may have a prolonged influence on the productive performance of heifers and demonstrate that breeds differ widely in age at puberty and later productivity under the type of management and environment of this study.

Animals↗