Journal of Animal Science

DiCostanzo,, A.;Meiske, J., C.;Plegge, S., D.

doi: 10.2527/1991.6941337xpmid: 2071497

Abstract Dry matter intake and BW data from 14 mature, nonpregnant, nonlactating Angus cows that were individually fed through two consecutive 70- to 80-d periods (maintenance and ad libitum) were used to predict ADG (ADG = -.512 + .213 DMI − .0017 BW, R = .95). This equation then was used to identify feed efficiency types among these cows. Cows were identified as average type (A) if ADG was within one SE of predicted ADG, and as efficient (E) or inefficient types (I) if ADG exceeded one SE above or below, respectively, its predicted ADG. Four, four, and six cows were identified and grouped as I, A, and E types, respectively. During the maintenance period, DM and ME intake and ADG were similar (P > .10) across all three efficiency types. But during the ad libitum period, voluntary DM and ME intakes of I cows were greater (P < .05) than those of A or E cows. Average daily gains of I cows during ad libitum feeding were greater (P < .10) than those of A cows. Daily ME required for maintenance of I cows was highest, that of A cows was intermediate, and that of E cows was lowest (180.2, 154.6, and 135.1 kcal/kg BW.75, respectively). Inefficient cows tended (P > .10) to have less fat and deposited more protein (P < .05) than A and E cows (137.9 vs 77.2 and 46.2 protein g/d, respectively). Concurrent with higher protein accretion rates, liver weights of I cows were heavier (P < .05) than those of A and E cows (8.58 vs 7.79 and 7.68 kg, respectively). Inefficient cows were characterized by higher energy requirements for maintenance. Their high protein accretion may partially explain their higher maintenance requirements. This content is only available as a PDF. Author notes 2 Present address: Dept. of Anim. Sci., Univ. of Missouri, Columbia, MO 65211. 3 Present address: Midwest-PMS, Inc., Gering, NE 69341. Copyright © 1991 by American Society of Animal Science

Wu, J., F.

doi: 10.2527/1991.6941349xpmid: 2071498

Abstract A comparative slaughter experiment was conducted to determine the energy values of cassava chips for weanling pigs. A basal, highly fortified diet was fed to all pigs at 3% body weight daily. Treatments consisted of the addition of cassava chips at 0,1, and 2% of body weight daily. The apparent digestion coefficients (ADC) for dry matter and energy increased but the ADC for nitrogen decreased with the addition of cassava chips to the basal diet. Digestible energy per gram decreased linearly and quadratically (P < .01), but metabolizable energy and net energy per gram remained constant with the addition of cassava chips. Metabolizable energy as a percentage of digestible energy increased linearly and quadratically (P < .01) with the addition of cassava chips to the basal diet. Daily gain of nitrogen, ether extract, and energy increased linearly (P < .01) as cassava chips were added to the basal diet, but daily gain of ash remained relatively constant. Pooled energy values determined for cassava chips in kcal/g of dry matter were: gross energy, 4.04; digestible energy, 3.58; metabolizable energy, 3.48; nitrogen-corrected metabolizable energy, 3.22; and net energy, 2.57. Net energy of cassava chips for weanling pigs is close to that of com. This content is only available as a PDF. Copyright © 1991 by American Society of Animal Science

Reynolds, L., L.;Brown, D., L.

doi: 10.2527/1991.6941354xpmid: 2071499

Abstract Two experiments were conducted to examine the milk producing ability of Western White-Faced sheep and to identify traits that correlate well with milk production. In Exp. 1, 31 Targhee ewes were milked and five samples were taken during 107-d lactations in which the ewes nursed twin lambs. Milk yield and composition, Iamb weights, ewe weights, wool growth, and udder size also were measured. In Exp. 2, 24 ewes (Rambouillet X Finn-Dorset) were separated from their lambs at 7 wk and milked twice per day for eight more weeks, during which milk yield and composition, feed consumption, udder width, and ewe weights were measured. Results from Exp. 1 showed that lamb 30-d weights, ewe weights at breeding time, and udder width at peak lactation were highly correlated with suckled milk yield (r = .81, .75 and .66, respectively). Results from Exp. 2 indicated that lamb weights and ewe weights were not useful for predicting milk yield in dairy ewes, but feed intake and udder width were (r = .74 and .86, respectively). Single-day milk yield measurements were excellent estimators of total lactation yield in both experiments. Milk yields averaged 1,714 g/d in the suckled ewes and 477 g/d in the dairy ewes. This content is only available as a PDF. Author notes 1 Depl. of Anim. Sci. Copyright © 1991 by American Society of Animal Science

Jones, S., J.;Johnson, R., D.;Calkins, C., R.;Dikeman, M., E.

doi: 10.2527/1991.6941363xpmid: 2071500

Abstract The objective of this study was to determine the effects of different implanting schemes on serum testosterone and Cortisol concentrations, and carcass traits of bulls and steers implanted with trenbolone acetate (TBA) and zeranol (Z). Twenty Polled Hereford bulls were randomly assigned to one of three treatments after birth. Five calves served as nonimplanted control bulls (NIB). Nine bulls were implanted (IB) with 140 mg of TBA and 36 mg of Z at about 1 mo of age and reimplanted with both compounds 10 wk later. When IB calves were about 21 wk of age, the TBA implant was removed and calves were reimplanted with Z every 10 wk until slaughter. Six calves were castrated at 3 wk of age and implanted (IS) with TBA and Z every 10 wk until slaughter. Blood samples from each animal were obtained at 14-d intervals beginning at 14 wk of age and serum Cortisol (C) and testosterone (T) concentrations were determined. The NIB had higher C levels than IB or IS (P < .05) during the preweaning period. During the finishing period, there were no differences in C concentrations between NIB and IB; however, IS had lower levels (P < .05) than both bull treatments. Serum T concentrations began to increase about 12 wk later (42 vs 30 wk, respectively) in IB compared with NIB. Testicular size was smaller (P < .05) in IB than in NIB. No differences (P > .05) were observed in carcass characteristics. Taste-panel scores were not different among treatments. In conclusion, implanting schemes using TBA and Z lowered serum levels of C and delayed puberty in bulls; however, they did not alter carcass characteristics or eating quality. This content is only available as a PDF. Author notes 2 Univ. of Nebraska, Dept. of Anim. Sci. 3 Kansas State Univ., Dept. of Anim. Sci. and Ind. Copyright © 1991 by American Society of Animal Science

Mahan, D., C.;Lepine, A., J.

doi: 10.2527/1991.6941370xpmid: 2071501

Abstract An experiment using a total of 210 crossbred pigs from two farrowing groups evaluated the effects of three weaning weights and their associative starter feeding program on subsequent postweaning performance to 105 kg BW. One group of pigs nursed their dams in outside heated hutches (Trial 1), and a second group was raised in a centrally heated farrowing house (Trial II). The three pig weaning weight groups ranged in weight from 1) 4.1 to 5.0 kg, 2) 5.5 to 6.8 kg, and 3) 7.3 to 8.6 kg. Pigs in Group 1 were fed a high nutrient dense diet (HNDD) for a 2-wk period followed by a corn-soybean meal-dried whey (C-SBM-DW) and then a com-soybean meal (C-SBM) diet, each for a 2-wk period. Group 2 was fed the same diet sequence except that the HNDD was provided for 1 wk, whereas Group 3 was provided only the C-SBM-DW and the C-SBM diets each for 2 wk, consecutively. At the end of the nursery period, pigs were fed C-SBM diet formulations to 105 kg BW. Pigs of Trial I averaged 5.2 d older at weaning than those raised in the central farrowing house, but only a 1.5-d difference existed between light- and heavy-weight groups in both trials. Gains and feed intakes for the three weaning groups were higher as weaning weight increased during both the nursery and the growing-finishing period. There did not seem to be a compensatory growth response for lighter-weight weanling pigs even though they had been fed starter diets containing milk products. Consequently, fewer days (-15) were required for the heavier-weight weanling pig group to reach a final weight of 105 kg than for the light-weight group. The medium-weight group required an intermediate number of days to reach 105 kg. This content is only available as a PDF. Copyright © 1991 by American Society of Animal Science

Brumm, M., C.;Shelton, D., P.

doi: 10.2527/1991.6941379xpmid: 2071502

Abstract Two experiments, each consisting of three trials and using 3- to 4-wk-old newly weaned pigs, were conducted to evaluate the effects of two reduced nocturnal temperature regimens on weaned pig and subsequent growing-finishing performance and nursery energy (propane and electricity) use. In Exp. 1, nursery treatments were 1) a control temperature (CT) regimen of 30°C constant air temperature lowered 2C7wk and 2) a regimen for pigs in pens with hovers (MRNT-H) in which the temperature from 1900 to 0700 beginning 1 wk after weaning was lowered 6C° from the 0700 to 1900 temperature setting, which was 3C° lower than CT. The nursery temperature treatments in Exp. 2 were 1) CT and 2) a 10C° reduction in air temperature (MRNT10) from 1900 to 0700 from CT beginning 1 wk after weaning. In addition, within each temperature, diet sequences of 1.2% lysine for 3 wk followed by 1.0% lysine vs 1.15% lysine offered continuously were evaluated. In Exp. 1, there was no effect (P > .1) of temperature on feed intake but ADG decreased (P < .001) in two of the three trials for MRNT-H vs CT and feed/gain worsened (P < .05) in all trials. In Exp. 2, there was no difference between MRNTIO and CT for ADG and feed/gain. No interaction was observed between nursery diet and temperature regimen for weaned pig performance. There was no effect (P > .1) in either experiment of nursery temperature on subsequent growing-finishing performance. Overall energy savings comparing the MRNT-H and CT treatments were 68 MJ per weaned pig. Energy savings for Exp. 2 were 79 MJ per weaned pig. Application of cyclical temperatures in a controlled manner can result in energy savings of approximately $.50 per pig weaned under the conditions of these experiments. This content is only available as a PDF. Author notes 2 The authors acknowledge the assistance of Dennis Forsberg with animal care and Jim Dahlquist and Kevin Fairbanks with data collection and analyses. 3 Dept. of Anim. Sci. 4 Dept. of Agric. Eng. 5 Northeast Res. and Ext. Center. Copyright © 1991 by American Society of Animal Science

Zinn, R., A.;Song, M., K.;Lindsey, T., O.

doi: 10.2527/1991.6941389xpmid: 2071503

Abstract A feedlot growth-performance trial and a metabolism trial were conducted to evaluate a dose response to ardacin (a glycopeptide antibiotic). Treatments consisted of an 88% concentrate finishing diet supplemented to contain (DM basis) 0, 8.25, 16.5., or 33 mg ardacin/kg. The growth-performance trial (129 d) involved 120 heifers and 120 steers in a randomized complete block design. There were no interactions (P > .10) between sex and response to ardacin. Average daily gain increased (P < .05) and DM conversion decreased (P < .01) with increasing levels of ardacin supplementation. At the 33 mg/kg level of supplementation, ADG and DM conversion were improved 10.6 and 5.6%, respectively. Four Holstein steers (344 kg) with cannulas in the rumen and proximal duodenum were used to evaluate treatment effects on characteristics of digestion. There were cubic effects of ardacin on ruminal starch digestion (P < .05), microbial N synthesis (MNS, P < .10), and microbial efficiency (MNEFF, grams of MNS/kilogram of OM fermented). For the 16.5 and 33 mg/kg levels of supplementation, ruminal starch digestion was increased 4.9%, and MNS and MNEFF were decreased 12.9 and 15.6%, respectively. Postruminal and total tract digestion of N increased linearly (P < .10) with ardacin supplementation. Total tract digestion of OM, ADF, and starch were not affected (P > .10). Ardacin did not influence (P > .10) ruminal pH or molar VFA proportions. It is concluded that supplementation of a finishing diet with 33 mg ardacin/kg will enhance ADG and DM conversion of feedlot steers and heifers. This content is only available as a PDF. Author notes 1 Anim. Sci. Dept, Imperial Valley Agric. Center. 2 SmithKline Beecham Anim. Health, West Chester, PA. Copyright © 1991 by American Society of Animal Science

Mahan, D., C.

doi: 10.2527/1991.6941397xpmid: 2071504

Abstract Two experiments involving a total of 581 crossbred pigs weaned at 23 ± 2 d of age evaluated 1) the efficacy of two diets that contained milk products during the initial 14 d postweaning and 2) the effect of coconut oil or soybean oil additions to swine starter diets. In Exp. 1, postweaning performance responses of pigs fed a control com-soybean meal-dried whey (C-SBM-DW) diet without added fat were compared with those of pigs consuming diets that contained 3, 6, or 9% levels of coconut oil or degummed soybean oil. The results demonstrated no beneficial weight gain, feed intake, or gain-to-feed ratio response during the initial 14 d postweaning to either dietary oil source. From 15 to 35 d, gains increased to the 6% added fat level, but there was no effect on feed intake when the gain-to-feed ratio was improved to the 9% fat level. In Exp. 2, two diets containing milk products were fed during the initial 14-d postweaning period The first diet contained com, soybean meal, dried whey, dried skim milk, and fishmeal (high nutrient dense diet, HNDD), and the second was a C-SBM diet with 25% dried whey. During the period from 15 to 35 d, diets contained no added fat or a 6% level of coconut oil, soybean oil, or the 1: 1 combination of each at 3%. The results demonstrated that for the postweaning period from 0 to 14 d pigs fed the HNDD had higher gains (P < .01), feed intakes (P < .01), and gain-to-feed ratios (P < .01) than pigs fed the C-SBM-DW diet.(ABSTRACT TRUNCATED AT 250 WORDS) This content is only available as a PDF. Copyright © 1991 by American Society of Animal Science

Bailey, C., M.;Reid, C., R.;Ringkob, T., P.;Koh, Y., O.;Foote, W., D.

doi: 10.2527/1991.6941403xpmid: 2071505

Abstract Feedlot and carcass traits of nulliparous and primiparous females representing eight breed types, including Bos taurus and Bos indicus X Bos taurus crosses, were evaluated. NuUiparous females (heifers) were in the feedlot for 4 mo; primiparous females (heiferettes) were fed for 2 1/3 mo after their calves were weaned at 6 mo of age. Heifers averaged higher (P < .01) in dressing percentage, percentage of kidney fat, carcass grade (P < .10), and color of lean (P < .05) compared with heiferettes. Heiferettes exceeded the nuUiparous group in feedlot ADG (P < .01), fat thickness (P < .05), and percentage of steak, roast, and bone (P < .01). Parity effects on carcass weight, longissimus area, marbling, pH, and shear force value were not statistically significant. Dam breed types differed in several traits, including marbling (P < .05) and percentage of steak (P < .10), roast (P < .01), and bone (P < .01). Dam breed x parity interactions were nonsignificant. Results show that beef derived from heiferettes is competitive with heifer beef. This content is only available as a PDF. Author notes 1 The authors are indebted to Don Albert and Edward Dunn for invaluable technical assistance. 2 Current address: Cooperative Extension Service, Box 69, Newcastle, WY 82071. Copyright © 1991 by American Society of Animal Science

Bullock, K., D.;Kuhlers, D., L.;Jungst, S., B.

doi: 10.2527/1991.6941409xpmid: 2071506

Abstract Duroc boars from a line previously selected over five generations for 200-d weight and those from a randomly selected control line were mated to Landrace sows either from a line previously selected for increased 70-d weight or from a randomly selected pedigree control line. From these matings, 900 pigs were farrowed to examine the effects of crossing lines of pigs mass selected for weight at two ages on growth rate, survival, and carcass composition. A greater (P < .01) percentage of pigs farrowed survived birth from control-line sows (.974) than from select-line sows (.914). Of those pigs born alive, a greater (P < .05) percentage of pigs out of control-line sows survived to 21 d (.893) than out of select-line sows (.829). Pigs sired by select-line boars weighed 2.1 kg heavier (P < .05) at 70 d than pigs sired by control-line boars. Pigs out of select-line sows weighed .11 kg less (P < .10) at birth and .3 kg less (P < .10) at 21 d of age but grew .026 kg/d faster (P < .10) from 70 d to slaughter, weighed 3.9 kg more at 165 d of age (P < .05), and reached 100 kg 7.0 d sooner (P < .05) than pigs out of control-line sows. Carcasses from barrows sired by select-line boars had .29 cm more (P < .10) fat at the 10th-rib than carcasses from barrows sired by control-line boars. Marbling scores were .31 unit greater (P < .05) and muscle color scores were .25 unit greater (P < .10) for carcasses from pigs out of select-line sows than for carcasses from pigs out of control-line sows. Selection for increased 70-d weight decreased age at 100 kg without increasing fat deposition. However, survival rates up to 100 kg were reduced. Mass selection for 200-d weight effectively increased 70-d weight, but fat thickness at 100 kg also increased. This content is only available as a PDF. Author notes 2 Present address: Dept. of Anim. Sci., Univ. of Georgia, Athens 30602. 3 Dept. of Anim. and Dairy Sci. Copyright © 1991 by American Society of Animal Science