Biomedical subjects

L L Southern

Publications and source records attributed to L L Southern.

At least 55 records · Page 3Linked to original sources

PubMed2001

Dietary effects of soy isoflavones on growth and carcass traits of commercial broilers.

Three experiments (EXP) were conducted to determine the effect of soy isoflavones (ISF) on growth and carcass traits of commercial broilers. The EXP were conducted simultaneously and a common control was used. In each EXP, treatments were replicated five times with five chicks each. Average initial and final BW were 102 and 2,890 g, 102 and 2,657 g, and 102 and 2,803 g for EXP 1,2, and 3, respectively, and the EXP were conducted from 9 to 52 d posthatching. In EXP 1, the effects of graded levels of supplemental ISF above those typically found in a corn-soybean meal (C-SBM) diet were studied. The treatments were 1) C-SBM, 2) C-SBM + ISF levels two times those in C-SBM (2x), and 3) C-SBM + ISF levels five times those in C-SBM (5x). The 2x and 5x levels of ISF decreased gain:feed (linear, P < 0.04) but increased (P < 0.04) breast weight compared with the C-SBM diet. Other performance and carcass traits were not affected (P > 0.05) by treatment. In EXP 2, the effects of low ISF levels in a C-soy protein concentrate (C-SPC) diet were studied. The treatments were 1) C-SBM, 2) C-SPC (low ISF), and 3) C-SPC + ISF (ISF levels equal to those in C-SBM). Average daily gain (ADG) and average daily feed intake (ADFI) were decreased (16 and 9%, respectively; P < 0.01) in chicks fed the C-SPC diets, regardless of ISF level. Gain:feed of chicks fed the C-SPC + ISF diet was decreased 9% (P < 0.02) compared with chicks fed the C-SBM diet, and gain:feed of chicks fed C-SPC was intermediate between the two. Carcass traits were not affected (P > 0.05) by treatment. In EXP 3, the effects of low ISF levels in a low CP diet were studied. The treatments were 1) C-SBM, 2) low CP (17,14, and 12% in the starter, growing, and finishing diets, respectively) with supplemental crystalline amino acids (low CP-AA), and 3) low CP-AA + ISF (ISF levels equal to C-SBM). Daily gain and gain:feed were decreased from 7 to 9% (P < 0.01) in chicks fed the low CP-AA and low CP-AA + ISF diet relative to those fed the C-SBM diet. Abdominal fat pad percentage was increased (P < 0.01) in chicks fed the low CP-AA diets compared with those fed the C-SBM diet. Dietary ISF can affect ADG and ADFI and may affect carcass traits in some instances.

Animal Feed↗

PubMed2001

Effects of betaine on growth, carcass characteristics, pork quality, and plasma metabolites of finishing pigs.

An experiment was conducted to determine the effect of dietary betaine (0, 0.125, 0.250, or 0.500%) on growth, carcass traits, pork quality, plasma metabolites, and tissue betaine concentrations of cross-bred finishing pigs. Four replications of three pigs (two barrows and one gilt) each were used for each treatment. The basal diet contained 0.85 (69 to 88 kg BW) or 0.65% Lys (88 to 115 kg BW). Overall ADG and gain:feed were not affected (P > 0.10) by betaine, but overall ADFI was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.01) by betaine; pigs fed 0.250% betaine had the lowest ADFI. Loin muscle area, average back-fat, dressing percentage, percentage lean, total fat, lean:fat, and leaf fat weight were not affected (P > 0.10) by betaine. Tenth-rib backfat thickness was decreased (quadratic, P < 0.05; 0 vs betaine, P < 0.05); pigs fed 0.250% betaine had the lowest 10th-rib backfat thickness. Carcass length was increased (linear, P < 0.05; 0 vs betaine, P < 0.10) as the level of betaine was increased. Fat-free lean, lean gain per day, ham weight, ham fat-free lean, and ham percentage lean were increased (quadratic, P < 0.10), but percentage fat, total ham fat, percentage ham fat, and butt-fat thickness were decreased (quadratic, P < 0.10); these traits were respectively highest or lowest in pigs fed 0.250% betaine. Thaw loss and 24-h pH were increased (quadratic, P < 0.10; 0 vs betaine, P < 0.05) and cook loss was decreased (linear, P < 0.05) in pigs fed betaine. The CIE L* value for the biceps femoris was decreased (quadratic, P < 0.10; 0 vs betaine, P < 0.10); pigs fed 0.250% betaine had the lowest CIE L* value. Subjective color, firmness-wetness, marbling, percentage moisture and bound water of the loin muscle, and shear force were not affected (P > 0.10) by betaine. Betaine was not detectable (< 0.07 mg/g) in the loin muscle of pigs fed 0% betaine, but betaine was detectable and relatively constant in pigs fed 0.125, 0.250, or 0.500% betaine (0.22, 0.17, and 0.21 mg/g, respectively). Plasma urea N, total protein, albumin, triglycerides, and HDL cholesterol concentrations were not affected (P > 0.10). Plasma total cholesterol (linear, P < 0.10) and NEFA (quadratic, P < 0.10) were increased in pigs fed betaine. Betaine improved carcass traits when provided at 0.250% of the diet and improved some aspects of pork quality.

Animal Feed↗

PubMed2001

Effects of betaine, pen space, and slaughter handling method on growth performance, carcass traits, and pork quality of finishing barrows.

An experiment was conducted to determine the effects of betaine, pen space, and preslaughter handling method on growth, carcass traits, and pork quality of finishing barrows. For the growth trial, a 2 x 2 factorial arrangement of treatments was used: betaine (0 or 0.250%) and(or) pen space (m2/pig; adequate, 0.035 BW0.67 kg, or inadequate, 0.025 BW0.67 kg). Each treatment was replicated five times with four barrows per replicate. At trial termination, two barrows from each pen were selected to receive either minimal or normal preslaughter handling. Reducing pen space decreased (P < 0.05) overall ADG and gain:feed and tended (P = 0.12) to decrease overall ADFI. Betaine had no affect (P > 0.10) on overall ADG, ADFI, or gain:feed. Pigs fed betaine had decreased (P < 0.10) carcass length. Other carcass and ham measurements were not affected (P > 0.10) by betaine. Pigs with inadequate pen space had increased (P < 0.10) ultimate pH, subjective color, cooking loss (fresh and frozen chop), and shear force but decreased rectal temperature, loin muscle CIE L*, biceps femoris CIE b*, and drip loss. Pigs subjected to minimal preslaughter handling had decreased (P < 0.10) rectal temperature, plasma cortisol, loin muscle CIE b*, and fresh chop total loss (drip + cooking loss). Pigs fed betaine had increased (P < 0.01) initial pH and decreased (P < 0.10) drip loss (fresh chop). Cooking loss and total loss (frozen chop) were decreased in pigs fed betaine with adequate pen space but increased in pigs fed betaine with inadequate pen space (betaine x pen space, P < 0.01). Pigs fed betaine may have improved pork quality.

Animal Husbandry↗

PubMed2001

Effects of dietary soy isoflavones on growth, carcass traits, and meat quality in growing-finishing pigs.

Two experiments were conducted to determine the effect of soy isoflavones on growth, meat quality, and carcass traits of growing-finishing pigs. In Exp. 1, 36 barrows (initial and final BW, 26 and 113 kg, respectively) were used and each treatment was replicated four times with three pigs each. The dietary treatments were 1) corn-soybean meal (C-SBM), 2) corn-soy protein concentrate (low isoflavones, C-SPC), or 3) C-SPC + isoflavones (isoflavone levels equal to those in C-SBM). Daily gain and ADFI were increased (P < 0.10) in pigs fed the C-SPC relative to pigs fed the C-SPC + isoflavone diet in the late finishing period; otherwise, growth performance was not affected (P > 0.10) by diet. Longissimus muscle area, 10th-rib fat depth, percentage muscling (National Pork Producers Council), 24-h pH and temperature, color, firmness-wetness, marbling, drip loss, and CIE L*, a*, and b* color values were not affected (P > 0.10) by diet. Dressing percentage, carcass length, weight and percentage of fat-free lean in ham and carcass, lean gain per day, lean:fat, and ham weight were increased (P < 0.10), and ham fat and percentage fat in ham and carcass were decreased (P < 0.10) in pigs fed the C-SPC + isoflavone diet compared with pigs fed the C-SPC diet. Pigs fed the C-SPC + isoflavone diet had similar (P > 0.10) carcass traits as pigs fed the C-SBM diet, except carcass length, percentage ham lean and thaw loss were greater (P < 0.10), and total ham fat was less (P < 0.10) in pigs fed the C-SPC + isoflavone diet. In Exp. 2, 60 gilts (initial and final BW, 31 and 116 kg, respectively) were used, and each treatment was replicated five times with four pigs per replicate. The treatments were 1) C-SBM, 2) C-SBM + isoflavone levels two times those in C-SBM, and 3) C-SBM + isoflavone levels five times those in C-SBM. Daily feed intake was linearly decreased (P < 0.10) in the growing phase and increased (P < 0.10) in the late finishing phases as isoflavone levels increased; otherwise, growth performance was not affected (P > 0.10) by diet. Diet did not affect (P > 0.10) carcass traits; however, CIE a* and b* color scores and drip loss were decreased (P < 0.06) as isoflavone levels increased. Soy isoflavones decreased fat and increased lean in barrows when fed within the dietary concentrations found in typical C-SBM diets but not when fed to gilts at concentrations above those present in C-SBM diets.

Animals↗

PubMed2001

Estimation of the total sulfur amino acid requirement and the effect of betaine in diets deficient in total sulfur amino acids for the weanling pig.

Four experiments were conducted to determine whether betaine (BET) could replace dietary methionine (MET) in diets for weanling pigs. Pigs in each experiment were allotted to treatments on the basis of weight in a randomized complete block design. Each treatment was replicated four (Exp. 4), five (Exp. 1 and 2), or six (Exp. 3) times with five or six pigs per replicate. In Exp. 1, pigs were fed a diet formulated to be deficient in total sulfur amino acids (TSAA) (negative control; NC) or the NC + 0.05 or 0.10% MET or BET during Phase 1 and 0.035 or 0.07% MET or BET during Phase 2. Growth performance was not affected (P > 0.10) by dietary treatments, indicating that the diets were not deficient in TSAA. In Exp. 2, graded levels of TSAA (0.74, 0.79, 0.84, 0.89, or 0.94%) were fed. Overall ADG was increased (0 vs added MET, P < 0.07) in pigs fed TSAA levels of 0.79% or greater, but gain:feed was not affected (P > 0.10) by diet. Overall ADFI was increased (linear, P < 0.08) and plasma urea N (PUN) was decreased (quadratic, P < 0.01) as the level of TSAA was increased. Most of the change in ADG, PUN, and ADFI occurred between 0.74 and 0.84% TSAA. Thus, the 0.74% TSAA diet was used in Exp. 3 as the NC. In Exp. 3, the diets included the following: 1) NC, 2) NC + 0.05% MET, 3) NC + 0.10% MET, 4) NC + 0.039% BET, or 5) NC + 0.078% BET. The addition of MET resulted in increased (linear, P < 0.10) ADG, ADFI, and gain:feed, but MET decreased PUN (linear, P < 0.05). Daily gain, ADFI, and TSAA intake were not different (P > 0.10) between pigs fed 0.05% MET or 0.039% BET, but gain:feed was decreased (P < 0.01) in pigs fed 0.039% BET compared with pigs fed 0.05% MET. In Exp. 4, a 2 x 2 x 2 factorial arrangement of treatments was used (MET, 0 or 0.072%; cystine, 0 or 0.059%; or BET, 0 or 0.057%). Overall ADG and gain:feed were increased (P < 0.10) in pigs fed MET. The intake of TSAA was increased (P < 0.05), and PUN was decreased (P < 0.10) in pigs fed MET or cystine. Overall ADFI was increased in pigs fed BET or MET independently but not affected when BET and MET were fed together (BET x MET, P < 0.10). The addition of BET to TSAA-deficient diets resulted in increased ADG, which was due to an increase in ADFI (TSAA intake). Thus, BET did not spare MET in this experiment.

Amino Acids, Sulfur↗

PubMed2001

Effect of chromium picolinate and chromium propionate on glucose and insulin kinetics of growing barrows and on growth and carcass traits of growing-finishing barrows.

Two experiments were conducted to determine the effects of dietary Cr tripicolinate (CrPic) or Cr propionate (CrProp) on growth, carcass traits, plasma metabolites, glucose tolerance, and insulin sensitivity in pigs. In Exp. 1, 36 barrows (12 per treatment; initial and final BW were 20 and 38 kg) were allotted to the following treatments: 1) corn-soybean meal basal diet (control), 2) as 1 + 200 ppb Cr as CrPic, or 3) as 1 + 200 ppb Cr as CrProp. Growth performance data were collected for 28 d, and then 23 pigs (seven, eight, and eight pigs for treatments 1, 2, and 3, respectively) were fitted with jugular catheters and a glucose tolerance test (500 mg glucose/kg BW) and an insulin challenge test (0.1 IU of porcine insulin/kg BW) were conducted. Both CrPic and CrProp decreased (P < 0.05) ADG and ADFI but did not affect gain:feed (P > 0.10). Fasting plasma glucose, total cholesterol, urea N, insulin, and high-density lipoprotein cholesterol:total cholesterol concentrations were not affected (P > 0.10) by either Cr source. Pigs fed CrPic had lower (P < 0.02) fasting plasma NEFA concentrations than control pigs, but plasma NEFA concentrations of pigs fed CrProp were not affected (P > 0.10). During the glucose tolerance test, glucose and insulin kinetics were not affected by treatment (P > 0.10). During the insulin challenge test, glucose clearance was increased (P < 0.01) in pigs fed CrProp but not affected (P > 0.10) in pigs fed CrPic. Glucose half-life was decreased (P < 0.03) in pigs fed CrPic or CrProp, but insulin kinetics were not affected (P > 0.10). In Exp. 2, 48 barrows (four replicates of four pigs per replicate; initial and final BW were 23 and 115 kg) were allotted to the same dietary treatments in a growing-finishing study. Average daily gain, ADFI, and gain:feed were not affected (P > 0.10) by treatments. Carcass length tended (P = 0.10) to be greater in pigs fed CrPic than in pigs fed CrProp, but other carcass measurements were not affected (P > 0.10). Glucose kinetics from the insulin challenge test indicate that both CrPic and CrProp increase insulin sensitivity and that both Cr sources are bioavailable.

Animals↗

PubMed2001

Effect of different protein sources on growth and carcass traits in growing-finishing pigs.

Crossbred gilts (n = 180) and barrows (n = 180) from the Louisiana State University (LSU) Agricultural Center and the University of Illinois (UI) were used to compare the effect of soybean meal in swine diets, relative to other protein sources, on growth performance and carcass traits of growing-finishing pigs. Four replications with five pigs each at each location were allotted to nine dietary treatments: soybean meal control (SBM), crystalline AA (corn-AA), extruded soybeans (ESB), canola meal (CAN), peanut meal (PNT), sunflower meal (SFLR), ground peas, meat and bone meal (MBM), and poultry by-product meal (PLTY). The diets were formulated to meet or exceed NRC nutrient requirements and to have equal Lys:ME according to dietary phase and sex. Corn was the grain source in all diets and the protein sources were the sole source of supplemental protein in all diets except when AA were added to meet the requirement. Pigs (three per pen at each location) were killed at an average final BW of 114 kg in the LSU or UI Meat Science Laboratories. Pigs fed SBM had greater (P < 0.05) ADG than pigs fed the corn-AA, CAN, SFLR, MBM, or PLTY and greater (P < 0.05) ADFI relative to pigs fed the corn-AA, ESB, MBM, or PLTY. Gain:feed was decreased (P < 0.05) in pigs fed corn-AA or SFLR but increased (P < 0.05) in pigs fed ESB compared with pigs fed the SBM diet. Loin muscle area was decreased (P < 0.05) in pigs fed the corn-AA or MBM diets compared with pigs fed the SBM diet. Tenth-rib backfat thickness was greater (P < 0.10) in pigs fed corn-AA, peas, or MBM than in those fed SBM. The NPPC percentage acceptable quality lean and kilograms of lean were decreased (P < 0.10) in pigs fed corn-AA, peas, or MBM compared with those fed SBM. Results from this experiment suggest that pigs fed SBM have equal or better growth performance and carcass traits than pigs fed other protein sources.

Animal Feed↗

PubMed2000

The effect of dietary betaine in Eimeria acervulina-infected chicks.

Two experiments were conducted to evaluate the effect of dietary betaine in broiler chicks with either chronic (CHR; 2.5 x 10(5) sporulated oocysts on Day 1, 4, 7, and 10) or acute (ACT; 1.0 x 10(6) sporulated oocysts on Day 1) Eimeria acervulina infections. Three hundred (Experiment 1) or 600 (Experiment 2), 4-d-old male chicks were used in the 14-d experiments. In both experiments, a 2 x 3 factorial arrangement of treatments was used: two levels of betaine (0 or 0.075%) and three levels of coccidiosis infection (uninfected, CHR, or ACT). Each treatment was replicated five (Experiment 1) or 10 (Experiment 2) times with 10 chicks per replicate. In Experiment 1, the ACT infection decreased (P < 0.01) average daily gain and gain:feed, and the CHR infection decreased (P < 0.02) average daily gain. The ACT and CHR infections decreased (P < 0.06) Day 7 plasma carotenoids and Day 14 plasma total protein, and the ACT infection also decreased (P < 0.06) Day 7 plasma total protein. Average daily gain and Day 7 plasma total protein were increased in CHR chicks fed betaine but were decreased in uninfected chicks fed betaine (CHR x betaine; P < 0.09). Chicks fed betaine had decreased (P < 0.06) Day 7 plasma carotenoids. In Experiment 2 the CHR and ACT infections decreased (P < 0.01) average daily gain, average daily feed intake, grain:feed ratio, Days 7 and 14 plasma carotenoids, and Day 7 plasma total protein. Chicks fed betaine had increased (P < 0.07) average daily gains, gain:feed ratios, and lesion scores. Day 14 plasma carotenoids and plasma total protein were decreased in uninfected chicks fed betaine but were increased in CHR chicks fed betaine (CHR x betaine; P < 0.04); plasma carotenoids also were increased in ACT chicks fed betaine (ACT x betaine; P < 0.05). Betaine did not consistently affect growth performance, plasma constituents, or lesion score in CHR or ACT coccidiosis-infected chicks.

Animal Nutritional Physiological Phenomena↗

PubMed2000

The effect of varying mix uniformity (simulated) of phytase on growth performance, mineral retention, and bone mineralization in chicks.

An 18-d experiment was conducted to determine the effect of varying mix uniformity of phytase on growth performance, mineral retention, and bone mineralization in chicks. Chicks (initial and final weights were 74.5 and 803.3 g) were allotted to seven treatments with six (Treatment 1) or seven (Treatments 2 to 7) replicates of seven chicks per replicate in a completely randomized design. Varying mix uniformity of phytase was simulated by alternately providing two diets with two different concentrations of microbial phytase; the diets were switched every 24 h. Treatments were: 1) positive control (CON) (Ca, 1.0%; available phosphorus (aP), 0.45%), 2) negative control (NEG) (Ca, 0.9%; aP, 0.35%), 3) NEG + 600 phytase units (FTU) daily (CV0), 4) NEG + 500 or 700 FTU (CV17), 5) NEG + 400 or 800 FTU (CV34), 6) NEG + 200 or 1,000 FTU (CV69), or 7) NEG + 0 or 1,200 FTU (CV103). Gain, feed intake, and bone breaking strength were similar (P > 0.15) in the CON and CV0 treatments, but these response variables were decreased in the NEG treatment (P < 0.01). Gain:feed was not affected by treatment (P = 0.15). Bone ash was decreased (P < 0.02) by the NEG and CV0 treatments compared with the CON diet, but chicks fed the CV0 diet had greater bone ash than those fed the NEG (P < 0.01) diet. Increasing FTU CV decreased bone breaking strength and bone ash (P < 0.01). Calcium and phosphorus retention (P < 0.08) and gain (P < 0.09) were numerically decreased, and phosphorus excretion was numerically increased (P < 0.07) as FTU CV increased. The difference between the CV0 and CV103 treatments was significant only for bone breaking strength and ash (P < 0.01). In conclusion, increasing phytase CV had little effect on growth performance, whereas bone ash and breaking strength and calcium and phosphorus retention and excretion decreased only at the most extreme CV.

6-Phytase↗

PubMed2000

Effect of feather meal as a source of valine for lactating sows.

An experiment was conducted to evaluate feather meal as a source of Val in lactating sow diets. Sows (five farrowing groups; mean parity = 2.34) were allotted to one of two dietary treatments on the basis of ancestry, parity, and weight and date of d 110 of gestation. The treatment diets included 1) corn-soybean meal lactation diet (n = 40) or 2) corn-soybean meal lactation diet with 2.5% feather meal (n = 39). The diets were formulated on an equal Lys basis. All litters were adjusted to 10 pigs within 24 h after farrowing, and all sows weaned at least nine pigs. Sows were bled at 110 d of gestation and at weaning, and serum urea N was determined. Backfat thickness was determined ultrasonically at 110 d of gestation and at weaning. Serum urea N and backfat thickness at d 110 of gestation were used as covariates for serum urea N and backfat thickness at weaning, respectively. The litter response criteria (weaning weight, litter weight gain, and percentage survival) were not affected (P > .10) by feather meal. The sow response criteria (weaning weight, weight loss per day, weaning backfat thickness, change in backfat thickness, ADFI, and days to estrus) were not affected (P > .10) by feather meal. Sows fed feather meal had increased (P < .01) serum urea N and tended (P = .15) to have decreased sow weaning weight. Following the initial analysis of the data, the data set was split into two groups: 1) sows with litters gaining less than 2.17 kg/d (n = 19 and 20 for control and feather meal diets, respectively) and 2) sows with litters gaining more than 2.17 kg/d (n = 21 and 19 for control and feather meal diets, respectively). These two groups were analyzed separately. In sows with litters gaining less than 2.17 kg/d, the litter and sow criteria were not affected (P > .10) by treatment. In sows with litters gaining more than 2.17 kg/d, sow weaning weight was decreased (P < .04) and sow weight loss (P < .02) and serum urea N (P < .01) were increased in sows fed feather meal. Feather meal (as a source of Val) did not improve litter weight gain, but it increased serum urea N.

Animal Feed↗

PubMed2000

Growth promotion effects and plasma changes from feeding high dietary concentrations of zinc and copper to weanling pigs (regional study).

An experiment was conducted to determine the effect of high dietary intakes of Zn and Cu and their combination on growth performance of weanling pigs with diverse health status and management strategies. Twelve experiment stations cooperated and used a total of 1,356 pigs that averaged 6.55 kg BW and 22.2 d age at weaning. The four dietary treatments, all of which met or exceeded NRC requirements, were 1) control, 2) 3,000 ppm Zn (from Zn oxide), 3) 250 Cu ppm (from Cu sulfate), or 4) 3,000 ppm Zn and 250 ppm Cu. The diets were fed as a complex Phase I diet (1.4% lysine) for 7 d followed by a Phase II diet (1.2% lysine) for 21 d. Chlortetracycline (220 ppm) was added to all diets. Fecal color (1 = yellow to 5 = black) and consistency (1 = very firm to 5 = very watery) were scored daily for 3 wk. At the end of the 28-d study, 412 pigs were bled at five stations, and plasma Cu, Zn, and Fe concentrations were determined at one station with atomic absorption spectrophotometry. Average daily gain (375, 422, 409, 415 g/d), feed intake (637, 690, 671, 681 g/d), and gain/feed (586, 611, 611, 612 g/kg) were improved (P < .01) by the addition of Zn and(or) Cu. Significant Cu x Zn interactions imply that the responses to Zn and Cu were independent and not additive. There were significant (P < .01) Zn and Cu effects and a Zn x Cu interaction on fecal color (3.17, 3.24, 4.32, 3.57) and consistency (2.39, 2.14, 2.14, 2.13). Dietary additions of Cu and Zn resulted in elevated plasma concentrations of Cu and Zn, respectively. These data indicate that pharmacological additions of 3,000 ppm Zn (oxide) or 250 ppm Cu (sulfate) stimulate growth beyond that derived from intakes of Zn and Cu that meet nutrient requirements. However, the combination of Zn and Cu did not result in an additive growth response.

Animal Feed↗

PubMed2000

Ornithine alpha-ketoglutarate and creatine effects on growth and plasma metabolites of nursery pigs.

Four experiments were conducted to determine the effect of dietary ornithine alpha-ketoglutarate (OKG) and creatine monohydrate on growth performance and plasma metabolites of nursery pigs. In each experiment, treatments were replicated with four to five pens of four to six pigs each. Each experiment lasted from 3 to 4 wk and Phase I (1.6% Lys) and Phase II (1.3 to 1.5% Lys) diets were fed for 9 to 16 d each. In Exp. 1, pigs (4.7 kg and 15 d of age) were fed diets containing 0, .10, or .75% OKG. Daily gain during a 13-d Phase I period and ADFI during Phase I and overall (29 d) were increased (P < .10) in pigs fed .75% OKG. Gain:feed ratio was not affected (P > .10) by diet. In Exp. 2, pigs (7.1 kg and 23 d of age) were fed 0 or .50% OKG during Phase I only. During Phase I, II, and overall, ADG and ADFI were not affected (P > .10) by OKG supplementation, but gain:feed was decreased during Phase I (P < .04), Phase II (P < .08), and overall (P < .04). Plasma urea N (PUN), glucose, and NEFA concentrations were not affected (P > .10) by OKG supplementation in this experiment. In Exp. 3, pigs (5.8 kg and 20 d of age) were fed diets containing 0, .10, or .50% creatine. Creatine tended to linearly decrease ADG (P = .11) and plasma albumin (P = .12) and PUN (P < .10) concentrations in Phase II (d 12 to 26). In Exp. 4, 850 mg of OKG or 750 mg of creatine was provided daily by oral capsule to pigs 4 d before weaning to 2 d after weaning. Pigs within a litter received either no capsule or capsules containing OKG or creatine. After weaning, pigs that received no capsule before weaning received no treatment, .50% creatine, or .50% OKG in the nursery diet. Pigs that received OKG before weaning received no treatment or .50% OKG, and pigs that received creatine before weaning received no treatment or .50% creatine in the nursery diet. Pigs weighed 3.9 kg 4 d before weaning and 4.9 kg at weaning at an average age of 20 d. The OKG provided by capsule decreased ADG (P < .02) and ADFI (P < .09) during Phase II. The OKG did not affect (P > .10) plasma NEFA, glucose, or urea N concentrations. Creatine added to the nursery diet increased (P < .02) ADFI and decreased (P < .10) gain:feed during Phase II and overall. Creatine in the nursery diet also increased (P < .01) PUN, but it did not affect plasma glucose or NEFA concentrations. Creatine and OKG have variable effects on growth performance and plasma metabolites of nursery pigs.

Animal Feed↗

PubMed2000

Further assessment of the dietary lysine requirement of finishing gilts.

A cooperative research study involving 635 gilts was conducted at eight research stations to further estimate the lysine requirement of finishing gilts. Dietary crude protein levels of the five dietary treatments ranged from 16.0 to 24.4% with calculated lysine levels of .80, .95, 1.10, 1.25, or 1.40%. Each station contributed a minimum of two replicate pens of pigs per treatment. Average initial and final weights were 53.6 and 116.4 kg, respectively. At the end of the experimental period, pigs were killed and hot carcass weight, 10th-rib fat depth, and longissimus muscle area were measured. Carcass fat-free lean percentage and fat-free lean gain were estimated from these data. Daily lysine intakes averaged 21.8, 25.9, 30.5, 34.3, and 37.8 g/d for the five treatment groups, respectively. Increasing the dietary lysine from .80 to .95% numerically increased weight gain and gain:feed, but these increases were not maintained at higher levels of dietary lysine. Overall, rate and efficiency of gain decreased (cubic, P < .01) with increasing dietary lysine. Carcasses were leaner at the two higher levels of dietary lysine as evidenced by reduced 10th rib backfat (linear, P < .01), increased longissimus area (quadratic, P < .04), and increased percentage of estimated fat-free lean (linear, P < .01). Carcass fat-free lean gain was not influenced by dietary lysine except for a small numerical improvement (P < .11) at the .95% level of dietary lysine that paralleled the improvement in body weight gain. The results indicate that the dietary lysine requirement of finishing gilts with a mean carcass fat-free lean growth rate of 306 g/d from 54 to 116 kg body weight is probably no higher than .80% of the diet to achieve maximum rate and efficiency of body weight gain and carcass lean growth rate. The results also indicate that higher dietary lysine levels may increase carcass leanness in finishing gilts, possibly due to reduced intake of NE. Whether this response is due to the effects of lysine alone, protein (i.e., other amino acids), or soybean meal is unknown.

Animal Nutritional Physiological Phenomena↗

PubMed1999

Dietary protein and chromium tripicolinate in Suffolk wether lambs: effects on production characteristics, metabolic and hormonal responses, and immune status.

Thirty-two Suffolk wether lambs were fed for 84 d in a 2 x 2 factorial experiment using two levels of dietary protein (9.0 to 12.1% CP, low protein, LP; or 12.8 to 14.4% CP, high protein, HP) and supplemental Cr (none, C; or 400 ppb Cr as chromium tripicolinate, Cr). At 14- to 21-d intervals, lambs were weighed, and jugular blood samples were collected. Mean ADG and carcass weight (P > .10) did not differ. In lambs fed HP, Cr reduced liver weight and increased kidney weight (P < .01). Lambs fed HP had elevated plasma urea N (PUN; P < .01) and albumin (P < .04). During an i.v. epinephrine challenge on d 43, plasma cortisol declined in lambs fed Cr (Cr x time, P < .03) and in lambs fed LP (CP x time, P < .001). An i.v. glucose tolerance test conducted 3 h later showed that supplemental Cr decreased glucose clearance rate in lambs fed HP (CP x Cr, P < .10) but not in lambs fed LP. On d 62, PUN was increased in lambs fed HP (P < .001) between 0 and 3 h postprandial, and there was a Cr x CP interaction (P < .04). Postprandial plasma NEFA declined with Cr vs C (Cr x time, P < .07) and with HP vs LP (CP x time, P < .10). By d 66, lambs fed Cr had an elevated (P < .03) blood platelet and fibrinogen content. Chromium increased erythrocyte count in lambs fed HP (Cr x CP, P < .08), and isolated peripheral lymphocytes had greater blastogenic response to 4 microg/mL of phytohemagglutinin (Cr x CP, P < .001). The lymphocyte response to pokeweed mitogen (.2 microg/mL) was reduced in lambs fed Cr (P < .10). In the present experiment, Cr supplementation had minimal and inconsistent effects on production and metabolic criteria of lambs.

Animals↗

PubMed1998

The lysine requirement and ratio of total sulfur amino acids to lysine for chicks fed adequate or inadequate lysine.

Experiments (Exp.) were conducted with Cornish Rock males (4 to 14 or 15 d of age) to determine the Lys requirement (Exp. 1) and the optimum ratio of TSAA:Lys for chicks fed adequate or inadequate Lys (Exp. 2). In Exp. 1, 180 chicks were allotted on the basis of BW to six treatments with six replications of five chicks each in a completely randomized design (CRD). Average initial and final BW were 73.5 and 415.5 g. The Lys levels fed were: 0.8, 0.9, 1.0, 1.1, 1.2, and 1.3% digestible Lys. In Exp. 2, 240 chicks were allotted on the basis of BW to 12 treatments with four replications of five chicks each in a CRD. Average initial and final BW were 68.5 and 336.3 g. Chicks were fed either 0.82 or 1.0% digestible Lys and within each Lys level, a ratio of TSAA:Lys of: 0.55, 0.63, 0.72, 0.80, 0.88, and 0.96, resulting in a 2 x 6 factorial arrangement of treatments. At the end of each trial, all chicks were weighed and pen feed consumption was measured. In Exp. 1, average daily gain (ADG) and gain:feed (GF) increased (linear, P < 0.01; quadratic, P < 0.02) as dietary Lys increased. A cubic (P < 0.04) effect of Lys for average daily feed intake (ADFI) was observed. One-slope, broken-line regression models estimated Lys requirements of 1.0, 0.9, and 1.1% for ADG, ADFI, and GF, respectively. In Exp. 2, chicks fed 1.0% Lys had higher (P < 0.01) ADG, ADFI, and GF than chicks fed 0.82% Lys. Daily gain, ADFI, and GF increased (linear, P < 0.01; quadratic, P < 0.01) as TSAA:Lys increased. For ADG, ADFI, and GF, one-slope, broken-line regression models estimated required ratios of TSAA:Lys of 0.66, 0.71, and 0.63 for chicks fed 1.0% Lys and 0.66, 0.67, and 0.63 for chicks fed 0.82% Lys. There were no differences (P > 0.05) in the estimated ratios of TSAA:Lys required to maximize ADG, ADFI, and GF for chicks fed 0.82 and 1.0% Lys. Thus, similar ratios of an indispensable amino acid to Lys can be obtained when chicks are fed at or slightly below their Lys requirement.

Amino Acids, Sulfur↗

PubMed1998

Interactive effects of sodium bentonite and coccidiosis with monensin or salinomycin in chicks.

Three experiments (Exp.) were conducted to determine the interactive effects of sodium bentonite (NaB) with the efficacy of monensin (MON) or salinomycin (SAL) in coccidiosis-infected chicks. Male broiler chicks 5 to 14 d of age were used, and each treatment was replicated with eight (Exp. 1) or four (Exp. 2 and 3) pens of five chicks each. In Exp. 1, MON (80 ppm), NaB (0.50%), or MON+NaB were fed to uninfected and coccidiosis-infected (5 x 10(5) sporulated Eimeria acervulina oocysts on Day 2 of the Exp.) chicks in a 2 x 2 x 2 factorial arrangement of treatments. Experiment 2 was identical to Exp. 1, but SAL (30 ppm) replaced MON as the anticoccidial additive. In Exp. 3, MON (55 ppm) or SAL (22 ppm) were added individually or with NaB (0.50%) to diets for uninfected or coccidiosis-infected chicks. Coccidial infection reduced (P < 0.01) gain, feed intake, gain:feed, plasma carotenoids, and percentage tibia ash in all experiments. The MON and SAL additions increased these response criteria in infected chicks (coccidiosis by anticoccidial, P < 0.07), except MON did not increase (P > 0.10) feed intake or tibia ash in Exp. 3. In Exp. 3, NaB partially reduced the positive effect of MON on daily gain (NaB by MON, P < 0.03), and of SAL on feed intake (NaB by SAL, P < 0.08). The NaB addition also increased gain:feed (P < 0.08), and the increase was greater in infected chicks (coccidiosis by NaB, P < 0.08). Also in Exp. 3, SAL increased feed intake more in chicks not fed NaB than in chicks fed NaB (SAL by NaB, P < 0.08). Dietary NaB (0.5%) may reduce the efficacy of MON and SAL in coccidiosis-infected chicks when these additives are added at less than recommended levels.

Animals↗

PubMed1998

Effect of dietary fiber or fat in low-crude protein, crystalline amino acid-supplemented diets for finishing pigs.

Three experiments were conducted to determine the effect of reducing NE, by adding dietary fiber in Exp. 1 and 2 and decreasing dietary fat in Exp. 3, of low-CP, crystalline amino acid (CAA)-supplemented diets for finishing pigs on growth performance and carcass characteristics. In Exp. 1 and 2, 64 barrows (Exp. 1) or gilts (Exp. 2) were allotted to four treatments with four replicates of four pigs each. Average initial and final BW were 74 and 117 kg in Exp. 1 and 74 and 102 kg in Exp. 2. The following diets were fed in Exp. 1: 1) corn-soybean meal (C-SBM); 2) low-CP (-3.5%), supplemented with CAA; 3) CAA + rice hulls (CAA+RH; NE equal to Diet 1); and 4) CAA+RH+OIL (NE equal to Diet 2). Experiment 2 was similar to Exp. 1, except RH were replaced with wheat middlings (WM), oil was replaced with dry fat, and the CP was decreased by 3.1% in the low-CP diets. In both experiments, serum urea-N (SUN, corrected for initial SUN by covariance analysis) was higher (P<.10) for pigs fed C-SBM than for pigs fed any other diet. In Exp. 1, barrows fed CAA+RH had lower hot carcass weight, percentage muscle, fat-free lean (FFLEAN), lean gain per day, retained energy (RE) in FFLEAN, and lean:fat ratio than barrows fed C-SBM, along with less FFLEAN than barrows fed CAA+RH+OIL. Barrows fed CAA+RH had smaller longissimus muscle areas than barrows fed any other diet, and barrows fed C-SBM had higher dressing percentage and lower percentage total fat than barrows fed any other diet. Barrows fed C-SBM had higher lean:fat ratio and lower total fat than barrows fed CAA. In Exp. 2, gilts fed CAA+WM+FAT had heavier heart weights than gilts fed C-SBM or CAA (P<.10). In Exp. 3, 702 gilts were allotted to six treatments with nine replicates of 13 gilts each. Average initial and final BW were 70 and 110 kg. Gilts were fed two levels of CP (15.5 or 11.7% plus CAA added to meet an ideal amino acid ratio) and three levels of NE (2,650, 2,617, or 2,584 kcal/kg), resulting in a 2x3 factorial arrangement of treatments. Gilts fed 15.5% CP had higher gain:feed ratio than gilts fed 11.7% CP (P<.01). Longissimus depth was greater for gilts fed 15.5% CP than for gilts fed 11.7% CP and was decreased as NE decreased only in gilts fed 11.7% CP (CP effect, P<.09; NE linear effect, P<.04; CP x NE effect, P<.01). Gilts fed the diet with 2,617 kcal NE had lighter carcasses and less total fat, fat gain per day, RE, and RE as fat regardless of protein level than gilts fed 2,650 or 2,584 kcal NE/kg (NE quadratic, P<.09). Loin color score increased as NE decreased (linear, P<.06), but longissimus fat depth was increased by the lowest level of NE (NE quadratic effect, P<.09). Overall, the reduction of NE in low-CP, CAA-supplemented diets did not affect growth performance and was not an effective means of reducing fat in finishing pigs.

Amino Acids↗

PubMed1998

Ratio of total sulfur amino acids to lysine for finishing pigs.

We conducted two experiments to determine the optimum ratio of total sulfur amino acids (TSAA) to Lys for late finishing pigs. In Exp. 1, 50 barrows and 50 gilts were allotted to treatments with three replicates of three or four pigs per replicate in a randomized complete block (RCB) design within a split-plot arrangement of treatments. Sex was the whole plot and TSAA:Lys ratio was the subplot. Average initial and final BW were 77 and 111 kg. Barrows and gilts were fed diets formulated to contain .55 and .65% Lys, respectively. The ratios of TSAA:Lys were .50, .55, .60, .65, and .70. Diets met or exceeded an ideal amino acid pattern for all indispensable amino acids (except TSAA), and all diets were isonitrogenous and equal in electrolyte balance. In Exp. 2, 60 gilts were allotted to five treatments with four replicates of three gilts each in a RCB design. Average initial and final BW were 74 and 110 kg. Gilts were fed diets formulated to contain .65% Lys. The ratios of TSAA:Lys were .35, .425, .50, .575, and .65. In Exp. 1, there were no TSAA:Lys ratio effects (P > .10) for ADG, final BW, percentage muscle, longissimus muscle area, carcass length, percentage fat-free lean (PFFLEAN), lean gain per day (LGD), total fat (TOFAT), percentage TOFAT (PTOFAT), fat gain per day (FGD), lean:fat, retained energy in TOFAT as ether extractable lipid (RE-F), retained energy (RE), or serum urea N (SUN). Feed intake (ADFI) was greater (quadratic, P < .05) for pigs fed .70 TSAA:Lys than for pigs fed any other treatment. Hot carcass weight, psoas muscle weight, 10th rib fat thickness, dressing percentage, fat-free lean (FFLEAN), and retained energy in FFLEAN as protein (RE-P) responded inconsistently to TSAA:Lys ratio, resulting in cubic (P < .09) effects. In Exp. 2, ADFI (linear, P < .08), TOFAT (linear, P < .05), PTOFAT (linear, P < .07), FGD (linear, P < .05), RE-F (linear, P < .05), RE (linear, P < .05), and SUN (linear, P < .02; quadratic, P < .01) decreased as TSAA:Lys ratio increased. Also, gain:feed (GF) (linear, P < .01; quadratic, P < .04), PFFLEAN (linear, P < .04), and lean:fat (linear, P < .04) increased as TSAA:Lys ratio increased. One-slope, broken-line regression models estimated required ratios of TSAA:Lys of .44 (SUN), .40 (ADG), .47 (ADFI), .45 (GF), .45 (FFLEAN), .44 (LGD), .65 (TOFAT), .65 (FGD), .44 (RE-P), .65 (RE-F), .65 (RE), and .57 (lean:fat). Thus, for growth and muscling traits of late finishing pigs, the optimum ratio of TSAA:Lys is less than the current proposed ratio (.65), but to minimize fat accretion, the ratio is .65.

Amino Acids, Sulfur↗