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R D Goodband

Publications and source records attributed to R D Goodband.

At least 73 records · Page 4Linked to original sources

Growth and microbial flora of nonmedicated, segregated, early weaned pigs from a commercial swine operation.

OBJECTIVE: To determine whether segregated, early weaned pigs have better growth performance and different microbial flora than those pigs raised on-site. DESIGN: Prospective, observational study. ANIMALS: Pigs from a commercial operation that were known to be infected with several common swine pathogens. PROCEDURE: Pigs (7 to 10 days old) were weaned and segregated from the farm of origin and compared with littermate control pigs (14 to 17 days old) that were weaned and raised on-site. Pig weight was measured and microbial flora were isolated at 14-day intervals for 84 days, beginning when the pigs were 7 to 10 days old. RESULTS: At 50 days of age, the segregated, early weaned pigs had a mean weight of 23.7 kg, compared with a mean weight of 12.5 kg for control pigs. Pasteurella multocida was isolated from fewer segregated, early weaned pigs than from controls. Signs of Mycoplasma hyopneumoniae infection were detected in control pigs but not in segregated early weaned pigs. Clinical, serologic, or bacteriologic signs of early postnatal vertical transmission of Actinobacillus pleuropneumoniae were not detected in either group. CLINICAL IMPLICATION: Vertical transmission of M hyopneumoniae was prevented by weaning pigs at 7 to 10 days of age and segregating them off-site, without the use of medication. Although medicated controls were not compared, results from this herd revealed that use of antibiotics is not the most important factor for disease control in segregated, early weaning programs. Minimizing antibiotic use in disease-control protocols reduces costs as well as removes the need for extra-label drugs.

Actinobacillus pleuropneumoniae↗

Influence of weaning age and nursery diet complexity on growth performance and carcass characteristics and composition of high-health status pigs from weaning to 109 kilograms.

We examined the influence of weaning age (9 or 19 +/- 1 d) and nursery diet complexity on growth performance and carcass composition of 192 high-health status barrows from weaning to 109 kg. Pigs were fed diets of different complexity (high, medium, or low) in various regimens from weaning to 18.7 kg. They then were fed common corn-soybean meal-based diets from 18.7 to 109 kg. Increasing diet complexity improved ADG from weaning to 7.0 kg (P < .10) but had no effect (P > .10) from 7.0 to 18.7 kg. Thus, increasing diet complexity seems to improve ADG only in the early period after weaning. Age at 109 kg was similar (P > .10) for the pigs weaned at 9 and 19 d. However, pigs fed the medium-complexity regimens were the youngest (P < .01) at 109 kg. Interactions (P < .06) were observed for carcass lipid and lipid:protein accretion from 18.7 to 109 kg. These were the result of pigs weaned at 9 d of age having higher carcass lipid and lipid:CP accretion rates when fed the low-complexity regimens than when fed the medium- or high-complexity regimens. However, pigs weaned at 19 d of age had similar carcass lipid and lipid:protein accretion ratios regardless of diet complexity. When health status was similar, growth performance was similar between weaning ages but was influenced by diet complexity. Carcass lipid and lipid:protein deposition ratios increased when simple regimens were fed to pigs weaned at 9 d of age in the subsequent growing-finishing period.

Aging↗

The influence of genotype, sex, and dietary lysine on pork subprimal cut yields and carcass quality of pigs fed to either 104 or 127 kilograms.

One hundred twenty pigs (initially 44 kg BW) were used to determine the effects of genotype, sex, and dietary lysine on subprimal cut yields and carcass quality. Within genotype (high or medium potential for lean tissue gain), barrows and gilts were fed separately either a .90 or .70% lysine diet until the mean weight of each pen of three pigs reached 104 kg. Then one pig was removed and dietary lysine for the remaining two pigs was decreased to .75 or .55%, respectively. At both 104 and 127 kg BW, carcasses from high-lean genotype (HLG) pigs and gilts had (P < .01) higher percentages of boneless closely trimmed ham, loin, and shoulder than carcasses from medium-lean genotype (MLG) pigs and barrows, respectively. At 104 kg BW HunterLab values indicated (P < .01) that HLG longissimus muscle (LM) was redder, more yellow, and more intense in color than MLG LM. The LM from HLG gilts had (P < .05) higher Warner-Bratzler shear values (less tender) than LM from HLG barrows and MLG pigs at 104 kg BW. At 127 kg BW, HLG LM was visually firmer (P < .05) and more reddish-pink (P < .01); had HunterLab values (P < .01) that indicated a darker, redder color; had less moisture exudate (P < .05), thaw loss (P < .01), and percentage of lipid (P < .01); and had a higher pH (P < .05) than MLG LM. Barrow LM had more marbling (P < .05), a higher percentage of lipid (P < .01), less moisture exudate (P < .05), and less thaw loss (P < .01) than LM from gilts. The LM from HLG barrows had higher (P < .05) Warner-Bratzler shear values than the LM from HLG gilts and MLG pigs at 127 kg BW. Overall, the dietary regimens used in this trial resulted in minimal differences in either carcass quality or cutability. The production option of feeding HLG gilts to 127 kg can be used to optimize carcass cutability and quality traits.

Animals↗

Valine requirement of the high-producing lactating sow.

Two hundred three (40 or 41/treatment, average parity 4.3) Large White x Landrace or Large White x Chester White x Landrace sows were used to determine the valine requirement of sows with a genetic capacity for high milk production. All diets were formulated to contain .90% total lysine, with all amino acids other than valine formulated to be at least 110% of their suggested estimates relative to lysine based on ratios derived from the National and Agricultural Research Councils. The control diet was formulated to .75% total valine, and crystalline valine replaced cornstarch to provide additional treatments containing .85, .95, 1.05, and 1.15% total dietary valine. Corresponding valine:lysine ratios were 83, 94, 106, 117, and 128%. Mean litter size after adjustment was 10.3 pigs across treatments, and average lactation length was 26 d. Number of pigs weaned was not affected by dietary valine (mean = 10.2 pigs), nor was daily sow feed (mean = 6.24 kg) or lysine (mean = 56 g) intake. Valine intake increased (linear, P < .001) as dietary valine increased. Litter weight at d 21 and at weaning (d 26) increased (linear, P < .02) with increasing dietary valine (62.4 to 65.5 kg and 76.1 to 79.9 kg, respectively). Litter weight gain increased from d 0 to 7 (linear, P < .06) and from d 0 to 21 and d 0 to weaning (linear, P < .02) as dietary valine increased. Dietary valine had no effect (P > .10) on sow weight change, 10th rib, or last lumbar backfat change from d 0 to 21 or d 0 to weaning or on days from weaning to estrus. These results demonstrate that increasing dietary valine for high-producing sows (21-d litter weights > 60 kg) results in improved litter weight gain. Based on the linear responses observed, the requirement is at least 1.15% of the diet (72 g/d of valine intake) to maximize litter weaning weight and litter weight gain, much greater than recommended currently by the National Research Council (100% of lysine, 36.5 g/d) or the Agricultural Research Council (70% of lysine, 25.5 g/d).

Amino Acids↗

Effect of L-carnitine and soybean oil on growth performance and body composition of early-weaned pigs.

Two experiments were conducted to evaluate the effect of dietary L-carnitine on growth performance and body composition of early-weaned pigs. In Exp. 1, 120 weanling pigs (initially 5.6 kg and 19 +/- 2 d of age) were allotted in a 3 x 2 factorial with four pigs per pen and five replications (pens) per treatment. Main effects from d 0 to 14 after weaning included dietary L-carnitine (0, 500, or 1,000 ppm) and soybean oil (0 to 10%). From d 14 to 35 after weaning, levels were reduced to 0, 250, or 500 ppm L-carnitine and 0 or 5% soybean oil. No L-carnitine x soybean oil interactions were observed (P > .10). From d 0 to 14, L-carnitine and soybean oil had no effect (P > .10) on pig performance. From d 14 to 35 and d 0 to 35, gain:feed ratio (G/F) improved (linear, P < .05) with increasing dietary L-carnitine; however, ADG and ADFI were not affected. Soybean oil improved ADG and G/F (P < .05) from d 14 to 35 and ADG from d 0 to 35. In Exp. 2, 180 weanling pigs (initially 6.0 kg and 22 +/- 2 d of age) were allotted in a 2 x 3 factorial. Pigs were fed either 0 or 1,000 ppm L-carnitine from d 0 to 14 after weaning and then pigs fed each of these diets were fed diets containing 0, 250, or 500 ppm L-carnitine from d 14 to 35. No interactions occurred between feeding L-carnitine from d 0 to 14 and performance observed from d 14 to 35. From d 0 to 14 after weaning, L-carnitine increased ADG (P < .08) and ADFI (P < .02). From d 14 to 35, ADFI decreased (linear, P < .05) and G/F increased (quadratic, P < .05) as dietary L-carnitine increased. Cumulative (d 0 to 35) ADFI decreased (linear, P < .05) and G/F increased (linear, P < .05) with increasing L-carnitine. On d 35, 14 pigs from each of four selected treatments (0 or 1,000 ppm L-carnitine from d 0 to 14 followed by either 0 or 500 ppm from d 14 to 35) were slaughtered, and carcass composition was recorded. Carcass moisture and CP percentages were not influenced (P > .10) by dietary L-carnitine. However, pigs fed 1,000 ppm L-carnitine from d 0 to 14 had less (P < .05) carcass lipid and daily lipid accretion on d 35 whether they were fed L-carnitine from d 14 to 35 or not. These results suggest that dietary L-carnitine improves G/F and reduces carcass lipid accretion in early-weaned pigs.

Aging↗

Influence of lipopolysaccharide-induced immune challenge and diet complexity on growth performance and acute-phase protein production in segregated early-weaned pigs.

Segregated early-weaned pigs (initially 4.0 kg and 14 +/- 1.5 d of age) were used to quantify the effects of lipopolysaccharide (LPS)-induced immune challenge and nursery diet complexity (complex, medium, and simple) on growth performance and haptoglobin production. Three treatments of immune challenge consisted of pigs given ad libitum access to feed (control), challenged with LPS and given ad libitum access to feed (LPS-challenged), or pair-fed to receive the same amount of feed as the LPS-challenged pigs (pair-fed). The absence of interactions (P > .10) between diet complexity and immune challenge with LPS indicated that the responses were independent. Control pigs were the heaviest (P < .01), LPS-challenged the lightest (P < .01), and pair-fed intermediate in weight on d 18 after weaning. Approximately two thirds of the decreased growth of LPS-challenged pigs was due to decreased ADFI and one third was due to decreased feed efficiency (G/F). Pigs fed the complex diet were heaviest (P < .05), and pigs fed the simple diet were lightest (P < .05) on d 18 after weaning. The increased growth of pigs fed the complex compared with those fed the medium diet was due to the increased ADFI of the former. The decreased growth of pigs fed the simple diet compared with those fed the medium or complex diets was due to both decreased ADFI and G/F. The LPS-challenged pigs had increased (P < .01) haptoglobin concentrations, suggesting that inflammatory cytokine production was higher in immune-challenged pigs. These data suggest that LPS immune challenge caused decreased growth by decreasing ADFI and altering nutrient partitioning and that growth responses to diet complexity are independent of immune challenge.

Acute-Phase Proteins↗

Influence of recombinant bovine interleukin-1 beta and interleukin-2 in pigs vaccinated and challenged with Streptococcus suis.

An experiment was conducted to determine the adjuvanticity of recombinant bovine IL-1 beta (rBoIL-1 beta) and recombinant bovine IL-2 (rBoIL-2) administered in conjunction with a single Streptococcus suis vaccination in pigs. Sixty 4-week-old pigs were allotted to eight groups: nonvaccinated controls; vaccinated controls; rBoIL-beta at 0.1, 1, and 10 micrograms kg-1; rBoIL-2 at 2.5, 25, and 250 micrograms kg-1. All pigs (except nonvaccinated controls) were vaccinated on Day 0 with a commercial Streptococcus suis vaccine (serotypes 1 and 2). At vaccination, pigs were injected intramuscularly with their respective cytokine treatments. Pigs received additional cytokine injections on 2 consecutive days. On Day 21, all pigs were challenged intravenously with 3.2 x 10(9) colony forming units of a log phase culture of S. suis (serotype 2). The highest dose of rBoIL-1 beta exceeded the maximum tolerable dose for the cytokine; however, this dose of rBoIL-1 beta protected pigs from the S. suis challenge. Pigs administered rBoIL-1 beta at 10 micrograms kg-1 had higher antibody responses to S. suis, less severe clinical signs of the disease after challenge, better growth performance during the infection, and less severe gross pathological lesions caused by the bacteria. No pigs in this treatment group died from the bacterial challenge. These data suggest that rBoIL-1 beta (10 micrograms kg-1), administered intramuscularly for 3 consecutive days at vaccination, is more effective than a single S. suis vaccination alone in protecting pigs against a S. suis challenge.

Adjuvants, Immunologic↗

Influence of dietary beta-glucan on growth performance, nonspecific immunity, and resistance to Streptococcus suis infection in weanling pigs.

Three experiments, using 344 pigs, were conducted to evaluate the influence of beta-glucan on growth performance, neutrophil and macrophage function, haptoglobin production, and resistance to Streptococcus suis challenge in weanling pigs. In Exp. 1, 144 pigs were used to evaluate the influence of .1% dietary beta-glucan in a soybean meal- or milk protein-based diet on growth performance and neutrophil function. Pigs fed beta-glucan from d 7 to 14 after weaning had lower ADFI (P < .01) and, although not significant, ADG was lower for pigs fed beta-glucan than for pigs fed control diets. However, no differences were observed in growth performance or neutrophil function for pigs fed control or diets containing beta-glucan from d 7 to 35 after weaning. Experiment 2 was a 28-d growth assay in which pigs were fed a diet with or without .1% beta-glucan, containing 7.5% spray-dried plasma protein and 25% dried whey from d 0 to 14 after weaning. Pigs then were fed corn-soybean mealbased diets containing 2.5% spray-dried blood meal and 10% dried whey. No differences in growth performance were observed. Experiment 3 was a 35-d assay to evaluate growth performance, neutrophil and macrophage function, and plasma haptoglobin concentration. Pigs were challenged on d 28 postweaning with intravenous S. suis. In Exp. 3, pigs were fed diets without or with .025 or .05% beta-glucan. Dietary beta-glucan did not influence neutrophil or macrophage function. However, pigs fed diets containing .025% beta-glucan had increased (P < .05) ADG and ADFI and were heavier (P < .05) on d 28 after weaning than pigs fed the control diet. No differences in feed efficiency (G/F) were detected between treatments. Pigs fed beta-glucan had decreased (P < .10) plasma haptoglobin on d 14, 21, and 28 after weaning. However, Fisher's Exact test revealed that more (P < .04) pigs fed a diet containing .025% beta-glucan died by d 12 after challenge with S. suis. In conclusion, these data suggest the existence of a complex interaction involving growth performance and resistance to S. suis in pigs fed .025% beta-glucan.

Aging↗

The effect of dietary lysine on growth, carcass composition, and lipid metabolism in high-lean growth gilts fed from 72 to 136 kilograms.

One hundred fourteen high-lean growth gilts (72.5 kg BW) were used to determine the apparent digestible lysine requirement for maximum growth performance and carcass protein deposition rate from 72.5 to 136 kg BW. The experiment was a randomized complete block design with initial BW used to establish blocks. Six dietary treatments were included, ranging from .44 to .94% (.10% increments) apparent digestible lysine (.62 to 1.13% total lysine) with six replicate pens per treatment and three pigs per pen. Pig weights and feed consumption were collected weekly to determine ADG, ADFI, and gain: feed ratio (G/F). Six gilts were slaughtered at 72.5 kg BW to determine initial carcass composition. When the mean weight of pigs in a pen reached 104 or 136 kg, one pig per pen was selected (closest to 104 or 136 kg, respectively) and slaughtered for determination of carcass measurements and composition. From 72.5 to 104 kg and from 104 to 136 kg, ADG and G/F increased (linear, P < .05; quadratic, P < .10, respectively) as apparent digestible lysine increased. From 72.5 to 136 kg, G/F increased (quadratic, P < .10) as apparent digestible lysine increased. Average backfat thickness and longissimus muscle area at 104 kg were not influenced (P > .10) by apparent digestible lysine. However, average backfat thickness increased (quadratic, P < .05) with increasing digestible lysine for gilts slaughtered at 136 kg. Carcass CP accretion was not influenced (P > .10) from 72.5 to 104 kg but tended to increase (linear, P < .10) from 72.5 to 136 kg as digestible lysine increased. Plasma and longissimus muscle cholesterol concentrations were unaffected (P > .10) by increasing digestible lysine. These results suggest that high-lean growth gilts require greater dietary lysine than current NRC (1988) estimates to maximize ADG, G/F, and carcass CP accretion from 72.5 to 104 and from 104 to 136 kg.

Animals↗

The effect of dietary methionine and its relationship to lysine on growth performance of the segregated early-weaned pig.

Two experiments were conducted to determine the dietary methionine requirement and the appropriate methionine:lysine for the segregated early weaned-weaned pig. In Exp. 1, 435 crossbred pigs (9.5 +/- 4 d of age and 3.5 kg BW) were fed diets (1.8% lysine, .62% cystine) containing 10% spray-dried plasma protein (SDPP) and 1.75% spray-dried blood meal (SDBM) from day 0 to 21 postweaning. Pigs were feed one of six dietary treatments from .36% to .56% total dietary methionine (.317 to .517% apparent digestible methionine). From d 0 to 7 and d 0 to 21 postweaning, ADG and gain:feed ratio (G/F) increased (linear, P < .01, P < .05, respectively) as dietary methionine increased. In Exp. 2, 350 crossbred pigs (9.0 +/- 2 d of age and 3.8 kg BW) were used to determine the appropriate methionine:lysine ratio for the segregated early-weaned pig in a 2 x 5 factorial arrangement. Two lysine levels (1.8 and 1.4%) and five methionine levels within each lysine level were used to obtain methionine:lysine ratios ranging from 21.5 to 33.5%. From d 0 to 21 postweaning, pigs were assigned to one of 10 dietary treatments containing 25% dried whey, 12% lactose, 7.5% SDPP, 6.0% select menhaden fish meal, and 1.75% SDBM. No methionine x lysine interactions were observed (P > .10). From d 0 to 7 postweaning, increasing dietary methionine improved (quadratic, P < .01) ADG and ADFI regardless of dietary lysine. From d 0 to 14 postweaning, increasing dietary methionine improved ADG (quadratic, P < .01), ADFI quadratic, P =.02), and G/F (quadratic, P < .10). Inflection point analysis projected maximum ADG at methionine:lysine ratios of 27 and 27.5% for pigs fed 1.4 and 1.8% lysine, respectively. Cumulative (d 0 to 21 postweaning) ADG, ADFI, and G/F were improved (quadratic, P < .05) by increasing dietary methionine. Increasing dietary lysine improved (P < .01) ADG and G/F from d 0 to 7, from d 0 to 14, and for the overall experiment. In conclusion, a diet with 1.8% total lysine that includes spray-dried blood products must contain .48 to .52% total dietary methionine (.437 to .477% apparent digestible) or 27.5% of total lysine to maximize growth performance of pigs from d 0 to 21 postweaning (3.5 to 12 kg BW).

Aging↗

Added dietary methionine in starter pig diets containing spray-dried blood products.

Two experiments were conducted to determine the dietary methionine requirement of weanling pigs fed diets containing spray-dried porcine plasma and(or) blood meal in a phase-feeding program. In Exp. 1, 216 crossbred pigs (21 +/- 2 d of age and 4.9 kg BW) were fed diets (1.6% lysine, .52% cystine) containing 10% spray-dried porcine plasma and 1.75% spray-dried blood meal from d 0 to 21 postweaning. Pigs were fed one of six dietary treatments ranging from .28 to .48% total dietary methionine (.225 to .425% apparent digestible methionine). From d 0 to 14 and d 0 to 21 postweaning, ADG, ADFI, and gain:feed ratio (G:F) increased (quadratic, P < .01) as dietary methionine increased. Inflection point analysis projected .42 and .41% total dietary methionine to maximize ADG and G:F from d 0 to 14 and d 0 to 21 postweaning, respectively. In Exp. 2,216 crossbred pigs (21 +/- 3 d of age and 5.6 kg BW) were used to determine the dietary methionine requirement from d 7 to 28 postweaning. All pigs were fed the same diet (1.6% lysine, .44% methionine, .52% cystine) from d 0 to 7 postweaning. From d 7 to 28, pigs were assigned to one of six dietary treatments (1.3% lysine, .46% cystine) containing 10% dried whey and 3% spray-dried blood meal. Total dietary methionine levels ranged from .27 to .42% (.249 to .399% apparent digestible methionine). From d 7 to 14 postweaning, increasing dietary methionine increased (quadratic, P < .05) ADG, ADFI, and G:F (.34 to .35% total methionine projected by inflection point analysis).(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids, Essential↗

Influence of interleukin-1 on neutrophil function and resistance to Streptococcus suis in neonatal pigs.

Nonspecific immunity is usually lower in neonates than adults. Consequently, enhancing the neonate's nonspecific immune capability may be beneficial for the health and growth performance of young animals. We conducted two experiments in which neonatal pigs were injected with recombinant bovine interleukin-1 beta (rBoIL-1 beta) at 9 to 11 days of age. Three consecutive daily injections of rBoIL-1 beta increased neutrophil and monocyte numbers, which remained elevated until the animals were challenged with Streptococcus suis at 19 days of age. Neutrophil bactericidal activity was greater in interleukin-1-treated pigs than in saline-injected controls. At lower ratios of effector to target cells, neutrophil-mediated, antibody-dependent cellular cytotoxicity was increased in neonates treated with IL-1. However, natural killer cell activity and neutrophil production of superoxide anion were not affected by treatment with IL-1. Expression of CD18 was increased transiently on neutrophils from IL-1-treated pigs at 15 days of age. Severity of the streptococcal infection was less in pigs that were treated with IL-1 at 9 to 11 days of age. These data suggest that IL-1 treatment in neonates may augment nonspecific immune function and disease resistance.

Animals↗

The effects of spray-dried blood meal on growth performance of the early-weaned pig.

A total of 1,956 weanling pigs were used in five experiments to evaluate spray-dried blood meal (SDBM) in starter pig diets. In Exp. 1, 432 weanling pigs (initially 6.9 kg BW and 21 d of age) were used to evaluate different protein sources in the d 7 to 28 postweaning diet. Pigs were fed a control diet containing 5% select menhaden fish meal or diets with 3.88% spray-dried porcine plasma, 2.49% SDBM (porcine), 5.74% soy protein concentrate, 5.74% moist extruded soy protein concentrate, or L-lysine.HCl and DL-methionine replacing select menhaden fish meal on an ideal protein basis. Pigs fed diets containing the spray-dried blood products had higher (P < .06) mean ADG than pigs fed the other protein sources. In Exp. 2, 744 weanling pigs (initially 5.8 kg BW and 21 d of age) were used to determine the effects of 0, 1, 2, 3, 4, or 5% SDBM (bovine) in the d 7 to 28 postweaning diet. Pigs fed increasing SDBM had greater (quadratic, P < .01) ADG and improved gain:feed ratio (G/F). Inflection point analysis projected optimum ADG and G/F at 1.9% SDBM. In Exp. 3, 216 weanling pigs (initially 10.9 kg BW and 42 d of age) were used to determine the effects of 0, .5, 1, 1.5, 2, and 2.5% SDBM (bovine) in the d 21 to 42 postweaning diet. Pigs fed increasing SDBM had decreased (linear, P < .05) ADG and G/F. In Exp. 4 and 5, 144 and 180 weanling pigs (initially 5.3 and 6.2 kg BW and 24 and 21 d of age, respectively) were used to evaluate either 2.5% spray-dried porcine, spray-dried bovine, or flash-dried bovine blood meal (Exp. 4) or 2.5% spray-dried bovine or spray-dried avian blood meal (Exp. 5). Pigs fed diets containing the spray-dried blood meals had improved ADG and G/F (P < .01) compared with pigs fed flash-dried blood meal. However, no differences (P > .10) were observed among treatments when pigs were fed spray-dried blood meals from different species. We conclude that spray-dried bovine, porcine, and avian blood meal are effective protein sources in starter pig diets (d 7 to 28 postweaning). However, SDBM is not necessary in the diets of older pigs (d 21 to 42 postweaning) for maximum growth performance.

Animal Feed↗

The effects of diets formulated on an ideal protein basis on growth performance, carcass characteristics, and thermal balance of finishing gilts housed in a hot, diurnal environment.

Forty-eight finishing gilts (initial BW = 70.6 +/- .95 kg) were randomly assigned to one of eight experimental treatments in a 2 x 2 x 2 factorial arrangement with main effects including dietary lysine (.60 vs 1.00%), source of amino acid fortification (intact protein vs synthetic amino acids formulated on an ideal protein basis), and environmental temperature (thermoneutral [TN]: 20 degrees C vs hot, diurnal [HD]: 27.7 to 35 degrees C). The ideal protein diets were formulated by using corn and soybean meal to meet the fifth-limiting amino acid; synthetic lysine, threonine, tryptophan, methionine, or isoleucine were added to meet the gilts' estimated requirements. The ratios of other total amino acids relative to lysine were as follows: threonine, 66%; tryptophan, 17%; methionine and cystine, 56%; and isoleucine, 63%. Average daily gain, ADFI, and feed efficiency (G/F) were similar for gilts fed the intact and those fed the ideal proteins diets (P > .10). Increasing dietary lysine improved d 0 to 14 ADG (P < .01), but no differences were observed for the overall experiment. Gilts in the HD environment ate less feed and had lower ADG than gilts in the TN environment (P < .01). A temperature x lysine interaction was observed (P < .02) for G/F. Increasing dietary lysine had no effect on G/F of gilts in the TN environment but improved G/F of gilts in the HD environment. Gilts fed the intact protein diets had higher (P < .01) N intake and plasma urea concentrations. Gilts fed the ideal protein diets had lower (P < .05) plasma essential amino acids, with the exception of lysine. Carcass protein and lipid contents were improved (P < .01) for gilts in the HD environment and for those fed 1.00% lysine. Backfat thickness and longissimus muscle area (P < .01) were improved and lipid accretion rate tended to decrease (P < .08) in gilts fed 1.00% lysine. The source of amino acid fortification did not influence carcass characteristics (P > .10). Rectal, skin, and ear temperatures were higher for gilts in the HD environment (P < .05). Metabolic heat production was elevated by feeding gilts the ideal protein diets (P < .03). In conclusion, increased dietary lysine improved G/F and carcass leanness in gilts to a greater extent in HD than in TN environments. However, no improvements in growth performance or carcass traits resulted from feeding ideal protein diets.

Amino Acids↗

Effects of the interrelationship between genotype, sex, and dietary lysine on growth performance and carcass composition in finishing pigs fed to either 104 or 127 kilograms.

One hundred twenty pigs (initially 44 kg BW) were used to determine effects of the interrelationship between genotype, sex, and dietary lysine on growth performance and carcass composition in a 2 x 2 x 2 factorial arrangement. Genetic comparisons were made between pigs characterized with either a high or medium potential for lean tissue gain. Within genotype, barrows and gilts were separately fed either a .90 or .70% lysine diet until the mean weight of pigs in each pen of three reached 104 kg. One pig per pen was slaughtered to determine carcass characteristics and chemical composition. From 104 to 127 kg, dietary lysine was lowered to .75 or .55% for pigs fed .90 or .70% dietary lysine, respectively. When the pigs' mean weight met or exceeded 127 kg, both pigs were slaughtered to determine carcass characteristics and chemical composition. Carcass length, longissimus muscle area, average backfat thickness, and 10th rib fat depth were measured 24 h postmortem on the chilled carcasses. The right side of each carcass was then ground and chemically analyzed to determine protein and lipid accretion rates. No interactions were detected from 44 to 104 kg; therefore, main effect means will be discussed. At 104 kg, high-lean pigs had increased ADG (P < .01) and gain:feed ratio (G/F; P < .05) compared with medium-lean pigs. Barrows had increased (P < .05) ADG and ADFI but exhibited a poorer (P < .01) G/F than gilts. Pigs fed .90% lysine had improved (P < .01) ADG compared with pigs fed .70% lysine.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Interactive effects among porcine somatotropin, the beta-adrenergic agonist salbutamol, and dietary lysine on growth performance and nitrogen balance of finishing swine.

An experiment was conducted to evaluate the interactive effects among porcine somatotropin (pST), salbutamol, and dietary lysine on growth performance, nitrogen balance, and carcass characteristics of finishing barrows (n = 32; 62.8 kg initially). Two replicate 32-d studies were set up in a split-plot design to evaluate singular and combined use of pST (0 or 4 mg/d) and salbutamol (0 or 2.75 ppm of the diet) as whole-plot treatments and diets containing .8, 1.2, 1.6, or 2.0% lysine as subplot treatments. Dietary lysine levels were administered within subplots in a 4 x 4 Latin square with pigs allowed 4 d of adjustment to diets followed by 4 d of urine and feces collection for determination of N retention and apparent digestibility of DM and N. Interactions between lysine and salbutamol were not found (P > .16). A pST x lysine interaction (P < .05) resulted in ADG being maximized at 1.2% lysine for pST-treated pigs (lysine quadratic, P < .02) but decreased linearly (P < .02) with increasing lysine for pigs receiving buffer. Pigs injected with 4 mg/d of pST had improved gain:feed (G:F) up to 1.2% lysine (lysine quadratic, P < .05), but no further increase to 2% lysine, whereas pigs injected with buffer showed no benefit from increased lysine (pST x lysine, P < .06). Pigs receiving buffer had greater increases in plasma urea N (PUN) as lysine increased than those receiving pST (pST x lysine, P < .002), but PUN was reduced by pST (P < .001) regardless of lysine level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

Influence of dietary lysine on growth and carcass composition of high-lean-growth gilts fed from 34 to 72 kilograms.

One hundred eight high-lean-growth gilts (34.4 kg BW) were used to determine the dietary lysine requirement to maximize growth, carcass characteristics, and protein accretion from 34 to 72.5 kg BW. The experiment was a randomized complete block design; initial BW served as the blocking factor. Six dietary treatments were included, ranging from .54 to 1.04% (.10% increments) digestible lysine (.69 to 1.25% total lysine). Pigs were housed in pens of three, with six replicate pens per treatment. Pig weights and feed consumption were collected weekly to calculate ADG, ADFI, and gain:feed (G/F). Initially, five pigs were slaughtered to determine baseline carcass composition. When the mean weight for pigs in a pen reached 55 and 72.5 kg, one pig per pen was randomly selected and slaughtered for carcass measurements. The right side of each carcass was ground twice and sampled to determine carcass composition and tissue accretion rates. Average daily gain was increased by dietary lysine from 34 to 55 kg (linear, P < .01), from 55 to 72.5 kg (linear, P < .10), and from 34 to 72.5 kg (linear, P < .01). Although ADFI from 34 to 55 and from 55 to 72.5 kg was not influenced by dietary lysine, ADFI for the entire experiment tended to decrease (quadratic, P < .10) as digestible lysine increased. Increased dietary lysine resulted in improved G/F from 34 to 55 kg (linear, P < .01) and from 55 to 72.5 and 34 to 72.5 kg (quadratic, P < .01). Average backfat thickness was not influenced by dietary lysine at 55 kg but decreased (linear, P < .05) as dietary lysine increased at 72.5 kg. At 55 kg, longissimus muscle area was larger (linear, P < .05) for gilts fed increased digestible lysine. However, longissimus muscle area was similar for all treatments at 72.5 kg. Gilts fed increased digestible lysine had greater CP accretion from 34 to 55 kg (linear, P < .01), 55 to 72.5 kg (linear, P < .05; quadratic, P < .10), and from 34 to 72.5 kg (quadratic, P < .05). Based on the feed intake observed in this study, the high-lean-growth gilt requires at least 22 g/d total lysine intake from 34 to 72.5 kg to maximize CP accretion.

Adipose Tissue↗

The effect of spray-dried porcine plasma on growth performance in the early-weaned pig.

A total of 904 weanling pigs were used to investigate the effects of 1) spray-dried porcine plasma (SDPP), 2) blends of SDPP and spray-dried blood meal (SDBM), and 3) added dietary methionine in a SDPP-based diet on starter pig performance. In Exp. 1, 534 weanling pigs (initially 6.4 kg and 21 +/- 2 d of age) were used to determine the effects of either 0, 2, 4, 6, 8, or 10% SDPP and lactose as a replacement for dried skim milk in the Phase I diet (d 0 to 14 postweaning). All pigs were fed the same diet from d 14 to 28 postweaning. Average daily gain from d 0 to 14 increased (linear, P < .01) with increasing SDPP. From d 14 to 28, ADG decreased (linear, P < .03) as level of SDPP fed during Phase I increased. However, for d 0 to 28, ADG was increased (linear, P < .01) with increasing SDPP in the Phase I diet. Feed intake increased with increasing SDPP from d 0 to 14 and d 0 to 28 (quadratic, P < .04 and P < .08, respectively); however, gain/feed (G/F) was not affected. In Exp 2, 298 weanling pigs (initially 5.5 kg and 19 +/- 2 d of age) were used to determine the effects of replacing SDPP with SDBM in the Phase I diet. Pigs were fed either a diet containing 10% SDPP or diets with SDBM replacing 25, 50, 75, or 100% of the lysine provided by the SDPP.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗