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M D Tokach

Publications and source records attributed to M D Tokach.

At least 37 records · Page 2Linked to original sources
PubMed2003

Effects of increasing dietary L-carnitine on growth performance of weanling pigs.

Four experiments were conducted to evaluate the effects of supplementing graded levels (0 to 100 ppm) of L-carnitine to the diet of weanling pigs on growth performance during a 34- to 38-d experimental period. A fifth experiment was conducted to determine the effects of addition of L-carnitine to diets with or without added soybean oil (SBO) on growth performance. In Exp. 1, 128 pigs (initial BW = 5.5 kg) were allotted to four dietary treatments (six pens per treatment of four to six pigs per pen). Dietary treatments were a control diet containing no added L-carnitine and the control diet with 25, 50, or 100 ppm of added L-carnitine. In Exp. 2, 3, and 4, pigs (4.8 to 5.6 kg of BW) were allotted to five dietary treatments consisting of either a control diet containing no added L-carnitine or the control diet with 25, 50, 75, or 100 ppm of added L-carnitine. All diets in Exp. 1 to 4 contained added soybean oil (4 to 6%). There were seven pens per treatment (four to five pigs per pen) in Exp. 2, whereas Exp. 3 and 4 had five and six pens/treatment (eight pigs per pen), respectively. In general, dietary carnitine additions had only minor effects on growth performance during Phases 1 and 3; however, dietary L-carnitine increased (linear [Exp. 1], quadratic [Exp. 2 to 4], P < 0.03) ADG and gain:feed (G:F) during Phase 2. The improvements in growth performance during Phase 2 were of great enough magnitude that carnitine addition tended to increase ADG (linear, P < 0.10) and improve G:F (quadratic, P < 0.02) for the entire 38-d period. In Exp. 5, 216 weanling pigs (5.8 kg of BW) were allotted (12 pens/treatment of four to five pigs per pen) to four dietary treatments. The four dietary treatments were arranged in a 2 x 2 factorial with main effects of added SBO (0 or 5%) and added L-carnitine (0 or 50 ppm). Pigs fed SBO tended (P < 0.07) to grow more slowly and consumed less feed compared with those not fed SBO, but G:F was improved (P < 0.02). The addition of L-carnitine did not affect (P > 0.10) ADG or ADFI; however, it improved (P < 0.03) G:F. Also, the increase in G:F associated with L-carnitine tended to be more pronounced for pigs fed SBO than those not fed SBO (carnitine x SBO, P < 0.10). These results suggest that the addition of 50 to 100 ppm of added L-carnitine to the diet improved growth performance of weanling pigs. In addition, supplemental L-carnitine tended to be more effective when SBO was provided in the diet.

Aging↗
PubMed2002

Comparison of spray-dried blood meal and blood cells in diets for nursery pigs.

We used a total of 680 pigs to compare spray-dried blood meal and blood cells in nursery diets. In Exp. 1, 350 barrows (17 +/- 2 d of age at weaning) were used to compare three levels of spray-dried blood meal or blood cells (2.5, 5.0, and 7.5%) in the diet fed from d 5 to 19 postweaning (6.6 to 9.9 kg). Inclusion of either blood product improved ADG (P < 0.005) and G:F (P < 0.001) compared to pigs fed the control diet without added blood products. However, pigs fed spray-dried blood meal had greater ADG (P < 0.001), ADFI (P < 0.04), and G:F (P < 0.001) from d 0 to 7 compared to those fed blood cells. The greatest differences observed between the two blood products occurred at the 5 and 7.5% inclusion levels. No differences (P > 0.05) in growth performance were detected between the two blood products from d 7 to 14. In Exp. 2, 380 barrows (initial BW of 10.7 kg and 41 +/- 2 d of age) were used to determine lysine bioavailability of spray-dried blood meal and blood cells via the slope ratio procedure. With G:F ratio as the response criterion, blood meal and blood cells had similar lysine bioavailability relative to crystalline lysine. These experiments indicate that both blood products had similar lysine bioavailability, and that pigs fed spray-dried blood meal had greater performance during the initial 7 d (d 5 to 12 after weaning). However, as the pigs became heavier, there were no differences observed in performance of pigs fed either blood meal or blood cells.

Animal Feed↗
PubMed2002

Effects of providing a water-soluble globulin in drinking water and diet complexity on growth performance of weanling pigs.

Two experiments were conducted to evaluate the effects of providing a water-soluble globulin in the drinking water on growth performance of weanling pigs. In Exp. 1, 360 weanling pigs (5.0 +/- 1.2 kg; 17 +/- 3 d of age; PIC) were blocked by initial weight and allotted to one of six treatments in a 2 x 3 factorial arrangement. Treatments included three diet complexity regimens with or without water-soluble globulin (3 and 1.5% solutions; d 0 to 7 and d 0 to 14, respectively) provided in the drinking water. The 35-d study was divided into three phases (d 0 to 7, 7 to 14, and 14 to 35) with corresponding lysine levels of 1.6, 1.5, and 1.35%. Soybean meal replaced specialty protein and lactose sources to provide three different complexity regimens. From d 0 to 7, a water-soluble globulin x diet complexity interaction (P < 0.05) was observed for average daily gain (ADG) and gain:feed (G/F). Increasing diet complexity increased ADG and G/F for pigs provided water, whereas the medium diet complexity regimen optimized performance for pigs offered water-soluble globulin. From d 0 to 14, pigs fed the two more complex regimens had greater ADG and G/F (P < 0.01) than the pigs fed the least complex regimen. Pigs offered water-soluble globulin had decreased (P < 0.01) ADFI, but increased (P < 0.001) G/F from d 0 to 14. For overall performance (d 0 to 35), increasing diet complexity increased (P < 0.03) ADG and ADFI, whereas water-soluble globulin offered from d 0 to 14 had no effect. In Exp. 2, 360 weanling pigs (5.2 +/- 1.6 kg; 19 +/- 4 d of age) were used in a 21-d growth assay. The trial was arranged as a 2 x 3 factorial with pigs fed the low- or medium-complexity diets (Exp. 1) with water or a 3% solution of water-soluble globulin offered for 4 or 8 d after weaning. From d 0 to 4, pigs offered water-soluble globulin had increased (P < 0.001) ADG and G/F compared with pigs provided water, whereas from d 4 to 8, pigs provided water had increased (P < 0.05) ADG and G/F compared with pigs offered water-soluble globulin. Pigs fed the medium-complexity diet had increased ADG and G/F (d 4 to 8 and d 8 to 12) compared with pigs fed the low-complexity diet. From d 0 to 8 and d 0 to 21, pigs provided water-soluble globulin for 4 or 8 d after weaning had improved G/F compared with pigs provided water. Results demonstrate that providing water-soluble globulin through the water source of weanling pigs improves ADG and G/F immediately after weaning.

Animal Feed↗
PubMed2002

Effects of increasing dietary niacin on growth performance and meat quality in finishing pigs reared in two different environments.

We conducted two experiments to determine the effects of added dietary niacin on growth performance and meat quality in finishing pigs. Pigs were blocked by weight and assigned to one of six dietary treatments in both experiments. Dietary treatments consisted of a corn-soybean meal-based control diet (no added niacin) or the control diet with 13, 28, 55, 110, or 550 mg/kg of added niacin. In Exp. 1, pigs were housed at the Kansas State University research from with two pigs per pen (six pens per treatment per sex). In Exp. 2, pigs were housed with 26 pigs per pen (four pens per treatment per sex) in a commercial research barn. In Exp. 1, 144 pigs (initially 51.2 kg) were fed diets in two phases (d 0 to 25 and 25 to 62) that were formulated to 1.00 and 0.75% lysine, respectively. In Exp. 2, 1,248 pigs (initially 35.9 kg) were fed diets in four phases (d 0 to 28, 29 to 56, 57 to 84, and 85 to 117), with corresponding total lysine concentrations of 1.25, 1.10, 0.90, and 0.65% lysine, respectively. Added fat (6.0%) was included in the first three phases. In Exp. 1, average daily feed intake tended (quadratic, P < 0.07) to increase then return to values similar to control pigs as dietary niacin increased. Longissimus muscle (LM) 24-h pH (longissimus of pigs fed added niacin) tended to increase (control vs niacin, P < 0.06) for pigs fed added niacin. In the commercial facility (Exp. 2), increasing added niacin improved gain:feed (quadratic, P < 0.01) and subjective color score, and ultimate pH (linear, P < 0.01). Added niacin also decreased (linear, P < 0.04) carcass shrink, L* values, and drip loss percentage. Results from these two studies show that 13 to 55 mg/kg added dietary niacin can be fed to pigs in a commercial environment to improve gain:feed. It also appears that pork quality, as measured by drip loss, pH, and color, may be improved by higher concentrations of added dietary niacin.

Animal Feed↗
PubMed2002

Two on-farm data collection methods to determine dynamics of swine compositional growth and estimates of dietary lysine requirements.

An experiment was conducted to evaluate the use of two real-time ultrasound data-collection methods to develop a dynamic assessment of live weight growth, protein and lipid accretions, and lysine requirement curves on two commercial swine operations. For the first method, pigs (40 barrows and 40 gilts) were weighed (ranging from 18 to 121 kg) and scanned ultrasonically to collect backfat depth and longissimus muscle area measurements every 3 wk in the finishing facility on two farms (serial method). For the second method, pigs (200 gilts and 200 barrows) of similar corresponding ages on the same two farms were weighed and scanned on 1 d (mass scan) at three different times (February, April, and May). Thirty-two pigs/sex were measured at approximately the same ages as with the serial scans. Pigs on farm 1 grew faster and had smaller backfat depths and larger longissimus muscle areas (P < 0.01) than those on farm 2, irrespective of method. These measurements were used to predict empty-body protein and lipid contents using nonlinear functions, which then were converted to accretion rates and lysine requirements at each BW. Protein accretion (g/d) and daily lysine requirements increased and then decreased for each sex on each farm and were higher on farm 1 than on farm 2. Data from the individual mass scans had larger standard errors for modeled live weight growth than data from the serial scans. Combining data from the three mass scans yielded growth curves with standard errors similar to those for the curves from the serial scans. For the protein accretion curves, the standard errors of the combined mass scans were approximately 20% lower than the standard errors of the serial scans. The standard errors for the modeled lysine:calorie ratio requirement from the serial scans were approximately 1% of the requirement at each BW. These results indicated that either the serial or mass scan data-collection method is a practical means of determining on-farm growth and daily protein and lipid accretion rates, which can be used to determine the farm-specific lysine requirements of growing-finishing pigs.

Adipose Tissue↗
PubMed2002

Effects of modified tall oil and vitamin E on growth performance, carcass characteristics, and meat quality of growing-finishing pigs.

Crossbred barrows (n = 72) were used to evaluate effects of diet supplementation with modified tall oil (MTO; 0.0 or 0.50%) and vitamin E (0, 22, or 110 IU/kg) on growth performance, carcass traits, and longissimus muscle (LM) quality traits of finishing pigs. Pigs were blocked by ancestry and initial BW and allotted randomly to treatments in a 2 x 3 factorial. Corn-soybean meal-based diets were fed in two phases: 45.5 to 81.6 (1.00% lysine) and 81.6 to 114.6 (0.75% lysine) kg BW with no added fat. From 45.5 to 81.6 kg, pigs fed MTO had greater ADG (P = 0.03) regardless of added vitamin E; otherwise, treatment did not affect growth performance. Carcasses from pigs fed MTO had reduced (P < 0.05) average backfat (2.76 vs 2.92 cm) and firmer bellies compared to those fed no MTO. Boneless loins were cut into 2.54-cm chops at 7 d postmortem and evaluated for display color, thiobarbituric acid-reactive substance (TBARS), Warner-Bratzler shear force (WBSF), and sensory panel ratings. Visual color was similar (P > 0.05) among treatments at 0 and 1 d of display. At 4 and 6 d of display chops from pigs fed MTO with 110 IU vitamin E/kg had less deterioration (P < 0.05) than chops from pigs fed MTO with 0 IU vitamin E/kg and 0.0% MTO with 22 or 110 IU vitamin E/kg. The CIE L*, a*, b* and spectral values also suggested a delay in color deterioration for chops from pigs fed MTO with 110 IU vitamin E/kg. At 6 and 8 d of display, chops from pigs fed 110 IU vitamin E/kg had lower (P < 0.05) L* values than those from pigs fed 0 or 22 IU vitamin E/kg, and higher (P < 0.05) a* values than those from pigs fed 0 IU vitamin E/kg feed. A higher (P < 0.05) %R630/%R580 (indicator of more oxymyoglobin) was observed for chops from pigs fed MTO with 110 IU vitamin E/kg than those from pigs fed 0.0% MTO with 22 or 110 IU vitamin E/kg and MTO with 0 IU vitamin E/kg. Chops from pigs fed MTO with 110 IU vitamin E/kg had lower (P < 0.05) TBARS values than those from pigs fed MTO with 0 IU vitamin E/kg. No differences (P > 0.05) were detected among treatments for WBSF or sensory evaluations. The addition of MTO in swine diets improved belly firmness and reduced backfat, and feeding MTO with high levels of vitamin E extended display life without affecting palatability of LM chops.

Animal Feed↗
PubMed2002

Nutrient composition of Kansas swine lagoons and hoop barn manure.

A total of 312 samples in two experiments were analyzed to determine mean nutrient concentrations of swine lagoons and hoop barns in Kansas. First, in a retrospective study (Exp. 1), we obtained 41 sample analyses from the Kansas Department of Agriculture of sow, nursery, wean-to-finish, finish, and farrow-to-finish operations in 1999. The average total N concentration was 899 ppm (SD = 584 ppm), while the total P concentration was 163 ppm (SD = 241 ppm). In an attempt to reduce the variation, we conducted a prospective experiment standardizing collection procedure, laboratory techniques, phase of production, and season of year to more accurately determine the nutrient concentrations of swine lagoons in Kansas. In Exp. 2, we used 236 lagoon and 35 hoop barn manure samples taken in 2000 from Kansas swine operations to determine the impacts of production phase and season of the year on nutrient concentration. The different operations with swine lagoons were: 1) sow; 2) nursery; 3) wean-to-finish; 4) finish; and 5) farrow-to-finish, with a total of 9, 8, 7, 10, and 8 lagoons sampled from each phase of production, respectively. The total N and P concentrations from lagoons were 1,402 and 204 ppm, respectively, averaged over all samples. Concentrations of total N were higher in wean-to-finish and finishing lagoons (P < 0.05) compared with sow and farrow-to-finish lagoons. Lagoon analyses also revealed that N concentrations decreased (linear, P < 0.05) during the summer and fall compared with winter and early spring. The concentration of P was greater (P < 0.05) for wean-to-finish compared with farrow-to-finish lagoons. Phosphorus concentrations for all lagoons increased (quadratic, P < 0.05) from February until June, but then declined steady throughout the remainder of the year. Average total N and P in hoop barns were 8,678 and 4,364 ppm, respectively. No seasonal changes in N and P concentrations were observed in manure from hoop barns. Season and type of production phase affect the nutrient content of Kansas swine lagoons, and producers will benefit from obtaining individual analyses from their lagoons when developing nutrient management plans rather than utilizing published reference values.

Animal Husbandry↗
PubMed2002

Effects of increasing L-lysine HCl in corn- or sorghum-soybean meal-based diets on growth performance and carcass characteristics of growing-finishing pigs.

We conducted three experiments to determine the effects of increasing L-lysine HCl in growing-finishing pig diets. Experiments 1 and 2, conducted at the Kansas State University research center, each used 360 growing-finishing pigs with initial BW of 56 and 63 kg, respectively. Dietary treatments were sorghum- (Exp. 1) or corn- (Exp. 2) soybean meal-based and consisted of a control (no L-lysine HCl) or 0.15, 0.225, and 0.30% L-lysine HCl replacing lysine provided by soybean meal. Experiment 3 was conducted in a commercial research facility using a total of 1,200 gilts with an initial BW of 29 kg. Pigs were allotted to one of eight dietary treatments fed in four phases. These consisted of a positive control diet with no added L-lysine HCl and the control diet with 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30% L-lysine HCl replacing the lysine provided by soybean meal. The eighth dietary treatment was a negative control diet with no added L-lysine HCl and formulated to contain 0.10% less total lysine than the other treatments to ensure that dietary lysine was not above required levels. In Exp. 1, increasing L-lysine HCl decreased (linear, P < 0.01) ADG, feed efficiency (G:F), and percentage lean and increased (linear, P < 0.01) backfat depth. In Exp. 2, increasing L-lysine HCl decreased (quadratic, P < 0.03) ADG, G:F, and ADFI, but carcass characteristics were not affected. In Exp. 3, increasing L-lysine HCl decreased ADG (linear, P < 0.01) and G:F (quadratic P < 0.03). In all three experiments, the greatest negative responses were observed when more than 0.15% L-lysine HCl was added to the diet. Therefore, unless other synthetic amino acids are added to the diet, no more than 0.15% L-lysine HCl should replace lysine from soybean meal in a corn- or sorghum-soybean meal-based diet to avoid deficiencies of other amino acids. Based on the content of diets containing 0.15% Lysine-HCl, it appears the requirements for methionine plus cystine expressed as ratios relative to lysine are not greater than 50% during the early growing-finishing period (30 to 45 kg) and 62% during the late finishing period (90 to 120 kg) on a true digestible basis. For similar periods, the ratio requirements for threonine are not greater than 59% and 64% on a true digestible basis.

Amino Acids↗
PubMed2001

Effects of dietary fat on growth performance and carcass characteristics of growing-finishing pigs reared in a commercial environment.

We conducted two experiments to evaluate the effects of added choice white grease on performance and carcass merit of barrows and gilts reared under commercial conditions. Pigs were housed either 20 (Exp. 1) or 25 (Exp. 2) per pen and were provided 0.67 m2 of pen space per pig. Diets were based on corn and soybean meal and fed in a meal form. The proportion of soybean meal was increased in diets with added fat to maintain the same calorie:lysine ratio in all diets within a weight phase. In Exp. 1, 480 pigs were fed diets with 0, 2, 4, or 6% fat. Total lysine contents of the control diets were 1.21, 0.88, and 0.66% during the weight phases 36 to 59, 59 to 93, and 93 to 120 kg, respectively. Gain:feed was increased linearly (P < 0.01) due to fat addition in all weight intervals and over the total experiment. The effect of added fat on ADG was not consistent among the weight phases; a linear (P < 0.01) improvement was found from 36 to 59 kg, but no effect was found during the heavier weight phases. Over the total experiment, however, ADG was improved (P < 0.01) linearly. Carcass traits were not affected by treatment. Experiment 2 used 900 pigs to evaluate possible carryover effects on performance and carcass merit from feeding 6% fat. The experiment was divided into four phases: 25 to 45, 45 to 70, 70 to 90, and 90 to 115 kg; lysine contents of the control diets fed in each phase were 1.23, 1.05, 0.81, and 0.63%, respectively. The six treatments consisted of no added fat throughout the experiment or 6% added fat fed from 25 to 45 kg, 25 to 70 kg, 25 to 90 kg, 25 to 115 kg, or 45 to 70 and 90 to 115 kg. Carryover effects for ADG and G:F (P < 0.07) were found for the 90- to 115-kg interval and for ADFI and ME intake (P < 0.05) for the 45- to 70- and 70-to 90-kg intervals. When fat was added in the previous weight interval, ADG and G:F were improved and ADFI and ME intake were decreased in the subsequent weight interval. Pigs fed fat from 25 to 115 kg had more (P < 0.05) backfat and lower (P < 0.05) carcass leanness than pigs on the other treatments. These data suggest that fat can be added or removed from diets of growing-finishing pigs without any detrimental carryover effects. In fact, the positive carryover effect on ADG and G:F from 95 to 115 kg suggests that feeding fat from 25 to 95 kg will maximize performance over the total growing-finishing period but minimize any detrimental effects of added fat on carcass leanness.

Animal Feed↗
PubMed2001

Dietary L-carnitine suppresses mitochondrial branched-chain keto acid dehydrogenase activity and enhances protein accretion and carcass characteristics of swine.

A trial was conducted to biochemically explain the decreased lipid deposition and increased protein accretion observed in pigs fed carnitine. Our hypothesis was that an increase in the ratio of acetyl CoA:CoA-SH produced by stimulation of fatty acid oxidation by supplemental L-carnitine may decrease branched-chain alpha-keto acid dehydrogenase activity and increase pyruvate carboxylase activity. Such changes could reduce oxidative loss of branched-chain amino acids and provide more carbons for amino acid biosynthesis. Yorkshire gilts (n = 36; 12 per treatment) were fed a control diet or diets containing either 50 or 125 ppm of added L-carnitine during growth from 56 to 120 kg. After slaughter, the semitendinosus muscle and liver were collected for isolation of mitochondria and hepatocytes. Increasing dietary L-carnitine did not influence growth performance (P > 0.10) but linearly decreased (P < 0.05) 10th rib backfat thickness and increased (linear, P < 0.05) percentages of lean and muscle. The rates of [1-(14)G]palmitate oxidation in isolated hepatocytes and isolated mitochondria, and incorporation of [35S]methionine into the acid insoluble fraction of isolated hepatocytes were increased (linear, P < 0.01) in pigs fed L-carnitine. Flux through branched-chain alpha-keto acid dehydrogenase linearly decreased (P < 0.01) in isolated liver and muscle mitochondria with increasing dietary carnitine. Flux through pyruvate carboxylase was increased (linear, P < 0.01) in isolated mitochondria from liver of pigs fed carnitine, and assays with particle-free extracts indicated that the amount of mitochondrial pyruvate carboxylase was tripled by feeding carnitine (linear, P < 0.01). The association of increased protein accretion and reduced backfat thickness with greater rates of palmitate oxidation, more rapid flux through pyruvate carboxylase, and reduced flux through branched-chain alpha-keto acid dehydrogenase suggests pigs fed carnitine are more able to use fat for energy, divert carbon toward synthesis of amino acids, and spare branched-chain amino acids for protein synthesis.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗
PubMed2001

Apparent ileal digestibility of amino acids and the digestible and metabolizable energy content of dry extruded-expelled soybean meal and its effects on growth performance of pigs.

We conducted three experiments to determine the apparent ileal digestibility of amino acids (Exp. 1), metabolizable and digestible energy (Exp. 2), and feeding value (Exp. 3) of dry extruded-expelled soybean meal with (DEH) or without (DENH) hulls compared with solvent-extracted soybean meal with hulls removed (SBMNH). Soybeans used to produce DEH were unadulterated prior to extrusion, but those used for DENH were dehulled prior to extrusion. In Exp. 1, six nonlittermate barrows (initially 39 kg) were fitted with ileal T-cannulas and used in a replicated 3 x 3 Latin square design digestion trial. Experimental diets (0.80% total lysine) were cornstarch-based and contained soybean meal from one of the three different sources as the sole source of lysine. Apparent ileal digestibilies of nutrients were similar (P > 0.10) for DEH and DENH. Apparent ileal digestibilies of CP, Lys, Ile, Leu, Arg, Phe, and Val were greater (P < 0.05) for DEH and DENH than for SBMNH. In Exp. 2, six barrows (initially 41 kg) were fed three corn-based diets containing 25% of one of the three soybean meal sources. A fourth diet was fed at the end of the trial containing all ingredients except soybean meal, so that energy values of the soybean meal could be determined by difference. Digestible energy and ME contents were similar (P > 0.10) for DEH and DENH and both had greater (P < 0.05) DE and ME contents than SBMNH. In Exp. 3, pigs (n = 216, initially 10.6 +/- 1.3 kg and 35 +/- 3 d of age) were blocked by weight and allotted to six dietary treatments. Corn-soybean meal-based diets (0.95% digestible lysine and 3.44 kcal/g ME) containing DEH or DENH were compared with similar diets containing SBMNH or solvent-extracted soybean meal with hulls (SBMH). In addition, a diet containing a second expelled soybean meal with hulls (ESBM) was compared with a diet containing SBMH and soy oil. Growth performance of pigs fed diets containing DEH or DENH was not different (P > 0.10) than that of pigs fed corresponding diets containing SMBH or SBMNH. Pigs fed ESBM had lower (P < 0.05) ADG and G/F compared with its corresponding SBMH and soy oil diet. In conclusion, DEH and DENH are more digestible than conventional soybean meal and can be successfully used in swine diets.

Amino Acids↗
PubMed2001

Effects of choice white grease or poultry fat on growth performance, carcass leanness, and meat quality characteristics of growing-finishing pigs.

Eighty-four crossbred gilts were used to evaluate the effects of dietary choice white grease (CWG) or poultry fat (PF) on growth performance, carcass characteristics, and quality characteristics of longissimus muscle (LM), belly, and bacon of growing-finishing pigs. Pigs (initially 60 kg) were fed a control diet with no added fat or diets containing 2, 4, or 6% CWG or PF. Diets were fed from 60 to 110 kg and contained 2.26 g lysine/Mcal ME. Data were analyzed as a 2 x 3 factorial plus a control with main effects of fat source (CWG and PF) and fat level (2, 4, and 6%). Pigs fed the control diet, 2% fat, and 4% fat had greater (P < 0.05) ADFI than pigs fed 6% fat. Pigs fed 6% fat had greater (P < 0.05) gain/feed (G/F) than pigs fed the control diet or other fat levels. Subcutaneous fat over the longissimus muscle from pigs fed CWG had more (P < 0.05) moisture than that from pigs fed PF. Feeding dietary fat (regardless of source or level) reduced (P < 0.05) the amount of saturated fats present in the LM. Similarly, 4 or 6% fat decreased (P < 0.05) the amount of saturated fats and increased unsaturated fats present in the bacon. No differences (P > 0.05) were observed for ADG, dressing percentage, leaf fat weight, LM pH, backfat depth, LM area, percentage lean, LM visual evaluation, LM waterholding capacity, Warner-Bratzler shear and sensory evaluation of the LM and bacon, fat color and firmness measurements, or bacon processing characteristics. Adding dietary fat improved G/F and altered the fatty acid profiles of the LM and bacon, but differences in growth rate, carcass characteristics, and quality and sensory characteristics of the LM and bacon were minimal. Dietary additions of up to 6% CWG or PF can be made with little effect on quality of pork LM, belly, or bacon.

Adipose Tissue↗
PubMed2001

Effect of dietary L-carnitine on growth performance and body composition in nursery and growing-finishing pigs.

Two experiments were conducted to determine the effect of dietary L-carnitine on growth performance and carcass composition of nursery and growing-finishing pigs. In Exp. 1,216 weanling pigs (initially 4.9 kg and 19 to 23 d of age) were used in a 35-d growth trial. Pigs were blocked by weight in a randomized complete block design (six pigs per pen and six pens per treatment). Four barrows and four gilts were used to determine initial carcass composition. L-Carnitine replaced ground corn in the control diets to provide 250, 500, 750, 1,000, or 1,250 ppm. On d 35, three barrows and three gilts per treatment (one pig/block) were killed to provide carcass compositions. L-Carnitine had no effect (P > 0.10) on growth, percentages of carcass CP and lipid, or daily protein accretion. However, daily lipid accretion tended to decrease and then return to values similar to those for control pigs (quadratic P < 0.10) with increasing dietary L-carnitine. In Exp. 2, 96 crossbred pigs (initially 34.0 kg BW) were used to investigate the effect of increasing dietary L-carnitine in growing-finishing pigs. Pigs (48 barrows and 48 gilts) were blocked by weight and sex in a randomized complete block design (two pigs/pen and eight pens/treatment). Dietary L-carnitine replaced cornstarch in the control diet to provide 25, 50, 75, 100, and 125 ppm in grower (34 to 56.7 kg; 1.0% lysine) and finisher (56.7 to 103 kg; 0.80% lysine) diets. At 103 kg, one pig/pen was slaughtered, and standard carcass measurements were obtained. Dietary L-carnitine did not influence growth performance (P > 0.10). However, increasing dietary carnitine decreased average and tenth-rib back-fat (quadratic, P < 0.10 and 0.05), and increased percentage lean and daily CP accretion rate (quadratic, P < 0.05). Break point analysis projected the optimal dosage to be between 49 and 64 ppm of L-carnitine for these carcass traits. It is concluded that dietary carnitine fed during the nursery or growing-finishing phase had no effect on growth performance; however, feeding 49 to 64 ppm of L-carnitine during the growing-finishing phase increased CP accretion and decreased tenth-rib backfat.

Animals↗
PubMed2000

Effects of pelleting and pellet conditioning temperatures on weanling pig performance.

We conducted two experiments to study the effects of pelleting and pellet conditioning temperature on weanling pig performance. In Exp. 1, 252 weanling pigs (PIC, L326 x C22) averaging 6.0 +/- 1.3 kg and 21 +/- 3 d of age were used to evaluate six corn-soybean meal-based diets containing 15% dried whey and formulated to contain 1.4% lysine. Treatments consisted of a control diet without spray-dried animal protein (SDAP) fed in meal form, a diet with 5% SDAP fed in meal form, and four diets with 5% SDAP that were conditioned at 60, 66, 71, or 77 degrees C for 10 s prior to pelleting. Pellets had a 3.97-mm diameter. The experimental diets were fed from d 0 to 14 after weaning, and all pigs were fed a common diet in meal form from d 14 to 28 after weaning. From d 0 to 7 after weaning, pigs fed diets containing SDAP had greater ADG, gain/feed (P < 0.001), and ADFI (P < 0.05) than pigs fed the control diet. No differences (P > 0.10) were observed between pigs fed the pelleted diets and those fed the SDAP diet in meal form. Conditioning temperature had no effect (P > 0.10) on weanling pig performance from d 0 to 14, and the diet fed from d 0 to 14 had no effect on overall performance (d 0 to 28). In Exp. 2, 252 weanling pigs (6.3 +/- 1.5 kg and 22 +/- 4 d of age) were used to evaluate diets with same composition as in Exp. 1, but treatments consisted of diets with or without SDAP conditioned at 60 degrees C before pelleting, and four diets containing 5% SDAP that were conditioned at 68, 77, 85, and 93 degrees C before pelleting. As in Exp. 1, conditioning lasted 10 s, pellets were 3.97 in mm diameter, and experimental diets were fed for the first 14 d of the 28-d experiment. From d 0 to 7, pigs fed the SDAP diet conditioned at 60 degrees C had greater ADFI (P < 0.05) and tended (P = 0.12) to have greater ADG than pigs fed the diet without SDAP and conditioned at 60 degrees C. From d 0 to 7, ADG (quadratic effect, P < 0.03) and ADFI (linear effect, P < 0.002) decreased as conditioning temperature increased, with the largest decrease observed above 77 degrees C. From d 0 to 14 and 0 to 28, ADG was not affected (P > 0.10) by pellet conditioning temperature or SDAP fed from d 0 to 14. The results of these studies suggest that conditioning diets containing 5% SDAP at temperatures above 77 degrees C decreases weanling pig growth performance.

Animal Feed↗
PubMed2000

Added dietary pyridoxine, but not thiamin, improves weanling pig growth performance.

We conducted two trials to determine the effects of added dietary pyridoxine (vitamin B6) or thiamin (vitamin B1) on growth performance of weanling pigs. In Exp. 1, weanling pigs (n = 180, initially 5.55 +/- .84 kg, and 21 +/- 2 d of age) were fed either a control diet (no added pyridoxine or thiamin) or the control diet with added thiamin (2.8 or 5.5 mg/kg) from thiamin mononitrate or pyridoxine (3.9 or 7.7 mg/kg) from pyridoxine HC1. These five diets were fed in meal form in two phases (d0 to 14 and 14 to 35 after weaning), with identical vitamin concentrations in both phases. From d 0 to 14 after weaning, pigs fed added pyridoxine had increased (quadratic, P < .05) ADG and ADFI; pigs fed 3.9 mg/kg of added pyridoxine had the greatest improvement. From d 14 to 35 and 0 to 35, ADG and ADFI increased (linear P = .06) for pigs fed increasing pyridoxine. Growth performance was not improved by added thiamin. In Exp. 2, weanling pigs (n = 216, initially 6.08 +/- 1.13 kg, and 21 +/- 2 d of age) were fed a control diet or the control diet with 1.1, 2.2, 3.3, 4.4, or 5.5 mg/kg of added pyridoxine from pyridoxine HCl. From d 0 to 14 after weaning, increasing pyridoxine increased (quadratic, P < .05) ADG and ADFI; pigs fed 3.3 mg/kg of added pyridoxine had the greatest ADG and ADFI. Break-point analysis suggested a requirement estimate of 3.3 and 3.0 mg/kg of added pyridoxine to maximize ADG and ADFI, respectively. From d 14 to 35 or 0 to 35, increasing pyridoxine had no effect (P > .10) on pig growth performance. These results suggest that adding 3.3 mg/kg of pyridoxine (7.1 to 7.9 mg/kg of total pyridoxine) to diets fed from d 0 to 14 after weaning can improve pig growth performance.

Animal Feed↗
PubMed2000

Effects of a whey protein product and spray-dried animal plasma on growth performance of weanling pigs.

Five experiments were conducted to evaluate the effects of a high-protein, whey protein product (WPP; 73% CP, 6.8% lysine, 12.8% fat, and 5% lactose) and spray-dried animal plasma (SDAP) on growth performance of weanling pigs. In all experiments, pigs were fed experimental diets from d 0 to 14 after weaning in a pelleted form and then a common diet in meal form for the remainder of the experiment. Dietary treatments were established by substituting WPP or SDAP for dried skim milk (Exp. 1) or soybean meal (Exp. 2, 3, 4, and 5) in the control diet. In Exp. 1, we maintained a constant level of lactose in all diets by adjusting the amount of added crystalline lactose. The amount of lactose in diets used in Exp. 2 through 5 varied slightly by the addition of WPP. In Exp. 1 and 2, 180 weanling pigs (initially 5.8 kg and 19 +/- 1 d of age or 5.5 kg and 17 +/- 1 d of age, respectively) were used. Treatment diets contained SDAP (2.5 and 5%) or WPP (2.7 and 5.4% in Exp.1, and 2.5 or 5.0% in Exp. 2). In Exp. 1, from d 0 to 7 after weaning, ADG and ADFI increased with increasing SDAP (linear, P < .01). No other treatment effects were observed during the d 0 to 14 period. In Exp. 2, from d 0 to 14 after weaning, ADG and G:F increased (linear, P < .04) with increasing SDAP or WWP. In Exp. 3, 305 weanling pigs (initially 4.1 kg and 12 +/- 1 d of age) were used. The control diet contained 2.5% SDAP. The experimental diets were similar to the control diet but contained an additional 2.5 or 5.0% SDAP or 2.5 or 5.0% WPP. From d 0 to 14 after weaning, ADG, ADFI, and G:F increased (quadratic, P < .05) with increasing SDAP up to 5.0%. Increasing WPP increased ADG (quadratic, P < .07) and ADFI (linear, P < .09). In Exp. 4 and 5, 329 and 756 weanling pigs (initially 4.1 kg and 12 +/- 1 d of age and 5.2 kg and 18 +/- 1 d of age, respectively) were fed diets in which WPP was substituted for 0, 25, 50, 75, and 100% (Exp. 4) or 0, 50, and 100% (Exp. 5) of the SDAP in the control diet. In Exp. 4 and 5, from d 0 to 14 after weaning, pigs fed a 1:1 blend of each protein source had better ADG (quadratic, P < .04) than those only fed SDAP. In conclusion, WPP can be used in combination with or as a total replacement for SDAP in diets for weanling pigs without reducing performance.

Animal Feed↗
PubMed2000

The effects of branched-chain amino acids on sow and litter performance.

Sows (n = 306; PIC, Line C-19; average parity 2.1) were used to evaluate the interrelationship between valine, isoleucine, and leucine on sow and litter performance. Our objective was to determine whether the increase in litter weaning weight associated with added dietary valine is specific for valine or a result of the total branched-chain amino acid (i.e., isoleucine and[or] leucine) concentration of the diet. Eight dietary treatments (36 to 41 sows/treatment) were arranged as a 2 x 2 x 2 factorial with two levels of valine (.80 and 1.20%), isoleucine (.68 and 1.08%), and leucine (1.57 and 1.97%). This provided total branched-chain amino acid levels of 3.05, 3.45, 3.85, and 4.25%. The lowest level of each branched-chain amino acid was similar to that in a .90% lysine corn-soybean meal diet containing .15% L-lysine HCl. Amino acids other than valine, isoleucine, and leucine met or exceeded their suggested estimates relative to lysine using ratios derived from the National and Agricultural Research Councils. Average number of pigs on d 2 of lactation was 11.2, and average lactation length was 20.9 d. Number of pigs weaned (x = 10.6), sow ADFI (x = 5.85 kg), and sow weight loss (x = 4.25 kg) were not affected by dietary treatment (P > .10). Sow backfat loss (P < .02), litter weaning weight (P < .04), and litter weight gain from d 2 to weaning (P > .05) increased as dietary valine increased. Litter weight at weaning and litter weight gain were not affected by dietary isoleucine (P > .80) or leucine (P > .60). Sixteen or 17 sows per treatment (129 total) were milked manually on d 14 to 16 of lactation. Increasing dietary valine tended to increase milk urea N (P < .07) but did not affect milk DM, CP, fat, lactose, or ash. Increasing dietary isoleucine or leucine had no effects on milk composition. These results confirm the importance of dietary valine for increased litter weaning weight, independent of either additional dietary leucine or isoleucine.

Amino Acids, Branched-Chain↗