• 제목/요약/키워드: Nursery Diet

검색결과 55건 처리시간 0.02초

Roasting and Extruding Affect Nutrient Utilization from Soybeans in 5 and 10 kg Nursery Pigs

  • Kim, I.H.;Hancock, J.D.;Hines, R.H.;Gugle, T.L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권2호
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    • pp.200-206
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    • 2000
  • Ninety nursery pigs were used in two metabolism experiments to determine the effects of roasting and extruding on the nutritional value of Williams 82 soybeans with (+K) and without (-K) gene expression for the Kunitz trypsin inhibitor. Treatments for both experiments were: 1) soybean meal; 2) +K roasted; 3) +K extruded; 4) -K roasted; and 5) -K extruded. Diets were the soybean preparations (96.5% of the diet) with only vitamins and minerals added as needed to meet or exceed NRC recommendations. Daily feed allowance was 5% of initial BW given as three equal meals. In Exp. 1, 50 weanling pigs (4.7 kg average BW and 21 d average age) were used. Apparent values for N digestibility (p<0.001), biological value (p<0.09), percentage N retention (p<0.05), GE digestibility (p<0.001) and percentage ME (p<0.001) were greater for pigs fed extruded soybeans than pigs fed roasted soybeans. Also, N digestibility (p<0.05), biological value (p<0.03) and percentage N retention (p<0.04) were greater for pigs fed -K soybeans than those fed +K soybeans. In Exp. 2, 40 pigs (9.7 kg average BW and 35 d average age) were allowed to adjust to the nursery environment before use in the experiment. In general, the pigs in Exp. 2 (i.e., the older pigs) had greater utilization of nutrients from all of the soybean products than the younger pigs used in Exp. 1. Digestibilities of DM, N and GE were greater (p<0.001) for pigs fed -K soybeans than those fed +K soybeans and extruded soybeans had greater digestibilities of DM, N and GE than roasted soybeans (p<0.001). Also, percentage N retention (p<0.01) and percentage ME (p<0.001) for pigs fed extruded soybeans were greater than for pigs fed roasted soybeans. In conclusion, extruded and -K soybeans were greater nutritional value than roasted and +K soybeans for 4.7 and 9.7 kg nursery pigs.

Effects of Replacing Dried Skim Milk With Wheat Gluten and Spray Dried Porcine Protein on Growth Performance and Digestibility of Nutrients in Nursery Pigs

  • Burnham, L.L.;Kim, I.H.;Hancock, J.D.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권11호
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    • pp.1576-1583
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    • 2000
  • Three experiments were conducted to determine the nutritional value of wheat gluten (WG) and spray-dried porcine plasma (SDPP) in diets for nursery pigs. In Exp. 1, 120 weanling pigs (5.7 kg avg initial BW) were used in a 35-d growth assay. Treatments for d 0 to 14 were: 1) dried skim milk (DSM)-dried whey-SBM based control; 2) WG to replace the protein from DSM; 3) SDPP; and 4) WG-SDPP (50:50 blend on a protein basis) to replace the protein from DSM. From d 14 to 35, all pigs were fed a common corn-SBM-whey-based diet. For d 0 to 14, there were no differences in ADG, ADFI, and gain/feed (p>0.11). However, for d 14 to 35, pigs fed diets with WG had greater gain/feed than those fed SDPP (p<0.05), and pigs fed diets with the WG-SDPP blend had greater ADG than pigs fed diets with WG or SDPP alone (p<0.07). In a second experiment, 60 weanling pigs (5.1 kg avg initial BW) were used in a 28-d growth assay. All pigs were fed the WG-SDPP diet fed in Exp. 1 for d 0 to 14, and changed to experimental diets for d 14 to 28. Treatments were: 1) the whey-SBM-based diet used for d 14 to 28 in Exp. 1; or 2) a whey-SBM based diet with 3% added SDPP. There were no differences in ADG, ADFI, gain/feed, or apparent digestibilities of DM and N among treatments for d 14 to 28 or overall (p>0.14). In a third experiment, 150 weanling pigs (5.6 kg avg initial BW) were used in a 32-d growth assay to determine the optimal blend of WG and SDPP for use after weaning. The SDPP was added as 8% of the control diet, and WG was substituted on a protein basis to yield the desired SDPP:WG blends. Treatments were (d 0 to 14): 1) SDPP; 2) 75% SDPP and 25% WG; 3) 50% SDPP and 50% WG; 4) 25% SDPP and 75% WG; and 5) WG. As in Exp. 1, all pigs were switched to a common corn-SBM-whey-based diet for d 14 to 32. For d 0 to 14, ADG and ADFI increased as replacement of the SDPP was increased up to 50% and decreased when more of the SDPP was removed from the diet (quadratic effects, p<0.004 and 0.02, respectively). Apparent digestibilities of DM and N (at d 13) were not affected by treatments (p>0.18). For d 14 to 32, treatments did not affect ADG (p>0.2), although there were quadratic responses in ADFI (p<0.04), with pigs fed the 50:50 blend suggested the greatest intake of feed. For the overall experimental period (d 0 to 32), ADG, ADFI, and gain/feed increased as WG was used to replace as much as 50% of the SDPP (quadratic effects p<0.04, 0.02, and 0.06, respectively). In conclusion, WG can successfully replace up to 50% of the SDPP in a complex nursery diet, when SDPP is included at the 8% level. There is no advantage to keeping SDPP in the diet after Phase I (d 0 to 14).

자돈 및 육성돈에 있어 α-1,6-galactosidase와 β-1,4-mannanase의 사료내 첨가가 성장 및 영양소 소화율에 미치는 영향 (Effect of Dietary α-1,6-Galactosidase and β-1,4-Mannanase on Growth Performance and Nutrient Digestibility in Nursery and Growing Pigs)

  • 권오석;김인호;이상환;홍종욱;김지훈;문태현;이지훈
    • Journal of Animal Science and Technology
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    • 제45권2호
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    • pp.211-218
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    • 2003
  • 본 연구는 양돈사료내 대두박 항영양인자인 $\alpha$-galactosides와 galatomannan의 분해를 유도하는 $\alpha$-1,6-galactosidase와 $\beta$-1,4-mannanase의 사료내 첨가가 자돈 및 육성돈의 성장과 영양소 소화율에 미치는 영향을 조사하기 위하여 실시하였다. 시험 1은 개시시 체중 10.57$\pm$0.30kg의 3원 교잡종 자돈 60두를 공시하였으며, 시험설계는 옥수수-건조유청-대두박 위주의 사료에 NRC (1998)의 영양소 요구량에 따라 처리한 대조구 (CON), 대조구 사료내 복합효소제를 0.1% 첨가한 처리구로 하였다. 사양시험기간동안, 일당증체량에 있어서는 대조구와 비교하여 EC0.1 처리구가 높은 것으로 평가되었으나 유의적인 차이는 보이지 않았다. 그러나 사료효율에 있어서는 대조구와 비교하여 EC0.1 처리구가 유의적으로 높게 평가되었다 (P<0.05). 건물과 질소 소화율에 있어서 대조구와 비교하여 처리구가 향상된 것으로 조사되었다 (P<0.05). 시험 2는 개시시 체중 22.30$\pm$0.45kg의 3원 교잡종 육성돈 36두를 공시하였으며, 시험설계는 옥수수-대두박 위주의 사료에 NRC (1998)의 영양소 요구량에 따라 처리한 대조구 (AME, adequate ME diet), 대조구 사료내 복합효소제를 0.1% 첨가한 처리구 (AME+EC0.1, Adequate ME diet+ 0.1% 복합효소제), 대조구 사료에서 대사에너지 함량을 4% 낮춘 사료에 복합효소제를 0.1% 첨가한 처리구 (LME+EC0.1, Low ME diet + 0.1% 복합효소제)로 하였다. 총 30일간의 사양시험 기간동안, 일당증체량에 있어서는 AME 처리구와 비교하여 복합효소제 처리구가 유의적인 성장율이 높은 것으로 조사되었다 (P<0.05). 건물 및 질소 소화율에 있어서는 AME 처리구와 비교하여 복합효소제 첨가구가 유의적으로 높게 평가되었다 (P<0.05). 결론적으로, 자돈 및 육성돈 사료에 복합효소제의 첨가는 성장능력 및 영양소 소화율을 향상시키는 것으로 사료된다.

Saccharomyces yeast postbiotics supplemented in feeds for sows and growing pigs for its impact on growth performance of offspring and growing pigs in commercial farm environments

  • Sung Woo Kim;Marcos Elias Duarte
    • Animal Bioscience
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    • 제37권8호
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    • pp.1463-1473
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    • 2024
  • Objective: Three experiments were conducted to evaluate the effects of Saccharomyces yeast postbiotics (SYP) in feeds for sows on the growth of offspring (Exp. 1), for nursery pigs on their growth (Exp. 2), and for nursery and finishing pigs on their growth (Exp. 3). Methods: Exp. 1 had 80 sows at breeding assigned to 4 groups with SYP at 0, 0.050, 0.175, and 0.500 g/kg. Offspring were fed a common diet for 126 d. Exp. 2 had 144 barrows at 8 kg body weight (BW) allotted to CON (no SYP); YPC (SYP at 0.175 g/kg; d 0 to 42); and YPD (SYP at 1.25, 0.75, and 0 g/kg; d 0 to 7, d 8 to 21, and d 22 to 42, respectively) with 8 pens/treatment (6 pigs/pen). Exp. 3 had 96 barrows at 8 kg BW allotted to CON (no SYP); YPN (SYP at 0.175 g/kg; d 0 to 42); YPF (SYP at 0.100 g/kg; d 43 to 119); and YPA (SYP at 0.175 and 0.100 g/kg; d 0 to 42 and d 43 to 119, respectively) with 8 pens/treatment (3 pigs/pen). Results: In Exp. 1, increasing SYP increased (p<0.05, quadratic) the sow body score (maximum at 0.30% SYP), reduced (p<0.05, quadratic) the days-wean-to-estrus (minimum at 0.27% SYP), and increased (p<0.05) offspring BW at weaning and their average daily gain (ADG) and feed efficiency (G:F) at d 126. In Exp. 2, ADG, average daily feed intake (ADFI), and G:F of YPC were the greatest (p<0.05). The ADG and ADFI of YPD were greater (p<0.05) than CON. Fecal score of YPC and YPD was smaller (p<0.05) than CON. In Exp. 3, YPA had the greatest (p<0.05) ADG and YPN and YPF had greater (p<0.05) ADG than CON. Conclusion: SYP enhanced sow performance, offspring growth, growth of nursery and growing pigs with the greater efficacy at 0.27 to 0.32 g/kg feed.

Processing Effects of Feeds in Swine - Review -

  • Chae, B.J.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제11권5호
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    • pp.597-607
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    • 1998
  • Processing is generally employed to alter the physical and chemical properties of feeds used in pig diets, using hammer/roller mills, pellet mills and extruders/expanders. The reported optimum particle sizes of corn are approximately $500{\mu}m$, $500-700{\mu}m$, $400-600{\mu}m$, for nursery, growing-finishing, and breeder pigs respectively. Optimum particle size of grains are affected by diet complexity. There was a trend towards reducing particle size in order to increase ADG in pigs fed a simple diet, though such was not the case for pigs fed a complex diet. Uniformity of particle size also affects the nutritional values of swine feeds. Uniform particle sizes would consistently give greater nutrient digestibilities. In terms of pellet quality, it is reported that a higher incidence of fmes in pelleted feeds has a direct correlation with poorer feed conversion ratio in pigs. Particle and pellet sizes are also very important for pelleting in terms of grinding, digestibility, stomach ulceration and pellet durability. A particle size of $600{\mu}m$, or slightly less, seemed optimal for com in fmishing pigs, and the 5/32 in. diameter pellets supported the best efficiencies of gain during nursery and finishing phases. Extruder and/or expander processes would allow the feed industry an increased flexibility to utilize a wider spectrum of feed ingredients, and improve pellet quality of finished feeds. It would appear that extruded or expanded diets containing highly digestible ingredients have little effect on the growth performance of pigs, and the feeding values of the feeds over pelleted diets were not improved as pigs grew. The extruder or expander is much more effective than a pelletizer in salmonella control. Gastric ulcerations and/or keratinizations were consistently reported in pigs fed mash and processed diets containing finely ground grains, whereas carcass quality was not affected by diet processing methods such as pelleting, extruding or expanding. In corn- or sorghum-based diets, the electrical energy consumption is 4-5 times higher in the expanding than in the pelleting process. But the expander's processing cost was half of that shown by an extruder. Finally, the decision of which feed processing technology to adopt would depend on the processing cost, and any potential improvement in growth performance and digestibilities of nutrients should offset the increased operating and capital costs related to the extruder/expander technology over mash or pelleting processes in pigs.

Energy and Ileal Digestible Amino Acid Concentrations for Growing Pigs and Performance of Weanling Pigs Fed Fermented or Conventional Soybean Meal

  • Wang, Y.;Lu, W.Q.;Li, D.F.;Liu, X.T.;Wang, H.L.;Niu, S.;Piao, X.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권5호
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    • pp.706-716
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    • 2014
  • A new strategy of co-inoculating Bacillus subtilis MA139 with Streptococcus thermophilus and Saccharomyces cerevisiae was used to produce fermented soybean meal (FSBM). Three experiments were conducted to determine the concentration of digestible energy (DE) and metabolizable energy (ME) (Exp. 1), apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) (Exp. 2), and feeding value (Exp. 3) of FSBM produced by this new strategy (NFSB) compared with soybean meal (SBM) and conventionally available FSBM (Suprotein). In Exp. 1, twenty-four barrows (initial body weight [BW] of $32.2{\pm}1.7kg$) were randomly allotted to 1 of 4 diets with 6 replicates per diet. A corn basal diet and 3 diets based on a mixture of corn and 1 of 3 soybean products listed above were formulated and the DE and ME contents were determined by the difference method. The results showed that there were no differences in DE and ME between SBM and either FSBM product (p>0.05). In Exp. 2, eight barrows (initial BW of $26.8{\pm}1.5kg$) were fitted with ileal T-cannulaes and used in a replicated $4{\times}4$ Latin square design. Three corn-starch-based diets were formulated using each of the 3 soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. The results showed that the SID of all AA except arginine and histidine was similar for NFSB and SBM (p>0.05), but Suprotein had greater (p<0.05) SID of most AA except lysine, aspartate, glycine and proline than NFSB. In Exp. 3, a total of 144 piglets (initial BW of $8.8{\pm}1.2$ kg) were blocked by weight and fed 1 of 4 diets including a control diet with 24% SBM as well as diets containing 6% and 12% NFSB or 12% Suprotein added at the expense of SBM. During d 15 to 28, replacing SBM with 6% NFSB significantly improved average daily gain (ADG) and average daily feed intake (ADFI) (p<0.05) for nursery piglets. During the overall experiment, ADG of piglets fed diets containing 6% NFSB was significantly greater (p<0.05) than that of piglets fed SBM. In conclusion, fermentation with the new strategy did not affect the energy content or the AID and the SID of AA in SBM. However, inclusion of 6% NFSB in diets fed to nursery piglets improved performance after weaning likely as a result of better nutritional status and reduced immunological challenge.

Use of δ-Aminolevulinic Acid in Swine Diet: Effect on Growth Performance, Behavioral Characteristics and Hematological/Immune Status in Nursery Pigs

  • Mateo, R.D.;Morrow, J.L.;Dailey, J.W.;Ji, F.;Kim, Sung Woo
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권1호
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    • pp.97-101
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    • 2006
  • Certain amino acids are essential precursors of a variety of important biomolecules in addition to their major function as protein building blocks. ${\delta}$-Aminolevulinic acid (ALA) is synthesized from the condensed form of succinyl-CoA with glycine after decarboxylation catalyzed by ALA synthase. The objective of the study was to determine the effects of ALA supplementation on growth performance, behavioral characteristics and hematological/immune status in nursery pigs. A total of 144 pigs weaned at 21 d of age were allotted to three dietary treatments representing (-) control (w/o antibiotics; NC), (+) control (w/carbadox at 50 mg/kg; PC), and the treatment group with ALA supplementation (0.05%; TA). Each treatment had 6 pens (replicates) with 8 pigs per pen. Pigs were fed phase 1 (21.9% CP, 1.40% Lys) and 2 (20.6% CP, 1.15% Lys) experimental diets for 3 and 2 wks, respectively. Feed intake and weight gain were measured weekly during phase 1 and at the end of phase 2. At the end of phase 2, blood samples were taken and analyzed using an automated hematology analyzer. Skin color and activity of pigs (48 h) from all pens in each treatment were measured at the second week of phase 2. Growth performance was not affected (p>0.05) by the dietary supplementation of ALA during the 5 wk nursery period. Pigs in the TA (6.46) and PC (6.68) had a higher (p<0.05) number of red blood cells ($10^6cell/{\mu}L$) than pigs in the NC (6.15). Pigs in PC (12.16) had a higher (p<0.05) hemoglobin level (g/dL) than pigs in the NC group (11.29) and the TA group (11.47). Pigs in the TA and PC had darker (p<0.05) and less (p<0.05) yellow skin color than pigs in the NC. Pigs in the PC tended (p = 0.081) to be less active than pigs in the other groups. There were no differences in behavioral characteristics between the NC and the TA. The data suggest that ALA supplementation has no adverse effects on growth performance of nursery pigs. Moreover, ALA supplementation increased red blood cell counts which may be beneficial to pigs.

Emissions of Odor, Ammonia, Hydrogen Sulfide, and Volatile Organic Compounds from Shallow-Pit Pig Nursery Rooms

  • Kafle, Gopi Krishna;Chen, Lide
    • Journal of Biosystems Engineering
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    • 제39권2호
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    • pp.76-86
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    • 2014
  • Purpose: The objective of this study was to measure emissions of gases (ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and carbon dioxide ($CO_2$)), volatile organic compounds (VOC) and odor from two shallow pit pig nursery rooms. Gas and odor reduction practices for swine operations based on the literature were also discussed. Methods: This study was conducted for 60 days at a commercial swine nursery facility which consisted of four identical rooms with mechanical ventilations. Two rooms (room 1 (R1) and room 2 (R2)) with different pig numbers and ventilation rates were used in this study. The pig manure from both the R1 and R2 were characterized. Indoor/outdoor temperatures, ventilation rates/duration, $NH_3$, $H_2S$, $CO_2$, and VOC concentrations of the ventilation air were measured periodically (3-5 times/week). Odor concentrations of the ventilations were measured two times on two days. Three different types of gas and odor reduction practices (diet control, chemical method, and biological method) were discussed in this study. Results: The volatile solids to total solids ratio (VS/TS) and crude protein (CP) value of pig manure indicated the pig manure had high potential for gas and odor emissions. The $NH_3$, $H_2S$, $CO_2$ and VOC concentrations were measured in the ranges of 1.0-13.3, 0.1-5.7, 1600-3000 and 0.0-1.83 ppm, respectively. The $NH_3$ concentrations were found significantly higher than $H_2S$ concentrations for both rooms. The odor concentrations were measured in the range of $2853-4432OU_E/m^3$. There was significant difference in odor concentrations between the two rooms which was due to difference in pig numbers and ventilation duration. The literature studies showed that simultaneous use of dietary control and biofiltration practices will be more effective and environmentally friendly for gas and odor reductions from pig barns. Conclusions: The gas and odor concentrations measured in the ventilation air from the pig rooms indicate an acute need for using gas and odor mitigation technologies. Adopting diet control and biofiltration practices simultaneously could be the best option for mitigating gas and odor emissions from pig barns.

Effects of Diet Complexity and Fermented Soy Protein on Growth Performance and Apparent Ileal Amino Acid Digestibility in Weanling Pigs

  • Ao, X.;Kim, H.J.;Meng, Q.W.;Yan, L.;Cho, J.H.;Kim, I.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권11호
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    • pp.1496-1502
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    • 2010
  • Two experiments were conducted to evaluate the effects of diet complexity and fermented soy protein on growth performance and amino acid digestibility. In Exp. 1, a total of 120 crossbred weanling pigs ($5.68{\pm}0.80\;kg$ BW) were randomly allocated into 4 treatments. Each treatment had 6 replicate pens comprising 5 pigs in each replicate. Experimental diets consisted of simple (soybean meal as protein source) and complex (soybean meal, rice protein concentrate, potato protein concentrate and fish meal as protein sources) diets; each diet contained 0 or 5% fermented soy protein (FSP), respectively. Dietary treatments included: i) simple diet; ii) simple diet with 5% FSP; iii) complex diet; iv) complex diet with 5% FSP. Pigs were provided each experimental diet for 20 d (phase 1) and then fed the same common diet for 10 d (phase 2). During days 0-10, pigs fed FSP diets had greater ADG than those fed non-FSP diets (p<0.05). G/F in FSP treatments was significantly higher than that in non-FSP treatments (p<0.05) from days 0 to 10. Throughout the overall period, G/F was greater in FSP treatments compared with non-FSP treatments (p<0.05). On d 10, N digestibility was higher in pigs fed FSP diets than in those fed non-FSP diets (p<0.05). Diet complexity did not affect growth performance and nutrient digestibility (p>0.05) in this experiment. In Exp 2, 12 ileal-cannulated, weanling barrows were housed in individual metabolism crates and randomly assigned to 1 of 4 treatments (same as Exp. 1) by using a $4{\times}4$ Latin square design. Among the essential amino acids, apparent ileal digestibility (AID) of Met and Val were increased in pigs fed FSP diets compared with those fed non-FSP diets (p<0.05). AID of Met, Phe and total essential amino acids were higher in pigs fed complex diets than in those fed simple diets (p<0.05). Among the non-essential amino acids, AID of Ala in FSP treatments was greater than that in non-FSP treatments (p<0.05). In addition, Asp, Cys, Glu, Pro, Ser and total non-essential amino acid digestibilities in pigs fed complex diets were higher compared with those fed simple diets (p<0.05). Interaction was observed in AID of Met, Asp and Pro. In conclusion, these results indicated that feeding of 5% FSP to nursery pigs improved feed efficiency and AID of amino acids, and diet complexity did not maximize the growth performance of pigs in the subsequent phase.

Effects of Antibiotics, Zinc Oxide or a Rare Earth Mineral-Yeast Product on Performance, Nutrient Digestibility and Serum Parameters in Weanling Pigs

  • Han, Yung-Keun;Thacker, Philip A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권8호
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    • pp.1057-1065
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    • 2010
  • Two experiments were conducted to compare the effects of feeding a newly-developed rare earth mineral-yeast product, zinc oxide (ZnO) or antibiotics on the performance, nutrient digestibility and serum parameters of weanling pigs. In experiment 1, 150 crossbred barrows (24 d old and 6.28 kg BW) were fed one of five dietary treatments consisting of an unsupplemented basal diet or the basal diet supplemented with antibiotics (33 ppm tiamulin and 100 ppm chlortetracycline), ZnO (1,500 or 2,500 ppm) or 0.1% peptide-bound rare earth mineral-yeast. In experiment 2, 576 crossbred barrows (28 d old and 7.20 kg BW) were fed the same diets as those used in experiment 1 modified only by the addition of 1.0% Celite 545 to all diets as a digestibility marker. However, the negative control was not included. In experiment 1, weight gain was significantly lower (p<0.05) for pigs fed the negative control than for pigs fed diets supplemented with antibiotics, ZnO, or rare earth mineral-yeast. Pig performance did not differ between pigs fed the four supplemented diets. In experiment 2, there were no differences in performance between pigs fed diets supplemented with antibiotic, ZnO or rare earth mineral-yeast. The digestibility of dry matter, crude protein, calcium, phosphorus and energy were significantly (p<0.01) higher on the rare earth mineral-yeast diet than on diets supplemented with ZnO. In addition, pigs fed the diet supplemented with rare earth mineral-yeast had significantly (p<0.05) higher digestibility of histidine, lysine, threonine and valine than pigs fed the ZnO supplemented diets. Digestibility coefficients for pigs fed antibiotics tended to be intermediate to those of pigs fed rare earth mineralyeast or ZnO. In conclusion, the performance of pigs fed rare earth mineral-yeast was basically equal to that of pigs fed antibiotics or ZnO indicating that rare earth mineral-yeast can be successfully used as a growth promoter in diets fed to nursery pigs. The effects of rare earth mineral-yeast appeared to be mediated through improvements in nutrient digestibility.