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We investigated whether dietary supplementation with Aurantiochytrium sp. meal, a DHA-rich source (docosahexaenoic acid, 22: 6 n-3), fed during long-term exposure to cold-suboptimal temperature (22 °C, P1), followed by short-term exposure to higher temperatures (28 °C, P2, and 33 °C, P3), would promote oxidative damage in Nile tilapia (Oreochromis niloticus). Two supplementation levels were tested: 1.0 g 100 g

Background Our previous study showed that 3 plant extracts enhanced the immune responses and growth efficiency of weaned pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV), which is one of the most economically important disease in swine industry. However, each plant extract differently effected on growth efficiency and immune responses. Therefore, the objective of this study was conducted to characterize the effects and investigate the potential underlying mechanisms of 3 plant extracts on gene expression of alveolar macrophages in weaned pigs experimentally infected with PRRSV. Results PRRSV infection altered (P P P P P P Conclusions The results suggest that 3 plant extracts differently regulated the expression of genes in alveolar macrophages of PRRSV-infected pigs, especially altering genes involved in immunity.

This study evaluated the inclusion of Aurantiochytrium sp. (ALL‐G‐RICH™), a source of docosahexaenoic acid (22:6 n‐3, DHA), in the diet of Nile tilapia and its effect on growth performance indexes and body composition. Fish (initial mean weight 8.35 ± 0.80 g) were fed different dietary inclusion levels of ALL‐G‐RICH™: 0.00, 0.05, 0.10, 0.20, and 0.40 g/kg and a control diet using cod liver oil (CLO), to provide DHA content comparable to the inclusion of 0.10 g/kg ALL‐G‐RICH™. Although there was no significant effect (p > 0.05) on weight gain, specific growth rate, feed conversion, protein retention rate, and proximal body composition, the inclusion of ALL‐G‐RICH™ in the Nile tilapia diet influenced positively the fatty acid profile in the body, resulting in a high DHA concentration. CLO‐fed fish accumulated significantly more DHA compared to those fed 0.10 g/kg ALL‐G‐RICH™ (p

Aurantiochytrium sp. is a heterotrophic microorganism that produces docosahexaenoic acid (DHA), thus being considered as a possible replacement for fish oil in aquafeeds. We investigated the effect of Aurantiochytrium sp. meal (AM) dietary levels (0, 5, 10, 20, and 40 g kg−1) on Nile tilapia body and hepatopancreas fatty acid (FA) profile, body FA retention, somatic indices, and morphophysiological changes in the intestine and hepatopancreas, after feeding Nile tilapia juveniles (average initial weight 8.47 g) for 87 days at 22 °C. The 10AM diet was compared to a control diet containing cod liver oil (CLO), since their DHA concentration was similar. Within fish fed diets containing increasing levels of AM, there was a linear increase in n-3 FA content, especially DHA, which varied in the body (0.02 to 0.41 g 100 g−1) and hepatopancreas (0.15 to 1.05 g 100 g−1). The morphology of the intestines and hepatopancreas was positively affected in AM-fed fish. Fish fed 10AM showed less accumulation of n-3 FAs in the body and hepatopancreas when compared to fish fed CLO. Therefore, AM is an adequate substitute for fish oil in winter diets for Nile tilapia, with the supplementation of 40AM promoting the best results regarding intestine and hepatopancreas morphophysiology.

The effect of increasing amounts (0%, 25%, 50%, 75%, and 100%) of dietary supplementation with an organic micromineral complex (Fe, Zn, Cu, Mn, and Se) on antioxidant defenses and mineral deposition in tissues of Nile tilapia juveniles was evaluated, where 100% supplementation represented the average adopted by the feed industry in Brazil. Fish (initial weight 23.93 ± 0.80 g) were fed until apparent satiation twice a day for 56 days. The maximum deposition of Fe and Zn in the hepatopancreas occurred in fish given approximately 50% supplementation, whereas the deposition of Mn and Se increased linearly with the inclusion of the complex. The activity of catalase and superoxide dismutase in the hepatopancreas decreased in fish fed the 50% dose, when compared to those not receiving mineral supplementation or those receiving higher doses. Glutathione peroxidase (GPx) activity in the hepatopancreas increased as the dietary Se concentration increased. However, the concentration of metallothionein in the hepatopancreas showed an inverse relationship to the increase in dietary supplementation of the organic mineral complex. There was no relationship between the doses of organic micromineral supplementation and the activities of GPx, reduced glutathione, non-protein thiols, or protein carbonylation. However, diets supplemented with 50% to 100% promoted greater GPx activity when compared to the 0% supplemented diet. Supplementation with intermediate doses of organic microminerals, approximately 50% of that used in commercial tilapia diets, promoted the homeostasis of metal metabolism, especially for Fe and Zn.

Grains grown in various regions of the United States vary in their innate or natural Se contents. A regional study evaluated the effects of adding inorganic Se (sodium selenite) or organic Se (Se yeast) to diets with differing innate Se contents. A 2 × 2 + 1 factorial experiment evaluating 2 Se sources (organic or inorganic) at 2 Se levels (0.15 or 0.30 mg/kg) in 18 total replicates (n = 360 total pigs). A basal diet was fed without supplemental Se and served as the negative (basal) control. The study was conducted as a randomized complete block design in 9 states (Georgia, Illinois, Kentucky, Nebraska, North Carolina, Ohio, South Dakota, Texas, and Wisconsin) with each station conducting 2 replicates. Pigs were fed from 25 to approximately 115 kg BW. Similar dietary formulations were used at each station, incorporating a common source of trace mineral and Se premixes. Three pigs per treatment in 16 replicates (n = 240) were bled at 55, 85, and 115 kg BW and serum Se and glutathione peroxidase (GSH-Px) activities were determined. Three pigs (n = 260) from each treatment pen were killed at 115 kg BW and issues (liver, loin, and hair) were analyzed for Se. The corn Se content from the various states ranged from 0.026 to 0.283 mg Se/kg while the soybean meal Se content ranged from 0.086 to 0.798 mg Se/kg. Tissue and serum Se concentrations were greater (P < 0.01) when supplemental organic Se was fed, whereas serum GSH-Px was greater (P < 0.01) as Se level increased. There were linear increases (P < 0.01) in loin and quadratic increases (P < 0.01) in liver and hair Se concentrations as dietary Se level increased within each state. There was a source × level interaction (P < 0.01) for each tissue resulting in a greater increase when organic Se was fed. Serum Se and GSH-Px activity increased (P < 0.01) when both Se sources were fed and plateaued at each state at 0.15 mg Se/kg. There was a high and significant correlation between each tissue Se, serum Se, and GSH-Px activity to dietary Se level indicating that those states having greater grain natural Se contents also had greater tissue Se concentrations. These results indicate that a large difference in corn and soybean meal Se concentrations exists between states, that the addition of organic or inorganic Se to these grains increased tissue and serum Se in each state, and that organic Se was incorporated at greater concentrations in the loin, liver, and hair tissues of grower-finisher pigs than inorganic Se.

BACKGROUND Conventional distillers dried grains with solubles (DDGS-CV), uncooked distillers dried grains with solubles (DDGS-BPX) and high-protein distillers dried grains (HP-DDG) are used in diets for pigs to provide protein and energy. These ingredients may have different effects on body composition and energy retention. Therefore, an experiment was conducted to determine effects of DDGS-CV, DDGS-BPX and HP-DDG on body composition and on retention of protein, lipids, and energy when fed to growing or finishing pigs. RESULTS The total organ weight was greater (P < 0.05) for finishing pigs fed the HP-DDG diet than for finishing pigs fed the basal diet or the DDGS-CV diet. Finishing pigs fed the DDGS-CV diet had greater (P < 0.05) lipid gain than pigs fed the other diets, and the net energy (NE) for DDGS-CV was greater (P < 0.05) than for DDGS-BPX, but the NE value of HP-DDG was not different from that of DDGS-CV or DDGS-BPX. CONCLUSION Inclusion of up to 30% DDGS or HP-DDG in diets fed to growing or finishing pigs will not affect body composition or the retention of energy, protein and lipids, regardless of the stage of growth of pigs. The NE value of DDGS-BPX and HP-DDG is not affected by the stage of growth of pigs, but the NE value of DDGS-CV is greater in finishing than in growing pigs. © 2014 Society of Chemical Industry

The objectives of this experiment were 1) to determine if dietary soybean oil (SBO) affects the NE of corn when fed to growing or finishing pigs, 2) to determine if possible effects of dietary SBO on the NE of corn differ between growing and finishing pigs, and 3) to determine effects of SBO on pig growth performance and retention of energy, protein, and lipids. Forty-eight growing (initial BW: 27.3 ± 2.5 kg) and 48 finishing (initial BW: 86.0 ± 3.0 kg) barrows were used, and within each stage of growth, pigs were allotted to 1 of 6 groups. Two groups at each stage of growth served as an initial slaughter group. The remaining 4 groups were randomly assigned to 4 dietary treatments and pigs in these groups were harvested at the conclusion of the experiment. A low-lipid basal diet containing corn, soybean meal, and no added SBO and a high-lipid basal diet containing corn, soybean meal, and 8% SBO were formulated at each stage of growth. Two additional diets at each stage of growth were formulated by mixing 25% corn and 75% of the low-lipid basal diet or 25% corn and 75% of the high-lipid basal diet. Results indicated that addition of SBO had no effects on growth performance, carcass composition, or retention of energy, protein, and lipids but increased (P < 0.05) apparent total tract digestibility of acid hydrolyzed ether extract and GE. Addition of SBO also increased (P < 0.05) DE and NE of diets, but had no effect on the DE and NE of corn. Finishing pigs had greater (P < 0.05) growth performance and retention of energy, protein, and lipids than growing pigs. A greater (P < 0.05) DE and NE of diets was observed for finishing pigs than for growing pigs and the DE and NE of corn was also greater (P < 0.05) for finishing pigs than for growing pigs. In conclusion, addition of SBO increases the DE and NE of diets but has no impact on the DE and NE of corn. Diets fed to finishing pigs have greater DE and NE values than diets fed to growing pigs and the DE and NE of corn are greater for finishing pigs than for growing pigs.

The objectives of this experiment were 1) to determine the effect of dietary soybean hulls (SBH) and wheat middlings (WM) on body composition, nutrient and energy retention, and the NE of diets and ingredients fed to growing or finishing pigs and 2) to determine if finishing pigs use the energy in SBH and WM more efficiently than growing pigs. Forty growing barrows (initial BW: 25.4 ± 0.7 kg) and 40 finishing barrows (initial BW: 84.8 ± 0.9 kg) were randomly allotted to 5 groups within each stage of growth. Two groups at each stage of growth served as the initial slaughter group. The remaining pigs were randomly assigned to 3 dietary treatments and harvested at the conclusion of the experiment. The basal diet was based on corn and soybean meal and was formulated to be adequate in all nutrients. Two additional diets were formulated by mixing 70% of the basal diet and 30% SBH or 30% WM. In the growing phase, ADG, G:F, and retention of lipids were greater (P < 0.05) for pigs fed the basal diet than for pigs fed the diets containing SBH or WM. Retention of energy was also greater (P < 0.05) for pigs fed the basal diet than for pigs fed the SBH. In the finishing phase, pigs fed the SBH diet tended (P = 0.10) to have a greater ADG than pigs fed the WM diet, and energy retention was greater (P < 0.05) for pigs fed the basal diet than for pigs fed the WM diet. The NE of the basal diet fed to growing pigs was greater (P < 0.01) than the NE of the diets containing SBH or WM, and there was a tendency for a greater (P = 0.05) NE of the basal diet than of the other diets when fed to finishing pigs. The NE of SBH did not differ from the NE of WM in either growing or finishing pigs, and there was no interaction between ingredients and stage of growth on the NE of diets or ingredients. The NE of diets for growing pigs (1,668 kcal/kg) was not different from the NE of diets for finishing pigs (1,823 kcal/kg), and the NE of the diets containing SBH (1,688 kcal/kg) was not different from the NE of the diets containing WM (1,803 kcal/kg). Likewise, the NE of SBH (603 kcal/kg) did not differ from the NE of WM (987 kcal/kg). In conclusion, inclusion of 30% SBH or WM decreases the performance and nutrient retention in growing pigs but has little impact on finishing pigs. The NE of the diets decreases with the inclusion of SBH and WM, but the NE of diets and ingredients is not affected by the BW of pigs. The NE of SBH is not different from the NE of WM.

Distillers dried grains with solubles (DDGS) has low and variable AA digestibility. The variability is often attributed to damage during the heating process, and it has been suggested that the damage happens to the soluble components of DDGS such as reducing sugars. Combining solubles and grains sometimes produces syrup balls (SB); their digestibil- ity is unknown. The objective of this experiment was to identify potential sources of poor and variable AA digestibility in DDGS. Specifically, our objective was to determine whether the problems are associated with the solubles component or with SB. The ingredients evaluated were DDGS, intact SB, ground SB, liquid condensed solubles (LCS), and pulse dried thin stillage (PDTS) obtained from the same ethanol plant. The LCS is produced by evaporation of thin stillage. Each ingredient was used as the only source of AA in an experimental diet. In a duplicate 6 × 6 Latin square design with 7-d adaptation and collection periods, the 6 treatments consisted of an N-free diet and the 5 test ingredients. Pigs had 5 d of adaptation to each diet, and on d 6 and 7 ileal digesta were collected from an ileal cannula for 8 h each day. Both SB treatments had apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA that were similar or greater (P < 0.05) than those of DDGS. The AID and SID values of Lys and a few other AA were similar in LCS (SID Lys: 63.1%) and DDGS (SID Lys: 61.5%), but the digestibility values of most AA in LCS were less than in DDGS (P < 0.05). The low digestibility of AA in LCS was most pronounced for Met (SID: LCS, 41.9% vs. DDGS, 82.8%). The LCS had less (P < 0.05) AID and SID of CP (SID: 67.8%) than intact SB (SID: 85.2%) and ground SB (SID: 85.9%) as well as all AA. The PDTS generally had the least AID and SID and had less (P < 0.05) CP (SID: 55.3%) and several AA, in- cluding Lys, compared with LCS. In conclusion, the presence of SB does not decrease AA digestibility of DDGS, and the LCS evaluated has less indispensible AA digestibility than DDGS. The LCS has low digest- ibility of AA that seems to not be caused by heat dam- age.

Soares, J. A., Singh, V., Stein, H. H., Srinavasan, R. and Pettigrew, J. E. 2011. SHORT COMMUNICATION: Enhanced distillers dried grains with solubles (DDGS) has greater concentration of digestible and metabolizable energy than DDGS when fed to growing and finishing pigs. Can. J. Anim. Sci. 91: 663–667. To better use distillers dried grains with solubles (DDGS) for non-ruminants, some of the fiber may be removed. The “elusieve” process removes approximately 10% of DDGS material, mostly fiber, yielding enhanced DDGS (E-DDGS). An experiment was conducted to compare the DE and ME in E-DDGS to those in DDGS when fed to growing and finishing pigs. Overall, E-DDGS has greater DE, ME and MEnthan DDGS.

The objectives of this experiment were 1) to determine the NE of soybean oil (SBO) and choice white grease (CWG) fed to growing and finishing pigs, 2) to evaluate the effects of inclusion rate of SBO on the NE by growing and finishing pigs, and 3) to determine if there is a difference in the NE of SBO and CWG between growing and finishing pigs. Forty-eight growing (initial BW: 22.13 ± 1.78 kg) and 48 finishing (initial BW: 84.17 ± 5.80 kg) barrows were used, and they were housed and fed individually. Within each stage of growth, pigs were allotted to 8 outcome groups of 6 barrows based on BW. Within each outcome group, pigs were randomly allotted to 1 of 6 groups. Two groups at each stage of growth served as an initial slaughter group. Pigs in the remaining groups were assigned to 4 dietary treatments and slaughtered at the conclusion of the experiment. The basal diet contained corn, soybean meal, and no supplemental lipids. Three additional diets were formulated by mixing 95% of the basal diet and 5% SBO, 90% of the basal diet and 10% SBO, or 90% of the basal diet and 10% CWG. Average daily gain and G:F for finishing pigs and apparent total tract digestibility of energy for growing and finishing pigs increased (linear, P < 0.05) with lipid content, but was not affected by lipid source. The lipid gain:protein gain ratio and the energy retention also increased (linear, P ≤ 0.05) with lipid content in growing and finishing pigs. There were no interactive effects between lipid content and stage of growth or between lipid source and stage of growth on the NE of diets and the NE of dietary lipids. The NE of diets increased (linear, P < 0.01) with increasing SBO (2,056, 2,206, and 2,318 kcal/kg for diets containing 0, 5, or 10% SBO). The NE of the diet containing 10% CWG (2,440 kcal/kg) was greater (P < 0.05) than the NE of the diet containing 10% SBO. The NE of diets was greater (P < 0.05) for finishing pigs than for growing pigs regardless of lipid content or source. The NE of SBO included at 5% (5,073 kcal/kg) was not different from the NE of SBO included at 10% (4,679 kcal/kg), but the NE of CWG (5,900 kcal/kg) was greater (P < 0.05) than the NE of SBO. The stage of growth had no impact on the NE of SBO or CWG. In conclusion, the NE of lipids is not affected by the content of dietary lipids, but the NE of CWG is greater than the NE of SBO.

This study evaluated whether dietary spray-dried plasma (SDP) can ameliorate inflammation, lethargic behaviors, and impairment of reproduction caused by lipopolysaccharide (LPS) challenge during late pregnancy. Two experiments were conducted with 125 mated female mice (C57BL/6 strain) in each experiment. All mice were shipped from a vendor on the gestation day (GD) 1 and arrived at the laboratory on GD 3. Mice were randomly assigned to dietary treatments with or without 8% SDP in the diet. On GD 17, mice determined pregnant by BW and abdomen shape were randomly assigned to intraperitoneal injections with or without 2 μg LPS. In experiment 1, 17 mice (26.7 ± 1.7 g BW) were identified pregnant and euthanized 6 h after the LPS challenge to measure inflammatory responses in uterus and placenta. In experiment 2, 44 mice (26.0 ± 1.6 g BW) were identified pregnant and euthanized 24 h after the LPS challenge to assess behavior and late-term pregnancy loss. Growth performance and reproductive responses, such as loss of pregnancy, percentage of fetal death, and etc., were measured in all pregnant mice. The LPS challenge increased (P < 0.05) uterine and placental tumor necrosis factor-α and interferon-γ, late-term pregnancy loss, and lethargy score, and decreased (P < 0.05) uterine transforming growth factor-β1, moving time and number of rearing, and growth and feed intake. The SDP decreased (P < 0.05) concentrations of both pro-inflammatory and anti-inflammatory cytokines in one or both tissues, and the lethargy score, and increased (P < 0.05) moving time and number of rearing, growth of pregnant mice, and fetal weight. However, the SDP did not affect late-term pregnancy loss caused by the LPS challenge. Consequently, dietary SDP attenuated acute inflammation and lethargic behaviors of pregnant mice caused by the LPS challenge, but did not affect late-term pregnancy loss after the acute inflammation.

Simulation models have been used productively to aid understanding of animal biology and production systems. Emphasis here is on pig growth models, but the principles apply also to other species and other outcomes. Main applications for such models are direct use within a production system, indirect use across production systems and guidance of research. Most useful models are dynamic and mechanistic; most are deterministic but some gain added utility from stochasticity. Several pig growth models have predicted growth rate, feed efficiency and body and carcass composition from inputs, including protein accretion capacity and diet composition and intake. They have been so successful that now attention can be applied elsewhere. Pigs in commercial production fail to achieve their potential growth, presumably because of various stressors, including disease, and the gap between actual and potential growth is a rich target for future simulation models. Models should address activation of the innate immune system separately from clinical disease. They can provide special benefits from prediction of the impacts of several health-promoting technologies, including those in feed.

An experiment involving 25 experiment stations in the North Central and Southern regions (NCR-42 and S-288, respectively) was conducted to assess the degree of uniformity of diet mixing among stations and to assess the variability among station laboratories in chemical analysis of mixed diets. A fortified corn-soybean meal diet was mixed at each station using a common diet formula (except for vitamin and trace-mineral additions). The diet was calculated to contain 14% crude protein (CP), 0.65% Ca, 0.50% P, and 125 ppm Zn (based on 100 ppm added Zn). After mixing, samples were collected from the initial 5% of feed discharged from the mixer, after 25, 50, and 75% was discharged, and from the final 5% of discharged feed. The five samples were sent to the University of Kentucky, finely ground, and divided into subsamples. Each set of five subsamples from each station was distributed to three randomly selected stations for analysis of CP, Ca, P, and Zn (i.e., each station analyzed five diet sub-samples from three other stations). In addition, two commercial and two station laboratories analyzed composites of the five subsamples from each of the 25 mixed diets. Based on the laboratories that analyzed all diets, means were 13.5, 0.65, and 0.52%, and 115 ppm for CP, Ca, P, and Zn, respectively. Ranges of 11.8 to 14.6% CP, 0.52 to 0.85% Ca, 0.47 to 0.58% P, and 71 to 182 ppm of Zn were found among the 25 diet mixes. The coefficients of variation among the 25 diet samples for CP, Ca, P, and Zn were 4.3, 9.3, 4.1, and 17.4%, and among the 25 laboratories were 3.6, 12.5, 10.7, and 11.1%, respectively. Overall analyses of the five sub samples were, respectively, CP: 13.4, 13.6, 13.4, 13.5, and 13.4% (P < 0.06); Ca: 0.66, 0.67, 0.67, 0.66, and 0.67%; P: 0.50,0.51,0.51,0.50, and 0.50%; and Zn: 115, 116, 112, 113, and 120 ppm (P < 0.001). Diets were not uniformly mixed at all stations (station x sample No. was P < 0.08 for Ca and P < 0.01 for CP, P, and Zn). Among stations, the range of the five samples, expressed as a percentage of the mean and averaged for CP, Ca, P, and Zn, varied from +/- 1.1% (i.e., 98.9 to 101.0%) to +/- 12.9% (84.6 to 110.4%), with an overall average of +/- 5.2%. Neither type nor volume of mixers was related to mixing uniformity. The results suggest that uniformity of diet mixes varies among experiment stations, that some stations miss their targeted levels of nutrients (especially Zn), and that the variability among experiment station laboratories in analysis of dietary Ca, P, and Zn in mixed diets is quite large.

The impact of diet on the microbial composition in the gastrointestinal tract (GIT) has been well documented. However, quantifying the role of the diet in shaping microbial composition in humans has been difficult due to the influence of host genetics and the environment. To test the influence of diets on the GIT microbiome independently of host genotype and environment, two genetically identical co-housed pigs were used in an A-B-A-B design across four 14-day periods using two distinct diets that differed in dietary fiber source, soybean hulls or wheat bran. Shifts in fecal microbiomes were assessed with respect to dietary changes by 454-pyrosequencing analysis using the V3 region of the 16S rRNA genes. Similarity analysis revealed that the GIT microbiome distinctly clustered by diets rather than by individual. Diversity analysis showed that the diet fed had an influence on GIT microbiome diversity, which was host specific. While many bacterial taxa and KEGG orthologs reacted similarly to switches in diet, some bacterial taxa and KEGG orthologs reacted differentially in each of the pigs. While diet changed the GIT microbiome composition of isogenic co-housed pigs, inter-individual variations from epigenetics were not entirely eliminated by the use of cloned pigs.

An experiment was conducted to determine how an E. coli challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 × 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coli, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.

Conventional distillers dried grains with solubles (DDGS-CV), uncooked distillers dried grains with solubles (DDGS-BPX) and high-protein distillers dried grains (HP-DDG) are used in diets for pigs to provide protein and energy. These ingredients may have different effects on body composition and energy retention. Therefore, an experiment was conducted to determine effects of DDGS-CV, DDGS-BPX and HP-DDG on body composition and on retention of protein, lipids, and energy when fed to growing or finishing pigs.The total organ weight was greater (P0.05) for finishing pigs fed the HP-DDG diet than for finishing pigs fed the basal diet or the DDGS-CV diet. Finishing pigs fed the DDGS-CV diet had greater (P0.05) lipid gain than pigs fed the other diets, and the net energy (NE) for DDGS-CV was greater (P0.05) than for DDGS-BPX, but the NE value of HP-DDG was not different from that of DDGS-CV or DDGS-BPX.Inclusion of up to 30% DDGS or HP-DDG in diets fed to growing or finishing pigs will not affect body composition or the retention of energy, protein and lipids, regardless of the stage of growth of pigs. The NE value of DDGS-BPX and HP-DDG is not affected by the stage of growth of pigs, but the NE value of DDGS-CV is greater in finishing than in growing pigs.

Purified diets containing six levels of methionine plus two different levels of cystine (0 and 0.45%) were fed to growing rats to determine the methionine requirements for maintenance and for growth. A model was developed to subdivide the methionine requirement for maintenance from its requirement for growth. In the absence of cystine, the methionine requirement for growth based on weight gain response was 8.41 mg/g live weight gain and the maintenance requirement was 0.38 times metabolic body size (W g 75 ); based on N retention response, the growth requirement was 0.37 mg/mg N gain and the maintenance need was 0.36 mg times metabolic body size. In the presence of 0.45% cystine, the methionine requirement for growth was 3.32 mg/g live weight gain and the maintenance requirement was 0.11 times metabolic body size (W g 75 ); based on N retention, the growth requirement was 0.16 mg/mg N gain and 0.07 times metabolic body size. As a percentage of retained protein, according to these equations, the sulfur-containing amino acids calculate to be 6.0%; the reported sulfur-containing amino acid fraction of rat muscle crude protein is 5.1%. Forty-two percent of the requirement for total sulfur-containing amino acids for growth was comprised of methionine. From these relative requirements with versus without added dietary cystine, we estimated that 59 to 61% of the methionine need for growth can be replaced with cystine whereas 71 to 81% of the methionine need for maintenance can be replaced with cystine.

Purified diets containing six levels of tryptophan were fed to growing rats to determine tryptophan requirements for growth and for maintenance. A mathematical model was employed to subdivide the tryptophan need for maintenance from its requirement for growth. Based on the model relating weight gain to tryptophan intake, the tryptophan need for growth was 2.48 mg/g weight gain and the daily tryptophan need for maintenance (mg) was 0.066 times metabolic body size (W g · 75 ). Based on the model relating nitrogen gain to tryptophan intake, the tryptophan need for growth was 0.11 mg/mg nitrogen retention and the daily tryptophan need for maintenance was 0.078 times metabolic body size (W g · 75 ). Previous tryptophan requirements for growth and for maintenance corresponded very closely with these estimates. As a percentage of deposited protein, according to these equations, tryptophan was calculated to be 1.7%; the reported tryptophan content of rat muscle crude protein is 1.8%

Purified diets containing six levels of histidine were fed to growing rats to evaluate histidine requirements for growth and for maintenance. A model was developed to subdivide the requirement for maintenance from the requirement for growth. Based on weight gain response, the histidine need for growth was 4.02 mg/g weight gain and the daily histidine need for maintenance was .130 times metabolic body size (Wg .75 ). Based on nitrogen gain response, the histidine need for growth was .168 mg/mg N gain and the daily histidine need for maintenance (mg) was .137 times metabolic body size (Wg .75 ). The plateau of plasma histidine concentration was reached at 22 mg intake/day. Previous histidine requirements for growth (for less than 5 g daily weight gain or 120 mg daily N retention) and for maintenance were in very close agreement with these estimates. As a percentage of retained protein, according to theses equations, histidine was calculated to be 2.7%; the reported histidine content of rat muscle CP is 2.85%.

We are investigating the potential use of the pig as a model for the study of atherosclerosis by utilizing APOE sequence information, animal cloning, and establishing a nutritional regimen that tem...

Summary Insufficient energy may contribute to the high mortality rate among piglets. Supplemental fat in the sow's diet during late gestation does not affect the piglets' body stores of carbohydrates at birth but increases slightly carcass fat stores. Supplemental dietary fat during late gestation and(or) lactation increases milk production and the fat concentration of colostrum and milk. This increase in colostral and milk fat increases the survival rate among the piglets if the herd survival rate is relatively low (less than 80%) and the sow consumes at least 1,000 g of fat before farrowing. The importance of continuing the fat supplementation after farrowing has not been established. The increased survival rate does not cause a decrease in the mean piglet weaning weight. Rather, the mean piglet weaning weight appears to increase if the dietary fat concentration is at least 8%. There are practical problems associated with the