PIC Pigs Research Articles

134 Meta-Analysis to Determine the Standardized Ileal Digestible Lysine Requirements of Growing-Finishing Pigs from 11- to 150-kg Utilizing the Ingredients Database of Inra

Abstract A meta-analysis was conducted to determine the standardized ileal digestible (SID) lysine (Lys) recommendations for 11–150 kg PIC pigs housed under commercial conditions utilizing the INRA feed ingredients database. Data from 29 trials dating from 2013 to 2020 utilizing 48,338 pigs were recorded in a database. Number of pens/treatment and pigs/pen ranged from 9 to 16 and 12 to 25, respectively. Sire lines were PIC 337 in 25 trials, PIC 327 in 3 trials, and PIC TR4 and 327 in 1 trial. Dam lines were PIC Camborough in 18 trials and PIC Camborough 29 in 9 trials. The SID Lys levels reported in each trial were used, and the SID Lys to calorie ratio curves were built for both metabolizable energy (ME) and net energy (NE) systems using the feed ingredient composition in INRA for energy levels. The response variables, average daily gain (ADG) and feed efficiency (G:F), were analyzed within 7 phases using generalized linear and non-linear mixed models with heterogeneous variance (Gonçalves et al., 2016). Phases consisted of the following body weight ranges: 11-23, 23-41, 41-59, 59-77, 77-104, 104-127, and 127-150 kg . Each treatment mean within a trial (n = 288) was considered the experimental unit and each trial was used as a random effect. There was no evidence for an interaction between sire lines or dam lines and treatment (P > 0.10). The SID Lys to calorie recommendations are based on the average of the requirement estimates for ADG and G:F. At these levels, approximately 100% of maximum ADG and 99.7% of maximum G:F are achieved. After determining the requirement estimates within each of the 7 weight breaks, a quadratic equation of Lys to calorie ratio was fit for each energy system. The equations are described as: g of SID Lys:Mcal of ME = 0.0001381709 × (weight, kg)2 - 0.0366272129 × (weight, kg) + 4.6073086522; and g of SID Lys:Mcal of NE = 0.0000400092 × (weight, kg)2 - 0.0235648387 × (weight, kg) + 6.2762350341. These data provide the estimated SID Lys requirements for maximal growth performance for PIC pigs from 11- to 150-kg based on the ingredients database of INRA.

170 Meta-analysis to Determine the Standardized Ileal Digestible Lysine Requirements of Growing-finishing Pigs from 11- to 150-kg

Abstract A meta-analysis was conducted to determine the standardized ileal digestible (SID) lysine (Lys) recommendations for 11–150 kg PIC pigs housed under commercial conditions. Data from 29 trials dating from 2013 to 2020 utilizing 48,338 pigs were recorded in a database. Number of pens/treatment and pigs/trial ranged from 9 to 16 and 12 to 25, respectively. Sire lines were PIC 337 in 25 trials, PIC 327 in 3 trials, and PIC TR4 and 327 in 1 trial. Dam lines were PIC Camborough in 18 trials and PIC Camborough 29 in 9 trials. The SID Lys to calorie ratio curves were built for both metabolizable energy (ME) and net energy (NE) systems using the feed ingredient composition in NRC (2012) for energy levels. The response variables average daily gain (ADG) and feed efficiency (G:F) were analyzed using generalized linear and non-linear mixed models with heterogeneous variance (Gonçalves et al., 2016). Each treatment mean within a trial (n = 288) was considered the experimental unit and each trial was used as a random effect. The models were developed for mixed gender pigs and the PIC 337 growth curves were used to estimate the recommendations for barrows and gilts. There was no evidence for an interaction between sire lines or dam lines and treatment (P > 0.10). The SID Lys to calorie recommendations are based on the average for ADG and G:F (Table 1). At these levels, approximately 100% of maximum ADG and 99.4% of maximum G:F are achieved. The NE to ME ratio that results in a similar SID Lys recommendation as a percentage of the diet ranged from approximately 0.72 to 0.74. The updated biological requirements for PIC pigs remained similar compared to previous PIC recommendations (Gonçalves et al., 2017). However, the requirement estimates have been adjusted for late nursery and late finishing phases.

PSV-8 Glucocorticoid receptor agonist (GRA): what is the best delivery method to newly weaned pigs?

Abstract We previously found that i.m. injection of GRA, similar to in-feed antibiotics, improves measures of intestinal integrity, nutrient digestibility, and overall growth performance in nursery pigs. In addition, we have demonstrated that the mitigating effects of GRA on the stress of weaning is predominantly done by subsiding the inflammatory response that often accompanies early weaning. The objective of the current study was to explore the most practical methods for delivering GRA to newly weaned pigs. One-hundred and sixty-seven PIC pigs were weaned at 25 ±1.0 days of age (BW 7 ±1.2 kg), and assigned to fourteen treatments (3-4 pigs /pen; 3 pens/treatment). Seven treatments were tested within two sexes (gilts vs. barrows). The treatments were: 1) i.m. injection of GRA (two injections, 0.2 mg/kg BW at -1 and 3 d post-weaning), 2) two levels of in-water GRA (0.8 and 1.6 ppm), 3) in-feed GRA (2.5 and 5.0 ppm), 4) in-feed antibiotic (ANT, 100 ppm tylosin), and 5) control. Dexamethasone was used as GRA. Pigs had free access to in-feed or in-water GRA or ANT during the 1st-week post-weaning. Parameters of growth performance were measured weekly until the end of the nursery phase. A completely randomized design and repeated measurement ANOVA (PROC MIXED) in SAS were used for statistical analyses. In-water, in-feed, and i.m. GRA treatments resulted in growth performance outcomes comparable to that of in-feed ANT. Relative to CON pigs, both ANT and GRA improved ADG and G: F during the nursery phase (P < 0.05). Among the delivery methods tested, 2.5 ppm of in-feed GRA resulted in superior ADG (GRA vs. CON; 0.29 vs. 0.20 kg/d) and G: F (0.63 vs. 0.40 ± 0.05), compared to the control group (P < 0.02). Collectively, these results suggested that in-feed treatment is the best method for delivering GRA to newly weaned pigs.

Dietary N-Carbamylglutamate supplementation enhances myofiber development and intramuscular fat deposition in growing-finishing pigs

The objective of current study was to investigate the effects of dietary N-Carbamylglutamate (NCG) supplementation on growth performance, carcass characteristics, meat quality and muscle fiber trait of finishing pigs; Methods: A total of 350 female PIC pigs (30.41± 3.24kg) were divided into 2 treatments with 7 replicates of 25 each for a 105-day trial. Two treatment diets included a basal diet (control) and an experimental diet with 0.1% NCG supplementation in the basal diet. Growth performance was evaluated for each phase. Carcass characteristics and meat quality were determined in the last phase.; (3) Results: The results indicated that growth performance was not affected by treatments in all phases(P>0.05). NCG tended to improve dressing percentage (P=0.06). NCG not only increased the longissimus dorsi muscle length and weight, marbling score, intramuscular fat (IMF) level and tenderness, but also decreased drip loss of LM muscle (P<0.05). Mandibular fat index was decreased by NCG (P<0.05). NCG supplementation increased the myosin heavy chain (MyHC) I, MyHC-IIa and fatty acid synthase (FAS) mRNA expression, but decreased myofiber cross-sectional area and muscle fiber diameter (P<0.05); Conclusions: Dietary 0.1% NCG supplementation could improve the carcass trait and meat quality through modulating the genes expression associating with myofiber development and intramuscular fat deposition in finishing pigs.

Dietary guanidinoacetic acid supplementation improved carcass characteristics, meat quality and muscle fibre traits in growing-finishing gilts.

This study was designed to evaluate the effects of guanidinoacetic acid (GAA) on growth performance, carcass characteristics, meat and muscle fibre traits of growing-finishing gilts. 300 female PIC pigs were randomly divided (30.10±2.94kg) into 2 treatments with 6 replicates of 25 each for a 100-day trial. Two dietary treatments were comprised of a control diet and a control diet fortified with 450mg/kg GAA. Growth performance was evaluated for each phase. Carcass characteristics and meat quality were determined at last phase. Gilts had free access to feed and water during the experiment. The result indicated that GAA did not affect growth performance (p>0.05). GAA not only increased longissimus dorsi (LM) muscle weight but also decreased its shear force, b*value and drip loss (p<0.05). Mandibular fat index was decreased by GAA (p<0.05). GAA upregulated myosin heavy chain (MyHC) I mRNA expression with lower myofibre cross-sectional area and fibre diameter in LM muscle (p<.05). In conclusion, GAA can improve carcass characteristics and meat quality by changing muscle fibre characteristics and reducing mandibular fat index in finishing gilts.

357 Bridging the gap between reality and genetic potential in pig performance by nutritional strategies

Abstract The global pork output in 2018 reached over 100 million tons and will continue to grow. However, great gap still exists between current productivity and the full genetic potential of pigs. Our hypothesis was that current nutritional profile could not meet the pig biological requirement, and that modifying nutritional strategies can maximize their genetic potential. To test this hypothesis, three experiments were conducted using fluid feed, fermented feed, and modified nutrient profile, respectively. Experiment 1 utilized 360 DLY weaning piglets with 6 replicate pens per treatment and 30 pigs per pen. Piglets were fed either a solid feed or a fluid feed with the exact same formulation. Results showed that fluid feed significantly increased ADFI by 53% from 245 to 375 g/d and increased ADG by 54% from 183 to 281 g/d from d 23 to 30 (P &amp;lt; 0.001). Experiment 2 utilized DLY weaning piglets fed 3 dietary treatments: Corn-SBM control, control + 75 mg/kg chlorotetracycline, and 12h-fermented control diet with 6 replicate pens per treatment and 3 pigs per pen. Results showed that 12h fermentation significantly increased ADG from 374 to 474 g/d from 35–56 d, reduced FCR from 1.74 to 1.52, and reduced diarrhea occurrence from 24.4% to 6.6% compared to control (P &amp;lt; 0.015). Performance from the fermentation group was also significantly better than the chlorotetracycline group. Experiment 3 utilized 8 individually-housed PIC pigs fed modified nutrient profile to determine performance from 7 to 147 days of age. Results showed that BW reached 26.5, 33, 100, 112.6 kg on d 60, 70, 134, 147, respectively, and overall FCR was 1.93. Results from these experiments demonstrated that the genetic potential of pig can be realized in greater extend by nutritional strategies.

The significance of the diversity and composition of the cecal microbiota of the Tibetan swine

The Tibetan swine (TIS) is a non-ruminant herbivore with high disease resistance. Also, it has the ability to digest plants with high fiber content. However, it is not known whether any relationship exist between these characteristics of the TIS and its cecal microbiota. Thus, this study aims to investigate the cecal microbiota of the adult TIS using high-throughput sequencing techniques in order to explore possible relationships between these unique characteristics of the TIS (high disease resistance and ability to digest high fiber plants) and its cecal microbiota. PIC pigs (lean type) were chosen as controls. The results show that 75,069 valid sequences of the 16S rRNA gene at V4-V5 region were obtained in the cecal content of TIS. They were composed of 15 phyla, 70 genera and divided into 660 Operational Taxonomic Units (OTUs). Bacteroidetes and Firmicutes were the predominant phyla in both breeds, but TIS had more Bacteroidetes than Firmicutes. Also, 42.4% of the cecal bacteria were found to be unclassified and uncultured. Many cellulolytic bacteria were also found in the two breeds. TIS (88.10%) had much higher abundance in the core bacterial communities than PIC pigs (81.29%), and the proportion of Bacteroides and Spirochaetes that can effectively degrade cellulose were 6.01 and 6.40% higher than PIC pigs, respectively, while Proteobacteria that are closely related to gastrointestinal diseases were 1.61% lower than PIC pigs. Thus, the disease resistance of the TIS and its ability to digest plants with high fiber content may be related to high abundance of core bacterial communities as well as the large number of unknown and unclassified bacteria.

Effects of increased vertebral number on carcass weight in PIC pigs.

Variation of the vertebral number is associated with carcass traits in pigs. However, results from different populations do not match well with others, especially for carcass weight. Therefore, effects of increased vertebral number on carcass weight were investigated by analyzing the relationship between two loci multi-vertebra causal loci (NR6A1 g.748 C > T and VRTN g.20311_20312ins291) and carcass weight in PIC pigs. Results from the association study between vertebral number and carcass weight showed that increased thoracic number had negative effects on carcass weight, but the results were not statistically significant. Further, VRTN Ins/Ins genotype increased more than one thoracic than that of Wt/Wt genotype on average in this PIC population. Meanwhile, there was a significant negative effect of VRTN Ins on carcass weight (P<0.05). Thus, our results suggested negative effect of increased thoracic number on carcass weight in PIC pigs.

The influence of polyethylene glycol inclusion in &lt;i&gt;Vachellia tortilis&lt;/i&gt; leaf meal on nitrogen balance in growing pigs

The incorporation of polyethylene glycol (PEG), a tannin binding agent, in high tannin feedstuff is known to prevent tannin-protein complexes. Environmental contamination with nitrogen-containing products in manure is a topical issue in the tropics. The objective of the study was to determine the extent to which the incorporation of PEG in Vachellia tortilis leaf meal improved nitrogen balance, serum iron, and phosphorus in growing pigs. Forty-eight clinically healthy male PIC pigs (31.3 ± 1.28 kg; Landrace x Large White) were allotted to individual pens in a completely randomized design, with eight pigs per treatment. They were offered a diet that contained 150 g V. tortilis /kg dry matter (DM). The diets were treated with 0, 5, 10, 15, 20, and 25 g PEG/kg. As PEG inclusion increased, serum iron concentration also rose until it reached a plateau. Nitrogen (N) utilisation and retention significantly increased linearly with PEG inclusion. Nitrogen excretion through faeces and urine significantly decreased linearly when increasing the amount of PEG in V. tortilis leaf meal in feed offered to pigs. Nitrogen utilization significantly increased linearly as the inclusion of PEG rose. It can be concluded that the inclusion of PEG increased N balance. Keywords: average daily gain, nitrogen intake, nitrogen retention, phytate, polyphenolic compounds

273 Standardized ileal digestible lysine requirements for finishing PIC pigs under commercial conditions: A meta-analysis

273 Standardized ileal digestible lysine requirements for finishing PIC pigs under commercial conditions: A meta-analysis

Live performance, carcass quality, and economic assessment of over 100kg slaughtered pigs

Recent genetic improvement has developed pigs with maximum potential for protein deposit at higher weights; however, their optimal slaughter weight still needs to be determined. The objective of the study was to evaluate live performance, carcass traits, and economic viability of 417 Agroceres PIC pigs slaughtered with 100, 115, 130, and 145kg live weight. Pigs were reared in pens with 10-11 barrows and gilts each, offered a feed allowance of 2.8kg/pig/day until the following slaughter weights (SW): 99.65±0.82kg, 118.53±0.98kg, 133.97±1.17kg, and 143.90±1.24. There was no interaction between sex and SW (P&gt;0.05). Backfat thickness, fat area, and loin eye area linearly increased with SW (P&lt;0.001; R2: 70.12-77.44%), and carcass yield increased in a quadratic manner (P&lt;0.001; R²=24.66%). Lean yield was not affected (P&gt;0.05), and feed conversion ratio (R²=43.29%) linearly worsened with SW (P&lt;0.001), but the effect of SW on live production cost (R$/kg) was quadratic, with the minimum point at 134.8kg. It was concluded that, under the applied management, increasing SW results in larger amount of lean tissue with no change in its yield and little effect on growth performance.

Effects of dietary supplementation with two potassium formate sources on performance of 8- to 22-kg pigs

Dietary inclusion of salts of organic acids may modulate intestinal microbiota and enhance performance of pigs. Published data on the effects of potassium formate (KF; pH 6.0-8.5) on pig performance are scarce compared with that of potassium diformate (KDF; pH 4.1-4.5). Therefore, the objective was to evaluate the effects of KDF or KF supplementation on performance of 8- to 22-kg pigs. A 35-d growth trial was conducted with 144 PIC pigs (initial BW of 7.9 ± 0.69 kg) with 6 pigs (3 gilts and 3 barrows) per pen and 8 pens per treatment. Pigs were assigned to 3 diets based on corn (Zea mays), wheat (Triticum aestivum), and soybean (Glycine max) meal for each of the prestarter (days 1-14) and starter phases (days 15-35). The basal diet was supplemented with KDF at 1.20% or KF at 1.56% replacing corn starch to create diets 2 and 3, respectively, to provide a constant formate content. The ADG and feed conversion ratio (FCR) were not affected by the addition of KDF or KF during the prestarter phase. Addition of KDF or KF to the basal diet increased (P < 0.01) ADG and final BW and improved FCR (P < 0.05) during the starter and the overall 35-d period. The ADFI was not affected by the treatments. Performance of pigs fed diets supplemented with KF and KDF were similar. Diarrhea incidences were observed during week 1 but no differences were observed (P > 0.05) among treatments in term of the number of antibiotic treatments or fecal consistency scores. Overall, the supplementation of 1.56% KF or 1.20% KF improved performance of weaned pigs.

Feeding diets based on barley or triticale during fattening of high-meat PIC pigs: Effects on carcass characteristics and meat quality parameters

This study was conducted to compare performance, carcass and meat quality parameters in high-meat fattening hybride PIC pigs fed barley or triticale based diets. Sixty, 12 week old weaner piglets of similar mean body weight (30 kg ± 0.4) were randomly divided into two groups of 30 each, and assigned to one of the two dietary treatment groups designated as group B (fed bar ley based diets) and group T (fed triticale based diets). The pigs fed T based diets showed 8% higher growth rate (p<0.05) at 11% lower feed conversion ratio. Post slaughter parameters in pigs fed triticale based diets were more desirable than in those fed barley based diets. T fed pigs had higher loin eye area and smaller suet weight (p<0.01). Dressing percentage, carcass length, fleshiness, back fat thickness, dry matter, crude ash, crude protein and ether extract and pH of meat were similar in both groups. Meat from T fed pigs had slightly darker colour of m. semimembranosus, and higher water holding capacity of m. longisimus lumborum (p<0.05). Feeding triticale based diets to PIC pigs has beneficial effects on performance and characteristics carcass. Triticale could totally replace barley in rations for fattening high meat PIC swine.

Chloride intracellular channel 5 modulates adipocyte accumulation in skeletal muscle by inhibiting preadipocyte differentiation

Intramuscular fat, the total lipid deposited within skeletal muscle, has been regarded as a potential factor responsible for meat quality in animal production and insulin resistance in humans. The objective of present study was to identify candidate genes which control intramuscular fat accumulation through using animal models. PIC pigs (lean-type) and Rongchang pigs (obese-type) were used. By scanning the mRNA samples of longissimus dorsi muscle with Affymetrix Gene-Chip microarray technology, sus scrofa chloride intracellular channel 5 (CLIC5) was isolated, and its mRNA abundance and protein expression level were reversely related with the intramuscular fat content of pigs. Furthermore, over-expression of CLIC5 dramatically increased the proliferation of 3T3-L1 preadipocytes, while inhibited adipocytic differentiation accompanied by the down-regulation of c/EBPalpha, LPL, and PPARgamma protein. Our results suggest that CLIC5 might be a crucial regulator of adipose accumulation in skeletal muscle of pigs.

The mRNA of lipin1 and its isoforms are differently expressed in the longissimus dorsi muscle of obese and lean pigs

Lipin1 has been documented to play an important role in adipogenesis. In the present study, the mRNA expression level of lipin1 and its isoforms in longissimus dorsi muscle were determined by semi-quantification RT-PCR in lean PIC and obese Rongchang pigs. Further, we determined mRNA expression for lipin1 and its two isoforms in Rongchang obese pigs which had either a high or low intramuscular fat content. We demonstrate for the first time that porcine lipin1 has two alternative forms, lipin-α and lipin-β. Unlike mice and humans where the lipin-β has 99 more nucleotides than lipin-α, we found that in swine, lipin-β has 108 more nucleotides than lipin-α. Our results indicate that the longissimus dorsi muscle of Rongchang obese pigs have a higher level of mRNA expression for lipin1 and its isoforms than PIC lean pigs. Furthermore, Rongchang pigs with higher intramuscular fat content had a higher lipin1 and lipin-β mRNA expression in longissimus dorsisi muscle than Rongchang pigs with lower intramuscular fat content (P<0.05), whereas no difference was seen in lipin-α mRNA expression between Rongchang pigs with high or low intramuscular fat. The ratio of lipin-β mRNA to lipin-α mRNA was also significantly different between Rongchang pigs distinguished by a high intramuscular fat content compared with those with low intramuscular fat (P<0.05). These data suggested that the lipin1 gene may have a crucial effect on body lipid accumulation in pigs, whereas the lipin-β isoform may play an important role in intramuscular fat deposition in obese pigs.

Effects of Lower Dietary Lysine and Energy Content on Carcass Characteristics and Meat Quality in Growing-finishing Pigs

Fifty-four PIC barrows were used to evaluate the effects of lower dietary lysine content and energy level on carcass characteristics and meat quality in slaughter pigs. Pigs were allotted to one of three treatments by body weight with six replicate pens in each treatment. The dietary treatments for body weights of 20-50 kg, 50-80 kg and 80-90 kg were as follows, respectively: control diet (digestible energy 14.22 MJ/kg, lysine/DE 0.67 g/MJ, 0.53 g/MJ and 0.42 g/MJ); a low lysine group (digestible energy 14.22 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ); and a low lysine-low energy group or low nutrient group (digestible energy 13.11 MJ/kg, lysine/DE 0.49, 0.38 and 0.30 g/MJ). The daily weight gain, daily feed intake and feed efficiency were calculated in the overall growth period (nearly 12 weeks). Meanwhile, carcass characteristics and meat quality were evaluated at 60 and 90 kg body weight respectively. During the overall growth trial, lowering dietary lysine and nutrient level both decreased weight gain (p<0.05) and feed efficiency (p<0.01). At 60 kg body weight, decreasing dietary lysine and nutrient level noticeably decreased dressing percentage (p<0.01) and back fat depth at last rib of PIC pigs (p<0.01), but enhanced marbling scores (p<0.10), intramuscular fat content (p<0.10) and water loss rate (p<0.01) of the longissimus dorsi muscle. At 90 kg body weight, lean percentage (p<0.01) was evidently reduced by both lowering lysine content and nutrient level in the diet. However, the shoulder back fat depth (p<0.05) and marbling scores of the loin eye muscle (p<0.05) were increased; Lowering dietary nutrient level could improve back fat depth of 10th rib (p<0.01) and last rib (p<0.01), intramuscular fat content (p<0.10), redness (p<0.01) and water loss rate of the loin eye muscle (p<0.05), but decrease loin area (p<0.05). Finally, when comparing the 60 kg and 90 kg slaughter weights, it was found that the shoulder back fat depth (p<0.01, p<0.10), 6th-7th rib (p<0.01, p<0.01), 10th-rib (p<0.01, p<0.01) and last rib back fat depth (p<0.01, p<0.01) of the low lysine and low nutrient group were all obviously increased comparing with the control group. Taken together, the results showed that decreasing dietary lysine content and nutrient level increased intramuscular fat content and water loss rate of longissimus dorsi muscle; On the other hand, both lowering dietary lysine and nutrient level markedly compensated to increase back fat deposition in the later finishing period (body weight from 60

Effects of dietary cysteamine supplementation on growth performance and whole-body protein turnover in finishing pigs

The objective of this study was to investigate the effects of dietary cysteamine (CS) supplementation on growth performance and whole-body protein turnover in finishing pigs. This experiment contained 2 trials with the first trial of effect of dietary cysteamine supplementation on growth performance in finishing pigs for 47 d. A total of 16 PIC pigs (60.02 ± 1.01 kg; eight gilts and eight barrows) were randomly assigned to one of two dietary groups, with four pens per group (per pen: one gilt, one barrow). In the second trial, a total of eight PIC barrows (60.04 ± 1.02 kg) were randomly assigned to one of the two dietary groups, with four pens/group (one pig/pen) for 37 d and then the eight barrows were housed individually in metabolism crates (four barrows in control group and four barrows in CS group) for 10 d. The pigs of the first and second trials were fed a basal diet containing 0 (control) or 70 mg CS/kg diet. A total of eight barrows of the second trial received a 7-d nitrogen balance trial. 15 N-Glycine (10 mg/kg BW) was gastrically infused after d 5 of the nitrogen balance trial. Feces and urine were collected daily to determine the N output. Results indicated that CS supplementation increased ( P < 0.05) average daily gain (ADG), feed intake (ADFI), nitrogen retention, nitrogen retention efficiency, and efficiency of digestible N utilization. In addition, CS supplementation resulted in a decreased ( P < 0.05) protein breakdown rate. Net protein gain in nitrogen was increased ( P < 0.05) by 63.5%. However, protein synthesis rate, nitrogen flux, and endogenous urinary nitrogen were not affected ( P > 0.05). It is concluded that dietary CS supplementation may improve growth performance in finishing pigs. Protein deposition is increased after dietary CS supplementation. This increase is caused by a decrease in protein breakdown.

The optimal true ileal digestible lysine and total sulfur amino acid requirement for nursery pigs between 20 and 50 lb (2005)

An experiment involving 360 pigs (PIC, avg. BW = 22.0 lb) was conducted to determine the appropriate true ileal digestible (TID) lysine and total sulfur amino acid (TSAA) requirement of nursery pigs and, consequently, to determine the optimal TSAA:lysine ratio. This trial was organized as a combination of two simultaneous experiments, with one set of diets consisting of five increasing TID lysine concentrations (1.05, 1.15, 1.25, 1.35, and 1.45%) and the second set of diets consisting of five increasing TID TSAA concentrations (0.61, 0.69, 0.76, 0.83, and 0.90%). The highest concentrations of both lysine and TSAA (1.45% and 0.90%, respectively) were combined as one diet and used in both the lysine and TSAA titrations, to give a total of 10 treatments. Pigs were randomly allotted to eight replications, with five pigs per pen, on the basis of initial BW. Average daily gain and F/G improved (quadratic, P<0.01) with increasing TID lysine. The largest improvement in growth rate and feed efficiency for PIC pigs in these facilities occurred as the TID lysine increased to 1.25 and 1.35%, respectively; there was little improvement in performance thereafter. Increasing TID TSAA increased (quadratic, P<0.01) ADG and improved (quadratic, P<0.01) F/G, although the largest increases in ADG and F/G occurred as TID TSAA increased from 0.61 to 0.76%, with smaller improvements from 0.76 to 0.90%. Average daily gain and F/G values were plotted as the dependent variables in a regression analysis, with the TID lysine and TSAA concentrations on the Y axis. Regression analysis of the response surface resulted in an estimated TID TSAAto-lysine ratio range of approximately 55 to 56% for optimal ADG and F/G.

Determining the optimal lysine:calorie ratio for growth performance of PIC nursery pigs (2005)

Two studies were conducted to evaluate the effects of increasing dietary lysine and energy density on nursery pig performance. Experiment 1 was organized as a combination of two simultaneous experiments,with one set of diets consisting of five treatments with increasing true ileal digestible (TID) lysine (1.11, 1.19, 1.26, 1.34, and 1.42%) and the second set of diets consisting of five treatments with increasing energy density (1,341, 1,408, 1,475, 1,542, and 1,609 kcal/lb). The highest level of both lysine and energy density (1.42% and 1,609 kcal/lb, respectively) were combined as one diet and used in both the lysine and energy-density titrations, to give a total of 9 diets for the 10 treatments. Pigs (PIC, avg BW = 22.5 lbs) were randomly allotted to eight replications with five pigs per pen, on the basis of BW. Overall (d 0 to 21) in Experiment 1, increasing TID lysine linearly increased (P<0.01) ADG and improved (linear, P<0.01) feed efficiency. Increasing energy density had no effect on ADG, but it decreased (linear, P<0.01) ADFI, which resulted in a linear (P<0.01) improvement in F/G. Regression analysis of the response surface was used to predict the optimal lysine: calorie ratios for ADG and F/G of 4.06 and 3.92 g lysine/Mcal ME for the PIC pigs used in this experiment. In Experiment 2, pigs (PIC, avg BW = 16.6 lbs) were fed diets with two different energy densities (1.34 or 1.49 Mcal ME/lb) with TID lysine:calorie ratios ranging from approximately 3.5 to 4.5 g/Mcal ME. There was an energy density × TID lysine:calorie ratio interaction observed for F/G. Pigs fed the low-energy diets had the greatest ADG, at a lysine: calorie ratio of 4.55. For pigs fed the high-energy diets, ADG improved as the lysine:calorie ratio improved to 4.26 g of TID lysine/Mcal ME. There was a quadratic (P<0.03) improvement in feed efficiency as the lysine:calorie ratios were increased for the pigs fed the low-energy diet, with the best F/G value observed at 4.55, but the pigs fed the high-energy diets experienced a linear (P<0.01) improvement in F/G as the lysine:calorie ratios were increased. These results suggest that the optimal lysine-to-calorie ratio is 4.26 to 4.55 g of TID lysine/Mcal ME for 20- to 50-lb PIC pigs in these facilities.; Swine Day, 2005, Kansas State University, Manhattan, KS, 2005

Effect of β-glucanase supplementation of cereal-based diets for starter pigs on the apparent digestibilities of dry matter, crude protein and energy

A total of 48 PIC pigs (Camborough × Canabrid), average body weight 6.2 kg and 24 d of age, were allotted to four experiments (12 pigs each, equal numbers of barrows and gilts) to determine the effect of β-glucanase supplementation on the digestibilities of crude protein and energy in cereal-based soybean meal diets without or with supplementation of β-glucanase at 0.05, 0.1 and 0.2% (wt./wt.). The experimental diets were formulated to contain 200 g crude protein kg −1 based on soybean meal and barley (B + SBM, experiment 1), wheat (W + SBM, experiment 2), corn (C + SBM, experiment 3) or rye (R + SBM, experiment 4), respectively. Chromic oxide was used as digestibility marker. Each experiment was carried out according to a balanced two-period change-over design. The pigs were fed 3 times daily, equal amounts, at 08:00, 16:00 and 24:00 h, at a rate of 5% (wt./wt.) of the individual body weight which was determined at the beginning of the first (6.2 kg) and second (8.1 kg) experimental period. Each experimental period lasted 10 days with 7 days of adaptation followed by 3 days of faeces collection. There was a linear increase ( P < 0.05) in the digestibilities of dry matter, crude protein and energy when β-glucanase was supplemented to the B + SBM diets. The digestibility of crude protein increased ( P < 0.05) from 81.6 to 88.5% when 0.2% β-glucanase was supplemented; the digestibility of energy increased ( P < 0.05) from 85.2 to 89.5%. There was no effect ( P > 0.05) of β-glucanase supplementation on the digestibilities of crude protein and energy in the W + SBM, C + SBM and R + SBM diets.