Average Daily Gain Feed Intake Research Articles

The impact of essential fatty acid ratios and unsaturated to saturated fat ratio on growth performance of grow-finish pigs and estrus detection of gilts.

The objective of this study was to investigate the effects of dietary unsaturated and saturated fat ratio (U:S) and the ratio of linoleic and linolenic acid (LA:ALA) on the growth performance of grow-finish pigs and estrus detection of gilts. A total of 240 pigs with initial body weight (BW) 54.4 ± 5.5 kg were randomly assigned to a high (>1.8; HUS) or low (<1.0; LUS) U:S in combination with a high (20:1), moderate (12:1), or low (4:1) LA:ALA in a 3 × 2 factorial arrangement. Dietary ratios were achieved using blends of choice white grease, beef tallow, corn oil, flaxseed oil, or palm kernel oil. Diets were fed across three phases and balanced for energy and LA. Pigs were housed across 60 pens with either four gilts or four barrows per pen. On day 49, 1 gilt per pen was moved to individual housing at approximately 154 d of age for evaluation of reproductive characteristics. Data were analyzed as repeated measures using PROC MIXED (SAS 9.4; SAS Inst., Cary, NC) with pen as the experimental unit and U:S, LA:ALA, sex, and their interactions as fixed effects. Initial BW was fit as a covariate. Within each phase, there were no differences in BW, daily gain (ADG), feed intake (ADFI), or feed efficiency (G:F) for U:S, LA:ALA, or their interaction when averaged across sex (P ≥0.128). Gilt feed efficiency was improved during the second phase compared to barrows; however, feed efficiency was not different between barrows and gilts during the first and third phases; resulting in a similar feed efficiency between sexes for the overall period (P = 0.523). Compared to HUS, gilts receiving LUS had higher ADFI overall (P = 0.018), which translated into improved G:F for HUS gilts (P = 0.011). Overall, gilts receiving the 20:1 diet tended to have improved G:F compared to 12:1 (P = 0.086). ADG was improved in pigs fed diets formulated with unsaturated fat sources to a 20:1 LA:ALA, regardless of sex. Detection of first estrus by 235 d of age in gilts was not impacted by U:S or LA:ALA (P ≥ 0.356). In conclusion, feeding differing dietary U:S and LA:ALA ratios impacts growth of growing pigs, particularly improving feed efficiency of gilts fed diets with unsaturated fat sources or a 20:1 LA:ALA. Further investigation into the physiological mechanisms differentially affecting gilt growth when fed varying dietary LA:ALA is warranted to understand the impact on reproductive outcomes.

PSVII-8 The Impact of Dietary Essential Fatty Acids Ratios and Unsaturated:Saturated Ratio on Growth Performance of Grow-Finish Pigs

Abstract The objective was to investigate the effects of dietary unsaturated:saturated fat ratio (U:S) and the fatty acid ratio of linoleic acid:linolenic acid (n6:n3) on growth performance of grow-finish pigs. A total of 240 pigs with initial body weight (BW) 54.4±5.5kg were randomly assigned to a high (&amp;gt; 1.8; HUS) or low (&amp;lt; 1.0; LUS) U:S ratio with a high (20:1), moderate (12:1) or low (4:1) n6:n3 in a 3×2 factorial design (n = 10). Diets were fed across 3 phases and balanced for energy and linoleic acid. Pigs were housed 4 pigs per pen and separated by sex. Data were analyzed as repeated measures using SAS (9.4) with pen as the experimental unit and U:S ratio, n6:n3 ratio, sex, and their interactions as fixed effects. Initial BW was fit as a covariate. Within each phase, there were no differences in BW, daily gain (ADG), feed intake (ADFI) or feed efficiency (G:F) for U:S, n6:n3, or their interaction (P &amp;gt; 0.10). For the overall period, there was a U:S×n6:n3 interaction for ADG (P &amp;lt; 0.05) with pigs receiving LUS×12:1 (1.19kg/d) having increased ADG compared with pigs receiving HUS×12:1 (1.12kg/d). There was no effect of sex (P &amp;gt; 0.10) for G:F within each phase; however, overall, gilts had improved G:F compared with barrows (P &amp;lt; 0.05). Compared with HUS, gilts receiving LUS had greater ADFI overall (P &amp;lt; 0.05; 2.84 vs. 2.70kg), which translated into improved G:F for HUS gilts (P &amp;lt; 0.05; 0.40 vs 0.39). Overall, gilts receiving the 20:1 diet tended to have improved G:F compared with 12:1 (P &amp;lt; 0.10; 0.40 vs 0.39). The dietary U:S ratio impacted overall ADG of pigs fed the 12:1 ratio when averaged across sex; however, there was no significant sex × U:S × n6:n3 interaction. A low U:S ratio can also increase feed intake of gilts; however, this did not result in improved ADG.

Ileal alkaline phosphatase is upregulated following functional amino acid supplementation in Salmonella Typhimurium-challenged pigs.

We recently showed that functional amino acid (FAA) supplementation improves growth performance and immune status of Salmonella Typhimurium (ST)-challenged pigs, which was further improved by a longer adaptation period. It is expected that the effects are associated with increased activity of intestinal alkaline phosphatase (IAP). The objective of this study was to evaluate the effects of FAA supplementation and adaptation period on the ileal, cecal, and colonic activity of IAP in weaned pigs challenged with ST. In experiment 1, a total of 32 mixed-sex weanling pigs were randomly assigned to dietary treatments in a 2 × 2 factorial arrangement with low (LP) or high protein (HP) content and basal (FAA-) or FAA profile (FAA+; Thr, Met, and Trp at 120% of requirements) as factors. In experiment 2, a total of 32 mixed-sex weanling pigs were randomly assigned to one of four dietary treatments, being FAA- fed throughout the experimental period (FAA-) or an FAA profile fed only in the post-inoculation (FAA + 0), for 1wk pre- and post-inoculation (FAA + 1), or throughout the experimental period (FAA + 2). In experiments 1 and 2, after a 7- and 14-d adaptation period, respectively, pigs were inoculated with saline solution containing ST (3.3 and 2.2 × 109 CFU/mL, respectively). Plasma alkaline phosphatase was measured on days 0 and 7 post-inoculation in experiment 1, and IAP (ileum, cecum, and colon) was measured in experiments 1 and 2. Correlations among ileal IAP and serum albumin and haptoglobin, plasma superoxide dismutase (SOD), malondialdehyde (MDA), and reduced:oxidized glutathione, ileal myeloperoxidase, ST shedding and ileal colonization, and post-inoculation average daily gain, feed intake (ADFI), and gain:feed were also analyzed. In experiment 1, plasma alkaline phosphatase was decreased with ST inoculation and the overall content was increased in LP-FAA+ compared with LP-FAA- (P < 0.05). Moreover, ileal IAP was increased in FAA+ compared with FAA- pigs in both studies (P < 0.05) regardless of adaptation time (P > 0.05). IAP was positively correlated with MDA and ADFI and negatively correlated with SOD and ST shedding in experiment 1 (P < 0.05). These results demonstrate a positive effect of FAA supplementation, but not adaptation period, on ileal alkaline phosphatase activity in Salmonella-challenged pigs, which may be associated with improvements in antioxidant balance.

PSIII-20 Inclusion of a Live Yeast to Mixed Cereal Diets Improves Growth Performance of Nursery Pigs

Abstract As an alternative to antibiotic growth promoters, live yeast supplementation has proven useful in reducing weaning stress and improving health and performance of piglets. The objective of the study was to evaluate the effect of a high concentrated live yeast product (20 billion CFU/g) supplemented in post-weaning piglet diets without antibiotics. A total of 144 pigs Pietrain × [LW×Landrace] (average initial BW = 8.55 ± 1.5 kg) weaned at 28 days of life were used for a 6-week growth study to determine post-weaning performance. Pigs were assigned to 2 treatments; 0 (Control group; CT) and 1 g of live yeast/kg (Yeast Supplemented group; YS) feed to 12 replicate pens of 6 pigs (3 barrows; 3 gilts). Average daily gain (ADG), feed intake (ADFI) and feed conversion ratio (FCR) were evaluated in pre-starter (days 0–14), starter (days 14–42) and in the whole nursery (days 0–42) periods. Data were analysed with ANOVA using PROC MIXED of SAS according to the completely randomized design. The model included initial BW as a covariant. Differences were deemed statistically significant when P ≤ 0.050 using a one tailed t-test. Live yeast supplementation improved ADG in starter (5.8%; P = 0.034) and in the whole nursery periods (7.0%; P = 0.045) compared with the CT group. Consequently, final BW was also higher in supplemented animals than in the CT (4.5%; P = 0.034). Differences in ADG were associated with differences in ADFI, higher in YS than in the CT group, both in starter (6.4%; P = 0.023) and in the whole nursery period (6.5%; P = 0.030). No differences were observed for FCR, mortality rate, and health incidences between dietary treatment groups. Therefore, supplementation of a live yeast to post-weaned piglets improved growth performance, confirming this product as an alternative to reduce antibiotic usage in nursery piglets.

PSIII-19 The Effect of Xylanase on Finisher Pig Performance

Abstract The breakdown of long chain arabinoxylans into smaller chain xylo-oligomers by the use of xylanase results in a shift towards fiber utilizing bacteria resulting in production of small chain fatty acids and improved pig performance. The objective of this study was to evaluate the effect of xylanase (Econase XT; AB Vista) on finisher pig performance. A total of 598 pigs; (37.4 ± 1.0 kg) were fed a single-phase diet for 60 days. Pigs were assigned to two treatments; 0 (CTL) or 16,000 BXU/kg of xylanase (XYL) with 12 pen replicates and 24/25 pigs (mixed sex; gilts and boars) per treatment. The diet was based on wheat, barley, soybean meal, rapeseed meal, and wheat midds; SID Lys: 0.88%, NDF: 14.7%, and NE: 2090 kcal/kg. Average daily gain (ADG), feed intake (ADFI) and feed conversion ratio (FCR) were evaluated in phase 1 (0-26d), phase 2 (26-60d) and overall (0-60d). Liveability was measured per treatment. Data were analysed using JMP 12 using the standard least square platform and ANOVA was performed to determine significance at P &amp;lt; 0.05. The model included initial BW as a covariant. The results indicated that there was no effect of xylanase on liveweight, ADG or ADFI at any phase of the finisher period. The use of xylanase improved FCR in phase 2 (2.53 v 2.60: P &amp;lt; 0.05) and overall (2.44 v 2.49 P=0.03). No differences were seen in liveability (CTL; 96%; XYL 98%; P = 0.29). It can be concluded that the use of xylanase can be used in finisher feeds to improve FCR which is linked with greater energy utilisation that has been associated with greater fiber breakdown through xylanase use.

Effects of spray‐dried animal plasma on the growth performance of weaned piglets—A review

Spray-dried animal plasma sourced from bovine, porcine or other animal origin is often used as a main feed ingredient in the diets of weanling piglets to improve growth performance. The objective of this study was to determine the effect of animal plasma in diets on the performance of piglets in the post-weaning period, with and/or without pathogenic challenge, by undertaking a meta-analysis. Data were extracted from peer-reviewed reports published in scientific journals. The average initial weight of the piglets was 5.8kg and the average initial age 19days (2-56days). The average duration of feeding animal plasma was 40days. Average daily gain (ADG), feed intake (ADFI) and feed conversion ratio (FCR) were found to be 22-28g/day, 20-27g/day and -0.28 to 0.06g/g. Generally, diet supplemented with spray-dried bovine plasma (SDBP) improved the ADG of the piglets and spray-dried porcine plasma (SDPP) led to increases in the ADFI. For the first week post-weaning alone, as the dietary animal plasma percentage increased there was an increase in ADG and ADFI; similarly, the latter two measures increased as weaning age increased. The evidence suggests that mainly IgG present in animal plasma prevents the binding of pathogens to the gut wall and reduces the incidence of sub-clinical infection in the post-weaning stage. Animal plasma containing IgG appears to be a useful in-feed supplement for piglets in the post-weaning phase.

Genetic analysis of disease resilience in wean-to-finish pigs from a natural disease challenge model.

The objective was to estimate the genetic parameters of performance and resilience of growing pigs under disease. Data were from 3,139 Yorkshire × Landrace wean-to-finish pigs that were exposed to a natural polymicrobial disease challenge that was established by entering naturally infected animals into a nursery barn, targeting various viral and bacterial diseases. The challenge was maintained by entering batches of 60 or 75 healthy nursery pigs every 3 wk in a continuous flow system. Traits analyzed included average daily gain (ADG), feed intake (ADFI) and duration (ADFD); feed conversion ratio (FCR); residual feed intake (RFI); mortality (MOR); number of health treatments (TRT); health scores (HScore); carcass weight (CWT), back fat (CBF) and loin depth (CLD); dressing percentage (DRS); lean yield (LYLD); day-to-day variation in feed intake and duration (VARFI and VARDUR); and the proportion of off-feed days (OFFFI and OFFDUR). Analyses were performed by mixed linear models with genomic relationships. The resilience traits, such as TRT, MOR, and HScore, were lowly heritable (up to 0.15) but had high genetic correlations with each other. Performance traits, such as ADG, ADFI, ADFD, FCR, RFI, and carcass traits, were moderate to highly heritable (0.17 to 0.49). Heritabilities of resilience indicator traits such as OFF and VAR had low to moderate heritabilities (0.08 to 0.23) but were higher when based on duration vs. amount. ADFI had a low genetic correlation with ADFD (0.13). ADG in the challenge nursery had stronger negative genetic correlations with both TRT and MOR than ADG in the finisher (-0.37 to -0.74 vs. -0.15 to -0.56). ADFI and FCR had moderate negative (-0.21 to -0.39) and positive (0.34 to 0.49) genetic correlations, respectively, with TRT and MOR. ADFD and RFI had very low genetic correlations with TRT and MOR. CWT and DRS were moderately negatively correlated with TRT and MOR (-0.33 to -0.59). Resilience indicator traits based on feed intake or duration had moderate to high positive genetic correlations with TRT (0.18 to 0.81) and MOR (0.33 to 0.87). In conclusion, performance and resilience traits under a polymicrobial disease challenge are heritable and can be changed by selection. Phenotypes extracted from feed intake patterns can be used as genetic indicator traits for disease resilience. Most promising is day-to-day variation in intake duration, which had a sizeable heritability (0.23) and favorable genetic correlations with MOR (0.79) and treatment rate (0.20).

Growth performance and hematology characteristics in pigs treated with iron at weaning as influenced by nursery diets supplemented with copper

Objective: Determine the effects of dietary copper on growth in pigs given iron at weaning. Materials and methods: Weanlings (n = 144) were allocated to a 2 × 2 × 2 factorial arrangement of treatments (6 pens/treatment, 3 pigs/pen). Factors were size (large or small), 100 mg intramuscular iron doses (birth or birth and weaning), and dietary copper (14.2 or 250 ppm). Average daily gain (ADG), feed intake (ADFI), and gain to feed ratio were determined for 49 days. Blood was sampled at weaning and days 7 and 49. Results: Hemoglobin (P &lt; .001) and hematocrit (P = .002) at weaning were less in large pigs. Pigs receiving two doses of iron had greater hemoglobin (P = .05) and hematocrit (P = .04). Hemoglobin (P = .03) and hematocrit (P = .03) were greater in pigs fed the control diet. In large pigs only, body weights at day 49 were greater (P = .05) for individuals receiving two doses of iron. The interaction between number of iron doses and diet affected many growth measures including ADG (P = .02) and ADFI (P = .04) for the overall trial. In all cases, performance was greater in copper-fed pigs receiving two doses of iron. Implications: At weaning, larger pigs had hematology characteristics consistent with a lower iron status. Iron treatment at weaning increased hemoglobin. Copper enhanced growth only if pigs received iron at weaning. In copper-fed pigs, hemoglobin was less, possibly indicating a negative effect on iron absorption.

Growth performance and hematology characteristics in pigs treated with iron at birth and weaning and fed a nursery diet supplemented with a pharmacological level of zinc oxide

Objective: To determine effects of an iron dose at weaning on growth and hematology in pigs fed zinc. Materials and methods: Weaned pigs (n = 144) were allocated to treatments in a 2 × 2 × 2 factorial arrangement (6 pens/treatment, 3 pigs/pen), with factors being pig size (large or small); number of 100 mg iron dextran doses (1 [birth] or 2 [birth and weaning]); and dietary zinc (100 or 2000 ppm). Average daily gain (ADG), feed intake (ADFI), and gain to feed ratio (G:F) were determined. Blood samples were collected at weaning and 7 and 49 days post-weaning. Results: Anemia (hemoglobin &lt; 9.0 g/dL) at weaning tended to be greater (P = .07) for large pigs and hemoglobin (P = .02) and hematocrit (P = .05) were greater in small pigs. Hematology was largely unaffected by number of iron doses or diet. Large pigs displayed greater ADG (P &lt; .001) but poorer G:F (P = .002). Zinc-supplemented pigs had greater (P = .002) ADG and G:F from day 0 to 21. From day 22 to 49, G:F (P = .005) was greater for controls. Overall, zinc tended to increase ADFI in large (P = .09) but not small (P = .46) pigs. Growth was largely unaffected by number of iron doses. Implications: Anemia at weaning was common, especially for larger pigs, but was not exacerbated by zinc. An iron dose at weaning had minimal effects on growth. Dietary zinc enhanced growth early post-weaning but effects waned as pigs aged.

PSVII-1 Growth performance from 65 to 125 kg body weight, and carcass and meat composition of gilts, barrows, immunologically castrated pigs and entire males.

The aim of this study was to evaluate growth performance, carcass and meat composition of T1) gilts, T2) barrows, T3) immunocastrated (IMC) and T4) entire male (EM) pigs. Twenty eight individually allocated Yorkshire-Landrace x Duroc-Pietrain pigs (68.8 ± 1.2 kg initial BW) were fed a sorghum-soybean meal-based diet (18.4% PC, 3.4 Mcal ME/kg), and water ad libitum. The IMC received two 2-mL subcutaneous injections of an antiGnRH immunological product (Improvac; Zoetis, Mexico) at 115 and 145 days of age. Body weight (BW), ADG, Feed Intake (ADFI), Feed efficiency (G:F) and hot carcass weight (HCW) were registered. Serum testosterone (TEST) was analyzed in blood samples taken at days 115, and 145 of age, and at slaughter, using a commercial ELISA kit (Mexlab, Mexico). Testicles and bulbourethral glands of IMC and EM pigs were weighed. Protein and fat contents were determined (AOAC, 2005) in Longissimus dorsi muscle (LM). Data were analyzed in a randomized block design with two blocks of contemporary pigs utilizing SPSS (v21), and means were compared with Tukey test (P < 0.05). ADFI was similar (P > 0.05) among treatments. Gilts had lower final BW (P < 0.05) than others (121.6 vs. 134.4 kg). IMC and EM had higher (P < 0.05) ADG (0.984 vs. 0.855 kg/d) and G:F (0.208 vs. 0.178 kg/kg) than gilts and barrows. TEST of gilts and barrows remained under 0.1 ng/mL (P < 0.05). At slaughter, IMC had less (P < 0.001) TEST (0.2 vs. 6.8 ng/mL), smaller testicles (0.276 vs. 0.702 kg; P < 0.002), and bulbourethral glands (0.075 vs. 0.202 kg; P < 0.002) than EM. Gilts had less HCW (P < 0.01) than others (99.6 vs. 109.7 kg). LM fat (2.80 ± 0.16%) and protein (22.6 ± 0.37%) content was similar (P > 0.05) among gender. In conclusion, immunologically castrated pigs had better ADG and G:F than barrows and gilts, however lower serum testosterone concentrations than EM pigs.

Effect of supplemental organic acids on performance, carcass characteristics, and serum biochemical metabolites in broilers fed diets containing different crude protein levels

The present study was conducted to investigate the effect of dietary supplementation of organic acids (OA) on performance and carcass characteristics of broiler chickens fed diets with different crude protein (CP) levels. A total of 540 day-old broiler chickens were assigned to 9 dietary treatments in a 3×3 factorial arrangement with 4 replicate pens and 15 broiler chickens per pen. Dietary treatments consisted of 3 different CP levels (high, medium, and low) and 3 dietary OA supplementation (control, 2.5g citric acid/kg, and 2.5g butyric acid/kg). Dietary CP levels in high-CP diets were 230, 210, and 190g/kg during starter, grower, and finisher periods, respectively. The respective values were 220, 200, and 180g/kg for medium-CP, and 210, 190, and 170g/kg for low-CP diets. The study lasted for 42 d. Performance variables including average daily gain (ADG), feed intake (ADFI), and feed conversion ratio (FCR) were measured biweekly. At the end of study, 2 randomly selected birds per pen were slaughtered to measure carcass traits. Furthermore, serum samples of 42-d-old broilers were analyzed for blood metabolites. Results showed that although ADFI and FCR values were not affected by CP levels, reducing dietary CP level (medium+low) decreased ADG during starter (P=0.092) and grower (P=0.053) periods. At the finisher phase, however, ADG was similar among different CP groups. Dietary supplementation of citric acid increased ADG (P=0.062) during starter period. In addition, OA supplementation of diets (citric+butyric) increased (P=0.002) ADG at the finisher period, resulting in improved (P=0.027) FCR values. Supplemental OA increased ADG only in broilers fed diets containing higher CP levels (high- and medium-CP diets), resulting in a CP×OA interaction (P=0.024) during the finisher period. The relative liver weight and carcass yield were decreased (P<0.05) by reducing dietary CP level (medium+low), while abdominal fat percentage was increased (P<0.001), with the greatest (P=0.004) abdominal fat allotted to broilers fed low-CP diet. Dietary OA supplementation (citric+butyric) increased (P=0.016) carcass yield, while reduced (P<0.001) relative gizzard weight. Although serum concentrations of high- and low-density lipoproteins and cholesterol were not affected by dietary CP level, feeding low-CP diet increased (P<0.001) serum triglyceride level compared with higher CP levels. Serum concentration of uric acid was decreased (P<0.001) as the result of reducing dietary CP level (medium+low). The present findings indicate that dietary CP level can be reduced by 2 percentage points if the most limiting amino acids are provided at the sufficient levels. On the other hand, dietary OA supplementation increased weight gain in the finisher period and carcass yield of broiler chickens.

Effect of mannan oligosaccharides (Bio-Mos) and outdoor access housing on pig growth, feed efficiency and carcass composition

The present study was conducted as a 3 × 2 factorial experiment in 7 pen replications conducted using progeny (n = 360) of successive farrowings of 1 Landrace breeding female population. Grower-finisher dietary treatments included the addition of Bio-Mos (BM; at 0.2, 0.1 and 0.05% inclusion rates for phase 1 (30.2 to 63.5 kg), 2 (63.5 to 90.5 kg), and 3 (90.5 to 113.6 kg), respectively), the inclusion of a subtherapeutic antibiotic (AB; tetracycline; at 0.0055% inclusion rate in all dietary phases) and a no additive control (CON) diet. Housing systems were a conventional, indoor (IN) facility providing 1.0 m(2)/pig solid concrete and 0.3 m(2)/pig slatted floor with 12 pigs per pen and an outdoor access (OUT) system providing 1.1 m(2)/pig indoor, bedded concrete, and 1.9 m(2)/pig outdoor solid concrete with 6 pigs per pen. Housing systems analyses acknowledge confounding of space with number of pigs per pen. Daily growth rate (ADG), feed intake (ADFI), feed conversion (G:F), ultrasonic carcass composition, blood hematocrit (1 group), and observed illnesses were measured. Dietary × housing treatment interactions were not observed. Pigs reared in OUT had greater ADFI (0.1 kg/d; P = 0.01) resulting in greater ADG (0.04 kg/d; P < 0.0005) and required fewer days to reach a standard 113.6 kg endpoint (4.0 d; P < 0.0005) but had reduced (poorer) G:F (0.01 kg gain/kg feed; P = 0.05) when compared to IN. Pigs fed BM and CON diets had greater ADG (0.02 kg/d; P < 0.05) and required 3 fewer days to 113.6 kg (P < 0.05) when compared with pigs fed AB. Carcass composition measures were not different across dietary or housing treatments. Hematocrit was 2 units greater (P < 0.05) at the end of the trial (d 84) for OUT housed pigs but not different at the start, d 28, or d 56 of the trial. In the present study, the addition of a subtherapeutic antibiotic in swine finisher diets did not improve pig growth, efficiency, or health whereas the addition of BM did not increase growth performance compared to the CON diet in both housing systems, a finding suggesting the potential for improved gut health and or improved appetite in pigs not fed an antibiotic. Whereas pigs reared OUT had greater growth rate and a more desirable hematocrit level, the observed differences may be attributed to stocking density, number of pigs per pen, or outdoor access, effects that are not able to be fully described under the experimental design.

Nutritional evaluation of dehulled faba bean (&lt;i&gt;Vicia faba&lt;/i&gt; cv. Fiord) in feeds for weaner pigs

The objective of this experiment was to determine whether faba bean could successfully be used in feeds for weaner pigs in the period 10 to 25 kg liveweight. An experiment was conducted using 48 weaner pigs (average weight 10 ± 0.42 kg) to determine the nutritive value of dehulled faba bean meal (Vicia faba cv. Fiord) in comparison with full-fat soy. Two basal feeds were formulated, the first containing no faba bean but with full-fat soy (FFS) as the protein source, while the second contained 300 g faba bean/kg feed (FB). These feeds were blended to produce a series of five feeds (T1 to T5) containing a range of faba bean contents. In addition, a choice feeding treatment was included in the experiment to determine whether pigs showed preferences for or against faba bean. The experimental feeds were: 1) 1.0 FFS; 2) 0.75 FFS + 0.25 FB; 3) 0.5 FFS + 0.5 FB; 4) 0.25 FFS + 0.75FB; 5) 1.0 FB and 6) choice between FFS and FB. Feeds were formulated to meet or exceed NRC (1998) nutrient requirements of weaner pigs. Diluting full-fat soya with dehulled faba bean meal had no effect on growth rate (ADG), feed intake (ADFI), feed conversion efficiency (FCE) or time taken to attain final weight. Male pigs had a numerically higher ADFI (1150 vs. 992 g/d) and ADG (553 vs. 539 g/d) than females, and reached the final liveweight on average 3 d before the females. When given a choice between the two basal feeds, no preference was shown for either feed. It may be concluded that a feed for weaner pigs may contain as much as 300 g dehulled faba bean/kg without causing any deleterious effects on performance as long as the quality of the faba beans is the same as that used in this trial.

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.

Influences of lipopolysaccharide-induced immune challenge on performance and whole-body protein turnover in weanling pigs

The objective of this study is to characterize the influence of immune stress induced by lipopolysaccharide (LPS) on protein utilization and turnover for early-weaned pigs. A total of 15, crossbred weanling pigs (initial body weight 10.15 ± 0.39 kg) were assigned to one of three treatments. Pigs were injected with LPS and fed ad libitum (LPS-challenge), or injected with endotoxin-free physiological salt solution (PSS) and fed ad libitum (control), or injected with PSS and fed the same amount of feed as LPS-challenged pigs (pair-feed). All pigs received a 4-d nitrogen balance trial. On d 1 and 3 of the trial, LPS-challenged pigs were injected intramuscularly with 200 μg/kg BW of LPS dissolved in 1 ml PSS. Pigs in other treatments were injected with 1 ml PSS. 15 N-Glycine (5 mg/kg BW) was gastrically infused after the second injection. Feces and urine were collected daily to determine the N output throughout the duration of the trial. Lymphocyte blastogenesis (LB) and serum immunoglobulins (IgA, IgG, IgM) were also detected to illustrate the LPS-induced immune responses. Results indicated that the injection of LPS significantly ( P < 0.01) elevated the LB and resulted in lower average daily gain (ADG), feed intake (ADFI) and efficiency of feed utilization than control pigs. Pair-fed pigs had higher performance than LPS-challenged pig but poorer than control pigs. Injection of LPS also resulted in significantly ( P < 0.01) lower nitrogen intake and efficiency of utilization than controls, and more fecal N excretion than Pair-fed pigs (3.19 ± 0.85 vs. 2.19 ± 0.67 g/d, P < 0.05). The whole-body nitrogen flux (4.34 ± 0.19 vs. 11.35 ± 0.12 g N/kg BW 0.75/d) and N accretion (5.57 ± 0.59 vs. 10.17 ± 1.12 g Pr/kg BW 0.75/d) were acutely ( P < 0.01) reduced as the feed intake decreased, but there was no significant difference between LPS-challenged and pair-fed pigs. Injection of LPS markedly ( P < 0.05) increased the protein degradation (16.76 ± 1.09 vs. 14.53 ± 1.24 g N/kg BW 0.75/d). It is concluded that LPS-induced immune challenge depresses growth performance and feed utilization efficiency by enhancing protein degradation rate and decreasing protein utilization for body protein retention.

The effect of virginiamycin in diets with adequate or reduced dietary calcium or nonphytate phosphorus for broilers

Four experiments (EXP) were conducted to evaluate the effects of virginiamycin (Vm) in diets adequate or reduced in Ca or nonphytate P (nPP) levels on growth performance and bone response variables in chicks. All diets were corn-soybean meal (C-SBM) based, and all treatments were replicated 6 or 8 times with 5 or 6 chicks each. In EXP 1 and 2, the dietary treatments were 1) C-SBM with 1.00% Ca and 0.45% nPP (positive control; PC); 2) C-SBM with 0.80% Ca and 0.45% nPP (0.80Ca); 3) C-SBM with 1.00% Ca and 0.35% nPP (0.35nPP); and 4 to 6) Diets 1 to 3 with 11 (EXP 1) or 22 (EXP 2) ppm of Vm. In EXP 1, daily gain (ADG), feed intake (ADFI), bone breaking strength (BBS), milligrams of ash per gram of Ca intake (ASH/Ca), and BBS per gram of Ca (BBS/Ca) or nPP (BBS/nPP) intake were increased in chicks fed Vm (P < 0.04 to 0.07). Chicks fed the 0.35nPP diet with Vm had increased ADG, ADFI, BBS, milligrams of tibia ash (ASH), BBS/Ca, and BBS/nPP (nPP x Vm, P < 0.03 to 0.10). Chicks fed the 0.80Ca diet with Vm had increased ASH, milligrams of ASH per gram of nPP intake (ASH/ nPP), and ASH/Ca (P < 0.01 to 0.09). Tibia ash, BBS, gain:feed (G:F), BBS/nPP, and ASH/nPP were decreased in chicks fed the 0.80Ca diet (P < 0.01 to 0.07). Bone ash percentage (BAP), BBS, BBS/Ca, ASH, and ASH/Ca were decreased in chicks fed the 0.35nPP diets (P < 0.01); ASH/ nPP was increased (P < 0.01). In EXP 2, BAP, ASH, ASH/ Ca, and ASH/nPP were increased in chicks fed Vm (P < 0.02 to 0.07). Chicks fed the 0.80Ca diet had a decreased ASH/nPP (P < 0.04) but an increased BBS/Ca and ASH/ Ca (P < 0.01 to 0.02). Chicks fed the 0.35nPP diet had decreased ADG, ADFI, G:F, BBS, BAP, ASH, ASH/Ca, and BBS/Ca (P < 0.01 to 0.04), but BBS/nPP and ASH/ nPP were increased (P < 0.01 to 0.04). In EXP 3, the dietary treatments were 1) PC; 2) C-SBM with 0.70% Ca and 0.45% nPP (0.70Ca); 3) C-SBM with 1.00% Ca and 0.25% nPP (0.25nPP); 4 to 6) Diets 1 to 3 with 9 ppm of Vm. The addition of Vm to the 0.25nPP diet decreased BBS (nPP x Vm, P < 0.06), but Vm increased BBS in the 0.70Ca and PC diets (P < 0.02). Chicks fed the 0.25nPP diet had decreased ADG, ADFI, and BBS (P < 0.01), and chicks fed the 0.70Ca diets had reduced ADFI, BBS, and G:F (P < 0.03 to 0.10). In EXP 4, 4 levels of nPP (0.15, 0.25, 0.35, or 0.45%) and 3 levels of Vm supplementation (0, 11, or 22 ppm) in a 4 x 3 factorial arrangement were used. The addition of Vm increased ADG, BBS, ASH, ASH/Ca, and ASH/nPP only in chicks fed diets with 0.35 or 0.45% nPP (nPP x Vm, P < 0.05). Daily gain, ADFI, G:F, BBS, BAP, BBS/Ca, and ASH were increased as nPP levels were increased (P < 0.01), but BBS/nPP and ASH/nPP were decreased (P < 0.01) as nPP levels were increased. The results obtained from these EXP indicate that Vm, regardless of supplementation level, can partially overcome an nPP deficiency when nPP levels are = 0.35%.

A comparison of two sources of phytase in liquid and dry forms in broilers

Research with corn-soybean meal diets was conducted to compare phytase sources in commercial broilers. A Ca to nonphytate P (nPP) ratio of 2.5:1 was maintained in all diets. Experiments 1 and 2 were conducted from d 4 to 13 (experiment 1) or d 9 to 23 post-hatching (experiment 2) in batteries. The 10 treatments used in both experiment were: Diets 1 to 4 = 0.20, 0.25, 0.30, or 0.35% nPP; Diets 5 to 7 = diet 1 plus 100, 200, or 300 phytase units/kg of diet from Natuphos (NAT); and Diets 8 to 10 = diet 1 plus 100, 200, or 300 phytase units/ kg of diet from Ronozyme (RON). As nPP levels increased, daily gain (ADG), feed intake (ADFI), gain:feed, and toe and tibia ash percentage were linearly increased (P < 0.06) in experiments 1 and 2. Incremental addition of phytase, regardless of source, linearly increased (P < 0.07) ADG and ADFI in experiment 1. Broilers fed NAT had higher (P < 0.07) toe ash percentage in experiment 1 and 2, and higher (P < 0.02) ADG and ADFI in experiment 2 than those fed RON. In experiment 3, 3,360 broilers were used to test 2 dry phytase products from 0 to 41 d posthatching in a 3-phase feeding program. The treatments were: Diet 1) adequate Ca and nPP; Diet 2) nPP reduced by 0.20%; Diets 3 to 5 = diet 2 plus 300, 500, or 750 phytase units/kg of diet from NAT; and Diets 6 to 8 = Diet 2 plus 300, 500, or 750 phytase units/kg of diet from RON. Broilers fed the adequate Ca and nPP diet had improved ADG and ADFI overall, and tibia ash weight and percentage in all growth phases (P < 0.03) compared with those fed the reduced Ca and nPP diets. Overall, ADG and ADFI were linearly increased (P < 0.05) by incremental phytase addition in experiment 3. Both NAT and RON produce similar growth and bone ash traits in commercial broilers.