Effect of pelleting on nutrients and energy digestibility in growing pigs fed corn-soybean meal-based diet or diet containing corn distillers dried grains with solubles (cDDGS), wheat middlings and bakery meal

This study was conducted to determine the effect of pelleting and diet type on the apparent ileal (AID) and total tract digestibility (ATTD) of nutrients and energy in growing pigs. Six pigs were cannulated at the ileum and were assigned to treatments following a crossover design. One diet was a control diet based of corn and soybean meal (CT). Part of it was replaced by corn distillers dried grains with solubles (cDDGS), wheat middlings and bakery meal in the second diet (ByP). Diets were in mash (CT-MH and ByP-MH) or pelleted (CT-PT and ByP-PT) form. Results showed that pelleting increased digestibility in all diets with a distinct effect on the CT diet (interaction Diet x Pelleting, P < 0.05). Pelleting improved the AID of DM, CP and energy by 17, 27 and 17% in the CT diet and by 10, 9 and 17% in the ByP diet (P < 0.01). The AID of AA followed the effect observed on CP (P < 0.01). Pelleting increased AID of total NSP for the CT diet by 63% and 42% for the ByP diet (P < 0.01). The pelleting conditions improved the degradability of the compounds in the diets during digestion in pigs.

Social Status Differentially Affects Behavioral and Immunological Outcomes of Group-Kept Sows Fed Different Dietary Fiber Using Different Length Feeding Barriers

Social conflict is inevitable among group-housed sows and may contribute to poorer welfare among those sows experiencing more social stress. The degree of individual welfare is associated with social position within the group. Therefore, this study examined the effects of social status on behavior, immune, endocrine, and productivity of group-housed pregnant sows fed a diet supplemented with 30% wheat middlings and 15% soybean hulls (MID-SH) or 30% distillers dried grains with solubles and 30% corn germ meal (DDGS-GM) and in pens with individual feeding places made from short (58.4 cm) or long (203.2 cm) barriers. A 2 × 2 factorial design resulted in 4 experimental treatment groups (n = 9 sows/diet-length-block combination): (1) MID-SHshort; (2) MID-SHlong; (3) DDGS-GMshort; (4) DDGS-GMlong. Groups of sows equally representing all diet-length combinations across 4 blocks (n = 36 sows/block) were subjected to a feeding competition test to identify highest (dominant) and lowest (subordinate) ranked sows within each group resulting in 64 sows (n = 16 sows/treatment; n = 32 sows/social status). Data revealed 2- and 3-way interactive effects on aggressive behavior (P &lt; 0.005), postural (P &lt; 0.01), oral (P &lt; 0.0001), and eating (P &lt; 0.005) behaviors, sow mean body weights and gains (P &lt; 0.05) and litter weaning weights (P &lt; 0.05), especially among subordinates in pens with long barriers. Subordinates in pens with long barriers received 21% less aggression and were 73% less likely to be displaced than subordinates in pens with short ones (P &lt; 0.0001). Dietary treatment also influenced some of these measures among the subordinates in pens with long barriers. For example, subordinates in DDGS-GMlong received 64 and 67% less aggression than subordinates in DDGS-GMshort and MID-SHshort (P &lt; 0.005). Eat bouts were greatest among subordinates in MID-SHlong, and sitting and sham-chewing were less. However, those in DDGS-GMlong spent less time standing and laying, and their litters were 15.28 kg heavier (P = 0.01), but overall subordinates fed DDGS-GM diet were lightest and gained less total body weight than those fed MID-SH (P &lt; 0.05). Other measures such as neutrophil-to-lymphocyte ratio were elevated among dominants in MID-SHlong (P &lt; 0.05); whereas, cortisol (P = 0.06) was lowest and glucose (P = 0.09) highest for subordinates in DDGS-GMlong. These data imply that subordinates benefited from being housed in pens with long barriers, but the type of dietary fiber consumed differentially influenced behavioral budget and several sow- or litter-related traits among subordinates in pens with long barriers. In contrast, the subordinates in pens with short barriers had poorer welfare regardless of diet. Collectively, these data imply that social status is a crucial factor contributing to variation in individual well-being among group-housed sows and that sows of different social positions within a group may evoke different biological responses in an attempt to cope.

Effects of Lactobacillus reuteri and Streptomyces coelicolor on Growth Performance of Broiler Chickens

There are well documented complications associated with the continuous use of antibiotics in the poultry industry. Over the past few decades, probiotics have emerged as viable alternatives to antibiotics; however, most of these candidate probiotic microorganisms have not been fully evaluated for their effectiveness as potential probiotics for poultry. Recent evaluation of a metagenome of broiler chickens in our laboratory revealed a prevalence of Lactobacillus reuteri (L. reuteri) and Actinobacteria class of bacteria in their gastrointestinal tract. In this study Lactobacillus reuteri and Streptomyces coelicolor (S. coelicolor) were selected as probiotic bacteria, encapsulated, and added into broiler feed at a concentration of 100 mg/kg of feed. In an 8-week study, 240 one day-old chicks were randomly assigned to four dietary treatments. Three dietary treatments contained two probiotic bacteria in three different proportions (L. reuteri and S. coelicolor individually at 100 ppm, and mixture of L. reuteri and S. coelicolor at 50 ppm each). The fourth treatment had no probiotic bacteria and it functioned as the control diet. L. reuteri and S. coelicolor were added to the feed by using wheat middlings as a carrier at a concentration of 100 ppm (100 mg/kg). Chickens fed diets containing L. reuteri and S. coelicolor mixture showed 2% improvement in body weight gain, 7% decrease in feed consumption, and 6–7% decrease in feed conversion ratios. This research suggests that L. reuteri and S. coelicolor have the potential to constitute probiotics in chickens combined or separately, depending on the desired selection of performance index.

249 Increasing Structural Fiber Improves Growth Performance of Nursery Pigs

Fiber ingredients in swine diets have various components that affect the intestinal tract distinctively. The objective of this study was to determine the effect of structural fiber sources on growth performance of nursery pigs. A total of 1,760 weanling pigs (initial BW = 6.12 ± 0.3 kg, 16 reps/trt, 22 pigs/pen) were used in a study with 5 dietary treatments: 1) Complex nursery diet with no additional fiber (CON); 2) CON + 2% rice hulls; 3) CON + 4% rice hulls; 4) CON + 6% wheat middlings; 5) CON + 12% wheat middlings. Fiber ingredients were added at the expense of corn and some processed soybean meal to maintain similar dietary protein levels. Using an in vitro fermentation estimation of fermentation for rice hulls and wheat middlings, diets were constructed to add similar levels of structural (non-fermentable NDF) fiber between low and high additions of rice hulls and wheat middlings. Pens across two barns were randomly allotted independent of one another and within a location block to one of the five treatments on d 0 of a two-phase study (d 0–11 and d 11–20.5 post-weaning). Data were analyzed by general linear model in R. Mortality and removal data were analyzed as a generalized linear mixed model with a binomial distribution. Contrasts tested the effect of additional fiber (CON vs treatments 2–5), effect of medium vs high fiber (treatment 2/4 vs 3/5), effect of source of fiber (treatment 2/3 vs 4/5), and the interaction of level and source of fiber. Overall (Table 1), additional fiber resulted in increased ADFI (P &lt; 0.05) and tended to increase ADG (P &lt; 0.10). Probability of mortality and removal was reduced (P &lt; 0.05) when additional fiber was included. In summary, increasing the level of structural fiber improved performance and livability of nursery pigs.

PSII-23 Addition of Hydrogen Chloride to Collection Bags or Containers Did Not Change Basal Endogenous Losses or Digestibility of Amino Acid in Corn, Soybean Meal, or Wheat Middlings Fed to Growing Pigs

The hypothesis that apparent ileal digestibility (AID), basal endogenous losses, and standardized ileal digestibility (SID) of AA are not affected by adding acid to collection containers or bags used to collect ileal digesta from pigs was tested. Twenty-four barrows (initial BW: 77.8 kg) that had a T-cannula installed in the distal ileum were fed diets for three 7-d periods. Corn, soybean meal, and wheat middlings were the sole AA sources in each diet and an N-free diet was also used. Within each period, each of the 4 diets was fed to 6 pigs. Among the 6 pigs, digesta from 3 pigs were collected in bags containing no HCl, whereas 40 mL of 3N HCl was included in the bags used to collect digesta from the remaining 3 pigs. Every other bag collected from each pig was emptied into a container without adding HCl, whereas the remaining bags were added to a container along with 40 mL of 3N HCl for each bag. All digesta were stored at –20 °C immediately after collection. Data were first analyzed using a model that included feed ingredient, HCl in bags, HCl in containers, and all 2-way and 3-way interactions as fixed effects. No 3-way interactions were significant, and data were, therefore, analyzed independently for each diet as a 2 × 2 factorial. Results indicated that there were no interactions between adding HCl to collection bags and to containers, and no effects of adding HCl to collection bags or containers for AID, basal endogenous losses, or SID of most AA were observed (Table 1). In conclusion, if digesta are stored at –20 °C immediately after collection, it is not necessary to add acid to digesta collection bags or collection containers.

Impact of Sow Transition Diet and Genetic Line on Sow Reproduction Under Heat Stress Conditions

The objective was to evaluate a sow transition diet and genetic line for farrowing duration and sow lactation characteristics. One batch of second parity sows (n = 78) were farrowed at the NCDA Tidewater Research Station in July. Sows consisted of two genetic lines, one selected since 2012 for young age at puberty and the other selected for old age at puberty. From day 109 of gestation until day 3 of lactation, sows were fed either 2.73 kg of a corn-soy lactation diet (3322 Kcal ME/kg, 0.99% SID lysine) once per day or 1.36 kg twice per day of a transition diet (3489 Kcal/kg, 0.71 SID lysine). The transition diet contained 45% wheat middlings, 8% added soybean oil, 3000 FTU/kg of phytase and 500 ppm zinc sulfate. Continuous traits and categorical traits were analyzed in SAS using linear models and chi-square tests, respectively. Results showed sows fed the transition diet farrowed numerically faster (P = 0.18) than those receiving the lactation diet (3:04 vs. 3:47). Transition diet fed sows tended (P = 0.10) to have a shorter wean-to-estrus interval than sows fed the lactation diet (5.27 vs. 5.69 days). Sows from the young puberty genetic line tended (P = 0.07) to have a greater average daily feed intake during lactation when compared to old puberty line females (4.92 vs. 4.71 kg). Young puberty sows also had a greater (P = 0.03) percentage of females exhibiting estrus by day 7 after weaning when compared to the old puberty genetic line (80 vs. 57%). No differences (P = 0.39 to 0.87) were detected between diets or genetic lines for stillborn piglet percentage, average piglet birth weight, average piglet weaning weight or litter size at weaning. Results suggest young puberty sows are more likely to return to estrus under the conditions of this study.

Dietary Fiber Source and Length of Feeding Partitions Differentially Affected Behavior, Immune Status, and Productivity of Group-Housed Dry Sows

Aggression is one of the major welfare concerns among group-housed sows, especially during feeding and regrouping. There are no simple solutions, but any attempt to reduce aggression should be considered. Therefore, the aim was to reduce aggression among group-housed gestating sows by feeding sows different dietary fiber using individual feeding places made from either short- or long-length partitions. Five blocks (n = 36 sows/block) of primiparous and multiparous sows were fed a dietary treatment of either 30% wheat middlings and 15% soybean hulls (MIDD-SY) or 30% distillers dried grains and 30% corn germ meal (DDGS-GM) and housed in pens (9 sows/pen) with individual feeding partitions that were either shoulder (short) or full-body (long) in length. Sow behavior, skin lesions, immune status, and performance were measured. Sow behavior, including aggression and lesion severity scores, were mainly affected by partition length. Aggressive encounters were greater and remained elevated among sows in pens with short partitions until 9 weeks post-grouping but were reduced among sows in pens with long partitions by 3 weeks. During feeding, sows in pens with short ones were more likely to be displaced than were those in pens with long ones. Percentages of time spent lying, standing, eating, and oral–nasal–facial behaviors were also differentially influenced by partition length. Dietary fiber differentially influenced immune status and productivity. For example, sows fed MIDD-SY had higher lymphocyte proliferation and increased neutrophils, while those fed DDGS-GM had deeper backfat and weaned heavier piglets. Overall, the length of the feeding partitions influenced the aggressive encounters, other behaviors, and lesion scores; in turn, the fibrous source differentially influenced several immune measures and sow productivity.

181 Effects of Aspergillus oryzae prebiotic on energy and nutrient digestibility of growing pigs

The objective of this study was to determine the effects of an Aspergillus oryzae prebiotic (AOP, Amaferm®) on nutrient digestibility in growing pigs fed high fiber diets. Eighteen growing barrows (initial BW = 50.60 ± 4.90 kg) were surgically equipped with a T-cannula at the distal ileum. Three diets were formulated by including 29.65% corn-distillers dried grains with solubles (DDGS), 36.65% rice bran (RB) or 24.59% wheat middlings (WM) in corn and soybean meal-based diets to meet nutrient requirements for 50 to 75 kg growing pigs. Three additional diets were formulated by supplementing 0.05% AOP at the expense of corn in DDGS (DDGS + AOP), RB (RB + AOP), and wheat middlings (WM + AOP) diets. Pigs were allotted randomly to a triplicated 6 × 2 Youden square design with 6 diets and 2 successive periods. Feces and ileal digesta were collected for 2 d after a 21 d adaptation period, and nutrient content was analyzed to calculate apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID). Standardized ileal digestibility (SID) of amino acids was calculated by correcting AID with basal endogenous amino acid losses determined from the same set of pigs. Supplementation of 0.05% AOP increased (P &lt; 0.05) ATTD of DM, GE, CP, NDF, and ash in DDGS, RB, and WM diets. Diet DE was 35 kcal/kg greater (P &lt; 0.05) in pigs fed AOP supplemented diets compared with those fed diets without AOP. Pigs fed DDGS+AOP diet had greater (P &lt; 0.05) AID of ether extract compared to those fed DDGS diet. However, supplementation of AOP did not (P &gt; 0.05) affect AID of GE, DM, CP, NDF, ash or SID of amino acids. In conclusion, supplementation of AOP in high fiber diets containing DDGS, RB, or WM increased total tract energy value and nutrient digestibility.