Impact of Dietary Sodium Butyrate and Salinomycin on Performance and Intestinal Microbiota in a Broiler Gut Leakage Model

Unfavorable alterations of the commensal gut microbiota and dysbacteriosis is a major health problem in the poultry industry. Understanding how dietary intervention alters the microbial ecology of broiler chickens is important for prevention strategies. A trial was conducted with 672 Ross 308 day-old male broilers fed a basic diet (no additives, control) or the basic diet supplemented with 500 mg/kg encapsulated butyrate or 68 mg/kg salinomycin. Enteric challenge was induced by inclusion of 50 g/kg rye in a grower diet and oral gavage of a 10 times overdose of a vaccine against coccidiosis. Compared to control and butyrate-supplemented birds, salinomycin supplementation alleviated growth depression. Compared to butyrate and non-supplemented control, salinomycin increased potentially beneficial Ruminococcaceae and reduced potentially pathogenic Enterobacteriaceae and counts of Lactobacillus salivarius and Clostridium perfringens. Further, salinomycin supplementation was accompanied by a pH decrease and succinic acid increase in ceca, while coated butyrate (0.5 g/kg) showed no or limited effects. Salinomycin alleviated growth depression and maintained intestinal homeostasis in the challenged broilers, while butyrate in the tested concentration showed limited effects. Thus, further investigations are required to identify optimal dietary inclusion rates for butyrate used as alternative to ionophore coccidiostats in broiler production.

Fruit and Vegetable Supplemented Diet Modulates the Pig Transcriptome and Microbiome after a Two-Week Feeding Intervention

A study was conducted to determine the effects of a diet supplemented with fruits and vegetables (FV) on the host whole blood cell (WBC) transcriptome and the composition and function of the intestinal microbiome. Nine six-week-old pigs were fed a pig grower diet alone or supplemented with lyophilized FV equivalent to half the daily recommended amount prescribed for humans by the Dietary Guideline for Americans (DGA) for two weeks. Host transcriptome changes in the WBC were evaluated by RNA sequencing. Isolated DNA from the fecal microbiome was used for 16S rDNA taxonomic analysis and prediction of metabolomic function. Feeding an FV-supplemented diet to pigs induced differential expression of several genes associated with an increase in B-cell development and differentiation and the regulation of cellular movement, inflammatory response, and cell-to-cell signaling. Linear discriminant analysis effect size (LEfSe) in fecal microbiome samples showed differential increases in genera from Lachnospiraceae and Ruminococcaceae families within the order Clostridiales and Erysipelotrichaceae family with a predicted reduction in rgpE-glucosyltransferase protein associated with lipopolysaccharide biosynthesis in pigs fed the FV-supplemented diet. These results suggest that feeding an FV-supplemented diet for two weeks modulated markers of cellular inflammatory and immune function in the WBC transcriptome and the composition of the intestinal microbiome by increasing the abundance of bacterial taxa that have been associated with improved intestinal health.

PSV-16 Validation of an algorithm to assess feedbunk replacement events in beef cattle using an electronic feeding system

Visual observations of social behavior and dominance relationships in cattle have been used to examine associations with productivity and well-being. This method is time consuming limiting the number of animals that can be evaluated. The objective of this study was to validate an algorithm to quantify feedbunk replacement events using data from an electronic feeding system. Crossbred beef steers (n = 20) fed a grower diet were housed in 1 of 2 pens each equipped with 3 electronic feedbunks (GrowSafe Systems) and video recorders. A trained video observer recorded all feedbunk replacement events and other agonistic activities at the feedbunk over a 4-d period (24 h/d). The electronic feeding system recorded the start and end timestamps of bunk visit (BV) events for each animal. An algorithm was developed to determine BV events deemed to be replacement events, defined as a BV event when an actor animal displaced a reactor animal from the feedbunk and occupied the same feeder within a specified period of time (replacement criterion). We calculated the recall and precision corresponding to replacement criterions from 1 to 60 s, and the optimum replacement criterion was determined to be between 18 and 20 s. The recall, precision and F-score of the algorithm using this replacement criterion were high (on average > 0.75). Furthermore, a replacement competition index was computed as a proxy for competitive feedbunk behavior, calculated as the number of actor-initiated replacement events divided by the total number of replacement events for each steer. Using Spearmans rank correlation we found high correlations (r > 0.7; P < 0.05) between the electronic and observed indices. These preliminary results demonstrate the potential of the GrowSafe system to quantify feedbunk replacement events for confined beef cattle, providing opportunities to evaluate associations between competitive feedbunk behavior and economically relevant traits.

PSX-B-4 Effect of live yeast on the ruminal fermentation characteristics of growing steers in heat-stress conditions

The objective of this trial was to determine the influence of live yeast supplementation (LY) and temperature exposure (TEMP) on the ruminal fermentation characteristics of steers receiving a grower diet. The effects of LY and TEMP were investigated using a 2 x 2 crossover design that spanned five periods. Eight Angus crossbred steers (365 ± 32 kg) were randomly split into pairs and housed in four outdoor pens outfitted with an individualized feeding system. Animals were limit fed a grower diet (DIET) at 1.2% SBW with no live yeast supplementation (NOY) or a grower diet top-dressed with 10 g live yeast/d for 14 days (1.2 × 1012 CFU/d). On days 13 and 14, animals were subjected to one of two TEMP conditions, thermoneutral (TN; 18.4 ± 1.1°C, 57.6 ± 2.8 % RH) or heat stress (HS; 33.8 ± 0.6°C, 55.7 ± 2.7 % RH), in two side-by-side, single-stall open-circuit, indirect respiration calorimetry chambers. Data were analyzed using a random coefficients model. Carryover effects were examined and removed from the model if not significant (P > 0.05). There was no effect of DIET, TEMP, or DIET×TEMP (P > 0.05) on ruminal pH, redox, ciliated protozoa count, acetate, butyrate, total VFA, and ruminal ammonia concentrations. Similarly, the acetate to propionate ratio was not influenced by DIET, TEMP, or DIET × TEMP (P ≥ 0.190). Propionate concentration was the greatest in animals in TN conditions receiving LY (P = 0.008). Compared to HS+NOY, HS+LY (P = 0.003) and TN+LY (P = 0.043) had greater ruminal enumerations of Fusobacterium necrophorum. This suggests LY (P = 0.010) provided a favorable environment for F. necrophorum during heat stress. Live yeast supplementation did not improve overall ruminal fermentation during heat stress. Additional research is required to better understand the dynamic relationship between live yeast and temperature exposure.

288 Inclusion Effects of Quebracho (Schinopsis Balansaie) Extract and Active Dry Yeast (Saccharomyces Cerevisiae) in Beef Cattle Limit-fed a Grower Ration

Plant secondary metabolites (PSM) and yeast supplemented in growing cattle have been reported as improving dry matter digestibility (DMD) and reducing enteric methane emissions. This study aimed to evaluate the effect of combined supplementation with condensed tannin (CT; Schinopsis balansae) extract and active dry yeast (ADY; Saccharomyces cerevisiae) on fermentation dynamics, utilizing in vitro gas production (IVGP) technique. A 2 × 2 Latin square design was used to study fermentation patterns of four dietary treatments (CON- no CT and no ADY, ADY alone, CT alone or combined CT + ADY). Animals received daily CT at 1% DM and 10 g of ADY, respectively. On d 0, 7, 14, 21, 28, and 35 rumen inoculum was collected from 23 fistulated steers (284.3 ± 4.1 kg) four hours post-feeding. Samples were incubated under anaerobic conditions at 39oC for 48 h with 200 mg of a grower diet (14.8% CP, 40.6% NDF, 88.5% DM). Gas parameters were analyzed using a mixed linear statistical model. There was a day effect for total gas production (TGP; P < 0.001), non-fiber carbohydrate degradation (P = 0.031) and fractional degradation assuming an asymptote model (P = 0.015). Both asymptote and non-fiber fractional degradation rate estimates had an interaction between Day × TRT (P = 0.001 and 0.0104, respectively). Data were analyzed using polynomial contrasts showed a difference in non-fiber fractional rate of fermentation for CON × CT and CT × ADY (P = 0.052 and 0.054, respectively). This was also true if an asymptote model was assumed (P = 0.0 34 and 0.034, respectively). We concluded that combined supplementation of CT and ADY exhibited similar IVGP trends over time, this may be because animals only received a grower diet at 1.5% shrunk BW. Future studies should investigate the impact of combined supplementation on varying levels of concentrate diets.

Methionine Deficiency Affects Liver and Kidney Health, Oxidative Stress, and Ileum Mucosal Immunity in Broilers

Methionine (Met) is the first limiting amino acid in broiler diets, but its unclear physiological effects hamper its effective use in the poultry production industry. This study assessed the effect of a Met-deficient (MD) diet on chicken liver and kidney health, exploring the associated mechanisms of antioxidant capacity and ileum mucosal immunity. Seventy-two broilers were administered either the control diet (0.46% Met in starter diet, 0.36% Met in grower diet) or the MD diet (0.22% Met in starter diet, 0.24% Met in grower diet). Liver and kidney samples were collected every 14 days for anatomical, histological, and ultrastructural analyses, accompanied by oxidative stress assessment. Meanwhile, T- and B-lymphocyte abundance and essential cytokine gene expression were measured in the ileum, the center of the gut–liver–kidney axis. Signs of kidney and liver injury were observed morphologically in the MD group at 42 days of age. Furthermore, aspartate aminotransferase, alanine aminotransferase, creatinine, and uric acid levels were decreased in the MD group compared with the control group, accompanied by decreased superoxide dismutase activity, increased malondialdehyde content, decreased numbers of T and B lymphocytes, and decreased cytokine expression in the ileum, such as IL-2, IL-6, LITAF, and IFN-γ. These results suggest that MD can induce kidney and liver injury, and the injury pathway might be related to oxidative stress and intestinal immunosuppression.

The Effect of Green Tea (Camellia sinensis) Leaf Powder on Growth Performance, Selected Hematological Indices, Carcass Characteristics and Meat Quality Parameters of Jumbo Quail

Green tea leaves contain a wide range of active bio-compounds that are essential for sustainable quail intensification; however, its feed value is not known for the Jumbo quail. Therefore, this study evaluated the effect of different levels of green tea leaf powder (GTLP) on physiological and meat quality parameters of the Jumbo quail. One-week-old chicks (n = 350; 56.1 ± 2.12 g live-weight) were evenly distributed to 35 replicate pens and reared on five experimental diets formulated as follows: a standard grower diet with zinc-bacitracin (PosCon), a standard grower diet without zinc-bacitracin (NegCon), and NegCon diet treated with 10 (GT10), 25 (GT25) and 50 g/kg (GT50) of GTLP. Weight gain linearly decreased in week 2 but increased in week 4, whereas feed conversion efficiency linearly declined in weeks 2 and 3 as GTLP levels increased. Overall feed intake, carcass yield, and caecum and colon weights showed a linear increase with GTLP levels. Hematological parameters fell within the normal ranges reported for healthy quail. The GT10 group showed larger liver weights than the PosCon and NegCon groups. It was concluded that dietary inclusion of GTLP enhances overall feed intake and carcass performance but not feed efficiency, hematological and meat quality parameters of Jumbo quail.

Effect of high crude fibre feed towards digestive tract characteristics of crossbreed native chicken

This research was aimed to evaluate the use of high crude fibre feed on the characteristic of the native chicken digestive tracts. The research was conducted in Tembuku District, Bangli Regency in April-August 2020. There were four treatments starter diets included P0 (control), P1 (70% control feed+30% rice bran), P2 (70% control feed+30%+ Bio B 2cc/l drinking water), P3 (60% control feed+10% Indigofera meal+30% rice bran), while four treatment grower diet included P0 (25% control feed+35% rice bran+40% corn), P1 (15% control feed+35% rice bran+10% Indigofera meal+40% corn), P2 (15% control feed+35% rice bran+10% Indigofera meal+40% corn+2cc/l Bio-B), and P3 (22% control feed+31.5% rice bran+10% Indigofera meal+36.5% corn). The variables observed included final body weight, digestive tract weight, and digestive tract length. A factorial randomized block design was used in this study with univariate analysis and further Duncan test. This study showed that high crude fibre feed affected the digestive tract, such as the weight of the duodenum, jejunum, ileum, cecum, liver, pancreas, proventriculus. This also occurred in the parameters of the length of the duodenum, jejunum, ileum, cecum, and colon.

229 The effects of direct-fed microbial with and without monensin plus tylan on performance, feed efficiency and feeding behavior patterns in feedlot steers

Objectives of this study were to evaluate the effects of DFM with and without Monensin plus Tylan on feed efficiency and feeding behavior patterns in steers. Crossbred steers (n = 125; BW = 303 kg) were randomly assigned to 1 of 4 treatments in a 2 x 2 factorial design: (1) control (no feed additives), (2) DFM only (25 g/d; Natur’s Way), (3) Monensin (40 g/ton) plus Tylan only (MON) and (4) DFM and MON. In pens with GrowSafe feedbunks, steers were fed the grower diet for 14 d and transitioned to a finisher diet on 16 d. During the grower/transition phase, MON-fed steers had 9.5% higher (P < 0.05) ADG and improved F:G (7.8 vs 8.94; P = 0.06) and RFI (-0.28 vs 0.27 kg/d; P < 0.01) vs CON-fed steers. DFM-fed steers had lower (P < 0.01) ADG, but similar F:G and RFI than CON-fed steers. Daily variances of bunk-visit event frequencies were reduced (P < 0.01) in MON- vs CON-fed steers. During the finisher period, MON x DFM interactions (P < 0.10) were observed for ADG and F:G. MON-fed steers had numerically improved F:G (5%) when DFM was excluded, but not when DFM was included. MON-fed steers had lower RFI (P < 0.01; -0.23 vs 0.23 kg/d), whereas DFM-fed steers had higher RFI (P < 0.01) compared to respective controls. MON-fed steers ate less (P < 0.01) DMI, spent 9% more (P < 0.05) time consuming meals and had 14% slower (P < 0.01) meal eating rate then CON-fed steers. The DFM did not positively affect feed efficiency. Although the magnitude of improvement in feed efficiency due to MON was small, results demonstrated that MON may minimize digestive upsets by reducing daily variation in feeding behavior during diet transition and slow meal-eating rate on high-grain diets.

PSII-14 Effect of live yeast on greenhouse gas emissions and energy partitioning of growing steers in heat-stress conditions

The objective of this trial was to identify the influence of live yeast supplementation (LY) and temperature exposure (TEMP) on greenhouse gas emissions and energy metabolism of steers receiving a grower diet. The effects of LY and TEMP were investigated using a 2 × 2 crossover design that spanned five periods. Eight Angus crossbred steers (365 ± 32 kg; 41 mo) were randomly split into pairs and housed in four outdoor pens outfitted with an individualized feeding system. Animals were limit fed a grower diet (DIET) at 1.2% SBW with no live yeast supplementation (NOY) or a grower diet top-dressed with 10 g live yeast/d for 14 days (1.2 × 1012 CFU/d). On days 13 and 14, animals were subjected to one of two TEMP conditions, thermoneutral (TN; 18.4 ± 1.1°C, 57.6 ± 2.8 % RH) or heat stress (HS; 33.8 ± 0.6°C, 55.7 ± 2.7 % RH), in two side-by-side, single-stall open-circuit, indirect respiration calorimetry chambers. Data were analyzed using a random coefficients model. Carryover effects were examined and removed from the model if not significant (P > 0.05). There was no effect of DIET, TEMP, or DIET × TEMP (P ≥ 0.752) on enteric methane or carbon dioxide emissions. Similarly, GE, ME, DE, and RE were not influenced by DIET, TEMP, or DIET × TEMP (P ≥ 0.152). Gaseous energy, as a percentage of GE, tended to increase during HS (P = 0.097). Heat energy, as a percentage of GE, had a significant LY carryover effect (P = 0.045), with HS×NOY resulting in less HE than TN×NOY (P = .0495) and HS×LY (P = .084). Live yeast supplementation did not reduce enteric emissions, nor did it improve energy metabolism during heat stress. Further research is required to better understand the dynamic relationship between live yeast and temperature exposure.