Short-chain fatty acid administration via water acidifier improves feed efficiency and modulates fecal microbiota in weaned piglets.

This study examined the effect of a water acidifier containing free and buffered short-chain fatty acids (SCFA-WA) on growth performance and microbiota of weaned piglets. In total, 192 male piglets, approximately 4 wk of age, were allocated to 24 pens (12 per treatment) with 8 piglets per pen. The piglets received either regular drinking water (negative control) or drinking water with the acidifier supplied at 2 L/1,000 L. Body weight and feed intake were measured weekly on pen level. During the first 2 wk, daily visual assessment and scoring of the feces was conducted. Fecal samples of three piglets per pen were collected on days 14 and 42 for high-throughput sequencing analysis of the microbiota. Piglets offered SCFA-WA had significantly improved feed efficiency in the third week (P = 0.025) and over the whole study period (days 0 to 42, P = 0.042) compared with piglets in the negative control group, with a strong tendency observed during the first feeding phase (days 0 to 21, P = 0.055). Furthermore, the water acidifier group had a higher water intake than piglets provided with control water during the second feeding phase (days 21 to 42, P = 0.028) and over the whole study period (days 0 to 42, P = 0.043). There was no significant difference in body weight, average daily gain, or average daily feed intake (days 0 to 21, 21 to 42, 0 to 42). Furthermore, there was no overall significant difference in fecal scoring between the treatments. In terms of the fecal microbiota response, piglets offered the water acidifier showed a significantly higher relative abundance (RA) of genus Clostridium sensu stricto 1 and a lower RA of genus Streptococcus compared to the control. Furthermore, the redundancy analysis showed a positive association between improved feed efficiency and daily weight gain and RA of Butyricicoccus and Faecalibacterium. In conclusion, consumption of the water acidifier containing free and buffered SCFA modulated the microbiota and improved feed efficiency in piglets.

Efficacy of a Synergistic Blend of Organic Acids and ß-1,4 Mannobiose on Cecal Salmonella Counts and Growth Performance in Salmonella Challenged Broiler Chickens: A Meta-Analysis.

This study aimed at investigating the effect of a functional synergistic feed additive blend, containing organic acids and ß-1,4 mannobiose, on cecal Salmonella counts and growth performance of broiler chickens. A meta-analysis combining 13 individual studies, executed in Salmonella-challenged broilers comparing a control diet with and without the synergistic blend, was performed. Cecal Salmonella colonies and overall growth performance were measured. Raw data from all studies were combined and analyzed using PROC MIXED in SAS, taking the within and between-study variation into account. In the first 14 days post-inoculation (DPI), cecal Salmonella was reduced by 0.429 log CFU/g (p = 0.011, n = 10 comparisons from five studies) when feeding the synergistic blend compared to the control group. During 15-34 DPI, the overall means were not different between treatments (0.069 log CFU/g; p = 0.519, n = 12 comparisons from eight studies). The feed conversion ratio was improved when feeding the synergistic blend compared to the control diet (1.474 vs. 1.482, respectively; p = 0.002). In conclusion, feeding a synergistic blend, containing organic acids and ß-1,4 mannobiose amongst other ingredients, reduced cecal Salmonella counts during the first 14 DPI and improved growth performance of Salmonella challenged broilers compared to a control diet.

Hydroxychloride trace minerals have a positive effect on growth performance, carcass quality and impact ileal and cecal microbiota in broiler chickens.

BACKGROUND: The objective was to study the effect of hydroxychloride trace minerals (HTM) on growth performance, carcass quality and gut microbiota of broiler chickens in comparison to sulphate trace minerals (STM). In total 1440 male Ross 308 day-old chicks were divided into 12 replicate pens with 30 birds each per treatment. Four different treatments were tested according to a 2 × 2 factorial study design, where the animals received a three phase diet containing either inorganic Zn from sulphates or Zn from HTM in high (80 mg/kg Zn) or low Zn dosage (20 mg/kg Zn). In all treatments 15 mg/kg Cu was added from the same mineral source as the Zn. Body weight and feed intake were measured on day 0, 10, 27 and 34, while carcass and breast meat yields were measured at the end of the study (day 34). In addition, high-throughput sequencing analysis was performed in digesta samples from ileum and cecum to study the gut microbiome (day 34). RESULTS: The results showed an improved (P < 0.05) body weight of broiler chickens fed HTM, regardless of Zn level, on day 27, while on day 34 this effect remained as a tendency (P = 0.0542). In the overall study period, birds fed HTM had a higher (P < 0.05) average daily gain and average daily feed intake when compared to birds fed STM. The mineral source did not affect the carcass characteristics, however, feeding 80 mg/kg Zn resulted in a significantly higher (P = 0.0171) breast meat yield, regardless of source. High-throughput sequencing analysis of the microbiota revealed a higher microbial diversity in the ileum and cecum of HTM fed birds compared to STM fed birds. Taxonomical differences were mainly found in the cecum, specifically between the group fed high and low Zn levels from HTM. This correlated with the mineral contents observed in the cecal digesta. Comparing both groups fed 80 mg/kg Zn, the HTM group had more Streptococcaceae, Streptococcus, Clostridia, Weissella and Leuconostocaceae compared to the STM group. CONCLUSIONS: HTM improved growth performance of broiler chickens; and the source and level of Zn modulated the gut microbiota communities in broilers differentially.

The effect of hydroxychloride trace minerals on the growth performance and carcass quality of grower/finisher pigs: a meta-analysis.

The current study compared the effect of hydroxychloride trace minerals (HTM) with the effect of inorganic trace minerals (ITM) on growth performance and carcass quality in grower-finisher pigs. The results of 6 studies conducted throughout Europe were combined into one meta-analysis. All included studies were performed using pigs from about 19 kg of body weight until slaughter. In all studies, 2 different mineral sources were compared, HTM and sulfates as ITM. Zn from either HTM or ITM was added at a level of 80 ppm to the diet, and Cu was added at a level of 15 ppm from the same source as Zn. In most studies, an additional treatment was included in which 20 ppm Zn was used from either source in combination with 15 ppm Cu from the same source. Diets were fed in 3 phases according to local commercial standards. The body weight, average daily gain, average daily feed intake, and gain:feed ratio were measured at the end of each phase. At the end of each study, the carcass yield, back fat thickness, and lean meat percentage were measured at commercial slaughterhouses. The meta-analysis was conducted using a MIXED model in SAS taking into account the within-study and between-study variation. The comparison was done only between HTM and ITM added at the same Zn level. No statistical differences were observed for growth performance or carcass characteristics between the mineral sources in pigs fed 20 ppm Zn. When 80 ppm Zn was used, a significant improvement in lean meat percentage was observed in pigs fed HTM compared with pigs fed ITM. In the overall study period, there was a tendency towards an increased gain:feed ratio in pigs fed 80 ppm Zn from HTM. In the last feeding phase, before slaughter gain:feed ratio and average daily gain were both significantly improved by 3.9%. In conclusion, HTM addition improved growth performance and lean meat percentage in grower-finisher pigs.

Sulfate and hydroxychloride trace minerals in poultry diets - comparative effects on egg production and quality in laying hens, and growth performance and oxidative stress response in broilers.

Two experiments investigated the effect of sulfate and hydroxychloride trace minerals (TM), Zn, Cu, and Mn, in laying hens and broiler chickens. In Expt. 1, Lohmann Brown pullets (total of 1,344) at 21 wk of age were used for a 24-wk experiment. Each of the two treatments had 32 replicates with 21 hens per replicate. At 45 wk of age, three eggs per cage were randomly selected and used for internal quality assessment. In Expt. 2, Ross 308 broilers (total of 1,080) were allocated to two treatments. Each treatment had 30 replicates with 15 chicks per replicate. On day 28, after weighing, three birds were randomly selected from 15 randomly selected pens per treatment. The birds were euthanized and blood was collected for analysis for uric acid, C-reactive protein and methylmalonic acid. Samples were also taken from pectoralis muscle of each chicken and analyzed for mRNA expression of protein synthesis or hydrolysis genes. On day 35, 7 birds per pen were used for carcass evaluation. In Expt. 1, egg weight was greater (P < 0.01) in birds receiving sulfate TM from week 16 (of experiment) onwards whereas the percentage of cracked eggs was lower (P < 0.01) in hens receiving hydroxychloride TM. Percentage hen-day production tended to be greater (P < 0.10) in hens receiving hydroxychloride TM in weeks 4 to 8 only. In Expt. 2, birds receiving hydroxychloride TM had greater (P < 0.05) weight gain and tended to have greater (P < 0.10) feed intake on day 35. Expression of the gene, PSMA1, was lower (P < 0.05) whereas plasma level of uric acid and methyl malonic acid tended to be lower (P < 0.10) in birds receiving hydroxychloride TM. It was concluded that hydroxychloride TM reduced egg loss in hens at peak production and that improved growth performance response in broilers can be partly explained by reduction in proteolytic activities in the pectoralis muscle and greater resilience to oxidative stress.

Weaned piglets prefer feed with hydroxychloride trace minerals to feed with sulfate minerals.

The aim of this study was to determine whether newly weaned piglets had a preference for diets containing hydroxychloride trace minerals (HTM). To test this, two preference tests were set up. In Exp. 1, the piglets could choose between HTM or inorganic, originating from sulfate trace minerals (STM) in the form of sulfates. Two treatments were applied with high Cu levels (160 ppm Cu added) or low Cu levels (15 ppm Cu added). All diets contained 110 ppm added Zn from the same source as Cu in the respective diet. The pigs could choose between a diet with hydroxychloride Cu and Zn or with Cu and Zn originating from sulfates at the same mineral levels. The piglets were included in the study from weaning until 34 d after weaning. In Exp. 2, the piglets could also choose between HTM and STM. However, automated feeding stations were used to collect individual feed intake data. Similarly two treatments were applied, one with high Cu levels (160 ppm added Cu) and one with slightly lower Cu levels (140 ppm added Cu until 28 d after weaning, thereafter 15 ppm added Cu). All diets contained 110 ppm added Zn from the same source as Cu in the respective diet. The piglets were followed until 35 d after weaning. The current studies showed that when piglets were given a choice, they preferred diets with HTM. This effect resulted only in a significant (P < 0.05) preference for HTM at high dietary Cu levels (160 ppm) ranging from 76% to 81% in the first and second week of Exp. 1 to between 53.4% and 57.8% in the overall experiment period of Exp. 2. This preference was less pronounced at levels of 140 ppm added or less. Individual feed intake and gain measurements did not show any link between the preference and the performance.

Selective ligninolysis of wheat straw and wood chips by the white-rot fungus Lentinula edodes and its influence on in vitro rumen degradability.

BACKGROUND: The present work investigated the influence of lignin content and composition in the fungal treatment of lignocellulosic biomass in order to improve rumen degradability. Wheat straw and wood chips, differing in lignin composition, were treated with Lentinula edodes for 0, 2, 4, 8 and 12 wk and the changes occurring during fungal degradation were analyzed using pyrolysis-gas chromatography-mass spectrometry and detergent fiber analysis. RESULTS: L. edodes preferentially degraded lignin, with only limited cellulose degradation, in wheat straw and wood chips, leaving a substrate enriched in cellulose. Syringyl (S)-lignin units were preferentially degraded than guaiacyl (G)-lignin units, resulting in a decreased S/G ratio. A decreasing S/G ratio (wheat straw: r = -0.72, wood chips: r = -0.75) and selective lignin degradation (wheat straw: r = -0.69, wood chips: r = -0.88) were correlated with in vitro gas production (IVGP), a good indicator for rumen degradability. CONCLUSIONS: L. edodes treatment increased the IVGP of wheat straw and wood chips. Effects on IVGP were similar for wheat straw and wood chips indicating that lignin content and 3D-structure of cell walls influence in vitro rumen degradability more than lignin composition.

The effect of particle size and amount of inoculum on fungal treatment of wheat straw and wood chips.

BACKGROUND: The aim of this study was to optimize the fungal treatment of lignocellulosic biomass by stimulating the colonization. Wheat straw and wood chips were treated with Ceriporiopsis subvermispora and Lentinula edodes with various amounts of colonized millet grains (0.5, 1.5 or 3.0 % per g of wet weight of substrate) added to the substrates. Also, wheat straw and wood chips were chopped to either 0.5 or 2 cm. Effectiveness of the fungal treatment after 0, 2, 4, 6, or 8 wk of incubation was determined by changes in chemical composition, in vitro gas production (IVGP) as a measure for rumen degradability, and ergosterol content as a measure of fungal biomass. RESULTS: Incomplete colonization was observed for C. subvermispora treated wheat straw and L. edodes treated wood chips. The different particle sizes and amounts of inoculum tested, had no significant effects on the chemical composition and the IVGP of C. subvermispora treated wood chips. Particle size did influence L. edodes treatment of wheat straw. The L. edodes treatment of 2 cm wheat straw resulted in a more selective delignification and a higher IVGP than the smaller particles. Addition of 1.5 % or 3 % L. edodes inoculum to wheat straw resulted in more selective delignification and a higher IVGP than addition of 0.5 % inoculum. CONCLUSION: Particle size and amount of inoculum did not have an effect on C. subvermispora treatment of wood chips. At least 1.5 % L. edodes colonized millet grains should be added to 2 cm wheat straw to result in an increased IVGP and acid detergent lignin (ADL) degradation.

Bioassay based screening of steroid derivatives in animal feed and supplements.

Receptor binding transcription activation bioassays are valuable tools for the screening of steroid hormones in animal feed and supplements. However, steroid derivatives often lack affinity for their cognate receptor and do not show any direct hormonal activity by themselves. These compounds are thus not detected by these kinds of bioassays and need a bioactivation step in order to become active, both in vivo and in vitro. In this study a comparison was made between different in vitro activation methods for hormone esters and hormone glycosides. Testosterone acetate and testosterone decanoate were chosen as model compounds for the hormone esters, representing the broad range of steroid esters of varying polarities, while genistin was used as a substitute model for the steroid-glycosides. Concerning bioactivation of the steroids esters, the efficiency for alkaline hydrolysis was 90-100% and much better as compared to enzymatic deconjugation by esterase. As a result 1 µg testosterone ester per gram of animal feed could easily be detected by a yeast androgen bioassay. When comparing different enzyme fractions for deglycosilation, genistin was shown to be deconjugated most efficiently by ß-glucuronidase/aryl sulfatase from Helix pomatia, resulting in a significant increase of estrogenic activity as determined by a yeast estrogen bioassay. In conclusion, chemical and enzymatic deconjugation procedures for ester and glycoside conjugates respectively, resulted in a significant increase in hormonal activity as shown by the bioassay readouts and allowed effective screening of these derivatives in animal feed and feed supplements.