Effect of crude protein concentration and sugar-beet pulp on nutrient digestibility, nitrogen excretion, intestinal fermentation and manure ammonia and odour emissions from finisher pigs

A 2 × 2 factorial experiment was conducted to investigate the interaction between high and low dietary crude protein (CP) (200 v. 150 g/kg) and sugar-beet pulp (SBP) (200 v. 0 g/kg) on nutrient digestibility, nitrogen (N) excretion, intestinal fermentation and manure ammonia and odour emissions from 24 boars (n = 6, 74.0 kg live weight). The diets were formulated to contain similar concentrations of digestible energy (13.6 MJ/kg) and lysine (10.0 g/kg). Pigs offered SBP-containing diets had a reduced (P < 0.05) digestibility of dry matter, ash, N, gross energy and an increased (P < 0.001) digestibility of neutral-detergent fibre compared with pigs offered diets containing no SBP. There was an interaction between CP and SBP on urinary N excretion and the urine : faeces N ratio. Pigs offered the 200 g/kg CP SBP-based diet had reduced urine : faeces N ratio (P < 0.05) and urinary N excretion (P < 0.05) compared with those offered the 200 g/kg CP diet without SBP. However, there was no effect of SBP in pigs offered 150 g/kg CP diets. Manure ammonia emissions were reduced by 33% from 0 to 240 h (P < 0.01); however, odour emissions were increased by 41% (P < 0.05) when pigs were offered SBP diets. Decreasing dietary CP to 150 g/kg reduced total N excretion (P < 0.001) and ammonia emissions from 0 to 240 h (P < 0.05). There was an interaction between dietary CP and SBP on branched-chain fatty acids (P < 0.001) in caecal digesta. Pigs offered the 200 g/kg CP SBP-containing diet reduced branched-chain fatty acids in the caecum compared with pigs offered the 200 g/kg CP diet containing no SBP. However, there was no effect of SBP in the 150 g/kg CP diet. In conclusion, pigs offered SBP-containing diets had a reduced manure ammonia emissions and increased odour emissions compared with diets containing no SBP. Pigs offered the 200 g/kg CP SBP-containing diet had a reduced urine : faeces N ratio and urinary N excretion compared with those offered the 200 g/kg CP diet containing no SBP.     

Effects of dietary crude protein level on odour from pig manure

The objective of this study was to determine the effects of dietary crude protein (CP) level on odour emission, odour intensity, hedonic tone, and ammonia emission from pig manure and on manure composition (pH, total nitrogen, ammonium, volatile fatty acids, indolic, phenolic and sulphur-containing compounds). An experiment was conducted with growing pigs (n = 18) in a randomised complete-block design with three treatments in six blocks. Treatment groups were 12%, 15% and 18% CP diets. Barley was exchanged for soya-bean meal. Crystalline amino acids (AA) were included in the 12% CP diet up to the level of pigs' requirement; the same amount of AA was added to the 15% and 18% CP diets. Pigs with an initial body weight (BW) of 36.5 ± 3.4 kg (mean ± s.d.) were individually penned in partly slatted floor pens and offered a daily feed allowance of 2.8 × maintenance requirement for net energy (NE: 293 kJ/kg BW^0.75). Feed was mixed with water, 1/2.5 (w/w). Faeces and urine of each pig were accumulated together in a separate manure pit under the slatted floor. After an adaptation period of 2 weeks, the manure pits were cleaned and manure was collected. In the 5th week of the collection period, air samples for odour and ammonia analyses, and manure samples were collected directly from each manure pit. Air samples were analysed for odour concentration and for hedonic value and intensity above odour detection threshold. Manure samples were analysed for volatile fatty acids, and indolic, phenolic and sulphurous compounds, ammonium and total nitrogen concentrations. Reducing dietary CP from 18% to 12% lowered odour emission ( P < 0.05) and ammonia emission ( P = 0.01) from pig manure by 80% and 53%, respectively. Reduced dietary CP decreased total nitrogen, methyl sulphide, carbon disulphide, ethanethiol, phenol, 4-ethyl phenol, indole and 3-methyl indole concentrations in the manure ( P < 0.05). Volatile fatty acids and cresols concentrations in the manure of pigs fed different dietary CP levels were similar. A reduction of dietary CP and at the same time providing essential AA is an option to reduce odour emission as well as ammonia emission from pig manure.     

The effect of high and low dietary crude protein and inulin supplementation on nutrient digestibility, nitrogen excretion, intestinal microflora and manure ammonia emissions from finisher pigs

A 2 × 2 factorial experiment was performed to investigate the interaction between a high- and low-crude-protein (CP) diet (200 v. 140 g/kg) and inulin supplementation (0 v. 12.5 g/kg) on nutrient digestibility, nitrogen (N) excretion, intestinal microflora, volatile fatty acid (VFA) concentration and manure ammonia emissions from 24 boars (n = 6, 74.0 kg live weight). The diets were formulated to contain similar concentrations of digestible energy and lysine. Pigs offered the high-CP diets had a higher excretion of urinary N (P < 0.001), faecal N (P < 0.01) and total N (P < 0.001) than the pigs offered the low-CP diets. Inulin supplementation increased faecal N excretion (P < 0.05) and decreased the urine N : faeces N ratio (P < 0.05) compared with the inulin-free diets. There was no effect (P > 0.05) of dietary treatment on N retention. There was an interaction (P < 0.05) between dietary CP concentration and inulin supplementation on caecal Enterobacteria spp. Pigs offered the diet containing 200 g/kg of CP plus inulin decreased the population of Enterobacteria spp. compared to those with the inulin-supplemented 140 g/kg CP diet. However, CP level had no significant effect on the population of Enterobacteria spp. in the unsupplemented diets. Inulin supplementation increased caecal Bifidobacteria (P < 0.01) compared with the inulin-free diets. There was no effect of inulin supplementation on VFA concentration or intestinal pH (P > 0.05). Pigs offered the 200 g/kg CP diets had higher (P < 0.05) manure ammonia emissions from 0 to 240 h of storage than pigs offered the 140 g/kg CP. In conclusion, inulin supplementation resulted in an increase in Bifidobacteria concentration and a reduction in Enterobacteria spp. at the high CP level indicating that inulin has the ability to beneficially manipulate gut microflora in a proteolytic environment.     

The effect of cereal type and enzyme supplementation on carcass characteristics, volatile fatty acids and intestinal microflora and boar taint in entire male pigs

A 2 × 2 factorial experiment was conducted to investigate the effects of cereal type (barley v. oat) and exogenous enzyme supplementation (with or without) on intestinal fermentation, and on indole and skatole levels in the intestinal content and the adipose tissue in finisher boars. The experimental treatments were as follows: (i) barley-based diet, (ii) barley-based diet with enzyme supplement, (iii) oat-based diet and (iv) oat-based diet with enzyme supplement. The enzyme supplement contained endo-1,3(4)-β-glucanase (EC 3.2.1.6) and endo-1,4-β-xylanase (EC 3.2.1.8). The animals were fed ad libitum for 45 days from 76.0 to 113.6 kg live weight. Feeding barley-based diets led to higher (P < 0.05) total volatile fatty acids concentrations in the large intestine. Proportions of propionic- and butyric-acids were higher and that of acetic acid lower in digesta from barley-based in comparison to oat-based diets (P < 0.001). Consequently, pH in the large intestine was higher after feeding oat-based in comparison to barley-based diets. Animals fed unsupplemented oat-based diet had higher (P < 0.01) indole concentrations in the digesta from the proximal colon than those fed barley-based diets. Feeding oat-based diets led to lower (P < 0.01) skatole and higher (P < 0.001) indole concentrations in the digesta from the terminal colon than barley-based diets. skatole concentrations in the adipose tissue did not differ (P > 0.05) between the experimental treatments. Pigs offered the barley-based diets had lower (P < 0.001) indole concentrations in the adipose tissue compared with those fed the oat-based diet. In conclusion, barley-based diets were more efficient than oat-based diets in limiting concentrations of indole in the adipose tissue.     

Effect of cereal type and plant extract addition on the growth performance,intestinal morphology,caecal microflora,and gut barriers gene expression of broiler chickens

Feeding broiler chickens on diets based on cereal grains of high non-starch polysaccharides content such as wheat and barley can negatively impact their performance and gut health. Plant extracts can be used as a potential tool to alleviate these negative effects. The present study assessed the effects of dietary cereal type and the inclusion of a plant extract blend (PEB) on the growth performance, intestinal histomorphology, caecal microflora, and gene expression of selected biomarkers for gut integrity in broiler chickens in a 42-d experiment. Ross-308 male broilers were assigned into different dietary treatments and fed on two cereal types (corn- vs. wheat/barley-based) with/without added graded concentrations of a PEB (0, 250, 500, 1000, and 2000 mg/kg diet). There were no significant differences in the growth performance parameters, intestinal histomorphology, and caecal microflora due to the impact of dietary cereal type. However, lactobacilli count in the caecal microflora was increased in the group fed on a corn-based diet. The PEB supplementation especially at a level of 500 to 1000 mg/kg diet significantly increased the average BW and decreased the feed conversion ratio. It also increased the villi length of duodenum, jejunum, and ileum, decreased the duodenal crypt depth, and increased the villi length to crypt depth ratio in the duodenum, jejunum and ileum. Supplementation of the PEB decreased the total bacterial and coliform count and increased the lactobacilli count in a linear pattern. Gene expression of Occludin and Junction Adhesion Molecule was significantly increased in the PEB supplemented diets, whereby no influence was observed on mucin expression. In conclusion, supplementation of a PEB at levels of 500–1000 mg/kg can be used as a tool to improve broiler performance and gut health.     

The influence of diet crude protein level on odour and ammonia emissions from finishing pig houses

Feed trials were carried out to assess the influence of crude protein content in finishing pig diets on odour and ammonia emissions. Eight pigs (4 boars and 4 gilts), average initial weight 70.8 kg (s.e. 3.167) were housed in two pens that were isolated from the rest of a pig house at University College Dublin Research Farm, Newcastle, Dublin, Ireland. Four diets containing 130, 160, 190 and 220 g x kg(-1) crude protein were fed during six four-week feeding periods (one treatment per room). The first week of the feeding periods served to allow odour build up in the pens and as a dietary adjustment period. The pens had partially slatted floors that were cleaned and had all the manure removed after each four-week period. Odour and ammonia concentrations were measured on days 9, 14, 16, 21 and 23 of each trial period. Odour samples were collected in Nalophan bags and analysed for odour concentration using an ECOMA Yes/No olfactometer. The odour threshold concentration was calculated according to the response of the olfactometry panel members and was displayed in Ou(E)m(-3), which referred to the physiological response from the panel equivalent to that elicited by 40 ppbv(-1) n-butanol evaporated in 1 m(3) of neutral gas. Ammonia concentrations in the ventilation air were measured using Dr?ger tubes. The odour emission rates per animal for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 12.1, 13.2, 19.6 and 17.6 Ou(E)s(-1)animal(-1), respectively (P<0.01). The odour emission rate per livestock unit (500 kg) for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 77.6, 80.0, 115.8 and 102.9 Ou(E)s(-1)LU(-1), respectively (P<0.01). The ammonia emission rates per animal for the 130, 160, 190 and 220 g x kg(-1) crude protein diets were 3.11, 3.89, 5.89 and 8.27 g x d(-1)animal(-1), respectively (P0.05). Manipulation of dietary crude protein levels would appear to offer a low cost alternative, in relation to end-of-pipe treatments, for the abatement of odour and ammonia emissions from finishing pig houses.     

The effect of eubiotic feed additives on the performance of growing pigs and the activity of intestinal microflora

The aim of this study was to compare the effect of probiotic bacteria, prebiotics, phytobiotics and their combinations on performance and microbial activity in the digestive tract of growing pigs. The experiment was conducted over 28 d on 48 male pigs of about 12 kg body weight (BW), which were allocated to following treatments.: (1) Control Group (Con) without additive, (2) Group I, addition of a prebiotic (inulin), (3) Group Ph, a phytobiotic (herbal water extracts), (4) Group P, a probiotic composed of four strains of lactic acid bacteria, (5) Group PhP, phytobiotic and probiotic bacteria and (6) Group PhPI, a phytobiotic, probiotic bacteria and a prebiotic. Animal performance was recorded and at d 28 six pigs from each group were euthanised to collect digesta samples. In all groups except for Group I, diarrhoea incidents were observed. Groups Ph and P had significantly higher daily gains and final BW, and Group Ph utilised feed better than other groups. The pH of ileal digesta was significantly lower in Group PhPI. In the caecal digesta of Groups I, P and PhP, the pH level was lower than in the other groups but dry matter contents was significantly higher in Groups Con and I. The short-chain fatty acids and particular acid content differed significantly only in the colonic digesta. The yeast and mould numbers in caecal digesta was highest in Group Con. No treatment effects were observed for the number of lactic acid bacteria, coli group bacteria or Clostridium. However, the observed significantly higher number of total bacteria suggests that a multi-component eubiotic treatment changes the bacterial composition and distribution more effectively. Our findings indicated that all used additives changed the intestinal microflora, but the multi-component eubiotics were not beneficial as feed additives offered separately. Moreover, supplementation of phytobiotics and probiotic bacteria also improved the animal performance significantly.     

The effect of benzoic acid concentration on nitrogen metabolism,manure ammonia and odour emissions in finishing pigs

A complete randomised block design experiment was conducted to investigate the effects of benzoic acid inclusion level on nitrogen (N) metabolism, and manure ammonia (NH₃) and odour emissions in finishing pigs. Sixteen boars (64 kg live weight ± 1.5 kg) were assigned to one of four dietary treatments (T) varying in benzoic acid concentration: (T1) 0 g benzoic acid/kg (as fed); (T2) 10 g benzoic acid/kg; (T3) 20 g benzoic acid/kg; (T4) 30 g benzoic acid/kg. Animals were housed in individual metabolism crates and feed was provided ad libitum. All diets were formulated to have similar concentration of digestible energy and ileal digestible lysine with benzoic acid replacing wheat in the diet. There was a linear decrease in NH₃ emission (P<0.001), as the dietary benzoic acid concentration increased (141.4 mg/g versus 40.5 mg/g N intake (S.E.M. 12.1) over the 240-h storage period). However, there was no effect (P>0.05) of benzoic acid on odour concentration. Urinary nitrogen (N) excretion, total N excretion and the urinary:faecal N ratio were linearly reduced (P<0.05) with increasing benzoic acid inclusion. Furthermore, N retention increased linearly (P<0.05) as benzoic acid concentration increased from 0 g/kg to 30 g/kg in the diet. In conclusion, the inclusion of benzoic acid in the diet of finishing pigs has the potential to reduce total and urinary N excretion and the urinary to faecal N ratio. This was mirrored by reductions in manure NH₃ emissions in the benzoic acid supplemented treatments.     

The effect of sex and slaughter weight on performance,carcass quality and gross margin,assessed on three commercial pig farms

Economic margins on pig farms are small, and changing slaughter weights may increase farm profitability. However, one can question if the optimal slaughter weight is the same for each sex. On three farms, crossbred pigs (n = 1128) were used to determine the effect of sex and slaughter weight on performance, carcass quality and gross margin per pig place per year. On each farm, an equal number of entire males (EMs), barrows (BAs), immunocastrates (IC) and gilts (GIs) were housed separately in group pens. Pens were randomly divided into three categories of different slaughter weights: 105, 117 and 130 kg BW. In BA, the high average daily feed intake (ADFI) and the lower capacity to gain muscle led to a higher feed conversion ratio (FCR) and lower lean meat percentage in comparison to EM and IC. In all sexes, ADFI and FCR increased with an increasing slaughter weight but the effect of slaughter weight on carcass quality varied between sexes. In BA and GI, slaughter weight had no effect on carcass quality, but in EM and IC, carcass quality improved at higher slaughter weights. Gross margin per pig place per year was calculated as gross margin per pig × barn turnover per year, taking into account fixed costs per round, feed costs and output price per pig. The slaughter weight that gained the highest gross margin per year differed between sexes. Slaughtering BA and GI at 130 kg BW, compared to 105 or 117 kg BW, decreased the gross margin per pig place per year due to the lower margin per pig and barn turnover at higher weights. In IC and EM, no difference in gross margin per pig place per year could be demonstrated between slaughtering at 105, 117 or 130 kg BW. In IC, the increasing gross margin per pig with increasing slaughter weights counteracted with the lower barn turnover. In EM, gross margin per pig did not differ between slaughter weights, but the effect of barn turnover was too small to demonstrate significant differences between slaughter weights on gross margin per pig place per year. In conclusion, slaughter weight has an impact on profitability in BA and GI: they should not be slaughtered at 130 kg BW but at lower weights, but no effect could be demonstrated in EM and IC.     

饲养方式对藏猪结肠消化酶活性、菌群结构及短链脂肪酸含量的影响

【目的】为探究饲养方式对藏猪结肠消化酶活性、菌群结构和短链脂肪酸含量的影响。【方法】研究分别选取5头相同月龄的放养藏猪和舍饲藏猪。屠宰采集结肠粪便样品,分别利用酶联免疫吸附法(enzyme linked immunosorbent assay, ELISA)试剂盒、高通量测序技术和气相色谱仪测定放养藏猪和舍饲藏猪结肠消化酶活性、菌群结构和短链脂肪酸含量。【结果】同一月龄下,放养藏猪的日增重显著低于舍饲藏猪(P<0.05)。放养藏猪结肠中纤维素酶和半纤维素酶的活性均显著高于舍饲藏猪(P<0.05);2种饲养方式藏猪结肠的6种α多样性指数均无显著差异(P>0.05),且主成分分析(principal component analysis, PCA)得到放养藏猪和舍饲藏猪结肠菌群存在一定的相似性。在门和科分类水平上,相较于舍饲藏猪,放养藏猪结肠中疣微菌门、黄杆菌科、月形单胞菌科、浮霉状菌科和伊格尔兹氏菌科的相对丰度显著升高,而链球菌科、韦荣氏球菌科、假单胞菌科、红环菌科、红螺菌科、乳杆菌科、理研菌科和巴斯德氏菌科的相对丰度显著降低(P<0.05);在属和种分类水平上,...     

Effect of biofuel co-products in pig diets on the excretory patterns of N and C and on the subsequent ammonia and methane emissions from pig effluent

This study was conducted to investigate the effects of incorporation into pig diets of 20% of different co-products from the biofuel industries, which are rich in fibre, on animal growth performance, on nitrogen (N) and carbon (C) excretions, and on the subsequent ammonia volatilisation and methane production during the storage of slurry. Five experimental diets mainly based on wheat and soyabean meal were formulated: two control diets, a control high-protein (CHP) diet with 17.5% of crude protein (CP) and a control low-protein (CLP) diet with 14.0% of CP and three experimental diets with 20% of (i) dried distiller's grain with solubles (DDGS), (ii) sugar beet pulp (SBP) or (iii) fatty rapeseed meal (FRM). The animals used (20 castrated males) were housed individually in metabolism cages and fed one of the five diets (i.e. four pigs per diet). Urine and faeces were collected separately from each pig in order to measure nutrient digestibility and the excretory patterns of N and C. For each diet, ammonia volatilisation was measured from samples of slurry subsequently produced, over a 16-day storage period in a laboratory pilot scale system. The ultimate methane potential (B0, expressed in litres CH4/kg organic matter (OM)) was measured from the same slurry, for each diet, in anaerobic storage conditions over 100 days. The addition of sources of fibres to the diet decreased (P < 0.05) the animal growth performance by 13% and increased (P < 0.05) the amount of faeces excreted by 100%, whereas the amount of urine was not affected. For the high-fibre diets, there was a shift of N partitioning from urine to faeces, resulting in a much higher faecal N excretion (10 v. 5 g N/pig per day). Concurrently, the fibre enrichment in diets significantly increased (P < 0.05) the C content of the faeces by 68%. Ammonia emission from slurry was significantly reduced (P < 0.05) by 19% to 33% for the high-fibre diets, compared to the CHP diet. Ammonia emission was also reduced (P < 0.05) by 33% for the CLP compared to the CHP diet. B0 values ranged from 428 to 484 l CH4/kg OM. When these are expressed per pig and per day, the B0 from slurry was, on average, 70 l for the two control diets, and 121, 91 and 130 l for the slurry originating from the DDGS, SBP and FRM diets, respectively.     

Effects of prefermented cereals or the end products of fermentation on growth and metabolism of enterocyte-like Caco-2 cells and on intestinal health of restrictedly fed weanling pigs

To unravel the underlying mechanisms that explain the positive effects of prefermented cereals on in vivo gastrointestinal (GI) architecture and function, an in vitro experiment using a human small intestinal epithelial cell model (Caco-2) was performed. A range of dilutions (0% to 10%) of the supernatants of three liquid experimental diets, as well as Na-lactate were used in an in vitro experiment to assess their effect on cellular growth, metabolism, differentiation and mucosal integrity using Caco-2. The experimental diets contained, in addition to a protein rich basal diet (60%), (1) a liquid control diet (C) containing 40% of a mixture of barley and wheat (ratio 3 : 1) or (2) a liquid diet (F) containing 40% prefermented barley and wheat or (3) C with the addition of the fermentation end-products (organic acids and ethanol) in concentrations similar to those in the fermented diet (FP). For F, the mixture of barley and wheat was fermented at 35°C for 48 h. Parallel to the in vitro experiment, 18 groups of eight weanling pigs were assigned to one of the experimental diets during a 14-day in vivo experiment. Each group was fed restrictively. The results of the in vitro experiment showed that the lowest dose of both F- and FP-supernatants had no clear effects on the cell proliferation, but incubation with 5% and 10% of the F- and FP-supernatants decreased the cell numbers at day 19. DNA, RNA, protein and glycoprotein synthesis in differentiated Caco-2 cells were stimulated by incubation with the lower concentrations (0.5% to 2.5%) of F- and FP-supernatants whereas the higher concentrations (5% and 10%) had no effect. Both the F- and FP-supernatants decreased the specific sucrase-isomaltase activity in a dose-dependent manner, but the effects on the specific aminopeptidase activities were less clear. Mucosal integrity initially decreased after incubation with the highest F- and FP-supernatants and started to recover between 24 and 48 h. The results of the in vivo experiment showed no dietary effects (P > 0.1) on GI morphology and brush-border enzyme activities at day 5 or at day 14. Time related changes in GI characteristics followed a normal pattern. In conclusion, the supernatants of diets containing either prefermented cereals or their fermentation end-products clearly modulate cellular growth, metabolism, differentiation and mucosal integrity in an in vitro model, although these effects were not observed in the in vivo characteristics measured in weanling pigs.     

Effect of age of growing turkeys on digesta viscosity and nutrient digestibility of maize,wheat, barley and oats fed as such or with enzyme supplementation

The effects of age of growing turkeys and β-glucanase-xylanase activity-containing feed enzyme supplementation on digestibility and feeding value of pelleted maize, wheat, barley and oats were investigated in growing turkeys using excreta collection and ileal sampling by slaughter. Excreta were collected and turkeys were slaughtered at 4, 8 and 12 weeks of age. Viscosity of jejuno-duodenal digesta, caecal volatile fatty acid concentration, ileal crude protein digestibility, total tract fat digestibility and AME_N were assayed using titanium dioxide as an indigestible marker. The highest viscosities were observed in barley and wheat. Viscosity of wheat, barley and oats digesta decreased while caecal volatile fatty acid concentration, fat digestibility and AME_N increased with age. Ileal crude protein digestibility was highest in wheat and lowest in barley. Ileal crude protein digestibility significantly declined with age in most feeding treatments. Enzyme reduced digesta viscosity most efficiently in wheat and barley and improved ileal crude protein digestibility, total tract fat digestibility and AME_N in wheat, barley and oats, but interactions occurred, the effect of enzyme on viscosity being the most remarkable for wheat and barley and for the young birds.     

Effect of fibre sources on performance,serum parameters,intestinal morphology,digestive enzyme activities and microbiota in weaned pigs

ABSTRACT

This study was conducted to evaluate the effects of wheat bran (WB) as insoluble fibre source, and sugar beet pulp (SBP) as soluble fibre source, on performance, serum parameters and intestinal health in weaned pigs. A total of 90 weaned pigs (BW: 7.33 ± 1.24 kg) were randomly assigned to three dietary treatments: (1) a control diet (CON) based on corn and soybean meal; (2) CON + 6% WB; (3) CON + 6% SBP. Each treatment had five replicate pens with six pigs per pen. The experimental period was divided into two phases (d 0 to 14 and d 14 to 28). Pigs in group WB tended to have greater avarage daily gain than those in group SBP. Compared with CON, SBP reduced (p < 0.05) the apparent total tract digestibility (ATTD) of dry matter, organic matter (OM), gross energy and neutral detergent fibre on d 14 and 28, while WB decreased (p < 0.05) the ATTD of OM on d 28. Pigs in group SBP had higher (p < 0.05) glucagon-like peptide 1 concentration than the other groups on d 14 and 28. The villus height to crypt depth (V:C) ratio of duodenum and jejunum in pigs fed diet WB were greater (p < 0.05) than in group SBP. The WB increased (p < 0.05) the V:C ratio of ileum compared with CON or SBP. Compared with SBP, WB increased (p < 0.05) the sucrase activity in the duodenum. Moreover, pigs in WB had higher (p < 0.05) activities of maltase and sucrase in the jejunum compared with CON or SBP. The abundances of Ruminococcaceae and Prevotellaceae were increased (p < 0.05) in WB, while the Lachnospiraceae abundance was increased (p < 0.05) in SBP. WB increased (p < 0.05) concentrations of acetate, butyrate and total short-chain fatty acids (SCFA), while SBP increased (p < 0.05) concentrations of acetate and total SCFA when compared with CON. In conclusion, WB was beneficial to performance in weaned pigs by improving morphology, enzyme activities and microbiota when compared with SBP, highlighting that effects of fibre depends on the fibre sources.     

The effect of host odour on the landing responses of tsetse flies (Glossina morsitans morsitans) in a wind tunnel with and without visual targets

Abstract The effect of artificial host odour on the landing responses of males of Glossina m.morsitans West, and on their reaction to visual targets has been investigated in a wind tunnel. Landing was induced in flies that traversed steep odour gradients as they flew upwind and downwind across the edge of an odour plume, irrespective of whether visual targets were present or not; the landing response could be elicited over a wide range of odourconcentrations. When targets were present such odour gradients also tended to increase the proportion of landing flies which alighted on or near the targets; and the bigger the target, or the hungrier the flies, the greater was the propensity for target landing. In air which was more uniformly permeated with odour, the propensity to land on targets was increased only at high odour concentration.     

Consequences of timing of organic enrichment provision on pig performance,health and stress resilience after weaning and regrouping

Most pigs in slatted systems are provided with enrichment meeting only minimum legal requirements. We aimed to explore the effects of a novel enrichment treatment consisting of daily provided fodder beet and jute bags for pigs in slatted systems, and investigate the timing of enrichment provision on performance, health and stress resilience. We used 280 weaners allocated into standard (S, meeting only legal requirements consisting of a plastic toy and softwood) or enriched (E) treatment (n = 14 groups/treatment). At regrouping during the grower to finisher transition, pigs were either kept in the same treatment (EE, SS) or switched from enriched to standard (ES) and vice versa (SE); each treatment was replicated on five groups. Pigs were weighted at the start and end of weaner, and finisher stage, and feed intake was recorded. Occurrence of scouring, respiratory problems, locomotor disorders, tail, ear, and body lesions were recorded twice a week. Ten males per treatment were sampled for saliva on days 1, 2 and 4, either postweaning or after the housing switch. Saliva samples were analysed for cortisol, alpha-amylase, haptoglobin (Hp), and adenosine deaminase. Additionally, these pigs were sampled for hair at the start and end of weaner, and end of finisher stage to analyse for hair cortisol and cortisone. We found that E weaners consumed less feed (P = 0.04), had better FCR (feed conversion ratio, P = 0.03) and less ear lesions for two weeks postweaning (P = 0.04), and tended to have lower occurrence of scouring (P = 0.07) and higher salivary cortisol concentrations (P = 0.09) than S weaners. Effects of enrichment treatment during weaner stage on performance were carried through to finisher stage, with EE and ES pigs having better FCR (P = 0.0009) and higher BW (P = 0.0001) compared to SS and SE pigs. E treatment during finisher stage decreased feed intake (P = 0.04) and tended to decrease Hp levels (P = 0.07). There was a significant interaction between enrichment treatments during weaner and finisher stages on finisher body lesions: EE finishers had less lesions than SS, ES, and SE finishers (P = 0.04). There were no other significant differences caused either by enrichment treatment during weaner/finisher stage or their interaction. We conclude that the novel enrichment applied at weaner stage had positive effects on ear lesions and performance, which were carried through to finisher stage. Body lesions were affected by its application during both stages, with finishers receiving the enrichment treatment throughout (EE) having reduced body lesions than the rest of the finishers.     

Sensory detection of food odour in relation to dental status,gender and age

The aim of this study was to investigate to what extent declining odour perception can be ascribed to dental status and oral hygiene habits, taking into account gender and age. Apparently healthy adults (n=182), ranging from 53 to 93 years (mean age=68.4) were tested. Information about oral hygiene habits (brushing teeth and cleaning dentures) and dental status was obtained by questionnaires. A validated objective procedure was used to measure sensory detection thresholds for isoamylacetate by an ascending method of limits. A significant negative correlation of odour perception with age was shown by the edentulous subjects which might reflect their wider age spread with many subjects over age 75. The evaluation of odour perception as a function of dental status shows no significant difference in odour perception between persons partial denture wearers, with natural teeth only or complete dentures. However, a tendency for lower odour perception was observed among male partial denture wearers, especially those reporting less frequent oral hygiene, which justifies further more detailed study.     

小檗碱对肠易激综合征大鼠肠道菌群的影响

目的 通过口服小檗碱（Berberine,BBR）治疗大鼠肠易激综合征（IBS）,初步研究小檗碱对IBS大鼠肠道菌群的影响。方法 用避水应激试验制作大鼠IBS模型,分别给予模型大鼠小剂量（25 mg/kg）小檗碱、大剂量（100 mg/kg）小檗碱和利福昔明干预治疗10 d,检测大鼠肠道菌群丰度、生物多样性及菌群结构组成的变化。结果 避水应激试验造模后模型组大鼠排便次数增多、腹外斜肌EMG明显升高,肠道可见微炎症表现。小檗碱干预后,IBS大鼠排便增多情况、内脏高敏感性和肠道微炎症情况均显著改善,其中大剂量小檗碱组优于小剂量组。经小檗碱干预后,大鼠肠道菌群多样性显著降低,大剂量小檗碱抑菌作用强于小剂量小檗碱。大剂量小檗碱可显著提高IBS大鼠肠道乳杆菌科细菌的比例,同时降低肠杆菌科细菌的比例。结论 小檗碱可以显著降低IBS大鼠内脏高敏感性,改善肠道微炎症,减少IBS大鼠排便增多症状。小檗碱可以调节肠道菌群丰度和多样性,且剂量越大,抑菌作用越明显。肠道乳杆菌科细菌在小檗碱治疗肠易激综合征的过程中可能起一定作用。     

Effects of in utero odorant exposure on neuroanatomical development of the olfactory bulb and odour preferences

Human babies and other young mammals prefer food odours and flavours of their mother's diet during pregnancy as well as their mother's individually distinctive odour. Newborn mice also prefer the individual odours of more closely related--even unfamiliar--lactating females. If exposure to in utero odorants-which include metabolites from the mother's diet and the foetus's genetically determined individual odour-helps shape the neuroanatomical development of the olfactory bulb, this could influence the perception of such biologically important odours that are preferred after birth. We exposed gene-targeted mice during gestation and nursing to odorants that activate GFP-tagged olfactory receptors (ORs) and then measured the effects on the size of tagged glomeruli in the olfactory bulb where axons from olfactory sensory neurons (OSNs) coalesce by OR type. We found significantly larger tagged glomeruli in mice exposed to these activating odorants in amniotic fluid, and later in mother's milk, as well as significant preferences for the activating odour. Larger glomeruli comprising OSNs that respond to consistently encountered odorants should enhance detection and discrimination of these subsequently preferred odours, which in nature would facilitate selection of palatable foods and kin recognition, through similarities in individual odours of relatives.     

Effects of addition of calcium and magnesium salts on ammonia volatilization during manure decomposition

Ammonia volatilization during aerobic decomposition of poultry manure was significantly reduced through additions of calcium and magnesium salts. The percentage reduction in ammonia loss decreased during the 48 day decomposition period from 85–100% in the first 2–3 weeks, to 23–52% at the end of the experiment. The maximum amount of ammonia which was retained (i.e. maximum reduction in ammonia loss) through addition of the chloride salts of Mg²⁺ or Ca²⁺ was independent of the type of cation. However, CaCl₂ released some of the ammonia initially retained as production of CO₂ and NH₃ from the manure decreased after 3 weeks of decomposition, whereas both MgCl₂ and MgSO₄ did not release any of the initially retained ammonia over the 7 week incubation period. Over the entire incubation period MgCl₂ therefore retained more ammonia than CaCl₂. Magnesium sulphate was considerably less effective in retaining ammonia than either chloride salts.