The effect of dietary phosphorus and calcium level, phytase supplementation, and ileal infusion of pectin on the chemical composition and carbohydrase activity of fecal bacteria and the level of microbial metabolites in the gastrointestinal tract of pigs

Two experiments with growing pigs were conducted to determine the effects of dietary P and Ca level, phytase supplementation, and ileal pectin infusion on ileal and fecal P and Ca balance, chemical composition of fecal mixed bacterial mass (MBM), and bacterial metabolic activity. Pigs (initial BW = 30 kg) were fitted with simple T-cannulas at the distal ileum. They were fed a low-P corn-soybean meal control diet (3 g of P/kg) or the control diet supplemented with monocalcium phosphate (MCP; 7 g of P/kg; Exp. 1) or 1,000 FTU phytase/kg (Exp. 2). The daily infusion treatments consisted of 60 g of pectin dissolved in 1.8 L of demineralized water or 1.8 L of demineralized water as the control infusion, infused via the ileal cannula. In each experiment, 8 barrows were assigned to 4 dietary treatments according to a double, incomplete 4 x 2 Latin square. The dietary treatments in Exp. 1 were the control (Con-) diet with water infusion; the control (Con+) diet with pectin infusion; the MCP diet with water infusion; and the MCP diet with pectin infusion. In Exp. 2, the pigs received the same Con- and Con+ treatments as in Exp. 1 and, in addition, the phytase-supplemented diet in combination with water or pectin infusion. After a 15-d adaptation period, feces were collected for 5 d followed by ileal digesta collection for 24 h. In Exp. 1, supplemental MCP increased (P 相似文献   

Influence of protein fermentation and carbohydrate source on in vitro methane production

Incubations were carried out with batch cultures of ruminal micro‐organisms from sheep to analyse the influence of the N source on in vitro CH₄ production. The two substrates were mixtures of maize starch and cellulose in proportions of 75:25 and 25:75 (STAR and CEL substrates, respectively), and the three nitrogen (N) sources were ammonia (NH₄Cl), casein (CA) and isolated soya bean protein (SP). Five isonitrogenous treatments were made by replacing non‐protein‐N (NPN) with CA or SP at levels of 0 (NPN), 50 (CA50 and SP50, respectively) and 100% (CA100 and SP100) of total N. All N treatments were applied at a rate of 35 mg of N/g of substrate organic matter and incubations lasted 16.5 h. With both proteins, N source × substrate interactions (p = 0.065 to 0.002) were detected for CH₄ production and CH₄/total VFA ratio. The increases in CH₄ production observed by replacing the NPN with protein‐N were higher (p < 0.05) for STAR than for CEL substrate, but the opposite was observed for the increases in volatile fatty acid (VFA) production. As a consequence, replacing the NPN by increased levels of CA or SP led to linear increases (p < 0.05) in CH₄/total VFA ratio with STAR, whereas CH₄/total VFA ratio tended (p < 0.10) to be decreased with CEL substrate. Increasing the amount of both proteins decreased linearly (p < 0.05) ammonia‐N concentrations, which may indicate an incorporation of amino acids and peptides into microbial protein without being first deaminated into ammonia‐N. In incubations with the tested N sources as the only substrate, the fermentation of 1 mg of CA or SP produced 1.24 and 0.60 μmol of CH₄ respectively. The results indicate the generation of CH₄ from protein fermentation, and that the response of CH₄ production to protein‐N supply may differ with the basal substrate.     

Efficiency of microbial phytase supplementation in diets formulated with different calcium:phosphorus ratios,supplied to broilers from 22 to 33 days old

An experiment was conducted with broilers from 22 to 33 days of age to evaluate the efficiency of six microbial phytases supplemented in diets (1500 FTU/kg) that were formulated with three different calcium:available phosphorus (Ca:P_avail) ratios (4.5:1.0, 6.0:1.0 and 7.5:1.0). A positive control diet without phytase was formulated with a Ca:P_avail ratio of 7.5:3.4 to meet the nutritional requirements of the broilers. The P and ash contents of the tibia, magnesium in the plasma, performance, balance and retention of phytate phosphorus (P_phyt), intake of total P and nitrogen (N), nitrogen‐corrected apparent metabolizable energy and apparent digestibility of dry matter of the diets were not influenced (p > 0.05) by the type of phytase or the dietary Ca:P_avail ratio. However, there was an interaction (p < 0.05) between the phytase type and the Ca:P_avail ratio for the retention coefficients of total P, Ca and N. Phytase B resulted in the highest Ca deposition in the tibia (p < 0.01). Phytases D, E and F reduced the Ca concentrations in the tibia (p < 0.01) and plasma (p < 0.05). Phytase D increased the P level in the plasma and decreased the total P excretion (p < 0.01). Phytases E and F increased Ca excretion, while phytase A reduced it (p < 0.01). Regardless of the phytase type, increasing the dietary Ca:P_avail ratio reduced (p < 0.05) the plasma P concentration and the excretion of total P and N and, conversely, increased (p < 0.05) the plasma concentration, intake and excretion of Ca. For the rearing period evaluated, it is possible to reduce the P_avail of the diet to 1.0 g/kg when Ca is maintained at 7.5 g/kg, and the diet is supplemented with 1500 FTU of phytase A, C, D or E/kg. This diet allows the maintenance of performance and adequate bone mineralization, and it improves the Ca, total P and P_phyt utilization in addition to reducing the excretion of N and P into the environment.     

ORIGINAL ARTICLE: Effect of rendering on protein and fat quality of animal by‐products

This work studies the effect of rendering on quality of meat and bone meals (MBM) processed in two Spanish rendering plants according to the standard procedure recommended by 96/499/EC Directive for MBM category III. Twelve samples of raw animal by‐products and their corresponding meals were analysed for chemical composition, amino acids (AA) content, FDNB‐reactive lysine content, pepsin digestibility, protein dispersibility index (PDI) and fatty acids (FA) content. There was a high variation in MBM composition between and within plants, mainly in the ash and fat content. Rendering caused a decrease in the total (p < 0.05) and the essential (p < 0.01) AA content (in crude protein basis) in both plants, because of a decrease in lysine (p < 0.001), methionine (p < 0.05), threonine (p < 0.01), leucine (p < 0.01), valine (p < 0.01) and phenylalanine (p < 0.01). Besides, there was a reduction in the cystine (p < 0.001), serine (p < 0.01) and aspartic acid (p < 0.01) content. The FDNB‐reactive lysine to total lysine ratio and pepsin digestibility only decreased (p < 0.001) in the plant with more severe treatment conditions, whereas the PDI increased (p < 0.05) by the process in both plants. The saturated to unsaturated FA ratio increase on average from 0.73 to 0.88 after rendering, because of the decrease in both linoleic and linolenic acids content and the increase in palmitic and stearic acids content. The results indicate that rendering has negative effects on protein and fat quality of MBM. Variability between and within plants is attributed to differences in raw material, processing conditions and fat removing efficiency. Therefore, a continuous monitoring is recommended to assure the quality of each batch before use.     

Pre-treatment of dietary plant feedstuffs with phytase and its effect on growth and mineral concentration in common carp (Cyprinus carpio L.)

Effect of phytase pre-treatment of dietary plant feed stuffs (PF) on growth and mineral concentration in common carp (C. carpio L.) was investigated. Diets used were: C0, diet with no supplement; CI, diet with incubated PF; CP0, diet supplemented with 3 g P/kg; CPI, diet with incubated PF supplemented with 3 g P/kg; Phyt0, diet fortified with 4000 U phytase/kg; PhytI, diet with PF incubated with 4000 U phytase/kg. Mean weight gain, SGR and FCR were the same (p < 0.05) in fish fed CP0, CPI or PhytI but less (p < 0.05) in other fish. Bone P was similar in fish fed CP0 (74.9), CPI (75.9) or PhytI (71.5 mg/g DM) but higher (p < 0.05) than in fish fed C0. Bone Ca and Mg were similar in fish fed CP0, CPI or PhytI but less (p < 0.05) in other fish. Bone Zn in fish fed C0, Phyt0 or PhytI was higher (p < 0.05) than that in fish fed CP0 or CPI. In conclusion, CP0, CPI and PhytI had the same effect, suggesting phytase pre-treatment as the most effective method. CPI did not have any advantage over CP0. Phytase increased mineral availability and utilization, which would minimize cost of mineral supplementation and discharges into the environment.     

Demonstration of uniformity of calcium absorption in adult dogs and cats

A meta‐analysis was conducted to understand quantitative aspects of calcium (Ca) and phosphorus (P) absorption in adult dogs and cats. 34 studies in dogs and 14 studies in cats met the criteria for inclusion in the meta‐analysis. Intake and faecal excretion values of Ca and P were subjected to a modified Lucas test and subsequent regression analyses. According to the current scientific consensus, Ca true digestibility (absorption) should increase at low Ca intake and decrease at high Ca intake. If true, this should result in a nonlinear relationship between the percentage of Ca excreted and dietary Ca intake. The present meta‐analysis showed a highly significant linear relationship (p < 0.0001) between Ca intake and Ca excretion suggesting a lack of systematic quantitative adaptation in true Ca digestibility. This finding suggests either that the time period covered by standard digestion trials is too short to induce adaptation mechanisms or that dogs and cats at maintenance will not efficiently alter quantitative Ca absorption percentage according to the amount ingested. If the latter is true, a dietary Ca supply differing greatly from the recommended dietary intake might impair the health of cats and dogs when fed long term. The data plots for P intake and faecal excretion were less uniform suggesting other factors not just dietary intake influence faecal P excretion. In adult cats, the dietary Ca:P ratio strongly influenced the true digestibility of P, whereas this effect was less marked in adult dogs. Faecal P excretion was significantly correlated to faecal Ca excretion in both species (p < 0.0001), and surprisingly, the level of P intake did not appear to be an important determinant of true digestibility of P.     

Effect of resistant starch on the intestinal health of old dogs: fermentation products and histological features of the intestinal mucosa

The effects of resistant starch (RS) intake on nutrient digestibility, microbial fermentation products, faecal IgA, faecal pH, and histological features of the intestinal mucosa of old dogs were evaluated. The same formulation was extruded in two different conditions: one to obtain elevated starch cooking degree with low RS content (0.21%) and the other lower starch cooking with high RS content (1.46%). Eight geriatric Beagles (11.5 ± 0.38 years old) were fed each diet for 61 days in a crossover design. Food intake, nutrient digestibility, fermentation products, faecal pH, and faecal IgA were examined via variance analysis. Histological results of intestinal biopsies were assessed via Wilcoxon test for paired data. The morphometric characteristics of large intestine crypts were evaluated via paired t tests (p < .05). Protein, fat, and energy digestibilities were higher for the low‐RS diet (p < .05). Dogs receiving the high‐RS diet had lower faecal pH and higher values for propionate, butyrate, total volatile fatty acids, and lactate (p < .05). No differences between diets were found in the histological parameters of the gut mucosa, and only a tendency for deeper crypts in the descending colon was observed for dogs fed the high‐RS diet (p = .083). The intake of a corn‐based kibble diet manufactured with coarse ground raw material and low starch gelatinization to obtain 1.4% of RS affected microbial fermentation products and faecal pH and tended to increase crypt depth in the descending colon of old dogs.     

Bioavailability of phosphorus in meat and bone meal for swine

Meat and bone meal (MBM), when supplemented with tryptophan, is an excellent protein source for pigs. It is also a rich source of Ca and P, but some research has suggested that the bioavailability of P is variable. Experiment 1 further examined the bioavailability of P in MBM. The MBM was obtained directly from a plant and was processed to pass through a 10-mesh screen. It contained 50.7% CP, 2.26% lysine, 10.0% Ca, and 5.0% P (air-dry basis). Individually penned pigs (n = 35; 17 kg initial BW) were fed (ad libitum basis) a low-P, corn-soybean meal-basal diet (0.95% lysine, 0.70% Ca, 0.34% P; as-fed basis) or the basal with graded levels of added P (0.067, 0.133, 0.200%) from monosodium phosphate (MSP) or MBM for 40 d. The Ca level was 0.70% in all diets. Diets were fortified with salt, vitamins, and trace minerals. At termination, the third and fourth metacarpals and metatarsals and femurs were removed from all pigs. Growth rate and feed:gain improved linearly (P < 0.01) with P addition, regardless of source, whereas ADFI was unaffected (P = 0.20). Bone strength and ash increased linearly (P < 0.01) with increasing level of P from either source. The main effect of P source (MSP vs. MBM) was not significant, except for the greater femur strength (P < 0.05) in the pigs fed the MSP-supplemented diets. Femur and metacarpal/metatarsal strength and metacarpals ash (grams) were regressed on grams of added P consumed for each P source, with the basal included in both regressions. Based on slope ratios (MSP considered as 100%), the relative bioavailability of P in MBM averaged 87% when the regression lines were forced through a common intercept and 95% when unforced. In Exp. 2, 100 pigs were fed fortified corn-soybean meal or corn-soybean meal-MBM diets from 45 to 110 kg BW to evaluate MBM as the sole source of supplemental P. The MBM (54% CP, 2.3% lysine, 9.2% Ca, 4.4% P; air-dry basis) was substituted for corn and soybean meal on a lysine basis, and crystalline lysine was added to all diets at 0.15%. Tryptophan was included in diets containing MBM. Treatments were arranged in a 2 x 2 factorial with P source (dicalcium phosphate or MBM) and P level as the two factors. The two levels of P and Ca were at the NRC requirement or the NRC level plus 0.10% additional P and Ca. Performance, carcass traits, and bone strength were not affected by source of P and Ca, but bone strength was greater (P < 0.01) at the higher P and Ca level. These results indicate that the bioavailability of P in MBM, relative to that in MSP, is high (approximately 91%) for growing pigs, and MBM can serve as the sole source of supplemental P and Ca for finishing pigs.     

Effect of pre‐partum supplementation of vitamin E to Murrah buffaloes on immune functions and viability of calves

This study was undertaken in buffalo neonates born to vitamin E (dl ‐ alpha ‐ tocopherol acetate) ‐ supplemented and non‐supplemented Murrah buffaloes. Calves from vitamin E‐supplemented buffaloes (n = 10; vitamin E ‐supplemented calves [VeC]) and non‐supplemented buffaloes (n = 10; control calves [CC]) constituted the treatment and control groups respectively. Two colostrum samples were taken at the first post‐partum milking and again after 12 h from dams for IgG estimation. Sampling of blood was performed on days 0 (before colostrum feeding), 1, 3, 7, 14, 21, 28, 42, 56, 70, 84, 98, 112 and 126 post‐birth and analysed for apparent efficiency of absorption (%) of IgG and various immune parameters. Colostral IgG level was significantly higher (p < 0.05) in vitamin E‐supplemented buffaloes. The calves in both groups were born hypogammaglobulinemic with IgG level <5 g/l. However, first colostrum feeding resulted in significantly elevated IgG levels (>10 g/l) in calves of both groups at 24 h, which remained high afterwards. Apparent efficiency of absorption (%) of IgG at 24 h was significantly higher (p < 0.05) in VeC than in CC. Plasma Nitric Oxide (NO) levels were significantly elevated in the calves of either group at birth, which declined significantly (p < 0.01) afterwards. Vitamin E feeding to dams had no added effect on NO levels in experimental calves. Total leucocyte counts did not differ significantly between the two groups. However, lymphocyte and neutrophil counts changed significantly between groups (p < 0.01) and days (p < 0.01), with lymphocytes increasing and neutrophils declining with age. This study revealed that the calves were immunologically immature at birth. Ante‐partum supplementation of vitamin E did not influence plasma NO or IgG but had a significant effect on colostral IgG (p < 0.05). It also improved the apparent efficiency of absorption (%) of IgG at 24 h in VeC as compared to CC.     

Effect of Dietary N‐Carbamylglutamate Levels on Reproductive Performance of Gilts

The effect of dietary N‐carbamylglutamate (NCG) supplementation during the entire gestation on reproductive performance of gilts was determined. At the initial day of gestation, forty‐five cross‐bred (Landrace × Large white) gilts were randomly assigned to five groups receiving a basal diet (control group) and basal diet supplemented with 0.05%, 0.10%, 0.15% and 0.20% NCG until parturition, respectively. At parturition, total litter size, live litter size and rate of stillbirth were not markedly affected by NCG supplementation. However, gilts in 0.05% NCG‐supplemented group had more pigs born alive than gilts in control group (+1.11 pigs, p = 0.12), and live litter weight was increased (+12.13–19.17%, p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups relative to control group. And also, average birthweight of piglets born alive was higher (+6.57%, p < 0.05) in 0.05% NCG‐supplemented group than in control group. Furthermore, on days 30, 60, 90 and 110 of gestation, concentrations of arginine and ornithine in plasma were higher (p < 0.05) in 0.05%, 0.10%, 0.15% and 0.20% NCG‐supplemented groups than in control group, respectively. In addition, the chorioallantois gene expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor A (VEGF‐A), placental growth factor (PLGF) and angiopoietin‐2 (ANG‐2) was all increased (p < 0.05) in 0.05%, 0.10% and 0.15% NCG‐supplemented groups than in control group. In conclusion, dietary supplementation with 500 mg/kg NCG during the entire gestation significantly improves pregnancy outcomes in gilts, which may be associated with the improved concentrations of arginine in plasma and placental angiogenic factors gene expression of gilts.     

Effect of type of starch and quantity in rations on apparent and true digestibility of nitrogen and nitrogen balance in sheep

In a digestibility trial 5 semisynthetic rations were fed in 3 periods to 10 male sheep to examine the effects on N balance, components of faecal nitrogen and N digestibility. The rations contained constant amounts of nitrogen but different contents of cellulose and two different types of starch (untreated and steamflaked). Content and type of starch did not show any noticeable effect neither on excretion of undigested dietary nitrogen nor on true digestibility. There could not be noticed any effects on the apparent N digestibility by changing contents of cellulose or untreated starch. If the rations contained steamflaked corn starch, the animals excreted more faecal nitrogen and therefore showed a lower apparent N digestibility. Especially the water soluble N fraction of the faecal nitrogen was clearly higher. Compensation took place through a lower N excretion with the urine. The reason for increased faecal N excretion may be higher microbial protein synthesis in the rumen. This was accented by the allantoin excretion with the urine.     

Correlations between changes in intestinal microbiota composition and performance parameters in broiler chickens

Growing male Cobb broiler chickens were fed on diets supplemented with additives reported as able to influence intestinal microbiota composition. The diets used were a balanced commercial diet (no additive), inulin (20 g/kg), fructose caramel (FC, 20 g/kg) and the garlic derivative PTS‐O (propyl propane thiosulfonate, 45 and 90 mg/kg diet). The composition of the intestinal microbiota was analysed by qPCR at different points of the intestinal tract, and a number of nutritional parameters were also determined. The relative amounts of bacteroides (bacteroides/total bacteria) in the ileal contents correlated (p < 0.05) positively with faecal NDF, ADF, hemicellulose and cellulose digestibility. The relative amounts of Escherichia–Shigella (Escherichia–Shigella/total bacteria) in the crop contents correlated (p = 0.05) negatively with weight gain of broilers. Faecal N digestibility correlated (p < 0.05) negatively with total bacteria in the ileal contents of chickens. The relative amounts of Escherichia–Shigella (Escherichia–Shigella/total bacteria) in the caecal contents correlated (p = 0.05) negatively with faecal fat digestibility of broilers. Total bacteria in ileal or caecal contents of growing chickens correlated (p < 0.05) negatively with ileal N digestibility. The results here reported suggest that positive or negative correlations can be found between performance parameters and changes in intestinal microbiota composition of growing broiler chickens.     

混合挥发性脂肪酸钠盐对羔羊小肠消化酶活性及氮沉积的影响

本文旨在研究混合挥发性脂肪酸钠盐对羔羊小肠食糜消化酶活性及氮沉积的影响.选取15只7周龄、平均体重(13.8±0.8) kg的杂交公羔羊,随机分为5组,每组3只,饲喂代乳料作为基础营养供给.各组分别向代乳料中添加0、5、15、30和60 g/d混合挥发性脂肪酸钠盐(乙酸钠、丙酸钠和丁酸钠的摩尔比为65∶25∶10).试验期为24 d.在试验期的最后4天,收集粪样和尿样,用于测定粪氮和尿氮.试验结束后将羔羊屠宰,收集小肠食糜,测定小肠食糜中的α-淀粉酶、胰蛋白酶、脂肪酶、糜蛋白酶和半乳糖苷酶的活性.结果表明:添加混合挥发性脂肪酸钠盐对小肠食糜pH、胰蛋白酶、脂肪酶、糜蛋白酶和半乳糖苷酶活性均没有显著影响(P＞0.05),对粪氮、尿氮及氮表观消化率也没有显著影响(P＞0.05).30和60 g/d组的α-淀粉酶活性显著低于其他各组(P＜0.05).添加混合挥发性脂肪酸钠盐有增加羔羊氮沉积的趋势(P=0.090).结果提示,向代乳料中添加30～60 g/d混合挥发性脂肪酸钠盐可降低羔羊α-淀粉酶的活性,有增加氮沉积的趋势,但是对小肠胰蛋白酶、脂肪酶、糜蛋白酶和半乳糖苷酶的活性没有显著影响.     

A comparative meta‐analysis on the relationship of faecal calcium and phosphorus excretion in mammals

To investigate the relationship between faecal calcium (Ca) and phosphorus (P) excretion in different mammalian species, a meta‐analysis on digestibility data derived from the literature was conducted. Seventy‐three studies on carnivores, omnivores, large and small hindgut fermenters, ruminants and hippos (a total of 21 mammalian species, precondition for inclusion dietary Ca/P ratio 1.5/1 – 3.0/1) were analysed for Ca and P digestibility. Dietary Ca/P ratios were lower than faecal Ca/P ratios in carnivores, omnivores, ruminants and hippos. In hindgut fermenters, dietary Ca/P ratios were higher than faecal Ca/P ratios, indicating higher intestinal Ca absorption in these species. In all species investigated, there was a significant positive relationship between Ca intake and faecal Ca excretion and between P intake and faecal P excretion. In the biologically relevant range, these equations predicted lower faecal Ca losses in hindgut fermenters than ruminants, for faecal P vice versa. In all species, faecal Ca and P excretion correlated significantly. In carnivores, this highly linear correlation was exceptionally strong (R² = .92). Yet, the linearity of the correlation was questionable in omnivores and ruminants. Possibly, the strong linear correlation of faecal Ca and P excretion in carnivores is due to the formation of insoluble Ca/P complexes in their relatively short and simple gastrointestinal tract. Another hypothesis is that in carnivores, Ca homeostasis relies on modifying bone turnover to a higher degree than on changes in intestinal Ca absorption. For the formation of bone matrix, a constant ratio of Ca and P absorption is of advantage.     

Effects of juniper essential oil on growth performance,some rumen protozoa,rumen fermentation and antioxidant blood enzyme parameters of growing Saanen kids

This study aimed to evaluate the effects of juniper essential oil on the growth performance, rumen fermentation parameters, rumen protozoa population, blood antioxidant enzyme parameters and faecal content in growing Saanen kids. Thirty‐six male Saanen kids (36 ± 14 days of age) were used in the study. Each group consisted of 9 kids. The control group (G1) was fed with a diet that consisted of the above concentrated feed and oat hay, whereas the experimental groups consumed the same diet but with the concentrated feed uniformly sprayed with juniper essential oil 0.4 ml/kg (G2), 0.8 ml/kg (G3) or 2 ml/kg (G4). There were no differences (p > 0.05) in live weight, live weight gain or feed consumption between the control and experimental groups. There was a significant improvement (p < 0.05) in feed efficiency in the G3 group. There were no differences in the rumen pH, rumen volatile fatty acid (VFA) profile or faecal pH of the control and experimental groups. The rumen NH₃N values were similar at the middle and end of the experiment, but at the start of the experiment, the rumen NH₃N values differed between the control and experimental groups (p < 0.05). The faecal score value was significantly (p < 0.05) decreased in the experimental groups. The addition of juniper essential oil supplementation to the rations caused significant effects on the kids’ antioxidant blood parameters. Although the superoxide dismutase (SOD) activity, total antioxidant capacity (TAC) and catalase values were significantly (p < 0.05) increased in the experimental groups (G2, G3 and G4), especially group G4, the blood glutathione peroxidase (GPX) value significantly decreased in the experimental groups. The results of this study suggest that supplementation of juniper oil is more effective on antioxidant parameters than on performance parameters and may be used as a natural antioxidant product.     

In vitro gas formation and fermentation parameters using different substrates and pig faecal inocula affected by bile extract

The effect of bile extract on microbial gas formation and composition, production of volatile fatty acids (VFA) and methane and on reductive acetogenesis was studied in vitro. As substrates cellulose and potato starch in combination with graded levels of bile extract concentrations (0; 333; 666; 1333 mg/l) were incubated with a faecal suspension from pigs as microbial inoculum according to procedures of a modified “Hohenheim gas formation test” (HFT). Bile extract concentration of 1333 mg/l in the in vitro system reduced total gas production from cellulose significantly (p < 0.05) compared to incubation without bile extract. After 24 h of incubation, bile extract concentration of 1333 mg/l lead to a decrease in methane production from cellulose (p < 0.05) in comparison to incubation without bile extract. Increasing levels of bile extract reduced total production of VFA (p < 0.05) from cellulose. Furthermore, bile extract concentration of 1333 mg/l increased molar percentage of propionate from cellulose and starch after 24 h of incubation (p < 0.05). Bile extract concentration of 333 mg/l increased molar percentage of propionate from cellulose after 48 h of incubation (p < 0.05). The results may contribute to explain the differences in gas and methane production between the rumen and the hindgut of monogastric animals.     

Effects of different lipid sources on intake,digestibility and purine derivatives in hair lambs

An experiment was conducted to evaluate the effects of different lipid sources on the nutrient intake, digestibility and purine derivative excretion of lambs. Thirty‐five 60‐day‐old, male, non‐castrated Santa Ines lambs with an initial average body weight (BW) of 13.00 ± 1.80 kg were used in a randomized complete block design with seven blocks and five treatments. The experimental treatments consisted of a control diet without supplemental lipids and four test diets with different lipid supplements, selected according to the degree of ruminal protection from hydrogenation: supplementation, being supplementation with whole cottonseed (WC), supplementation with cashew nut meal (CNM), supplementation with both cottonseed and cashew nut meal (WC‐CNM) and supplementation with calcium salts of long‐chain fatty acids (Ca‐LCFA). The lambs were slaughtered after reaching 28 kg average BW for each treatment. The ether extract intake (EEI) was higher (p < 0.01) for the lipid supplemented compared to control diet lambs. Supplementation with WC decreased the digestibility of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF) and total carbohydrate (TC) (p < 0.01), whereas supplementation with CNM, WC‐CNM and Ca‐LCFA reduced non‐fibrous carbohydrate (NFC) digestibility (p < 0.01). The ether extract (EE) digestibility coefficient was higher with CNM, followed by Ca‐LCFA and WC, when compared to WC‐CNM and control diets. Nitrogen balance (NB) was not influenced (p > 0.05) by the different lipid sources. A lower purine derivative (PD) excretion and thus lower microbial protein supply (MPS) was observed for animals supplemented with Ca‐LCFA (p < 0.01) compared to the WC‐CNM and control diets. In conclusion, WC, CNM and WC‐CNM supplementation did not have negative effects on MPS, although negative effects have been observed on nutrient digestibility.     

The variation in hectolitre weight of wheat grain fed with or without enzyme supplementation influences nutrient digestibility and subsequently affects performance in pigs

A 2 × 2 factorial experiment was conducted to investigate the effect of feeding a wheat‐based diet of two different hectolitre weights (66 vs. 74 kg/hl), achieved through different agronomical conditions, with or without the supplementation of a β‐glucanase and β‐xylanase enzyme mix on young pigs. The parameter categories which were assessed included growth performance, coefficient of apparent total tract digestibility (CATTD), faecal consistency, faecal microbial populations and faecal volatile fatty acid (VFA) concentrations. Sixty‐four pigs (11.6 kg SD 0.97) were assigned to one of four dietary treatments: (T1) low hectolitre weight wheat diet, (T2) low hectolitre weight wheat diet containing 0.1 g/kg β‐glucanase and β‐xylanase enzyme supplement, (T3) high hectolitre weight wheat diet and (T4) high hectolitre weight wheat diet containing 0.1 g/kg β‐glucanase and β‐xylanase enzyme supplement. The inclusion of wheat was 500 g/kg in the diet. The low hectolitre weight grain had a higher level of zearalenone, aflatoxin and ochratoxin contamination compared to the high hectolitre weight grain. The high hectolitre weight wheat had a higher gross energy (GE), crude protein (CP) and lysine contents compared to the low hectolitre weight wheat. Pigs offered the low hectolitre weight diet had a lower average daily gain (ADG) (p < 0.001), a lower gain to feed (G:F) ratio (p < 0.001) and a higher faecal score (more diarrhoea) (p < 0.001) compared to pigs offered the high hectolitre weight. The low hectolitre weight diet had a reduced CATTD (p < 0.05) of nitrogen (N) and gross energy (GE) compared with pigs offered the high hectolitre weight diet. In conclusion, the higher level of mycotoxins and lower content of GE, CP and lysine in the low‐quality wheat reduced ADG and the CATTD of nutrients in pigs offered this diet. The inclusion of a β‐glucanase and β‐xylanase enzyme mix had no effect on growth performance or nutrient digestibility.     

Administration of RRR‐α‐tocopherol to pregnant mares stimulates maternal IgG and IgM production in colostrum and enhances vitamin E and IgM status in foals

This study assessed the effect of a vitamin E supplement given to pregnant mares on immunoglobulins (Ig) levels in foals. In addition, the fatty acid (FA) content and composition of the mares’ milk was assessed. Milk α‐tocopherol concentrations were compared between pregnant Danish Warmblood mares (n = 17) given a daily oral supplement of 2500 international units (IU) RRR‐α‐tocopherol in the last 4 weeks of pregnancy and a group of unsupplemented mares (n = 17) receiving 170–320 IU vitamin E daily originating from the feed. Milk α‐tocopherol was higher in supplemented mares (36.7, 12.4 and 9.8 μmol/l respectively) in relation to control mares (13.1, 6.4 and 5.8 μmol/l on days 1, 2 and 3 respectively; p < 0.001). Milk IgG was higher on days 2 and 3 post‐partum (PP) in supplemented mares (1.03 and 0.73 mg/ml respectively) in relation to control mares (0.79 and 0.56 mg/ml respectively; p < 0.05). Milk IgM was higher on days 2 and 3 post‐partum (PP) in supplemented mares (0.19 and 0.17 mg/ml) in relation to control mares (0.13 and 0.11 mg/ml respectively; p < 0.05). Plasma α‐tocopherol in foals was higher from supplemented mares on days 1, 2 and 3 (5.7, 14.8 and 19.2 μmol/l respectively) in relation to foals from control mares (3.6, 6.1 and 7.6 respectively; p < 0.001). Foal plasma IgM was higher from supplemented mares on day 3 (0.50 mg/ml) in relation to foals from control mares (0.32 mg/ml; p < 0.001). The total FA content in milk was highest on day 1 (21.6 g FA/kg milk) in relation to days 2 and 3 (13.6 and 13.5 g FA/kg milk respectively; p < 0.001). In conclusion, a daily oral supplement of 2500 IU RRR‐α‐tocopherol increased α‐tocopherol content in mare milk and foal plasma, IgG and IgM in mare milk and IgM in foal plasma.     

Effect of organic and inorganic selenium supplementation on semen quality and blood enzymes in buffalo bulls

The present study aimed to evaluate the effect of organic and inorganic selenium (Se) supplementation on semen quality and blood serum profiles of buffalo bulls. Nine mature buffalo bulls were divided into three groups: control (non‐supplemented); organic Se (10 mg Sel‐Plex®/head twice weekly) and inorganic Se (10 mg sodium selenite/head twice weekly). Semen was collected twice a week for 3 months during Se supplementation. Semen properties were evaluated from fresh ejaculate. Moreover, fructose concentration, aspartate and alanine transaminase (AST and ALT) activities, total protein and total cholesterol were assayed in seminal plasma. Additionally AST, ALT, testosterone and Se levels were determined in the blood serum. Results showed that Se supplementation significantly (P < 0.05) influences the semen parameters during 3 months of treatment. Organic Se significantly (P < 0.05) increased the percentage of viable sperms compared to inorganic Se and the control group. Fructose concentration was significantly higher (P < 0.05) in the seminal plasma of organic Se‐treated bulls. Serum testosterone and Se concentrations were significantly (P < 0.05) increased in the Se supplemented groups than the control group. In conclusion, Se supplementation improved the parameters of buffalo bull semen and more precisely, organic Se was more effective for the improvement of semen quality and some blood components than inorganic Se.