Effects of Inulin Chain Length on Fermentation by Equine Fecal Bacteria and Streptococcus bovis

Grass fructans can be fermented by Gram-positive bacteria (e.g., Streptococcus bovis) in the equine hindgut, increasing production of lactic acid and decreasing pH. The degree of polymerization (DP) of fructans has been suggested to influence fermentation rates. The objective of the present study was to determine how DP impacts fermentation by equine fecal bacteria and a model S. bovis. Fecal microbes from three mares were harvested by differential centrifugation, washed, and resuspended in anaerobic media containing short-chain (SC; DP ≤ 10) or long-chain (LC) inulin (DP ≥ 23) from 0% to 2% wt/vol. After 24 hours of incubation (37°C), samples were collected for pH determination. Data were analyzed using the general linear models (GLM) procedure testing for the effect of treatment, concentration, and treatment × concentration (SAS v. 9.3). At all concentrations, the pH was lower in SC fermentations than in LC (P < .0001, in all cases). To determine the effect of DP on S. bovis, cultures were grown (39°C, 9 hours) with 0.1%, 0.5%, or 1.3% SC or LC inulin. Optical density (600 nm) was determined by spectrophotometry. Maximum specific growth rates (μ) were determined by linear regression (2–5 hours). Data were analyzed using the one-way analysis of variance procedure (SAS v. 9.3). The final optical density (600 nm), μ, and yield were higher with SC than with LC fermentation (P < .05). These results indicate that SC inulin may be more available for fermentation than LC inulin by equine fecal bacteria and S. bovis, specifically.     

Impact of zinc and arginine on antioxidant status of weanling piglets raised under commercial conditions

The effects of dietary zinc and L-arginine supplements on the weight gain, feed efficiency, antioxidant capacity and oxidative status of weanling piglets raised under commercial conditions were examined. A total of 288 piglets aged 21 d were fed for 15 d a diet supplemented or not with 2,500 mg/kg of zinc (provided as zinc oxide) and 1% L-arginine·HCl. The 4 treatments were distributed in a randomized complete block design with 6 initial body weight categories (12 animals per pen). Access to feed and water was ad libitum. Data were analyzed as a 2 × 2 factorial experiment using the SAS MIXED procedure, with zinc and arginine as the main independent variables. Blood collection day (d 8 and 15, samples were collected from the same 2 piglets in each pen before the morning feeding) was included as a third factor. The zinc supplement increased the average daily gain (ADG) from d 0 to 7, d 8 to 15 and d 0 to 15 (0.289 vs. 0.217 kg/d), average daily feed intake (ADFI) from d 8 to 15 and d 0 to 15 (0.338 vs. 0.279 kg/d) and the gain to feed (G:F) ratio from d 0 to 7 and d 0 to 15 (0.86 vs. 0.77) (P < 0.001). Both supplements significantly decreased the malondialdehyde concentration (zinc: 4.37 vs. 3.91 μmol/L, P = 0.005; arginine: 4.38 vs. 3.89 μmol/L, P = 0.002). Total antioxidant capacity and reduced glutathione (GSH) increased from d 8 to 15 (0.953 vs. 1.391 μmol/L, 2.22 vs. 3.37 μmol/L, P < 0.05) regardless of dietary treatment. Total and oxidized GSH concentrations on d 8 were higher in response to the combined supplements (zinc × arginine interaction, P < 0.05). Piglets fed either Zn-supplemented diet had a lower haptoglobin serum concentration (509 vs. 1,417 mg/L; P < 0.001). In conclusion, the zinc supplement improved piglet growth performance (ADG and ADFI) and oxidative status (based on malondialdehyde concentration). The arginine supplement had a limited effect on growth performance and oxidative status under these conditions.     

Genetic parameters and trends for production and reproduction traits in Thai Landrace sows

Data from Thai Landrace sows were used to estimate the genetic parameters and trends for production and reproduction traits, over the first four parities. The reproduction traits investigated were age at first conception (AFC), total number of piglets born per litter (TB) and weaning to first service interval (WSI). The reproduction data was gathered from 9194 litters born between 1993 and 2005. The production measures were average daily gain (ADG) and backfat thickness (BF). These were recorded from 4163 boars and 15 171 gilts. Analyses were carried out using a multivariate animal model inputting average information restricted maximum likelihood procedures. Heritability estimates on the reproduction traits for AFC was 0.21, for TB in the first four parities it ranged from 0.02 to 0.11 and for WSI over the first three parities it ranged from 0.16 to 0.18. Heritability estimates for production traits were: 0.31 (ADG) and 0.45 (BF). AFC was genetically correlated favorably with TB (− 0.48) and WSI (0.35) in the first parity. Genetic trends were 4.71 g, − 0.23 mm and 0.23 days per year for ADG, BF and AFC respectively. There was no genetic progress for the other traits. It was concluded that selection for low AFC will increase TB and decrease WSI. The results further revealed that the ongoing selection being used improved growth rate and reduced backfat thickness. However, there was no genetic improvement in TB.     

Dietary xylanase and live yeast supplementation influence intestinal bacterial populations and growth performance of piglets fed a sorghum-based diet

This study was to evaluate the effect of xylanase supplementation and the addition of live yeast, Saccharomyces cerevisiae, on growth performance and intestinal microbiota in piglets. One hundred and eighty commercial crossbred 23-d-old piglets (PIC 417) were sorted by initial BW and allocated to 3 treatments: control (CTR) diet, CTR diet supplemented with xylanase at 16,000 birch xylan units/kg (XYL) and XYL diet supplemented with live yeast (2 × 10¹⁰ CFU/g) at 1 kg/t (XYL + LY). Each treatment had 10 replicates, with 6 animals each. A sorghum-based diet and water were available ad libitum for 42 d of the study. Average daily gain (ADG) and average daily feed intake (ADFI) were measured from 0 to 42 d (23- to 65-d-old) and feed conversion ratio (FCR) calculated. At the end of the study, bacterial identification through 16S rRNA (V3 to V4) sequencing of the ileal and caecal digesta from one piglet per replicate was performed. No treatment effects were observed on ADFI. Pigs offered the live yeast in addition to the xylanase had increased ADG compared with those supplemented with xylanase alone (XYL + LY vs. XYL; P = 0.655). FCR was improved with XYL and XYL + LY compared with CTR (P = 0.018). Clostridiaceae counts in the ileum tended to reduce by 10% with XYL and 14% with XYL + LY compared to CTR (P = 0.07). XYL and XYL + LY increased the counts of Lactobacillaceae in the caecum compared with CTR (P < 0.0001). Dietary supplementation of live yeast combined with xylanase improved growth performance and microbial balance of piglets during the nursery phase.     

Assessment of Antimicrobial Susceptibility of Virulent Strains of Rhodococcus equi Isolated From Foals and Soil of Horse Breeding Farms With and Without Endemic Infections

Rhodococcus equi is an opportunistic, intracellular saprophyte that causes severe pyogranulomatous pneumonia in foals. The bacterium displays in vitro susceptibility to many antibiotics. The highest efficacy against R. equi in vitro and in vivo is achieved by using a combination of rifampicin and macrolide antibiotics. Recent years have seen an upward trend in the minimum inhibitory concentration (MIC) of rifampicin and erythromycin, suggesting increasing resistance of R. equi to these antibiotics. The aim of the study was to determine the antimicrobial activity of 24 selected antibiotics against R. equi strains isolated from dead foals and from the environment of horse breeding farms with and without endemic R. equi infections. Minimum inhibitory concentration gradient strips were used to determine the lowest concentration of the antibiotic that inhibited the growth of R. equi. Based on normal MIC distribution, an epidemiologic cutoff values (ECOFF) were assessed for particular antibiotics and R. equi strains. The results were compared with ECOFFs for S. aureus, according to the European Committee on Antimicrobial Susceptibility Testing data. The data indicate that the lowest MIC values were obtained for clarithromycin, rifampicin, imipenem, and vancomycin. The majority of R. equi strains can be classified as wild type in relation to the majority of antibiotics. A small percentage of strains presented non-WT (NWT) with the exception of SXT, for which 35% of strains were classified as NWT. The lack of interpretative criteria for R. equi creates a real problem in the assessment of antibiotic sensitivity both for clinical and scientific purposes.     

Factors affecting performance response of pigs exposed to different challenge models: a multivariate approach

Factors associated with the severity with which different challenge models (CMs) compromise growth performance in pigs were investigated using hierarchical clustering on principal components (HCPC) analysis. One hundred seventy-eight studies reporting growth performance variables (average daily gain [ADG], average daily feed intake [ADFI], gain:feed [GF], and final body weight [FBW]) of a Control (Ct) vs. a Challenged (Ch) group of pigs using different CMs (enteric [ENT], environmental [ENV], lipopolysaccharide [LPS], respiratory [RES], or sanitary condition [SAN] challenges) were included. Studies were grouped by similarity in performance in three clusters (C1, C2, and C3) by HCPC. The effects of CM, cluster, and sex (males [M], females [F], mixed [Mi]) were investigated. Linear (LRP) and quadratic (QRP) response plateau models were fitted to assess the interrelationships between the change in ADG (∆ADG) and ADFI (∆ADFI) and the duration of challenge. All variables increased from C1 through C3, except for GF, which decreased (P < 0.05). LPS was more detrimental to ADG than ENV, RES, and SAN models (P < 0.05). Furthermore, LPS also lowered GF more than all the other CMs (P < 0.05). The ∆ADG independent of ∆ADFI was significant in LPS and SAN (P < 0.05), showed a trend toward the significance in ENT and RES (P < 0.10), and was not significant in ENV (P > 0.10), while the ∆ADG dependent on ∆ADFI was significant in ENT, ENV, and LPS only (P < 0.05). The critical value of ∆ADFI influencing the ∆ADG was significant in pigs belonging to C1 (P < 0.05) but not C2 or C3 (P > 0.10). The ∆ADG independent of duration post-Ch (irreparable portion of growth) was significant in C1 and C2 pigs, whereas the ∆ADFI independent of duration post-Ch (irreparable portion of feed intake) was significant in C1 pigs only (P < 0.05). Moreover, the time for recovery of ADG and ADFI after Ch was significant in pigs belonging to C1 and C2 (P < 0.05). Control F showed reduced ADG compared with Ct-M, and Ch-F showed reduced ADFI compared with Ch-M (P < 0.05). Moreover, the irreparable portion of ΔADG was 4.8 higher in F (−187.7; P < 0.05) compared with M (−39.1; P < 0.05). There are significant differences in growth performance response to CM based on cluster and sex. Furthermore, bacterial lipopolysaccharide appears to be an appropriate noninfectious model for immune stimulation and growth impairment in pigs.     

Effect of concentrate extrusion and castration on diet digestion and performance of intensively reared male calves

Fifty-six male Friesian calves, half of them castrated, were used to study the effects of concentrate extrusion and animal castration on diet digestibility and performance in two different growth phases (from 91 to 250 and from 250 to 400 kg live weight). Diets consisted of a compound meal, extruded or nonextruded, and barley straw, both of them fed ad libitum. Half of the animals were slaughtered at 250 kg and the remaining at 400 kg live weight. Extrusion increased the gelatinization grade, resulting in a higher (p<0.01) fermentation rate, and reduced nitrogen solubility and degradation after 12 h of rumen incubation (p<0.05). Calves receiving the extruded meal showed a lower rumen ammonia concentration just before the first meal (p<0.001), the differences disappearing afterwards. Neither the pH nor the total VFA concentrations were affected, although butyrate, isobutyrate and isovalerate proportions before the first meal decreased with the extruded diet. Concentrate extrusion did not affect the apparent OM digestibility of total diet but caused a reduction of NDF (p<0.01) and CF (p<0.05) digestibility. In the first growth phase, concentrate and total DM intake decreased with extrusion (p<0.001), without affecting the average daily gain (ADG). Consequently, the concentrate and total feed conversion ratios were significantly lower (p<0.001 and p<0.01, respectively) with the extruded meal. Bulls showed a higher ADG than steers (p<0.001), resulting in lower feed conversion ratios (p<0.01) given that intake was not affected by castration. In the second growth phase, extrusion did not affect any of the performance parameters, however bulls showed a higher DM intake and ADG (p<0.05), but no differences in the feed conversion ratio were found between entire and castrated animals.     

Reduced dietary nitrogen with a high Lys:CP ratio restricted dietary N excretion without negatively affecting weaned piglets

We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen (N) pollution associated with animal husbandry. Two experiments (45 d each experiment) were performed on weaned piglets (Duroc × Landrace × Yorkshire, 28 d of age) to test this and to determine the optimal lysine to crude protein (Lys:CP) ratio in diet. In Exp. 1, 12 piglets (6 replicates [n = 6]) were fed diets containing different levels of CP (17% and 20%) but the same level of Lys. Increased CP content resulted in significant increases (P < 0.05) of average daily gain (ADG), average daily feed intake (ADFI), and body weight (BW), but did not affect the feed to gain ratio. In Exp. 2, 24 piglets (8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio (6.23%, control); 2) 17% CP with a reduced Lys:CP ratio (6.14%, LL); or 3) 17% CP with a standard Lys:CP ratio (7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance, intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.     

Evaluation of increased fiber,decreased amino acids,or decreased electrolyte balance as dietary approaches to slow finishing pig growth rates

In swine production, pig movement restrictions or packing plant closures may create the need to slow growth rates of finishing pigs to ensure they remain at a marketable body weight when packing plant access is restored. Although dietary formulations can be successful at slowing pig growth, precision is needed regarding how to best formulate diets to achieve growth rate reductions. Thus, the objective was to evaluate three dietary experimental approaches aimed at slowing growth rates in finishing pigs. These approaches consisted of either increasing neutral detergent fiber (NDF), reducing essential amino acids, or reducing the dietary electrolyte balance through the addition of acidogenic salts. A total of 94 mixed-sex pigs (72.4 ± 11.2 kg BW) across two replicates were individually penned and assigned to 1 of 8 dietary treatments (n = 11–12 pigs/treatment): 1) Control diet representative of a typical corn–soybean meal-based finisher diet (CON); 2) diet containing 15% NDF from soybean hulls (15% NDF); 3) diet containing 20% NDF from soybean hulls (20% NDF); 4) diet containing 25% NDF from soybean hulls (25% NDF); 5) diet formulated as per CON but with 50% of the soybean meal replaced with corn (89% Corn); 6) diet containing 97% corn and no soybean meal or synthetic amino acids (97% Corn); 7) diet containing 2% anhydrous calcium chloride (2% CaCl₂); and 8) diet containing 4% anhydrous calcium chloride (4% CaCl₂). Over 28 d, pig body weights and performance were recorded weekly. At d 28, all pigs were ultrasound scanned and switched to the CON diet to evaluate compensatory gain from d 28 to 35. Overall, increased NDF did not impact any growth performance parameter (P > 0.05). Amino acid restriction reduced average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) linearly (linear P < 0.001). Similarly, ADG, ADFI, and G:F were linearly reduced with increased CaCl₂ inclusion (linear P < 0.001). ADG differed during the compensatory gain period (P < 0.001), with 4% CaCl₂-fed pigs having a 47% increase in ADG compared with CON-fed pigs. Conversely, 15% and 25% NDF-fed pigs had reduced ADG compared with CON-fed pigs during the compensatory gain period. Gain efficiency differed from day 28 to 35 (P < 0.001), with 4% CaCl₂-fed pigs having a 36% increase in G:F compared with CON-fed pigs. Altogether, these data demonstrate that both amino acid restriction and CaCl₂ inclusion are effective at slowing pig growth, albeit at greater inclusion rates.     

Effect of dietary concentrate content on feed intake,feed efficiency,and meat quality of Holstein steers fattened in a hot environment

The objective of this study was to investigate the effect of feeding high and low concentrate diets on feed intake and feed efficiency, the morphological characteristics of the rumen papillae, and meat quality of Holstein steers fattened under hot climate conditions in Oman. Ten male Holstein calves, of 5 months of age, were selected for the experiment. The animals were fed concentrate and Rhodes grass hay and were divided into two groups of high concentrate (HC, n = 5) and low concentrate diets (LC, n = 5), in which their feed intake, weight gain, and feed efficiency were evaluated across three growing periods. Feed intake and efficiency and average daily gain (ADG) of the HC group were significantly greater than for the LC group and were affected by the diet (p < .01) and the period (p < .001). Across the fattening periods, ADG declined in both groups, with ADG improved by 35% for steers on the HC diet compared to steers on the LC diet. Carcass meat quality was not affected significantly by the dietary concentrate level. In conclusion, our results can be used to make improvements in feed efficiency of Holstein steers under hot climate conditions.     

Effect of quantitative feed restriction on broiler performance

The objective of the current study was to determine the effect of quantitative feed restriction on the performance of broilers. A total of 270 unsexed broilers were randomly allocated to three treatments: with no feed restriction (T1), one week (T2) and two (T3) weeks of feed restriction from 22 days of age and then fed ad libitum until the age of 42 days. Treatments were replicated three times with 30 birds per replicate. Birds were fed with starter, grower and finisher diets. The feed consumed and body weights were recorded every week from the third to the sixth week. The average daily gain (ADG), average daily feed intake (ADFI) and the feed conversion ratio (FCR) were computed for each week. At Week 6, body weights of T3 birds were similar (P > 0.05) to those of T1 and T2 birds. There were also no treatment effects on the ADG at Week 6. In addition, no treatment effects (P > 0.05) were observed on ADFI at each stage of growth. Since ADFI and FCR were similar among the three groups, it was concluded that feed restriction by limiting the time to eat was not successful. There was also no evidence of compensatory growth in the restricted groups.     

Effect of the gain rate during growing phase on the performance and characteristics of carcass and meat of super precocious steers

The aim was to evaluate the effect of different rates of weight gain during the backgrounding on animal performance and carcass and meat characteristics of steers finished in feedlots. Thirty-six Angus steers, 12 ± 2 months of age, were backgrounded during 91 days on Aruana grass pasture (Panicum maximum cv. Aruana) managed under different stocking rates to achieve three different weight gains: HIGH ADG (average daily gain)—no feed restriction (ADG = 0.846 kg); MEDIUM ADG—moderate feed restriction (ADG = 0.456 kg); and LOW ADG—high feed restriction (ADG = 0.154 kg). To ensure the difference in ADG, we offered 0.7% live weight of concentrate feed in the HIGH treatment and a better forage supply in the MEDIUM treatment. After the backgrounding, the animals were finished in feedlot. There was no effect of the previous performance on the animals' performance in the feedlot. The LOW presented higher weight (218.9 vs. 207.9 kg) and hot (54.0% vs. 51.3%) and cold (53.5% vs. 50.5%) carcass yield than the MEDIUM, besides presenting meat with less cooking losses (15.0% vs. 18.2%), marbling (7 vs. 4.0 points), palatability (7.1 vs. 6.3 points), juiciness (7.2 vs. 6.4 points), tenderness (7.1 vs. 6.3 points), and lower shear force (5.78 vs. 8.75 kg) than HIGH. LOW ADG steers stay longer in the finishing phase but presented in general better quality carcass and meat than those with MEDIUM or HIGH during the backgrounding.     

Antithrombin: Could It be a Diagnostic and Prognostic Marker in Septic Neonatal Foals?

Antithrombin (AT) levels are lower in human neonates affected by sepsis and in nonsurvivors compared with survivors. The aims of this study were to evaluate AT profile in healthy newborn foals and its diagnostic and prognostic role in septic foals during the first week of life. Fifteen healthy foals and 35 septic foals were enrolled. Blood samples were collected from each healthy foal at 30 minutes, 3 and 12 hours from birth, daily from days 1–7, and at days 10 and 14. Blood was collected from each septic foal twice a day from admission to discharge or death. The AT analysis was performed by chromogenic method. Healthy foals showed decreasing levels of AT between 3 hours and 2 days, followed by an increasing trend. Septic foals did not show any difference during the period of observation, and no differences were found between healthy and septic age-matched foals. The analysis of AT activity on the day of admission in septic foals showed higher levels compared with healthy foals, in animals hospitalized at 12 and 24 hours of age (P < .01). No differences were found at admission between foals affected by sepsis and that with septic shock. Nonsurviving foals showed significantly lower levels at 3 and 4 days of age compared with surviving foals; when surviving and nonsurviving foals were compared independently by the age, nonsurviving foals showed significant (P < .05) lower levels 12 hours after admission. In conclusion, AT seems to show neither a diagnostic nor a prognostic role in septic neonatal foals.     

Influence of dietary slow‐release urea on growth performance,organ development and serum biochemical parameters of mutton sheep

Eighty Dorper × thin‐tailed Han cross‐bred non‐castrated male lambs [mean body weight (BW), 25.87 ± 1.06 kg] were randomly allocated to one of five different concentrations of slow‐release urea (urea phosphate, UP). The feed consisted of an equal amount of concentrate diet and roughage; the concentrate feed was formulated to be isoenergetic and isonitrogenic and contained 0%, 1%, 2%, 4% and 8% UP (UP0.0, UP1.0, UP2.0, UP4.0 and UP8.0, respectively) as a replacement for soya bean meal. Feed intake, BW, average daily gain (ADG), feed utilisation efficiency (FUE), absolute and relative organ weights and biochemical and histopathological parameters were measured. Feed intake, BW, ADG and FUE significantly decreased in the group receiving UP8.0 (p < 0.05), but no difference was found among the other groups (p > 0.05). Quadratic equations were developed between the UP dosage in the concentrate feed and ADG or FUE (r² = 0.973 for ADG and r² = 0.761 for FUE) to determine the appropriate dosage of UP given the desire to maximise either ADG or FUE, the appropriate dosage (feed concentration) was calculated as 2.01% UP to achieve the greatest ADG or 2.13% UP to achieve the best FUE. The relative weight of the liver (% BW) in the UP2.0 groups was significantly greater than that of UP0.0 (p < 0.05), and the relative weight of the intestine in the UP8.0 was significantly greater than that of UP0.0 (p < 0.05); the relative weight of the carcass, heart, spleen, lung, kidney, rumen, reticulum, omasum and abomasum did not differ among treatments (p > 0.05). The UP8.0 treatment significantly increased serum phosphorus levels (p < 0.05) and decreased the levels of alkaline phosphatase, glucose and calcium (Ca) compared with the lower UP dosage (p < 0.05). No histopathological differences were found in either hepatic tissues or renal tissues among treatments. Dietary UP as a replacement for soya bean in concentrate feeds for mutton sheep should not exceed 4%, as higher dosing may cause malnutrition and mineral disorders.     

Functionality of a next generation biosynthetic bacterial 6-phytase in enhancing phosphorus availability to weaned piglets fed a corn-soybean meal-based diet without added inorganic phosphate

The utility of a next generation biosynthetic bacterial 6-phytase (PhyG) in restoring bone ash, bone phosphorus (P) content and performance in piglets depleted in P was evaluated. A total of 9 treatments were tested as follows. Treatment 1, a negative control (NC) diet; treatments 2, 3, 4, NC supplemented with 250, 500 or 1,000 FTU/kg of PhyG; treatments 5, 6, NC supplemented with 500 or 1,000 FTU/kg of a commercial Buttiauxella sp phytase (PhyB); treatments 7, 8, 9, NC supplemented with monocalcium phosphate (MCP) to provide 0.7, 1.4 and 1.8 g/kg digestible P, equating to a digestible P content of 1.8, 2.5 and 2.9 g/kg. The latter constituting the positive control (PC) diet with adequate P and calcium (Ca). The NC was formulated without inorganic P (1.1 g digestible P/kg) and reduced in Ca (5.0 g/kg). Additional limestone was added to treatments 7 to 9 to maintain Ca-to-P ratio between 1.2 and 1.3. A total of 162 crossed Pietrain × (Large White × Landrace) 21-d-old piglets (50% males and 50% females) were fed adaptation diets until 42 d old and then assigned to pens with 2 pigs/pen and 9 pens/treatment in a completely randomized block design. Piglets were fed mash diets based on corn and soybean meal ad libitum for 28 d. At the end of the study, one piglet perpen was euthanized and the right feet collected for determination of bone strength, bone ash and mineral content. Compared with the PC, the NC group had reduced average daily gain (ADG) and increased feed conversion ratio (FCR) during all growth phases and overall, and at d 28 (70 d old) NC pigs had bones with reduced ash, Ca and P content (P < 0.05). The PhyG at 250 FTU/kg improved bone ash vs. NC. Increasing PhyG dose linearly or quadratically improved bone ash, ADG and FCR (P < 0.05). At ≥ 500 FTU/kg, both PhyG and PhyB maintained ADG and FCR equivalent to PC. Linear regression analysis was done to compare the measured response parameters to increasing digestible P from MCP. Based on this analysis it was shown that PhyG and PhyB at 1,000 FTU/kg could replace 1.83 and 1.66 g/kg digestible P from MCP in the diet, respectively, on average across metacarpi bone ash, ADG or FCR. These findings suggest that the biosynthetic phytase is highly effective in the tested dietary setting.     

Productive performance of weanling piglets was improved by administration of a mixture of bacteriophages,targeted to control Coliforms and Clostridium spp. shedding in a challenging environment

This study was conducted to investigate the effects of bacteriophages in different environments on growth performance, digestibility, ileal and caecal microbiota, gut morphology and immunity of weanling pigs. Two hundred piglets were randomly assigned to four treatment groups with five replicate pens with 10 pigs per pen. A 2 × 2 factorial arrangement of treatments was used to investigate the response of weanling pigs to supplemental bacteriophages (0 and 1.0 g/kg of diet) in contaminated or hygienic environments. Bacteriophages supplementation did not affect average daily gain (ADG), average daily feed intake (ADFI) and gain:feed in phases I and III; however, there was a significant improvement in ADG and gain:feed in phase II. The supplementation of bacteriophages increased the overall gain:feed of pigs. The overall result showed a greater ADG and ADFI in hygienic room. There were reductions in population of both ileal (p < 0.05) and caecal (p < 0.01) Clostridium spp. and ileal coliforms (p < 0.01) with the inclusion of bacteriophages in the diet. Bacteriophages increased ileal Lactobacillus and caecal Bifidobacterium and tended to increase ileal Bifidobacterium (p = 0.08). Contaminated environment decreased ileal Lactobacillus and caecal Bifidobacterium and tended to increase ileal Clostridium (p = 0.08) and coliforms (p = 0.08). Total anaerobic bacteria was tended to decrease (p = 0.06) in contaminated environment. Jejunal villus height increased in pigs received bacteriophages, but they did not affect other morphological items. The interaction between bacteriophages and environment tended to be significant (p = 0.06) for ileal villus height and ileal villus height to crypt depth ratio. The overall faecal score was significantly greater in hygienic environment and bacteriophages groups. The present findings indicate that there is an interactive effect on feed efficiency between bacteriophages and contaminated environment. In addition, bacteriophages improve jejunum morphology, and intestinal microbiota of pigs.     

Dietary lysine requirement for 7–16 kg pigs fed wheat–corn–soybean meal‐based diets

Two experiments were conducted to determine the lysine requirement of weaned pigs [Duroc × (Yorkshire × Landrace)] with an average initial BW of 7 kg and fed wheat–corn–soybean meal‐based diets. The experiments were conducted for 21 days during which piglets had free access to diets and water. Average daily gain (ADG), average daily feed intake (ADFI) and gain to feed ratio (G:F) were determined on day 7, 14 and 21. Blood samples were collected on day 0 and 14 to determine plasma urea nitrogen (PUN) concentration. In experiment 1, 96 weaned pigs were housed four per pen and allocated to four dietary treatments with six replicates per treatment. The diets contained 0.99%, 1.23%, 1.51% and 1.81% standardized ileal digestible (SID) lysine, respectively, corrected analysed values. The rest of the AA were provided to meet the ideal AA ratio for protein accretion. Increasing dietary lysine content linearly increased (p < 0.05) ADG and G:F. In experiment 2, 90 piglets were housed three per pen and allocated to five dietary treatments with six replicates per treatment. The five diets contained 1.03%, 1.25%, 1.31%, 1.36% and 1.51% SID lysine, respectively, corrected analysed values. Increasing dietary lysine content linearly increased (p < 0.05) G:F, linearly decreased (p < 0.05) day‐14 PUN and quadratically (p < 0.05) increased ADG and ADFI. The ADG data from experiment 2 were subjected to linear and quadratic broken‐lines regression analyses, and the SID lysine requirement was determined to be 1.29% and 1.34% respectively. On average, optimal dietary SID lysine content for optimal growth of 7–16 kg weaned piglets fed wheat–corn–SBM‐based diets was estimated to be 1.32%; at this level, the ADG and ADFI were 444 and 560 g, respectively, thus representing an SID lysine requirement, expressed on daily intake basis as, 7.4 g/day or 16.76 mg/g gain.     

Effect of yeast supplementation on the growth performance of Malpura lambs

Thirty-six Malpura lambs (age?=?58 days; 8.9 kg BW) were equally divided into three groups (N?=?12; six males and six females) to assess the effect of probiotics supplementation on growth, digestibility, rumen fermentation and carcass attributes. The lambs of the control group (CON) were not supplemented with probiotics, while test groups received either Saccharomyces cerevisiae (SC) or combination of S. cerevisiae and Lactobacillus sporogenes (SCLS) at 1.5 % of concentrate mixture. The lambs were fed ad libitum concentrate mixture and bajra (Pennisetum typhoides) straw in a cafeteria system until 180 days of age. Daily feed intake and weekly live weight changes were recorded. A metabolism trial was conducted on six lambs at 90 days. Rumen fermentation study was conducted at 105 days. At 6 months, all male lambs were slaughtered and carcass characteristics were recorded. Body weight and average daily gain (ADG) were similar among the three groups. The digestibilities of all the nutrients were also similar among the groups, except acid detergent fiber (ADF) digestibility, which was higher (P?=?0.032) in SC and SCLS than the CON. The rumen fluid pH was higher (P?=?0.04) in CON and SC group than SCLS at 0 h while NH₃-N at 8 h sample was higher (P?=?0.031) in SC and SCLS group than the control. Pre-slaughter weight, hot carcass weight and dressing yields were similar. ADF digestibility and rumen fermentation was improved in lambs by probiotic supplementation. However, carcass traits remained unchanged due to probiotics supplementation.     

Effects of Live Yeast (Saccharomyces cerevisiae Strain 1026) Supplementation on the Closure of Articular Growth Plates in Quarter Horse Foals

To avoid osteoarticular injury and to minimize farm losses in animal use and sales, breaking in young horses is ideally done as soon as growth plates have closed. An experiment was performed to determine whether dietary live yeast could shorten the time for growth plate closure. Twenty-four female Quarter Horse foals, 8 months of age, were allotted to two treatment groups (12 animals each) in a completely randomized experimental design. Horses were fed 0 or 20 g live yeast daily from 8 to 24 months of age. Diets were regular for a stud farm in the area of the study in Argentina. Foals at 8 months of age had a low baseline calcium urinary fractional excretion compatible with a primary calcium-deficient diet for this age in Argentina. Growth plate closure was evaluated by dorsum–palmar radiographs at baseline. A second evaluation was performed when foals were 12 months of age and a third evaluation when foals were 24 months of age. Blood and urine were sampled simultaneously at the same intervals to evaluate bone and mineral metabolism parameters (serum phosphorus, calcium, magnesium; alkaline phosphatase; and hydroxyproline). Calcium, magnesium, and phosphorus urinary fractional excretions were also calculated. Closure scales of distal radius growth plate data were compared using Wilcoxon test and bone markers were compared using Student t-test. Baseline radiological evaluation of growth plates showed that in 84% of foals, the distal metacarpi were either half closed or fully closed at 8 months; therefore, subsequent evaluations were limited to the distal radius. After 4 months of supplementation with live yeast at 12 months of age, a positive but nonsignificant elevation in calcium urinary fractional excretion was observed. At 24 months of age, radiographs showed a nonsignificant but positive effect in the live yeast group, with more than 50% of foals having closed distal radius growth plates. Although bone markers at 24 months of age did not differ (P > .05) between groups, some individual horses showed a positive effect with yeast supplementation.     

No effect of moderate or high concentrate allowance on growth parameters in weanling Warmblood foals fed late‐cut haylage as forage

Two groups of Warmblood foals from the Bavarian federal stud participated in the study beginning from the age of approximately 6 months. The foals were offered a late 1st cut of haylage, oats and foal starter feed. For 2 months after weaning, group ‘R’ (15 foals) received an amount of oats to provide a total digestible energy supply meeting the recommendations of the German Society of Nutrition Physiology (GfE), whereas the other group ‘A’ (16 foals) was offered a higher amount of oats (surplus of approximately 1.3 kg/animal/day). Concentrates were fed individually twice daily; total daily haylage intake of all foals together was recorded. In both groups, individual concentrate intake, body weight (BW), body condition score (BCS) and several growth parameters were documented. Both groups showed an absolutely parallel development of the measured growth parameters and of BW and BCS. BW and BCS increased above the recommendations of GfE and Hois. The amount of concentrates offered was not ingested completely in both groups. The average metabolisable energy (ME) intake from concentrates amounted to 30.3 and 32.1 MJ ME/animal/day (group ‘R’) and 38.7 and 38.2 MJ ME/animal/day (group ‘A’) for the 7th and 8th month respectively. The mean haylage intake of all foals together equalled 26.2 MJ ME/animal/day. The parallel development of all documented growth parameters in both groups leads to the assumption that higher concentrate intake must have caused lower intake of haylage and vice versa, thus resulting in an overall comparable energy intake for each foal, independently of energy source. The calculated average daily energy intake for all foals together amounted to 60.5 and 61.4 MJ ME/animal for the 7th and 8th month. The mean crude protein intake in both groups together amounted to 640 and 647 g/animal/day for the 7th and 8th month.