Efficiency of inorganic and organic iron sources under iron depleted conditions in broilers.

A total of 240 d-old male Ross chicks (average BW 37·15 ± 0·49 g) were fed on an iron (Fe)-deficient semi-synthetic diet (45 mg Fe/kg) from d 1-7 post hatching. At d 7, all 240 chicks (average BW 140·15 ± 1·4 g) with depleted Fe-stores were randomly assigned to three treatments on the basis of BW to study the efficiency of dietary inorganic and organic iron (Fe) utilisation. Each treatment had 4 replicates with 20 birds in each. Dietary treatments were: maize-soyabean meal-based basal diet, containing 103 to 106 mg Fe/kg (control); and basal diets supplemented with an additional 80 mg/kg Fe either from an inorganic (FeSO4 · H2O, 28% Fe) or organic (ferrous methionine chelate, 10% Fe) source. The starter and finisher diets were fed from d 7 to 21 and d 21 to 35, respectively. Improved body weight gain and FCR during finisher phase and overall study period; and greater DM and CP retention, and excreta Fe excretion, at d 20 to 21 and d 34 to 35; were observed in birds fed on Fe supplemented diets when compared with birds fed on control diet. At d 35, the RBC, Hb, haematocrit, and Fe concentration in plasma, tibia and liver were higher in birds fed on Fe supplemented diets than birds fed on the control diet. Supplementation of Fe in organic form resulted in greater Fe concentration in the tibia and liver and less Fe excretion at d 34 to 35, when compared with birds receiving inorganic Fe. These results indicate the necessity to supplement Fe in the commercial diets of broilers; however, organic and inorganic sources of Fe supplementation at 80 mg/kg were equally effective in improving performance, nutrient retention and haematological indices. In addition, Fe supplementation through an organic source seems to be more efficient in depositing Fe in the haemopoietic organs (liver and tibia) of birds under Fe depleted conditions.

Effect of potential multimicrobe probiotic product processed by high drying temperature and antibiotic on performance of weanling pigs.

In this study, the effect of a potential multimicrobe probiotic subjected to high-temperature drying was investigated. Potential multimicrobe probiotics produced by solid substrate fermentation were dried at low (LT, 40°C for 72 h) or high (HT, 70°C for 36 h) temperature. In Exp. 1, 288 weaned pigs (BW, 6.43 ± 0.68 kg) were allotted to 4 treatments on the basis of BW (4 pens per treatment with 18 pigs in each pen). Dietary treatments were negative control (NC; basal diet without any antimicrobial), positive control (PC; basal diet + 0.1% chlortetracycline), basal diet with 0.3% probiotic LT, and basal diet with 0.3% probiotic HT. Diets were fed in 2 phases, phase I (d 0 to 14) and phase II (d 15 to 28); and growth performance, apparent total tract digestibility (ATTD, d 28), and fecal microflora (d 14 and 28) were evaluated. Over the 28-d trial, pigs fed PC and probiotic diets had greater ADG (P < 0.001), ADFI (P < 0.05), and G:F (P < 0.01) than pigs fed NC diet. The ATTD of DM and GE was greater (P < 0.05) in pigs fed probiotic diets when compared with pigs fed the NC diet. At d 28, fewer Clostridia (P < 0.01) were identified in the feces of pigs fed PC and probiotic diets than pigs fed the NC diet. However, the performance, ATTD of DM and GE, and fecal Clostridia population were similar among pigs fed probiotic LT and HT diets. In Exp. 2, 288 weaned pigs (initial BW, 5.84 ± 0.18 kg) were allotted to 4 treatments in a 2 × 2 factorial arrangement on the basis of BW. The effects of 2 levels of probiotic HT (0.30 or 0.60%), each with or without antibiotic (chlortetracycline, 0 or 0.1%), on performance, ATTD, intestinal morphology, and fecal and intestinal microflora were investigated. Feeding of 0.60% probiotic HT diet improved (P < 0.05) overall ADG, ATTD of DM and GE, and Lactobacillus population in the feces and intestine, and reduced the population of Clostridium and coliforms in feces (d 14) and ileum. Inclusion of antibiotic improved (P < 0.05) the overall ADG, ADFI, and ATTD of DM at d 14 and reduced fecal Clostridium population at d 28. Increased (P < 0.05) villus height at jejunum and ileum, and villus height:crypt depth at the ileum was noticed in pigs fed 0.60% probiotic HT and antibiotic diets. In conclusion, high drying temperature had no effect on the efficacy of potential multimicrobe probiotic product. However, the probiotic product dried at high temperature was more effective at 0.60% inclusion, whereas inclusion of an antibiotic improved pig performance but did not show any interaction with probiotics.

Effects of dietary glucose inclusion on reproductive performance, milk compositions and blood profiles in lactating sows.

Twenty-four multiparous sows were used to investigate the effects of dietary glucose inclusion on reproductive performance, milk compositions, blood metabolites and hormones during lactation. The sows were randomly assigned to four treatments and each treatment had six replicates (sows). The diets were added with 0%, 1%, 3% or 5% glucose at the expense of corn and fed to sows for 24 days. The loss of backfat thickness during lactation was quadratically decreased (p = 0.008) and the wean-to-oestrus interval was shortened (linear, p = 0.013; quadratic, p = 0.009) with increasing levels of dietary glucose supplementation. The reproductive performance was not affected (p > 0.05) by different dietary glucose contents. Increased concentrations of total solid and fat in milk were noted (p < 0.05), whereas there was no difference on colostrum compositions. With increasing levels of dietary glucose inclusion, the concentrations of blood urea nitrogen (p = 0.004) and glucose (p = 0.029) were linearly increased at weaning. The concentrations of insulin were increased at post-farrowing (linear, p = 0.027; quadratic p = 0.013) and weaning (linear, p = 0.029; quadratic, p = 0.017), respectively. Furthermore, the pulses of insulin and FSH at weaning were linearly (p = 0.049) and quadratically (p = 0.015) increased with the increasing levels of dietary glucose inclusion. In conclusion, this study indicated that inclusion of 3% glucose in lactating diet could reduce backfat loss, increase milk fat and have no negative effect on reproductive performance in multiparous sows.

Effects of mannanase and distillers dried grain with solubles on growth performance, nutrient digestibility, and carcass characteristics of grower-finisher pigs.

Four experiments were conducted to determine the effects of dietary supplementation of corn distillers dried grain with solubles (DDGS) diets with mannanase on performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, and carcass characteristics of grower-finisher pigs. In Exp. 1, 96 grower pigs (initial BW, 57.6 kg), 6 pigs per pen and 4 pens per treatment, were fed corn-soybean meal-based diets containing 10% DDGS and 0, 200, 400, or 600 units (U) of mannanase/kg. The ADG and blood glucose increased (linear, P < 0.05) with increasing concentrations of dietary mannanase. Pigs fed diets containing increasing levels of mannanase had improved ATTD of DM and CP (quadratic, P < 0.05). In Exp. 2, 64 finisher pigs (initial BW, 92.7 kg) were allotted to 4 treatment groups with 4 pigs per pen and 4 pens per treatment. Pigs were fed corn-soybean meal-based diets containing 15% DDGS and 0, 200, 400, or 600 U of mannanase/kg. Linear increases (P < 0.05) in ADG, blood glucose, and ATTD of DM, GE, and CP were observed with increasing levels of dietary mannanase supplementation. In Exp. 3, 208 grower pigs (initial BW, 60.5 kg) were allotted to 4 treatment groups with 13 pigs per pen and 4 pens per treatment. Pigs were fed diets containing 0 or 10% DDGS and 0 or 400 U of mannanase/kg in a 2 x 2 factorial arrangement. An increase (P < 0.05) in ADG and blood glucose for pigs fed diets containing mannanase was observed. The ATTD of DM and CP (P < 0.05) was decreased with the inclusion of DDGS, whereas pigs fed the mannanase-supplemented diets had an increased (P < 0.05) ATTD of CP. In Exp. 4, 208 finisher pigs (initial BW, 86.5 kg), with 13 pigs per pen and 4 pens per treatment, were fed diets containing 0 or 15% DDGS and 0 or 400 U of mannanase/kg in a 2 x 2 factorial arrangement. The ADG and blood glucose increased (P < 0.05) when mannanase was included in the diets. The ATTD of DM (P < 0.05), GE (P < 0.10), and CP (P < 0.05) increased by the supplementation with mannanase in the diets of finisher pigs. The carcass characteristics and meat quality were not affected by the DDGS or mannanase inclusion. These results indicated that including 10 and 15% DDGS in conventional swine grower and finisher diets had no detrimental effects on growth performance or carcass characteristics. In addition, supplementation with 400 U of mannanase/kg to diets containing 10 and 15% DDGS fed to grower and finisher pigs may improve growth performance and the ATTD of CP.

Potato (Solanum tuberosum L. cv. Gogu valley) protein as an antimicrobial agent in the diets of broilers.

Two experiments were conducted to evaluate potato protein (PP, experiment 1) and refined PP (RPP, experiment 2) obtained from Gogu valley tubers as an antimicrobial agent in broiler diets. In both the experiments, 1-d-old male Ross 308 chicks were allotted to 5 treatments and performance, nutrient retention, and microbial populations in excreta and cecum were studied. Dietary treatments were as follows: basal diet (negative control, NC), basal diet with antibiotic (positive control, PC, 10 mg/kg of avilamycin), and low, medium, or high levels of PP (0.25, 0.50, and 0.75%, respectively, in experiment 1) or RPP (200, 400, and 600 mg/kg, respectively, in experiment 2). The overall gain and retention of DM (d 20 to 21) and CP (d 20 to 21 and d 41 to 42) were greater in birds fed PC and high PP diets than birds fed the NC diet. Population of total aerobic bacteria and coliforms was lowest in the cecum and excreta of birds fed the PC diet and highest in birds fed the NC diet. An increase in dietary PP linearly improved BW gain, feed intake, and feed conversion ratio during starter phase and overall BW gain. Also, there was linear improvement in retention of DM (d 20 to 21) and CP (d 20 to 21 and d 41 to 42) and reduced populations of total aerobic bacteria and coliforms in the cecum (d 42) and excreta (d 28 and 42) due to an increase in dietary PP. In the second experiment, the PC diet and diets with increasing levels of RPP had no effect on performance and nutrient retention. Birds fed the PC diet had the lowest microbial population in excreta and cecum, whereas the population of total aerobic bacteria and coliforms in excreta and cecum decreased (linear, P < 0.05) as the level of RPP was increased in the diet. These results suggest that both PP and RPP obtained from Gogu valley potato tubers have in vivo antimicrobial activity.

Potato (Solanum tuberosum L. cv. Gogu valley) protein as a novel antimicrobial agent in weanling pigs.

A total of 280 weaned pigs (Landrace x Yorkshire x Duroc) were used in a 28-d growth study to investigate the effect of feeding different levels of potato proteins on growth performance, nutrient digestibility, immune response, small intestinal morphology, and bacterial populations in feces and large intestine. Pigs (initially 6.42 +/- 0.74 kg of BW and 23 +/- 3 d of age) were randomly allotted to 5 treatments on the basis of BW, each treatment composed of 4 pens, each pen having 14 pigs. Dietary treatments included positive control (PC; basal diet + 150 mg/kg apramycin and 10 mg/ kg colistin sulfate); and potato protein (PP), consisting of the basal diet with 0, 0.25, 0.50, or 0.75% of potato protein. Diets were fed in 2 phases: phase I (d 0 to 14 postweaning) and phase 2 (d 14 to 28 postweaning). Potato protein was extracted from a value-added type of the new potato variety, Solanum tuberosum L. cv. Gogu valley, and was shown to have a minimum inhibitory concentration of 300 to 500 mug/mL. Performance of PC was compared with 0.25 to 0.75% PP, whereas linear and quadratic trends of increasing PP (0 to 0.75% PP) were tested. Over the 28-d trial, pigs fed the PC diets showed improved overall ADG (P < 0.05) and G:F (P = 0.090) compared with pigs fed PP, whereas increasing levels of PP linearly improved ADG (P < 0.05), ADFI (P = 0.052), and G:F (P = 0.098). The digestibility of DM and CP in both the phases was greater in PC than PP, and feeding of PP linearly improved the DM digestibility (P < 0.05) in phase II. The bacterial populations in the feces of pigs fed PC and PP were comparable, except for total bacteria and coliform bacteria in the feces at d 14 and 28, which were decreased in PC; and feeding of PP was effective in linearly reducing the populations of microbes in feces and contents of cecum, colon, and rectum. There was linear increase (P < 0.10) in skin-fold thickness in response to phytohemagglutinin with an increase in PP levels. Haemagglutinin titers on d 21 were greater (P = 0.054) in PC, and at d 28 the haemagglutinin titers were quadratically affected in pigs fed PP (P = 0.070). There was a trend toward a decrease in crypt depth (P = 0.068) and a greater villus height:crypt depth ratio (P = 0.082) of ileum in PC compared with PP. These results suggest that PP may be an alternative to medicated feed with antibiotics because it showed antimicrobial activity by effectively reducing the population of coliform bacteria and also improved the performance of weanling pigs.