Two trials were conducted to evaluate effects of grain adaptation protocol on subacute acidosis, feeding behaviour and ADG of cattle. In trial one, 12 crossbred heifers (384 ¡À 25 kg) were stepped from 40% to 90% dietary concentrate by either rapid adaptation (RA; one step-up diet fed for 3 d) or by gradual adaptation (GA; five step-up diets fed for 3 d each). Mean daily ruminal pH variables did not differ (P > 0.10) between treatments but variances of a number of ruminal pH variables were greater (P < 0.05) for RA than GA during adaptation to 65% and 90% concentrate. Mean hourly pH did not differ over the first 24 h of adaptation to 65% concentrate, but variance of hourly pH tended (P < 0.10) to be greater for RA than GA for eight of the first 24 h of adaptation to 90% concentrate. Increased variance in ruminal pH parameters was associated with detection of acidosis in certain individuals. On d 1 of 90% concentrate, ruminal pH tended (P = 0.07) to be lower at 11 and 12 h post-feeding with RA than with GA. Ruminal volatile fatty acids (VFA) and osmolality were similar between treatments. In trial two, 120 crossbred heifers (366 ¡À 23 kg) were adapted from 40% to 90% concentrate. A protocol identical to trial one was used with the addition of moderate adaptation (MA; three step-up diets fed for 3 d each). The increase to 65% concentrate caused reduced daily bunk attendance and increased maximum intermeal interval for RA compared to MA and GA cattle but the increase to 90% did not. ADG was reduced for RA compared to MA or GA during adaptation but over day 1 to 69 ADG did not differ between treatments (P ¡Ý 0.41). Current management strategies for preventing acidosis in pens of cattle are based on responses of the most susceptible individuals. Improved understanding of individual responses to acidotic challenge may allow development of more effective acidosis prevention practices.

Dietary supplements were provided during 24 hour transport from hatchery and growth of turkeys in two trials. Female poults (768 and 825 respectively) were used in two 3 x 4 factorial analyses (transportation supplement x post placement supplement) with treatment provided during transport (no supplement, Oasis® and Oasis® + lysozyme (0.01%)) and as dietary supplements post-placement (no supplement, Bacitracin Methylene Disalicylate (BMD)(ANTI), lysozyme (LYS), BMD + lysozyme (AL)) as the main effects. Growth, incidence of mortality, gastrointestinal size, strength and histology and behavioural data was collected. Transport supplementation of poults did not improve growth or reduce mortality, but influenced early feeding and drinking behaviour at placement. Body weight and feed consumption increased and percent mortality decreased for birds fed AL. Gizzard and proventriculus weight increased when birds consumed ANTI and jejunal breaking strength was highest for birds consuming LYS. Villi morphology and bird behaviour were not affected by dietary supplementation.

Studies were conducted to investigate the interactive effects of exogenous enzymes andorganic acids on in vitro and in vivo nutrient digestion and growth performance of broiler chicks.In Study 1, five exogenous enzyme products including ??-glucanase, xylanase, amylase, ??-galactosidase and protease, were assayed in triplicate at their optimum pH levels and at pH levelsof 3.0, 6.0, 6.5, 7.0 and 7.5, which were used to simulate pH levels found in the gizzard, the diet,the crop, and the proximal and distal parts of small intestine, respectively. The pH gradient wasobtained by dissolving the enzymes in different buffers. Results suggested that the pH levelscommonly found in the avian digestive tract were either too high or too low for maximumactivity of the exogenous enzymes, such as ??-galactosidase and protease.In Study 2, broiler chicks were fed corn basal, barley basal or wheat basal diets withdifferent levels or different sources of organic acids. Dietary inclusion of graded levels oforganic acids linearly reduced the pH of the diet and crop content, but not the pH of the digestasampled in the gizzard and small intestine. The inclusion of 2% organic acids (citric acid orfumaric acid) in broiler diets had either no effect or negative effects on chick growthperformance.In Study 3, an in vitro model was used to simulate the chicken's digestive process in thecrop, the gizzard and the small intestine. Soybean meal and raw whole soybeanwere used as substrates. Graded levels of either ??-galactosidase (0 to 13,792 units/kg) or protease(0 to 888 units/kg) and 0 or 2% citric acid were added to the substrates in a factorialarrangement. Reducing sugars, ??-amino nitrogen and trypsin inhibitor content were measured.The data indicated that increasing levels of ??-galactosidase linearly increased the release of thereducing sugars from the soybean meal. Addition of citric acid further increased the activity of ??-galactosidase, resulting in more reducing sugars were released. Increasing the supplementarylevels of protease linearly increased the ??-amino nitrogen release from the soybean meal and rawwhole soybean. Trypsin inhibitor content in the raw whole soybean was not influenced by theapplication of the protease.In Study 4, broilers were fed low energy or normal energy basal diets with ??-galactosidase,amylase and acidification of diet and water. Growth performance, AMEn and digestibility ofDM, CP and NDF were observed. Alpha-galactosidase improved the AMEn of the diets andincreased the weight gain and feed intake of broiler chicks. Citric acid decreased the crop pH andenhanced the activity of ??-galactosidase in the crop. Citric acid decreased the AMEn of the dietsand chick growth performance. These effects were corrected by supplementing ??-galactosidase.The activity of ??-galactosidase was enhanced by simultaneously using organic acid. Thenegative effects on chick growth performance by dietary inclusion of organic acids werecorrected by simultaneously using ??-galactosidase.

The role of vitamin K in the blood clotting cascade has been well documented. Vitamin K has recently been implicated in improving bone health. The current studies were conducted to determine the effects of vitamin K in diets with and without mycotoxin contaminated corn on growth performance, bone characteristics, and related blood metabolites in pigs from weaning to market. Menadione sodium bisulfite complex (MSBC, 33% vitamin K) was chosen as the source of supplemental vitamin K because it is the most common form fed to swine. Vitamin K was tested at 0, 0.5, and 2.0 ppm in a corn-soybean meal based diets on two generations of pigs to evaluate any time and dose responses. The first generation of pigs was subjected to mycotoxin contaminated corn in the nursery phase to test for any interactions between the toxins and vitamin K. The addition of 0.5 ppm vitamin K reduced (P < 0.0001) prothrombin time. No additional decrease in prothrombin time was detected when increasing vitamin K inclusion from 0.5 to 2.0 ppm. With regard to growth performance, daily gain, feed intake, and feed efficiency were unaffected (P > 0.10) by supplemental vitamin K. However, pigs fed mycotoxin contaminated corn ate less (P = 0.005) and grew slower (P = 0.015) compared to those receiving good corn. The addition of vitamin K did not alleviate the negative growth effects in response to corn type. Vitamin K did not affect bone characteristics (P > 0.10), blood Ca (P > 0.05) or OC (P > 0.10). Other than blood clotting it does not appear that dietary vitamin K provides any additional benefits at these levels of inclusion and stages of swine production.

This study monitored a cohort of youth rugby league players from one professional club in England, across three competitive seasons (under-15 to under-17 age group). The aims were to establish which dimensions of growth and performance characterized players who were either coach-selected or unselected each season and to evaluate annual developments in growth and performance. It was also necessary to establish the credibility of various measurement techniques that are implicated in the talent identification process. In the assessment of sprint performance, GPS measurements systematically underestimated both distance and timing gate speed but can be used to reliably evaluate sprint performance, particularly for measurements of peak speed (95% Limits of Agreement (LoA) = 0.00 ± 0.8 km·h-1; CV = 0.78%). Using a larger sample of youth team sport players (n = 60), multiple linear regression analysis, incorporating mean and peak GPS speeds as predictors of timing gate speed, yielded a prediction model that was able to provide a valid alternative to timing gates in the assessment of sprint performance over 30 m. With regards to the reliability of assessments of sport-specific skill in youth rugby league players, no comparisons met the pre-determined analytical goal of ‘perfect agreement’, meaning that up to 56% of players’ skill could be misinterpreted. The credibility of such assessments should be questioned and alternative tests considered. In the period between the under-15 and under-16 group, there were large annual increments in speed (5.02 Δ%), force (13.82 Δ%) and power (19.85 Δ%) generated over 10 m sprint intervals and predicted vertical jumping power (13.02 Δ%), with concomitant developments in body mass (5.14 Δ%), lean body mass (3.20 Δ%) and predicted muscle of the quadriceps (10.12 Δ%). A discriminant function analysis also highlighted 30 m force and 10 m acceleration as significant predictors of selected players in the under-15 group and under-16 group, explaining 47.3% and 40.7% of the between-group variance, respectively – which was the case independent of age at peak maturity. However, there were 5 no differences between selected and unselected players in the under-17 group. During match time, there were differences between selected (57.1 ± 11.9 min) and unselected (44.1 ± 12.3 min) players for average playing interval in the under-16 group. In turn, selected players covered more total distance (5181.0 ± 1063.5 m c.f. 3942.6 ± 1108.6 m, respectively; P = 0.012) and high intensity distance (1808.8 ± 369.3 m c.f. 1380.5 ± 367.7 m, respectively; P = 0.011) than unselected players. When age at peak height velocity (PHV) was statistically controlled, only distance in zone 3 and summated-HR remained higher in the selected players of the under-16 group. Conversely, higher values amongst the unselected under-16 players for total and relative distance in zone 4, 5 and high intensity were revealed. There was a relationship in the under-15 group (R = 0.702, P < 0.001), under-16 group (R = 0.607, P < 0.001) and under-17 group (R = 0.671, P < 0.006) between the number of successful ball carries and 10 m sprinting force, thus supporting the use of 10 m sprinting force as a predictor of match performance. The relationship (r = 0.51, P = 0.044) between aerobic capacity and HIT·min-1 in the under-17 group also provides preliminary evidence of aerobic endurance as a potential predictor of match running intensity. It was concluded that players who are coach-selected are not characterized by match related performance variables but are offered greater match exposure during the under-16 age group, resulting in larger running distances. Unselected players are unrewarded for higher intensity running during matches when maturational age is statistically controlled and are also equally effective in regard to tackling and ball carrying outcomes. These results collectively indicate the inability of match performance measurements to contribute to talent identification processes in players of this type. The changes in growth and performance should be used to guide talent development practices of rugby league coaches. In particular, the assessment of force (i.e. the product of acceleration and body mass) should be considered as an important factor in differentiating between higher and lower ability players, as well as relating to match performance.

Pharmacological levels of inorganic forms of copper (Cu) and zinc (Zn) are frequently used in diets for pigs to improve performance and control post-weaning colibacillosis. However, the use of such forms and levels causes mineral accumulation in the soil, and is a non-sustainable practice from an environmental perspective. Alternatively, organic complexes of copper (Cu) and zinc (Zn) have been proposed to be more available to pigs, and when included at lower levels than inorganic sources of these minerals have significantly reduced mineral excretion in faeces without compromising performance. However the effect of these organic minerals fed simultaneously at low levels of inclusion has not been well studied. The general hypothesis tested in this thesis was that concentrations of Cu and Zn in faecal material would be reduced when fed in an organic (Bioplex®) form without compromising performance or mineral homeostasis in growing/finishing pigs, in comparison to Cu and Zn fed in an inorganic (sulphate) form. Two experiments were performed to test this hypothesis: Experiment 1 was designed as a 2x2 factorial arrangement of treatments, with two mineral forms (Bioplex® and Sulphate) and two inclusion levels (High and Low). The “low” levels aimed at providing 80 mg/kg of dietary Cu and Zn, and the “high” levels aimed at providing 160 mg/kg of dietary Cu and Zn. Experiment 2 was designed as a 3x2 factorial arrangement of treatments, with two mineral forms (Bioplex® and Sulphate) and three inclusion levels (Low, Medium and High). The “low” levels aimed at providing 25 mg/kg of Cu and 40 mg/kg of Zn, the “medium” levels aimed at providing 80 mg/kg of both Cu and Zn, and the “high” levels aimed at providing 160 mg/kg of both Cu and Zn in the diet. Unfortunately the Medium sulphate grower diet was contaminated with excess Zn while manufacturing, which led to the exclusion of this treatment from the study. In Experiment 1, pigs fed LB (Low Bioplex®) or HS (High Sulphate) diets grew faster (P=0.014) and their carcasses were 3.5 kg heavier (P=0.020) than LS (Low Sulphate)- or HB (High Bioplex®)-fed pigs. Pigs fed LB or HS diets had lower (P=0.001) levels of Zn in plasma, a higher (P=0.029) concentration of Zn in the pancreas and a lower (P=0.020) concentration of Zn in bone than pigs fed LS or HB diets. The concentration of Cu in liver increased (P=0.017) with the concentration in the diet as did Cu and Zn levels in faeces (P<0.001) without any difference between mineral forms. Feed conversion ratio (FCR) tended to be improved (P=0.062) by the inclusion of Bioplex® in the diet. The inclusion of Bioplex® reduced (P=0.003) subcutaneous fat depth at the P2 site by 2.2 mm compared to the sulphate. In Experiment 2, there was no difference (P>0.05) in growth rate between experimental diets, but again there was an overall improvement (P=0.012) in FCR when Bioplex® were included. Blood and tissue Cu and Zn concentrations were within normal physiological ranges in all treatments, supporting a reduction of Cu and Zn levels in the diet. Only Zn level in plasma during the growing phase and Cu and Zn concentration in tissues increased (P<0.001) with the addition in the diet. None of the biomarkers of Cu or Zn status analysed in the pigs showed any difference between the inorganic and the Bioplex® forms. Copper and Zn concentrations in faecal material decreased (P<0.001) with their inclusion in the diet, and only in the finishing collection there was a further decrease of 10% in Zn faecal concentration when Bioplex® was included instead of the sulphate at similar low levels. Carcass and meat quality measures were independent of the Cu and Zn form or level, however a higher proportion of carcasses from LB-fed pigs had <14 mm subcutaneous fat depth at the P2 site. The inclusion of Bioplex® failed to have a significant effect on Cu excretion and its inclusion had an inconsistent effect on Zn excretion. The overall findings from this thesis partially supported the hypothesis that the inclusion of Bioplex® would reduce the concentration of Cu and Zn in faeces compared to the inclusion of inorganic forms at similar inclusion levels. Nevertheless, total Cu and Zn levels in growing/finishing pig diets could be reduced from 160 mg/kg of both Cu and Zn to 30 mg/kg Cu and 60 mg/kg Zn, in either the sulphate or the Bioplex® form, without negatively affecting performance or mineral homeostasis in the pigs and significantly reducing Cu and Zn excretion (between 50 and 80%). The advantage of including Bioplex® instead of sulphates was in the improvement in FCR. Carcass and meat quality were independent of the form and level of dietary Cu and Zn.

Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-11Bitstream added on 2014-06-13T19:57:44Z : No. of bitstreams: 1 barros_tfm_me_botfmvz.pdf: 355685 bytes, checksum: d0bdb5b474f7d736413cb296b0689549 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O objetivo foi avaliar o efeito do enriquecimento da gaiola sobre o comportamento e desempenho de coelhos em crescimento, com diferentes formações de grupos sociais. O experimento, conduzido em duas etapas, teve inicio na desmama, com cinco semanas, e finalizou com 11 semanas de idade. Em cada etapa foram utilizados 72 coelhos do grupo genético Botucatu, 36 machos e 36 fêmeas, alojados em 12 gaiolas de arame galvanizado, seis animais por gaiola. Os animais foram distribuídos em um delineamento inteiramente casualizado, com arranjo fatorial de 2 x 3 (com e sem enriquecimento e em três tipos de grupos sociais – fêmeas, machos e misto), totalizando 6 tratamentos com 2 repetições em cada etapa. Dois pedaços de eucalipto (15 x 3 x 3 cm), usados como enriquecimento, foram dependurados com arame no teto da gaiola e posicionados entre 20 e 30 cm do piso. Seis câmeras foram usadas para registrar imagens do comportamento dos animais por 24h contínuas, uma vez por semana, na 7ª, 10ª e 11ª semanas. Quatro pontos de luz negra foram acionados no período noturno. Foram efetuados registros pontuais dos comportamentos: lúdico, exploratório, agressivo, estereotipado, interação com o enriquecimento, interação social e cecotrofia. Para avaliação do bem-estar foram utilizadas as frequências dos comportamentos lúdico e estereotipado, além da interação com o enriquecimento. Aos 77 dias foi registrado o número de lesões cutâneas nas orelhas e em outras partes do corpo, que pudessem ter sido ocasionadas por brigas. Em seguida, os animais foram abatidos e o peso dos órgãos, incluindo o cérebro, da carcaça e de seus cortes foram coletados. Não houve diferença no desempenho entre os tratamentos. O efeito da interação enriquecimento x grupo social revelou que os machos com enriquecimento... / The objective was to evaluate the effect of cage enrichment on the behavior and welfare of growing rabbits in different social groups. The experiment, carried out in two phases, was initiated at weaning with five weeks of age and ended at 11 weeks of age. Seventy-two rabbits from the Botucatu genetic group, 36 males and 36 females, were housed in 12 wire cages, six per cage, in each phase. The animals were assigned to a completely randomized design with a 2 x 3 factorial arrangement (with or without enrichment and in three types of social groups – females, males, and mixed) comprising six treatments with two replicates in each phase. Two eucalyptus sticks (15 x 3 x 3 cm) were hung from the cage ceiling with wires to be positioned at 20 to 30 cm from the cage floor. Six cameras were used to record the animals’ behavior continuously for 24 hours, once a week on weeks 7, 10 and 11. Four black light bulbs were turned on during the night. The following behavior activities were scored as they occurred: ludic, exploratory, agressive, stereotypes, interaction with the enrichment, social interaction, and cecotrophy. The frequencies of ludic and stereotyped activities were used to evaluate welfare in addition to interaction with the enrichment. At 77 days of age the number of skin lesions in the ears and other parts of the body, that could have been caused by fights among animals, were recorded and the animals were slaughtered. The weight of organs, including the brain, carcass and carcass parts were registered. No difference in growth performance was detected among treatments. An enrichment x social group interaction effect... (Complete abstract click electronic access below)

The effects of diet type, amino acid (AA), and apparent metabolizable energy (AME) levels in male broiler diets from d 8 to 21 on blood, small intestine, bone, and growth performance were investigated. Eight experimental diets with 2 protein sources [high inclusion of distiller's dried grains with solubles diet (hDDGS) or high inclusion of meat and bone meal diet (hMBM)], 2 AA densities (moderate or high), and 2 AME densities (2,998kcal/kg or 3,100kcal/kg), were fed to the broiler chicks from 8 to 21 days of age (d). High AME diets may lower feed cost by lowering feed intake. Intestinal morphology changes responded to dietary treatments, which may facilitate nutrients digestion and absorption in high MBM diets as well as in high DDGS diets. In addition, high AA or AME diets from 8 to 20 d improved feed conversion during experimental phase and influenced meat yields at 55 d.

The objective of this research was to use Bacillus subtilis-based probiotics alone or combined with various additional antibiotic alternatives (yeast-derived prebiotics and zinc supplementation) to maintain gut health and improve growth performance of antibioticree broilers. Three consecutive studies have been conducted to evaluate dietary effects on intestinal morphology, digestive organ development, microbiota, and growth performance of commercial broilers under different coccidia-challenge circumstances. In the first study, broilers were raised under commercial conditions, without coccidia-challenge (Chapter III). Broilers fed diets supplemented with antibiotics exhibited the highest body weight gain (BWG) from d 15 to 27. Broilers fed diets supplemented with B. subtilis or prebiotics + B. subtilis exhibited higher BWG from d 28 to 41 and higher BWG from d 0 to 41 as compared to birds fed control diets. In the second study, broilers were exposed to a clinical coccidia-challenge (Chapters IV and V). Interaction and main effects of the dietary supplement and coccidial vaccination were studied. Diets supplemented with Prebiotics + B. subtilis facilitated broilers to reach a similar feed conversion ratio (FCR) as to the antibiotic control group from d 0 to 56. Feeding diets supplemented with B. subtilis to coccidial vaccinated broilers reduced microbiota diversity by increasing the proportion of an antibiotic-resistant bacterium, Rikenella microfusus. In the third study, interaction and main effects of the subclinical coccidia-challenge and the dietary supplement were studied (Chapters VI and VII). The dietary anticoccidial supplementation increased feed intake and BWG and decreased FCR of broilers from d 15 to 28. However, dietary B. subtilis supplementation did not improve any growth performance of broilers. The combined use of zinc and B. subtilis lowered the high mortality of broilers fed diet supplemented with B. subtilis or zinc alone. Additionally, the dietary supplementation of zinc lowered the proportion of Clostridium in cecal contents of broilers. In conclusion, different nutrition strategies should be considered when broiler chickens are under different health circumstances. Bacillus subtilis-based probiotics have potential to replace the antibiotics, but not anticoccidial feed additives.

The effects of supplementation of riboflavin along with Bacillus subtilis was investigated on growth performance and intestinal health of broilers under coccidial challenge. Treatments are 3 × 2 × 2 factorial arrangement, which includes 3 levels of riboflavin (0.75, 6.6 (recommended), and 20 ppm), with or without Bacillus subtilis, and with or without coccidial challenge. Coccidial challenge impaired the intestinal morphology and reduced body weight (BW), body weight gain (BWG), and feed intake and increased FCR between d 14-28. However, the cocci impact on birds was reduced along with age, as the effects on internal organs was reduced, which allowed birds to recover. However, coccidiosis reduced overall BW and BWG and increased abdominal fat pad weight and slight woody breast incidence. In conclusion, riboflavin at tested level was unable to enhance growth performance and intestinal health, but its inclusion altered birds response to coccidial challege other than feeding Bacillus subtlis alone.