Finish Phase Research Articles

31 Effects of dietary standardized ileal digestible (SID) lysine (Lys) levels and dietary SID tryptophan to Lys ratios on growth performance and behavior of late-nursery to finish maternal barrows

Abstract The objective was to determine the effects of dietary standardized ileal digestible (SID) lysine (Lys) levels and SID tryptophan (Trp) to Lys ratios on growth performance and behavior of late-nursery to finish maternal barrows. A total of 2,293 barrows (PIC Camborough, initially 11.9 ± 0.35 kg) were used in this trial with 96 mixed-sex pens and 23 to 25 pigs/pen. There was a total of 6 dietary phases: P1:11.9-29.5 kg; P2:29.5-49.6 kg; P3:49.6-62.6 kg; P4:62.6-80.3 kg; P5:80.3-103.3 kg; and P6:103.3-137.8 kg. Pens were blocked by body weight and randomly allotted to 1 of 6 treatments:T1: 100% Lys (dietary SID Lys levels meet PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T2: 100% Lys and 18.5% of SID Trp:Lys ratio; T3: 100% Lys and 16.0% of SID Trp:Lys ratio; T4: 80% Lys (dietary SID Lys levels meet 80% of PIC SID Lys recommendation) and 21.0% of SID Trp:Lys ratio; T5: 80% Lys and 18.5% of SID Trp:Lys ratio; and T6: 80% Lys and 16.0% of SID Trp:Lys ratio for P1-P2 and then 100% Lys and 18.5% of SID Trp:Lys ratio for P3-P6. Ear lesion (EL) was monitored during P2-P5. Data were analyzed using a linear mixed model in R Studio (Version 3.5.2, R Core Team; Vienna, Austria). Pigs fed T1 and T2 showed improved average daily gain than T6 (P < 0.05), with other treatments intermediate (Table 1). Pigs fed T2 showed improved average daily feed intake as compared with T6 (P < 0.05), with other treatments intermediate. There was no evidence for significant difference on feed-to-gain ratio or mortality. Removal was significantly greater for pigs fed T6 compared with all other treatments (P < 0.05). Pigs fed T2 had significantly greater hot carcass weight than T4, with other treatments intermediate. There was no evidence for significant differences on carcass yield or lean percentage. Pig fed T6 had significantly greater incidence of EL in P2 than all other treatments (P < 0.05). Pigs fed T4 and T6 had greater incidence of EL in P3 than T1 (P < 0.05), with other treatments intermediate. Pigs fed T5 and T6 had significantly greater incidence of EL in P4 than T1, T2, and T3 (P < 0.05), with T4 intermediate. During P5, pigs fed T4 and T5 had the greatest incidence of EL (P < 0.05), while pigs fed T6 had significant greater incidence of EL than T3 (P < 0.05), with T1 and T2 intermediate. In conclusion, dietary SID Lys and SID Trp:Lys ratio less than PIC recommendation during late-nursery-to-grower phase resulted in compromised overall growth performance of maternal barrows, even with restored dietary SID Lys and SID Trp:Lys levels in finish phase. Dietary SID Lys level and/or SID Trp:Lys ratios lower than PIC recommendation may result in greater incidence of aggression behavior in maternal barrows.

To flat or not to flat? Exploring the impact of flat-side design on rotary instruments using a comprehensive multimethod investigation.

To assess the influence of a flat-side design on the geometry, metallurgy, mechanical performance and shaping ability of a novel nickel-titanium rotary instrument. Sixty-five new 25-mm flat-side rotary instruments (size 25, taper 0.04) and their nonflat-side prototypes (n = 65) were assessed for major deformations and examined regarding macroscopic and microscopic design, determination of nickel and titanium elements ratio, measurement of phase transformation temperature and evaluation of mechanical performance parameters including time/cycles to fracture, maximum torque, angle of rotation, maximum bending and buckling strengths and cutting ability. Additionally, unprepared canal areas, volume of hard tissue debris and percentage reduction of dentine thickness were calculated for each tested instrument after preparing mesial canals of mandibular molars (n = 12), using micro-CT imaging. Statistical analyses were performed using the U-Mann-Whitney test and independent Student t-test (α = 5%). The number of spirals (n = 8) and blade direction (clockwise) were similar between both flat and nonflat instruments, whilst the helical angles were equivalent (⁓25°). Flat-instruments showed inconsistencies in the homogeneity of the gold colour on the flat-side surface, blade discontinuity, and incomplete and variable S-shaped cross-sections. The titanium-to-nickel ratios were equivalent, but significant differences in the R-phase finish and austenitic start phase transformation temperatures were observed between the flat and nonflat-side instruments. The flat-side instruments demonstrated superior cutting ability compared to the nonflat instruments, as well as, significantly lower values for time to fracture, rotation to fracture and maximum torque to fracture (p < .001). No statistical difference was observed between tested instruments regarding angle of rotation (p = .437), maximum bending (p = .152) and buckling load (p = .411). Preparation protocols using flat and nonflat instruments did not show any statistically significant differences (p > .05). All flat-side instruments exhibited deformation after shaping procedures. The flat-side instrument showcased enhanced cutting ability compared to its nonflat counterpart. However, it exhibited inferior performance in terms of time, rotation and maximum torque to fracture, along with distinct phase transformation temperatures. No differences were observed in the titanium-to-nickel ratios, angle of rotation, maximum bending, buckling load, preparation time, percentage of untouched canal walls, volume of hard tissue debris and percentage reduction of dentine thickness.

Comparison of geometric design, metallurgical features and mechanical behavior of ProTaper Gold SX and two replica-like instruments

Objectives: To assess the characteristics, performance, and safety of ProTaper Gold SX (PTG SX) replica-like instruments. Methods: A multimethod research involving the assessment of geometric design (macro and through scanning electron microscope), Ti/Ni proportions (energy-dispersive X-ray spectroscopy), phase transformation temperatures (differential scanning calorimetry), torsional resistance, and flexibility was conducted to compare two SX replica-like instruments (Premium Taper Gold and Go-Taper Flex) with the original PTG SX. Results were compared using one-way ANOVA with post hoc Tukey or Kruskal-Wallis tests according to gaussian or non-gaussian distribution (Shapiro-Wilk test). The significance level was set at 0.05. Results: The three SX instruments have nine cutting blades with helix angles of approximately 21º, symmetrical blade geometry without radial lands, a convex triangular cross-section design, and near equiatomic Ti/Ni atomic proportions. Design differences were observed at the tip geometry and surface finishing, which was smoother in the Premium Taper Gold and irregular in the Go-Taper Flex. Distinct R-phase start (Rs) and finish (Rf) phase transformation temperatures were noted between PTG (Rs ~48ºC and Rf ~30ºC), Go-Taper Flex (Rs ~43ºC and Rf ~25ºC), and Premium Taper Gold (Rs ~30ºC and Rf ~15ºC). In the mechanical tests, Go-Taper Flex presented lower maximum torque (mean 0.5 N.cm) and higher bending resistance (mean 582.2 gf) (less flexibility) than PTG (means 0.8 N.cm and 447.1 gf) (P&lt;0.05). No significant differences were observed in the mechanical tests between Premium Taper Gold and PTG (P&gt;0.05). Conclusions: Overall, the tested replica-like systems showed different features compared to the original PTG SX instrument.

PSXI-8 Corn stover feedlot diets with elevated mycotoxins and binder effect on cattle performance

Abstract Weather conditions often dictate the quality of corn, corn silage, and corn stover harvested for livestock feed. When growing and/or harvest conditions are wet, mycotoxin producing fungi can flourish. Mycotoxin levels were determined to be elevated in the fall 2018 corn crop (Table 1). A 3 x 2 factorial experiment was initiated to observe effects of a mycotoxin binder, hydrated sodium calcium aluminosilicate (Engage-M, United Animal Health, Sheridan, IN), on cattle performance. Three treatment diets with elevated mycotoxin levels were amended with Engage-M fed at 0 or 14 g hd-1 d-1. Steers (n = 72, 12 pens total) were fed during Grow (21 d) and Finish (51 d) phases. During the Grow phase a 52% corn silage, 20% DDGS, and 8% supplement basal diet was fed and treatments were an additional 20% diet DM included as corn silage (CSIL), conventional corn stover (CST), or single-pass bale stover (SPB). Cattle fed Engage-M during Grow phase had numerically higher daily gains, 1.35 kg d-1, compared to no binder, 1.26 kg d-1 (P = 0.17). During the Finish phase, all cattle were fed similarly (72.1% rolled corn, 12% corn silage, 8.9% DDGS, 7% supplement diet DM). Cattle fed Engage-M tended (P = 0.09) to have increased daily gains, 2.07 kg d-1, compared to no binder, 1.9 kg d-1. Dry matter intake was similar for both treatments during the Finish trial, 12.9 kg hd-1 d-1 (P = 0.83), suggesting the increase in cattle performance was due to improved utilization of feed and not feed intake. The Finish phase feed to gain ratio was 6.25 vs. 6.83 (P = 0.06) with and without Engage-M, respectively. The trend was for cattle fed Engage-M to be 9.2% more efficient. The present study suggests that feeding Engage-M may increase cattle performance when diets have elevated levels of zearalenone and vomitoxin.

PSIX-15 Intake of corn stover plant parts by feedlot beef steers

Abstract Corn stover supports feedlot operations in intensive corn producing regions. A single-pass corn grain and stover harvest system was developed to increase efficiency of field operations and capture different anatomical fractions than are typically harvested with conventional corn stover. The objectives were to feed beef steers diets that included a roughage component consisting of harvested corn residue in chopped form from conventional corn stover bales (CST) or single-pass bales (SPB). Whole-plant corn silage (WPCS) served as a control. Steers (n = 90, 5 pens/treatment) were fed during Grow (84 d) and Finish (66 d) phases to assess consumption of corn plant botanical fractions and calculate net energy values of the stover feeds. Cattle consumed a larger proportion of stover as cob (P &amp;lt; 0.001) and less as stalk (P = 0.001) when stover was offered as SPB rather than CST. These differences are consistent with the fractional distribution of botanical components offered. During the Grow phase, cattle fed WPCS had greater (P = 0.018) daily gains (1.27 kg d-1) than cattle fed the SPB (1.14 kg d-1) and CST (1.08 kg d-1), and were more efficient than CST cattle. Steers sorted corn stover during both phases and consumed 52.5% of corn stover offered. SPB cob intake was 70% greater than CST cob intake (P &amp;lt; 0.01) indicating if more cob fraction is available, cattle will consume more. There was no treatment effect on final body weight (P = 0.37) or growth rate (P = 0.12) during the Finish phase. Stover NEm and NEg were calculated using Dairy NRC (2001) methods for SPB (1.04 and 0.49 Mcal kg-1) and CST (0.98 and 0.44 Mcal kg-1), respectively. In conclusion, there is evidence that CST and SPB can substitute for WPCS in beef feedlot diets without adverse effects on overall steer performance.

Effects of dietary enrichment with a marine oil-based n-3 LCPUFA supplement in sows with predicted birth weight phenotypes on growth performance and carcass quality of offspring

Effects of a marine oil-based n-3 LCPUFA supplement (mLCPUFA) fed from weaning until the end of the next lactation to sows with a predicted low litter birth weight (LBW) phenotype on growth performance and carcass quality of litters born to these sows were studied, based on the hypothesis that LBW litters would benefit most from mLCPUFA supplementation. Sows were allocated to be fed either standard corn/soybean meal-based gestation and lactation diets (CON), or the same diets enriched with 0.5% of the mLCPUFA supplement at the expense of corn. The growth performance from birth until slaughter of the litters with the lowest average birth weight in each treatment (n=24 per treatment) is reported in this paper. At weaning, each litter was split between two nursery pens with three to six pigs per pen. At the end of the 5-week nursery period, two barrows and two gilts from each litter that had individual birth weights closest to their litter average birth weight, were moved to experimental grow–finish pens (barn A), where they were housed as two pigs per pen, sorted by sex within litter. Remaining pigs in each litter were moved to another grow–finish barn (barn B) and kept in mixed-sex pens of up to 10 littermates. After 8 weeks, one of the two pigs in each pen in barn A was relocated to the pens holding their respective littermates in barn B. The remaining barrows and gilts were individually housed in the pens in barn A until slaughter. Maternal mLCPUFA supplementation increased docosahexaenoic acid (DHA) concentration in the brain, liver and Semitendinosus muscle of stillborn pigs (P<0.01), did not affect eicosapentaenoic acid and DHA concentrations in sow serum at the end of lactation, and did not affect average daily gain, average daily feed intake or feed utilization efficiency of the offspring. BW was higher (P<0.01) in the second half of the grow–finish phase in pigs from mLCPUFA sows compared with controls in barn A, where space and competition for feed was minimal, but not barn B. Carcass quality was not affected by treatment for pigs from barn A, but maternal mLCPUFA supplementation negatively affected carcass quality in pigs from barn B. Collectively, these results suggest that nutritional supplementation of sows can have lasting effects on litter development, but that feeding mLCPUFA to sows during gestation and lactation was not effective in improving growth rates or carcass quality of LBW litters.

Effect of Finish Line on Marginal Fit of Sintered Gold Copings

The aim of this study was to evaluate the vertical marginal gap of sintered gold copings and metal-ceramic crowns with different finish line preparations: a beveled round shoulder (BRS) and a beveled long chamfer (BLC), testing the null hypotheses that there are no differences in marginal gap regardless of finish line and phase of restoration (coping or crown). Stainless steel master models were fabricated to simulate tooth preparation for metal-ceramic crowns with different finish lines (BRS and BLC). Ten dies were obtained from each model. Preparations were coated with 2 layers of spacer to 1 mm from the margin. Sintercast gold copings were prepared, sintered and adjusted to the dies. The copings (n=10) were placed onto the master model and the marginal gap was measured in 24 equidistant points using optical microscopy (X230). An opaque and two body ceramic layers were subsequently applied to the copings and the same measuring procedure was performed for the crowns. The data were analyzed statistically using paired and unpaired Student's t-test (α=0.05). Mean marginal gap values (µm) for the copings and crowns were, respectively: 113.6 and 117.1 for the BRS; and 58.2 and 74.3 for the BLC preparation. Significantly greater marginal gaps (p=0.0307) were found for restorations with BRS than with BLC finish line, which also showed statistically significant differences in the gap size between coping and crown (p=0.001). In conclusion, marginal gap is influenced by ceramic application on copings fabricated on BLC preparation, and greater marginal gaps were found for restorations with BRS finish line, rejecting the experimental null hypotheses.

Consequences of a low litter birth weight phenotype for postnatal lean growth performance and neonatal testicular morphology in the pig

The consequences of a low litter average birth weight phenotype for postnatal growth performance and carcass quality of all progeny, and testicular development in male offspring, were investigated. Using data from 25 sows with one, and 223 sows with two consecutive farrowing events, individual birth weight (BW) was measured and each litter between 9 and 16 total pigs born was classified as low (LBW), medium (MBW) or high (HBW) birth weight: low and high BW being defined as >1 standard deviation below or above, respectively, the population mean for each litter size. Litter average BW was repeatable within sows. At castration, testicular tissue was collected from 40 male pigs in LBW and HBW litters with individual BW close to their litter average BW and used for histomorphometric analysis. LBW piglets had a lower absolute number of germ cells, Sertoli cells and Leydig cells in their testes and a higher brain : testis weight ratio than HBW piglets. Overall, LBW litters had lower placental weight and higher brain : liver, brain : intestine and brain : Semitendinosus muscle weight ratios than MBW and HBW litters. In the nursery and grow–finish (GF) phase, pigs were kept in pens by BW classification (9 HBW, 17 MBW and 10 LBW pens) with 13 males and 13 females per pen. Average daily gain tended to be lower in LBW than HBW litters in lactation (P = 0.06) and throughout the nursery and GF phases (P < 0.01), resulting in an increasing difference in body weight between LBW, MBW and HBW litters (P < 0.05). Average daily feed intake was lower (P < 0.001) in LBW than HBW litters in the nursery and GF phases. Feed utilization efficiency (feed/gain) was similar for LBW and HBW litters in the nursery, but was lower (P < 0.001) in HBW than LBW litters in the GF phase. By design, slaughter weight was similar between BW classifications; however, LBW litters needed 9 more days to reach the same slaughter weight than HBW litters (P < 0.001). BW classification did not affect carcass composition traits. In conclusion, LBW litters showed benchmarks of intrauterine growth retardation, LBW had a negative impact on testicular development and germ and somatic cell populations, and was associated with decreased postnatal growth during all phases of production; however, no measurable effect on carcass composition traits was established.

Magnetic Resonance Imaging Diagnosis of Rib Fracture in a Competitive Collegiate Rower: A Case Report.

Competitive collegiate rowing has a long history, dating back to the nineteenth century. The oldest American intercollegiate athletic event on record is the Yale-Harvard boat race in 18521. While the mechanics of the sport remain largely unchanged, the extent of training and level of competition for collegiate rowers continue to increase. Competitive rowing is no longer a seasonal sport; these athletes are involved in year-round training, on ergometers (rowing machines) and in the water. This level of training, combined with the specific repetitive movements involved in rowing, makes elite rowers especially susceptible to injury. The mechanics of the rowing motion can be analyzed in four phases: catch, drive, finish, and recovery. The catch phase is when the rower’s legs and back are fully flexed and the arms are extended as the oars enter the water. The drive phase is when the legs extend and the back slightly extends, followed by flexing of the arms to accelerate the oar through the water. The finish or release phase consists of the elbows drawing the blade through the water as well as movement of the handle down to remove the oar from the water. The recovery phase is when the oar is brought back to the starting position. The timing and magnitude of these motions can lead to strain and overuse injuries2. It is therefore not surprising that back injuries are very common among rowers. The differential diagnosis for back pain in a rower includes muscle strain, ligament and/or tendon injury, tear of the anulus fibrosus, or stress fractures. Although stress fractures of the ribs are rare in the general population, they have a relatively high frequency (6.1% to 22.6%) in competitive rowers3,4. While stress fractures have been long identified as a consequence of vigorous …

Effects of Plyometric Training on Ankle Joint Motion and Jump Performance

The purpose of this study was to quantify the effect of plyometric training (PT) in changes of jump abilities and ankle joint motions on repeated-rebound-jumps exercise without buffer function of lower limb joints. Seven female collegiate runners executed 10-repeated rebound jumps training (10 RJ) on a switch mat with maximum effort. Each subject executed the training program twice a week for 5 consecutive weeks. Parameters of repeated-rebound jumps training involved jump height (m), the contact time (s), flight time (s), and rebound jumps index (=RJ-index). Three-dimensional ankle joint kinematics of each subject were captured using ten motion capture systems (250 Hz). As a result, RJ-index, jump height, and flight time were increased significantly between pre-and post-test (p 0.001). But, the contact time decreased significantly. The relationships between rebound jumps index and jump height and between rebound jumps index and the durations of contact phase were highly correlated (r=0.858, r= 0.739; p 0.001). In addition, the time (%) between start and finish phase in the dorsiflexion angle of ankle joint was reduced significantly between pre-and post-test (p 0.001). The repeated-rebound-jumps exercise was shown to have an effect on improvement in stretch-shortening cycle (SSC) performance of lower limb joints in distance runners. The RJ-index and the time between start and finish phase in the dorsiflexion angle of ankle joint was shown to be a valid evaluation index of SSC performance. Therefore, repeated-rebound-jumps exercise is a significant training protocol where ankle behavior improves and where the performance of stretch-shortening cycle is enhanced.

Avaliação de milhos de diferentes densidades para frangos de corte

O trabalho foi realizado com o objetivo de determinar os valores nutricionais de milhos de quatro qualidades, obtidos por meio de estratificação em mesa densimétrica, para frangos de corte em diferentes idades. Os milhos foram designados como: MDA - milho de densidade alta; MDI - milho de densidade intermediária; MDB - milho de densidade baixa; e MDO milho de densidade original, composto de 25% de MDA, 50% de MDI e 25% de MDB. Três ensaios biológicos foram conduzidos utilizando-se o método tradicional de coleta total de excretas para determinação da energia metabolizável aparente corrigida (EMAn). O primeiro ensaio metabólico foi conduzido com pintos Cobb de 14 a 17 dias, o segundo, com pintos de 25 a 28 dias e o terceiro de 38 a 41 dias de idade. Foram realizadas análises químicas para determinação do perfil nutricional, classificação de grãos segundo a densidade e comparação por meio das estimativas de equações de predição do valor energético. Os valores da EMAn dos milhos de diferentes qualidades (MDA, MDI, MDB e MDO) determinados com frangos na fase inicial foram: 3562, 3382, 3198 e 3357 kcal/kg, para a fase de crescimento: 3576, 3555, 3229 e 3416 kcal/kg e, para a fase final 3610, 3554, 3354 e 3585 kcal/kg, respectivamente. Esses valores comprovam as significativas perdas energéticas dos milhos de mais baixa qualidade e a eficiência da mesa densimétrica em estratificar os grãos. A diferença da EMAn entre as idades das aves sugere melhor eficiência de utilização da energia com o avanço da idade. As equações de predição podem ser utilizadas para estimar o valor energético de milhos, tanto por sua classificação como pelas análises bromatológicas. Entretanto, o erro sistemático associado a cada equação de predição pode comprometer a exatidão de seu valor nutricional.

Expert rowers’ motion analysis for synthesis and technique digitalization

Four expert rowers’ gestures were gathered on the SPRINT rowing platform with the aid of an optic motion tracking system. Data were analyzed in order to get a digital representation of the features involved in rowing. Moreover, these data provide a dataset for developing digital models for rowing motion synthesis. Rowers were modeled as kinematic chains, data were processed in order to get position and orientation of upper body limbs. This representation was combined with SPRINT data in order to evaluate features found in the literature, to find new ones and to build models for the generation of rowing motion. The analysis shows the effectiveness of the motion reconstruction and two examples of technique features: stroke timing and upper limbs orientation during the finish phase.

Desempenho produtivo da tilápia do nilo em tanques-rede numa represa pública: modelo empírico de classificação

Nos últimos anos, a piscicultura brasileira em tanques-rede, em águas públicas abertas, tem sido alavancada por incentivos governamentais e privados, e a tilápia do nilo (Oreochromis niloticus) tem sido o principal pescado utilizado. Como forma de melhorar a eficiência de produção, empiricamente, os piscicultores realizam o manejo de classificação e a repicagem das tilápias em engorda, resultando em lotes com diferentes rendimentos e precocidades, num gradiente dos melhores aos piores rendimentos. Este trabalho objetivou avaliar o desempenho de engorda de tilápias em um rotineiro sistema de produção em tanques-rede, sendo utilizado o usual modelo empírico de classificação e repicagem em três etapas distintas e tendo por fundamento a separação dos lotes de peixes em classes de tamanho e peso, ao longo do processo de engorda. Os resultados mostraram situações bem distintas. Num extremo, lotes de peixes precoces sendo comercializados após o processo de classificação e repicagem, aos 152 dias de engorda, apresentando taxas crescentes de ganho de peso diário (entre 0,30 e 7,23g dia-1) e de conversão alimentar aparente satisfatória (entre 1,50 e 1,53). No outro extremo, lotes heterogêneos sendo comercializados com 213 dias, taxas de ganho de peso inconstantes (entre 0,94 e 8,24) e elevadas taxas de conversão alimentar aparente (entre 1,54 e 3,03). A partir dos resultados, pode-se destacar a relevância dessa prática empírica de manejo zootécnico em piscicultura, que mostra grandes discrepâncias de rendimentos e precocidades entre os lotes, considerando o tempo de cultivo, o ganho de peso e a conversão alimentar aparente. Além disso, recomenda-se, para os lotes heterogêneos destinos, alternativas como a utilização de piscicultura extensiva (sem arraçoamento) para a mitigação dos impactos ambientais negativos inerentes dessa atividade zootécnica.

Response of austenite finish temperature and phase transformation characteristics of thin medical-grade Ni–Ti wire to short-time annealing

Short-time annealing is commonly applied as shape setting or passivation treatment on Ni–Ti wire. Its influence on the austenite finish (Af) temperature and the martensite–austenite transformation characteristics has been investigated in detail using a newly constructed device implementing a bend and free recovery test with high resolution. Short-time annealing at 450–600 °C can shift the Af temperature from ΔAf = +25 to −15 K and can render the phase transformation either one-stage or two-stage.

Effects of regrouping on the individual behavioural characteristics of pigs

The behaviour of an animal is a combination of that which is inherited and that which is influenced by the environment. This study was conducted to determine a means for assessing and distinguishing individuals based on behavioural characteristics and to better understand the environmental impact on behavioural trait changes in pigs. Eighty-nine pigs (nine litters) were followed from birth until the end of the grow–finish period. All litters remained intact until four were mixed when they entered the grow–finish phase. Data on general activity, social behaviour, average daily gain and injury scores were collected throughout the entire experimental period. When the pigs were still with the sow, we also collected data on teat order consistency, suckling and suckling bouts. The pigs were subjected to a series of behavioural tests when in the nursery and grow–finish phases. The data were subjected to a factor analysis to determine individual behavioural traits. The effect of regrouping was determined by using an analysis of variance, comparing scoring coefficients of pigs that either remained intact or were regrouped. Three primary factors were identified and interpreted as indicating levels of approachability, exploration, and aggression. Regrouped and intact treatments only differed in level of approachability. The intact litters followed a typical habituation response to repeated exposures of a novel arena test. However, the pigs in the regrouped litters consistently took longer to approach a human and novel object. This suggests that the trauma caused by regrouping resulted in a generalisation of fear associated with an environmental change.

Digestibilidade da ração de frangos de corte suplementados com probióticos e antibiótico

O objetivo deste experimento foi avaliar a digestibilidade da ração de frangos de corte a qual continha ou não antibiótico e probióticos na fase inicial (um a 20 dias) e na fase final (21-40 dias). As aves foram distribuídas em um delineamento inteiramente casualizado com quatro tratamentos: Tratamento 1- Dieta Testemunha; Tratamento 2 - Dieta Testemunha + 0,02 % de probiótico 1 (Calsporin 10®), Tratamento 3 - Dieta Testemunha + 2,0% na fase inicial e 0,63% na fase final de probiótico 2 (Estibion aves®); Tratamento 4 - Dieta Testemunha + 0,013% de antibiótico (Bacitracina de Zinco®) e 5 repetições de 10 e 8 aves por unidade experimental por fase, respectivamente. Os pintos foram criados em gaiolas de metabolismo. Os resultados demonstram que a digestibilidade de matéria seca, nitrogênio e energia metabolizável aparente não foi afetada pela suplementação de antibiótico e probióticos na dieta de frangos de corte.

Níveis de concentrado e proteína bruta na dieta de bovinos Nelore nas fases de recria e terminação: consumo e digestibilidade

Avaliaram-se os consumos e as digestibilidades aparentes dos nutrientes de dietas fornecidas para bovinos Nelore nas fases de recria e terminação. Foram utilizados 32 novilhos Nelore não-castrados, com peso médio de 240 kg, confinados em baias individuais, na fase de recria, e 16 novilhos com peso médio de 360 kg, na fase de terminação. Após a pesagem, os animais foram distribuídos em esquema fatorial 4 x 2 (quatro níveis de concentrado x dois níveis de proteína), com quatro repetições por tratamento na fase de recria e duas repetições na fase de terminação, em delineamento inteiramente casualizado. Os quatro níveis de concentrado utilizados nas dietas foram 20, 40, 60 e 80% e os dois níveis de PB, 15 e 18%, na base da MS, utilizando-se o feno de capim-Tifton 85 como volumoso. Os teores máximos de NDT de 72,33% foram estimados com 40,40% de concentrado e não houve efeito dos teores de proteína bruta das dietas sobre as digestibilidades dos nutrientes na fase de recria. Na fase de recria, os consumos de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB) e carboidratos totais (CHOT) máximos de 7,60; 7,23; 1,30; e 5,77 kg/dia foram estimados para 45,94; 46,94; 40,91; e 48,18% de concentrado, respectivamente. O consumo da FDN apresentou redução linear com o aumento do nível de concentrado na dieta, enquanto a digestibilidade da FDN não foi alterada. Na fase de terminação, os consumos de MS, PB, FDN e FDA foram reduzidos linearmente com o aumento dos níveis de concentrado, enquanto os consumos de MO, CHOT e NDT não foram influenciados; as digestibilidades da MS e CHOT aumentaram linearmente, enquanto as da PB e EE não foram influenciadas pelos níveis de concentrados nas dietas.

Effect of nutrition, age and size on compensatory growth in two breeds of steers.

Compensatory gain in cattle was studied to determine if age, previous rate of gain or size were factors of importance. A factorial experiment was conducted with growing diet regimen (control vs restricted), age [spring-born (older) vs fall-born (younger)] and breed (Angus vs Charolais) as the factors. During a growing phase, the two diets, (control = dehydrated alfalfa pellets; restricted = cubed grass-alfalfa hay, cottonseed hulls and soybean meal) were fed to both the older and younger steers of each breed to provide groups of similar age but different weights (growing regimen within age) and groups of similar weights but different ages (older-restricted vs younger-controls) at the time at which the steers were switched to a high concentrate diet. Interactions of breed with age and previous growing regimen diet on digestibility of some nutrients in the finishing diet were evident. During the growing phase, control steers averaged .72 kg/d gain, whereas the restricted steers averaged .25 kg/d. The older-restricted steers compensated (P less than .05) from 30 to 120 d after the beginning of the feedlot phase compared with older-control steers. Rates of gain of younger steers were intermediate to those of the older steers throughout the finish phase and were not influenced by growing diet, except on d 30. Rate of gain during the growing phase was negatively correlated (P less than .05) with rate of gain during the finishing phase (60 to 120 d). Within breed, weight at the beginning of the feedlot phase also was negatively correlated with gain during the finishing phase. Skeletal growth was reduced (P less than.05) by the restricted diet during the growing phase, and small compensation (P greater than .05) was observed during the finishing phase. Feed/gain for restricted steers was slightly lower (P greater than .05) than control steers. Younger steers were more efficient (P less than .05) overall in converting dry matter to gain, due to the relatively shorter growing phase when compared with the older steers. These data indicate that both previous gain and weight upon realimentation are influential on compensatory growth.