Danielthyssen6214

ntation improved feed conversion and survival during chronic cyclic heat stress, which may be associated with enhanced breast muscle energy status and arginine sparing effect.An experiment was conducted to investigate the effects of dietary pantothenic acid levels on growth performance, carcass traits, pantothenic acid status, and antioxidant status of male white Pekin ducks from 15 to 42 D of age and to evaluate the requirement of this vitamin for growing ducks. Different levels pantothenic acid (0, 2, 4, 6, 8, and 10 mg/kg) were supplemented to a corn-soy isolate protein basal diet to produce 6 dietary treatments with different analyzed total pantothenic acid levels (4.52, 6.44, 8.37, 9.88, 12.32, and 14.61 mg/kg). A total of 240 15-day-old male white Pekin ducks were allotted to 6 dietary treatments with 8 replicate pens of 5 birds per pen. At 42 D of age, growth performance, carcass traits, tissue pantothenic acid concentrations, and antioxidant status of white Pekin ducks were examined. Significant effects of dietary pantothenic acid on BW, average daily weight gain (ADG), plasma, and liver pantothenic acid concentrations were observed (P less then 0.05) but not carcass traits. The growing ducks fed the basal diet without pantothenic acid supplementation had the lowest BW, ADG, plasma, and liver pantothenic acid content among all ducks (P less then 0.05). In addition, the ducks fed the basal diet without pantothenic acid supplementation showed the lowest antioxidant capacity indicated by greatest plasma malondialdehyde content and lowest liver total antioxidant capacity (P less then 0.05). And, these criteria responded linearly as dietary pantothenic acid levels increased (P less then 0.05). These results indicated that dietary pantothenic acid supplementation improved growth performance and antioxidant status of the growing ducks. In accordance with the broken-line model, the pantothenic acid requirements (based on dietary total pantothenic acid) of male white Pekin ducks from 15 to 42 D of age for BW, ADG, and plasma and liver pantothenic acid contents were 10.18, 10.27, 12.06, and 10.79 mg/kg, respectively.Understanding energy partitioning in broiler breeders is needed to provide efficiency indicators for breeding purposes. This study compared 4 nonlinear models partitioning metabolizable energy (ME) intake to BW, average daily gain (ADG), and egg mass (EM) and described the effect of BW and rearing photoperiod on energy partitioning. Ross 708 broiler breeders (n = 180) were kept in 6 pens, controlling individual BW of free run birds with precision feeding stations. Half of the birds in each chamber were assigned to the breeder-recommended target BW curve (Standard) or to an accelerated target BW curve reaching the 21-week BW at week 18 (High). Pairs of chambers were randomly assigned to 8L16D, 10L14D, or 12L12D rearing photoschedules and photostimulated with 16L8D at week 21. Model [I] was MEId = a × BWb + c × ADG × BWd + e × EM + ε, where MEId = daily ME intake (kcal/day); BW in kg; ADG in g/day; EM in g/day. Models [II-IV] were nonlinear mixed versions of model [I] and included individual [II], age-related [r breeders including an age-related random term.This study aimed to evaluate the effects of different egg turning frequencies on incubation efficiency parameters. Nine hundred sixty brown fertile eggs, with an average weight of 52.20 ± 0.85 g, from 38-week-old CJD (Carijó Pesadão) breeder hens were randomly distributed among 4 treatments before incubation. Each treatment corresponded to a turning frequency, being 24 (control), 12, 6, or 3 times per day, at an angle of 45°, until day 18 of incubation. The experimental design was a randomized complete block design with 4 treatments. Analysis of the incubation parameters was based on 6 replications per treatment. The eggs that were turned 12, 6, and 3 times per day exhibited a decrease in hatchability of the fertile eggs of 6.61, 15.51, and 19.70%, respectively, when compared with the control group (91.84 ± 2.73%). With a decrease in turning frequency, there was a gradual increase in early (2.84 ± 1.89 to 14.31 ± 1.82%) and late (3.57 ± 1.39 to 8.05 ± 1.24%) mortality rates. An egg turning frequency of 24 times per day during incubation provided high hatchability rates. Selleckchem BBI608 In contrast, the turning frequencies of 12, 6, and 3 times per day showed significant losses in hatchability.This study investigated how the carbon dioxide (CO2) concentration within a chamber affects the efficacy of CO2 euthanasia and how the efficacy of CO2 induction methods changes as birds age. In experiment 1, pairs of broiler chicks (n = 192; 0, 3, and 6 D of age) were immersed into a chamber prefilled with 70, 80, 90, or 100% CO2. For experiment 2, 3- and 6-day-old broiler chicks (n = 88) were immersed in pairs into 100% CO2 or exposed to CO2 gradual fill in a chamber with a displacement rate of 28% chamber volume per minute. Latency to performance of headshaking (HS) and gasping (GS) as potential indicators of distress, loss of posture indicative of insensibility, and the cessation of rhythmic breathing (CRB) and cessation of movement (COM) as the indicators of death were monitored (live focal sampling/video recordings). The duration and frequency of HS and GS were assessed. For both experiments, behavior data were analyzed for CO2 method and age (4 × 3 factorial). Age and CO2 concentration interacted for latency to CRB and COM, with longer latencies for 0-day-old chicks immersed into 70% CO2 than other concentrations and ages. CO2 concentration did not affect latency to HS, GS, or loss of posture but affected CRB and COM, with latencies longest for 70% and shortest for 90 and 100% CO2. Newly hatched chicks had a longer latency to CRB and COM and longer duration and frequency of distress behaviors than older chicks. At all ages, initiation of all behaviors occurred later with gradual fill compared to immersion. There was an increased duration and frequency of distress behaviors with gradual induction compared with immersion. Overall, immersion into 90 to 100% CO2 resulted in the shortest time to insensibility and death, with a decreased duration and frequency of distress behaviors. Chicks immersed into 70% CO2 had the longest duration of GS and time to death. Age affects the efficacy of CO2 euthanasia, with increasing age decreasing time to death and the duration and frequency of distress behaviors.Consumer concern for broiler welfare has increased interest in chicken from slower growing (SG) broiler strains. Broilers from SG strains take longer to reach market weight, which may necessitate differences in management practices, such as stocking density. This study evaluated the effects of 2 stocking densities on production performance, body conformation, and welfare of broilers from 2 strains. Broilers from strains that reach market weight at age 42 D (CONV; N = 284) and at 63 D (SG; N = 284) were exclusively stocked into pens at a density of either 29 kg/m2 or 37 kg/m2. Birds were provided the same starter, grower, and finisher diets with diet phase changes occurring when SG bird body weight (BW) matched CONV. Live BW, body length, pelvic width, shank length, shank width, keel length, breast width, and breast depth were collected at 4 phases Phase 1-chick placement, Phase 2-starter, Phase 3-grower, and Phase 4-finisher. At Phase 4, footpad dermatitis (FPD), hock burn (HB), and toe damage (TD) were scored. Feed conversion ratio (FCR) and mortality for each pen were recorded throughout the study. Final BW was similar (2.68 kg) for both strains and stocking densities of birds (P > 0.05). CONV bird FCR was 35% more efficient than SG (P less then 0.0001). CONV birds had shorter bodies and shanks compared with SG birds at Phases 3 and 4 (P less then 0.05). Slower growing birds stocked at 37 kg/m2 had the longest bodies and keel bones at Phase 4 (P less then 0.01). Also at Phase 4, SG birds stocked at 29 kg/m2 had the lowest prevalence of HB (4%), yet the highest prevalence of TD (28%; P less then 0.01). These results indicate differences in the effects of strain and stocking density on male broiler conformation, performance, and welfare and highlight the importance of tailoring management practices to the strain of broiler raised.The present work was carried out to investigate the influences of housing system and dietary essential oils (EOs) supplementation to laying hens on the productive performance, egg quality, immunity, antioxidant parameters, and hematology. A factorial arrangement (2 × 4) was performed, including 2 housing systems and 4 different types of EOs (without EOs, thymol, carvacrol, and euganol) during the production stages (from 28-78 wk of age). Birds were randomly divided into 2 groups with each of 2,000 birds. The first group was moved to laying cages while the second group was a floor reared. Each group was randomly divided into 4 groups (5 replicates of 100 birds each) The first were considered as a control group, and the second, third, and fourth groups were treated with thymol, carvacrol, and euganol EO, respectively. The results showed that hens reared in cage system had higher egg weight (P 0.05) by housing system. The groups fed EOs showed a rapid improvement (P less then 0.001) in the egg production%, egg weight, egg mass, and egg quality. Thymol group had the highest egg production (P less then 0.001). Thymol and eugenol groups had the highest egg weight, egg mass, and egg quality (P less then 0.001). The groups fed diets containing thymol or eugenol consumed lower feed and had better feed conversion ratio (P less then 0.001) than the control group. Immunity indices (phagocytic activity [P less then 0.05], avian influenza [AIH5 and AIH9], P less then 0.001) were improved with the presence of EOs in the laying hen diet. These results strongly suggest that dietary EO supplementation could be a successful attempt to improve the productive performance, egg quality, and immunity of laying hens.Effects of dietary Original XPC (XPC) on 17 selected blood variables in commercial layer pullets challenged with the virulent, low-passage R strain of Mycoplasma gallisepticum (RlowMG) were investigated. Hy-Line W-36 pullets sourced from M. gallisepticum-clean layer breeders were fed a basal diet with XPC (1.25 kg/metric ton) or without from hatch until 12 wk of age (woa). At 8 and 10 woa, half of the birds in each dietary treatment were challenged with RlowMG. Blood samples were taken immediately before the initial RlowMG challenge at 8 woa and again at 12 woa (4 wk after challenge). At 8 woa, blood pH was lower and glucose concentration was higher in the preassigned challenge treatment groups. At 12 woa, the concentration of oxygen dissolved in the blood was significantly lower in the RlowMG-challenged group than the unchallenged group of birds regardless of dietary treatment. The RlowMG challenge significantly increased blood carbon dioxide partial pressure, calcium, sodium, anion gap, osmolality, glucose,ory acidosis. Nevertheless, feeding XPC did not influence the effects of challenge treatment on these postchallenge physiological blood values.The immunological immaturity of the innate immune system during the first-week post-hatch enables pathogens to infect chickens, leading to the death of the animals. Current preventive solutions to improve the resistance of chicks to infections include vaccination, breeding, and sanitation. Other prophylactic solutions have been investigated, such as the stimulation of animal health with immunostimulants. Recent studies showed that administration of immune-modulators to one-day-old chicks, or in ovo, significantly reduces mortality in experimental bacterial or viral infection challenge models. Owing to a lack of molecular biomarkers required to evaluate chicken immune responses and assess the efficacy of vaccines or immune-modulators, challenge models are still used. One way to reduce challenge experiments is to define molecular signatures through omics approaches, resulting in new methodologies to rapidly screen candidate molecules or vaccines. This study aims at identifying a dual transcriptomics and metabolomics blood signature after administration of CpG-ODN (cytosine-phosphate-guanine oligodeoxynucleotides), a reference immune-stimulatory molecule.