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ABSTRACT This experiment was conducted to evaluate the effect of egg weight and egg physical characteristics on embryonic development, hatchability, and hatchling weight of Japanese quails (Coturnix coturnix japonica). In total, 689 eggs were classified in two categories: small (<13.5 g) or large (≥13.5 g), and different external eggshell and internal quality traits were measured. On days 6 and 14 of incubation, tissue triiodothyronine (T3) and thyroxine (T4) were extracted from embryos in both egg sizes and analyzed. Relative to internal egg-quality traits, large eggs had significantly higher yolk height, yolk diameter, yolk weight, albumen height, and albumen weight than small eggs (p≤0.01). However, Haugh unit score (p=0.27) was not significantly different between the two egg sizes. Relative to eggshell quality parameters, large eggs had significantly higher total pore count, surface area, eggshell volume, and eggshell weight than small eggs (p≤0.05), with consequent higher hatchability rate and hatchling weight. Pearson’s correlation coefficients revealed significant correlations (p≤0.05) between egg weight and different external and internal egg quality parameters. Thyroid hormone levels were not significantly different between egg groups on d 6 day, while on d 14, a significant difference was recorded (p≤0.05). In conclusion, larger egg sizes are recommended to obtain better hatchability, lower embryonic death rates, and heavier hatchlings compared with smaller eggs of Japanese quails.

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ABSTRACT The effects of three egg-turning regimes during the pre-incubation storage period on egg weight loss, hatchability, embryonic mortality, chick weight at hatching and incubation length of red-legged partridge (Alectoris rufa) compared with unturned eggs were investigated. Two hundred eggs were allocated to four 50-egg batches stored at 15ºC and 80% RH that being turned one, four and 24 times a day or remaining unturned, respectively. Eggs were incubated at 37.8ºC and 55% RH during the first 21 days and at 37.5ºC and 75% RH until hatching. Fertility was 70.5% and a good hatchability performance was obtained, characterised by 81.6% hatchability of fertile eggs, and weight losses of 0.78% during storage and of 10.04% during the first 21 days of incubation, 13.6 ±0.1 g hatchling weight, and incubation length of 23.45 ± 0.07 days (mean ± SEM). Hatchability, embryonic mortality developmental stage, egg weight loss during storage and incubation, hatchling weight and length of the incubation period were not affected by the turning frequency or the absence of turning during storage. Higher hatching synchrony was observed for eggs turned four times a day compared with unturned eggs and eggs turned once a day. In conclusion, turning red-legged partridge eggs during medium-term storage periods does not improve egg viability compared with unturned eggs.

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ABSTRACT To investigate the hypothesis that APS can attenuate E. coli-induced microvascular dysfunction in chicken intestine, 60 0-day old male chickens were divided into three groups with 5 replications of 4 chicks. Chicken in the APS group were treated with 15 mg APS daily while the others were given 0 mg APS for 6 days. Then all 7-day old chicken were injected intraperitoneally by E. coli, except for the chicken in the control group. After 4 h, all chicken’s intestinal samples were collected to detect gene expressions involved in inflammatory factors and adhesion molecules. Results showed that APS attenuated the signs of edema and hemorrhage in 7-day old chicken intestinal mucosa which were induced by E. coli injection. Consistently, APS significantly reduced the increasing mRNA levels of inflammatory factors such as Tumor necrosis factor-a (TNF-a), interleukin (IL) -1β and inducible nitric oxide synthase (iNOS) (p<0.05), the same results were observed in vascular adhesion molecules such as E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Moreover, we observed that APS supplementation in water suppressed significantly (p<0.05) the decline of reparative factors such as epithelial growth factor (EGF) and basic fibroblast growth factor (bFGF) in E. coli injected group. Furthermore, supplementation with APS substantially blocked (p<0.05) the increase in Toll-like receptor-4 (TLR4) and Nuclear factor (NF)-κB mRNA abundance (p=0.087) induced by E. coli infection. This study indicated that microvascular injured chicken intestine induced by E. coli would be attenuated with feeding APS, and the mechanism of repairing were probably mediated through TLR4-NF-κB signal pathways.

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ABSTRACT The poultry nutritionists constantly attempt to identify and alleviate the factors responsible for adverse effects on nutrient utilization and production performance in avian species, which are necessary for successful productivity of poultry. Enhanced feed utilization can reduce levels of some nutrients in the diet with concomitant mitigation in nutrient excretion into the environment, reduction of eutrophication and acidification potentials of excreta. Commercial enzymes have been used to improve feed efficiency and utilization in poultry. Among many anti-nutritional factors, the existence of ß-mannans in poultry feed ingredients including soybean and other leguminous seeds has been associated with negative effects on nutrient digestibility and high intestinal viscosity that adversely affects innate immunity and microbial proliferation in poultry gut. The ß-mannanase (a commercial product named as Hemicell) can hydrolyze ß-mannan, an anti-nutritional fiber present in many poultry feed ingredients. Supplement of ß-mannanase to ß-mannan-rich diets may boost the population of intestinal beneficial bacteria, increase the digestibility of mannans, enhance the immunity, suppresses the growth of harmful intestinal bacteria, enhance the digestion and absorption of nutrients in intestinal tracts and reduce the environmental pollution due to poultry excreta. Supplementation of β-mannanase at the level of 200 and 400 mg/kg in poultry diets has positively improved blood glucose and anabolic hormone homeostasis, FCR, digestible energy, and digestible amino acids. This review describes the promising beneficial effects of β-mannanase, which may be used in the poultry feed industry for economic benefits. Another objective of this review is to explore the underlying mechanisms of ß-mannanase that can influence growth, digestion coefficients of nutrients, health and metabolism of nutrients in poultry birds and also the knowledge regarding the useful application of this feed enzyme in the commercial poultry feed industry.

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ABSTRACT About 33.3% of chicken life is conditioned by the result of embryonic development. Therefore, understanding and improving the early phase of the broiler’s life is critical to guarantee their well-being. Thus, the objective of this research was to evaluate the relationship between the breeder’s age, breed and the incubator types on quality and animal welfare in the hatchery. The experimental design was completely randomized in a 2 x 2 x 3 factorial arrangement (incubator, breed and age), with 12 treatments and 6 replicates each. The eggs derived of Cobb 500 and Ross’s breeders at the beginning of the laying period, middle age and at the end of the laying period. It is concluded that the size of the eggs is related to the breeder’s age and breed, which influences directly the number of bled eggs. In addition, well-being in the hatchery can be affected by decreased hatching and contamination that is higher in older breeders. Cobb eggs also need more attention because they are larger, therefore, they have a higher risk of breakage and they are more sensitive to the low concentration of CO2 at the hatcher.

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ABSTRACT This work aimed to develop chicken meatballs with five levels of animal fat replacement by canola oil and to evaluate the product’s behavior during 120 days of storage. For that, analyzes were performed in the centesimal composition, fatty acid profile, shelf life and sensory parameters. The centesimal composition of the product did not present significant difference (p>0.05) between the treatments. However, canola oil addition improved the lipid profile, atherogenic and thrombogenic indexes, and the ratios of PUFAs/SFAs (0.91 to 1.61) and n6/n3 (12.63 to 3.74) in the products. Animal fat replacement and storage time also reduced meatballs Aw and pH. No differences in texture between treatments were detected after 30 days of storage. The lipid oxidation presented by mean values ​​of TBARs ranged from 0.71 and 1.35 mg MDA/kg, indicating the onset and the regression of lipid oxidation. The color parameters exhibited a spectrum towards the luminous yellow color, predominant in both chicken meat and canola oil. The results of this study indicate that the substitution of animal fat by canola oil is promising in the production of meat products with good acceptability (70%) during the sensory analysis.

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ABSTRACT The objective of the study was to investigate the mechanism by which dietary energy concentration regulates laying performance in geese. Eighty 558-day-old female Sichuan White geese were randomly allotted to two dietary treatments, each treatment was fed 1 of 2 experimental diets containing 10.00 (deficient) or 11.80MJ/kg metabolizable energy (sufficient) for 30 days. Laying performance, hormone concentration and gene expressions in hypothalamus-pituitary-gonadal axis were examined in geese. Birds fed the sufficient-energy diet had significantly higher average egg weight, daily laying rate, and lower feed to egg ratio than those fed the deficient-energy (p<0.05). The birds fed sufficient-energy diet had higher concentration of serum insulin like growth factor 1 (IGF-1), gonadotropin-releasing hormone (GnRH), follicle-stimulating hormone (FSH) and estradiol (E2) than those in deficient-energy diet (p<0.05). The mRNA expression levels of GnRH in the hypothalamus, FSH in the pituitary and E2 in the ovary of birds fed sufficient-energy diet were higher than the corresponding counterpart in deficient-energy diet (p<0.05), respectively. In conclusion, the study implied that dietary energy modifies laying possibly through regulating reproductive hormone secretion and gene expression in hypothalamus-pituitary-gonad axis in laying geese.

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ABSTRACT Gallibacterium anatis, a member of the Pasteurellaceae family, leads to decrease in egg-production, animal welfare and increase in mortality. This study aimed to diagnose G. Anatis, which caused economic losses in laying hens by using conventional and molecular techniques. In this study, G. anatis was examined from a total of 200 dead chicken tissues (heart, liver, lung, spleen and trachea) in laying hen farms that observed a decrease in egg production with respiratory system infection. Conventional methods based on colony morphology, sugar fermentation tests and hemolytic properties and molecular conformation using 16S rRNA-23S rRNA specific primers were performed to identify G. anatis. G. anatis was isolated in 20 (10%) of the examined samples and isolates were confirmed by conventional PCR. A total of 11 (2.2%) positivity was obtained as isolates were the result of PCR performed on tissues and organs directly. As a result, the presence of G. anatis was detected for the first time in Turkey by this study. It was thought that G. anatis may have a role in egg production losses due to respiratory tract infection in poultry and this situation may be a guide for poultry clinicians and microbiologists.

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ABSTRACT Dietary inclusion of lipid sources has been one of the methods adopted by nutritionists aiming at better energy balancing. However, alternative energy feedstuffs have been sought in an attempt to reduce production costs. In this regard, lipid sources that can replace conventional ones, such as beef tallow, cottonseed oil, and sunflower oil have been investigated. The objective of this study was to examine the effects of different lipid sources on the performance, egg quality, biometrics of digestive organs, and bone quality of white-egg commercial layers in the first production cycle. A total of 216 Hy-Line White layers at 70 weeks of age, weighing 1.701 ± 0.103 kg, were used in a completely randomized design with four treatments and six replicates. The diets provided to them contained equal amounts of protein, calories, and amino acids, with only the lipid source varying - soybean oil (control), cottonseed oil, beef tallow, and sunflower oil. No significant effect of lipid sources was observed on any of the performance or egg-quality variables assessed (p>0.05). Biometric variables were not influenced by lipid sources, except for abdominal fat, which was highest in the birds receiving the beef-tallow treatments and lowest in birds fed the sunflower-oil diets (p<0.05). Except for mineral matter, bone traits were not influenced by the treatments; this variable was highest in the control treatments and lowest in the beef-tallow treatments. In conclusion, cottonseed and sunflower oils can be used to fully replace soybean oil in diets for white-egg commercial layers.

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ABSTRACT This study investigated the effects of incubator carbon dioxide (CO2) and oxygen (O2) levels, and egg weight (EW) on embryo mortality (EM) and hatchability of fertile eggs (HFE). A total of 1920 hatching eggs were obtained from a middle-aged (41 weeks) ROSS 308 broiler breeder flock. The eggs were classified according to EW as heavy (69.63 ± 0.09 g), medium (65.20 ± 0.04 g) and light (61.11 ± 0.08 g) and randomly allocated to four separate identical incubators. To these incubators, four different incubator ventilation programmes (IVP) classified as control (C; 0.7% CO2 and 20.9% O2), high CO2 (HC; 1.1% CO2 and 20.3% O2), high O2 (HO; 0.6% CO2 and 22.0% O2), and high CO2 + O2 (HCO; 0.9% CO2 21.0% O2) were applied, and EM and HFE were examined. IVP affected EM and HFE; a higher rate of early EM and a lower rate of HFE were obtained from the HO group compared to the HCO group, and a lower rate of HFE was observed in the HO group than to the C group (p<0.05). An association was found between EW and IVP (p<0.05), being more evident in early EM for light eggs. Consequently, IVP; i.e., different CO2 and O2 levels in the incubator affected the hatching results. This is considered to be due to the altitude of the experiment (724m) and the uniform eggs being obtained from the same middle-aged flock, and incubator O2 levels should be taken into consideration, as well as CO2.

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ABSTRACT Photoperiod and nutrition are major factors that affect the reproductive efficiency particularly in female animals. In this study we examined the interaction of photoperiod and food restriction on growth, sexual maturation and receptor mRNA expressions of leptin, melatonin, and estrogen in abdominal fat and the ovary of pullets. There were no interaction effects between photoperiod and feeding level on body weight, abdominal fat weight, ovary weight at both 14 wk and 18 wk. Abdominal fat weight of feed restriction group was significantly lower compared with the control group at the age of 14 wk, 18 wk, and age of the first egg (AFE) (p<0.05). Ovary LEPR (Leptin receptor) gene expression showed an interaction effect of the first egg. Restricted feeding significantly inhibited ovary ER (Estrogen receptor), LEPR and MELR1B (Melatonin 1B receptor) gene expression at 14 wk, 18 wk and the first egg. At 14-week-old, abdominal fat LEPR gene expression was significantly lower in long photoperiod group compared with the short photoperiod group. At the first egg, short photoperiod and feed restriction group reduced abdominal fat LEPR gene expression. The results indicated that the reproductive activity of pullets is sensitive to feed intake and photoperiod. Feed restriction down regulated the ER, LEPR, MELR1A (Melatonin 1A receptor) and MELR1B mRNA expression of the ovary at 14 wk, 18wk and AFE. Long photoperiod enhanced the LEPR, MELR1A and MELR1B mRNA expression of abdominal fat at AFE.

Resumo em Inglês:

ABSTRACT The study was planned to evaluate the effect of different naked-neck (NN) chicken genotypes and breeder ages on the growth performance of their progenies. A total of 126 chicks, from two breeder ages and three NN varieties, were reared up to 20 weeks of age. A randomized complete block design in factorial arrangement, with six treatments of seven replicates of two females and one male each, was applied. Treatments consisted of three NN varieties (light brown, black, and dark brown) and two breeder age groups (45 and 55 weeks old). Growth performance (body weight gain, feed intake and feed conversion ratio) were evaluated. Higher feed intake was observed in both the male and female progenies of 55-week-old compared with 45-week-old breeders. Light brown males had higher weight gain than dark brown males, whereas in the female progeny, higher weight gain was obtained in the black variety than that in the light brown and dark brown varieties. Regarding breeder age groups, both male and female progenies of 55-week-oldbreeders exhibited higher weight gain than those of 45-week-old breeders. The male progeny of 55-week-old black breeders showed the highest body weight gain among all treatments. Regarding female progeny, higher weight gain was observed in the black variety compared with the light brown and dark brown variety, and in the progeny of 55-week-old breeders than in the progeny of 45-week-old breeders. The interaction between factors showed that females from 55-week-old black breeder has the highest weight gain, whereas the lowest weight gain was found in the progeny of 45-week-old light brown breeders. The male progeny of light brown breeders showed better FCR than those of black and dark brown breeders and of 55-week-old breeders compared with that of 45-week-old breeders. The best FCR was obtained in the progeny of 55-week-old light brown breeders. In females, while no influence of breeder age was detected, better FCR was determined in black than in dark brown and light brown varieties; however, the interaction between factors was significant, with the best FCR obtained in the female progeny of 55-week-old black breeders, and worst in the progeny of 45-week-old light brown breeders. In conclusion, the light brown and black varieties of naked-neck chickens and the progeny of 55-week-old breeders presented better growth performance.

Resumo em Inglês:

ABSTRACT Feed formulation using linear programming consists of determining the mixture of feedstuffs required to meet pre-established animal nutritional requirements at the lowest cost. On the other hand, with the use of non-linear programming, it is possible to define nutritional requirements at the time of formulation, aiming at maximum profit. The objective of the present study was to compare feeds formulated using linear and non-linear programming in terms of live performance and internal and external egg quality of commercial laying hens. A total of 288 Hisex® White laying hens, 1.540 ± 0.128 g body weight, were evaluated from 33 to 45 weeks of age. Hens were distributed in a completely randomized block design, including six treatments with six replicates of eight birds each. Three treatments consisted of feeds formulated using linear programming and based on the nutritional requirements of Rostagno et al. (2011), of the genetic strain manual, or mathematical models to maximize performance. The other three treatments consisted of feeds formulated using non-linear programming considering typical, favorable, or unfavorable market scenarios. Data were submitted to analysis of variance, and in case of significance (p<0.05), means were grouped using the Scott-Knott test (5%).The treatments did not influence (p>0.05) Haugh unit, albumen height, or external egg quality parameters. Treatment effects (p<0.05) on yolk weight, albumen weight, yolk color, yolk percentage, albumen percentage, and performance parameters were described. In general, feeds formulated using linear programming and based on nutritional requirements obtained by mathematical models and the genetic strain manual promoted better performance results because the feeds were nutritionally denser. However, the treatments that maximized live performance did not result in higher profitability, which was obtained with the diet formulated for a favorable market scenario using non-linear programming.

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ABSTRACT The melanocortin 1 receptor (MC1R) gene plays a key role in controlling the deposition of melanin. In mammals, the MC1Rgene is regarded as a major candidate gene in the control of melanin formation. In domestic animals, the MC1R gene mainly controls the expression of coat, skin, and plumage color in mammals and birds. In order to breed chickens with dark-green shank faster, we screened the molecular markers for shank color in a HS chicken population by exploring the relationship between polymorphism of the MC1R gene and three different shank colors (light green, dark green and yellow). Two primer pairs for code region of the MC1R gene were designed in the basic of chicken genomic sequence. DNA sequencing was performed to detect the polymorphisms and PCR was used to amplify DNA fragment. Sequences analysis indicated that 7 SNPs were predominant the three HS chicken populations with different shank color, including g.18,287,945C>T, g.18,288,088T>C, g.18,288,150G>A, g.18,288,303A>G, g.18,288,512G>A, g.18,288,513T>C, and g.18,288,520A>C. Association analysis revealed that the dark-green shank population showed moderate polymorphism, whereas the light-green shank population showed low polymorphism among overall 7 SNPs and that SNP6 (g.18,288,513T>C) may be significantly associated with three different shank colors in HS chickens. The haplotype CTGGACA had the largest haplotype frequencies, accounting for 56.22%, and the haplotype combination H1H1 is mainly distributed in the dark-green shank population, and may be used as molecular maker for marker-assisted selection of shank color in HS chickens.

Resumo em Inglês:

ABSTRACT The objective of this study was to compare characteristics and properties of breast meat from spent Lohmann Brown layers (SP, 90 weeks old, n = 24) and those of commercial broilers (BR, 6 weeks old, n = 24). The breasts of both SP and BR were collected from a local processing plant, vacuum-packed in a plastic bag, and stored at -18ºC until further analyses. The SP showed a greater water-holding capacity, tougher and chewier texture (p<0.05). Both raw and cooked SP breasts comprised the greater total collagen but lower soluble collagen than those of BR (p<0.05). Muscle fibers of the SP, observed under scanning electron microscope, were small, with average fiber diameter of 37.85±1.40 μm, densely packed and surrounded by complex networks of connective tissue. The lower myofibril fragmentation index and alkaline-soluble protein fractions of the SP (p<0.05) suggested lesser degree of postmortem fragmentation and protein denaturation in SP compared to BR. Based on differential scanning calorimetry, multiple endothermic transitions were observed in both raw BR and SP breast samples. While BR thermograms comprise five transitions at 57.7ºC, 64.2ºC, 67.6ºC, 72.3ºC and 77.6ºC with total ΔH of 15.31 J/g dry meat, the SP samples exhibited four transitions at 55.1ºC, 62.1ºC, 70.5ºC and 77.7ºC and total ΔH of 17.62 J/g dry meat. Overall, the findings indicated that cooked meat toughness of SP was attributed by the high total and heat-stable collagen content, densely packing of small muscle fibers, and the superior myofibril integrity.

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ABSTRACT This study aims to evaluate the possibility to formulate low-sodium bicarbonate-marinated turkey breast meat. In total, 60 meat cuts (100 × 50 × 30mm) were divided into four treatments: B1 (0.5% sodium bicarbonate and 0% sodium chloride replacement), B2 (0.5% sodium bicarbonate and 15% sodium chloride replacement), B3 (0.5% sodium bicarbonate and 30% sodium chloride replacement), and B4 (0.5% sodium bicarbonate and 45% sodium chloride replacement). The results showed that sodium replacement up to 45% had no impact on texture (as represented by Allo-Kramer shear values) and water activity. After cooking, Group B1 exhibited the highest L* value (72.1) and the lowest b* (6.6) when compared to other groups. In conclusion, replacing sodium chloride with potassium chloride up to 45% in the presence of sodium bicarbonate did not affect negatively several quality traits (sensory traits, composition, and texture, etc.).

Resumo em Inglês:

ABSTRACT The apparent faecal digestibility of the essential amino acids from Ω3 PUFA layer diets and feeding solutions to avoid possible adverse effects of such diets were investigated in two experiments conducted on Lohmann Brown laying hens. Experiment 1 used 72 layers assigned to three groups (C1, E1-1, E2), while experiment 2 used 96 layers assigned to four groups (C2, E1-2, E3, E4). All experimental diets have been enriched in Ω 3 PUFA by supplementing a conventional diet (C1, C2) with 5% flaxseed meal and 2% camelina meal. Diets E2 and E4 had an increased level of Cu (150 mg/kg), diets E3 and E4 were supplemented with 0.0125% enzyme mix, while diets E1-1 and E1-2 were only supplemented with 5% flaxseed meal and 2% camelina meal. The digestibility coefficients of the studied essential amino acids (threonine, valine, phenylalanine, isoleucine, leucine, lysine, cystine, methionine) were lower (p≤0.05) in groups E1-1 and E2 from experiment 1, than in the control group (C1). In experiment 2, the supplemental enzyme mix (E3) increased (p≤0.05) the digestibility coefficients of phenylalanine, lysine, cystine and methionine, compared to the diet with camelina and flaxseed meals (E1-2). The simultaneous inclusion of copper and enzyme mix in the E4 diet increased (p≤0.05) lysine digestibility compared to group E1-2 and sulphur amino acids digestibility, compared to the other groups (C2, E1-2 and E3). In both experiments, only the feed conversion ratio was different (p≤0.05) in favour of the control groups (C1 and C2), compared to the other groups.

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ABSTRACT The meta-analysis data were obtained from a survey of published articles over 15 years. The data were selected to classify the factors that impact broiler production and separated by influence aspects of animal production (thermal environment and other factors). The relevant data for each study were systematized, grouped and later tabulated and inserted into a database prepared in a spreadsheet. The variables used to analyze the thermal environment were temperature (comfort, high and low) and performance data (weight gain, feed intake, and feed conversion). The variables used for other features were ventilation (TER = tunnel + evaporative cooling, PP = positive pressure, NV = natural ventilation) and performance (feed conversion, live weight, mortality, and weight gain). The factors that may influence the production of broilers were tested by covariance analysis, Pearson correlation coefficient and divergence analysis, about the Cobb®, Ross® and Hubbard® strains. The results showed that the factors that most influenced the performance of broilers were temperature, ventilation rate, and genetic strain.

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ABSTRACT Myostatin (MSTN) is a negative regulator of skeletal muscle growth. In order to investigate whether there is a correlation between MSTN polymorphisms and chicken production performance, in this study, single nucleotide polymorphisms (SNPs) in MSTN gene were examined across 180 Daheng broilers by direct sequencing of PCR product, and the correlations between the genotype and body weight at the age of 1-10 weeks and carcass traits at the age of 73 day were analyzed. Five SNPs (rs313622770, rs313744840, rs316247861, rs314431084, rs317126751) of MSTN gene were identified across Daheng broiler samples, and four haplotypes were reconstructed based on the five SNPs. Results of association analysis showed that four (rs313622770, rs313744840, rs316247861 and rs317126751) of these SNPs had significant association with some growth traits (p<0.05), but there were no significant effect on carcass traits and the four SNPs were strong linkage. For rs314431084, there was no significant correlation between different genotypes and growth or carcass traits. The AA genotype of rs313622770, GG genotype of rs313744840, CC genotype of rs316247861, TT genotype of rs317126751 were good for chicken growth. Diplotypes were significantly associated with chest muscle and leg muscle weight (p<0.05). Overall, these results provide evidence that polymorphisms in MSTN gene are associated with growth traits in chicken. The SNPs in MSTN gene could be utilized as potential markers for marker-assisted selection (MAS) during chicken breeding.

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ABSTRACT Hawthorn has been traditionally used to improve blood circulation and medicating cardiac disorders as well as blood stasis and elimination of pulmonary hypertension. An experiment was conducted to evaluate the effect of different levels of hawthorn extract in the drinking water on cardiac indicators, serum antioxidant activity, growth and immunity of pulmonary hypertensive broilers reared at high altitude and prone to ascites. A total of 225 one-day-old unsexed broiler chicks (Ross308) were randomly assigned to 15 floor pens. A basal corn-soy based diet was formulated for all treatments. The treatments consisted of the addition of 0, 0.1, or 0.2 mL of hawthorn extract per liter of drinking water. Both levels of hawthorn flavonoid extract significantly (p<0.05) improved feed intake, body weight gain and FCR, and significantly (p<0.05) reduced abdominal fat, liver, and heart relative weights, as well as the number of birds affected with PHS compared with the controls. RV and TV were significantly (p<0.05) lower in hawthorn flavonoid extract fed birds than the controls in addition of significantly (p<0.05) lower TBARS but higher NO serum levels. In conclusion, hawthorn flavonoid extract may effectively be used as an herbal medicine to prevent pulmonary hypertension and cardiac disorders in chickens.

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ABSTRACT This study aimed at evaluating the effects of the physicochemical and nutritional characteristics of a biological silage meal made of tambaqui waste on dietary nutrient apparent digestibility and energy metabolism of commercial layer diets. Seventy-two 61-week-old Hisex White hens were assigned according to a completely randomized experimental design in two treatments: control diet and diet with 5% tambaqui waste biological silage meal (TWBSM), with six replicates of six birds each. The ensiled biomass presented grey brown color, acid aroma, viscous texture, 5.27±0.016pH, 96.28% dry matter (DM), 33.29% crude protein (CP), 33.65% ether extract (EE), 14.37% ashes, 13.63% non-nitrogen extract (NNE), 65.16 g.kg-1 calcium (Ca), 22.90 g.kg-1 phosphorus (P), and 5,666.07 kcal.kg-1 gross energy (GE). Higher (p>0.05) coefficients of apparent digestibility of DM, crude fiber, EE, and ash, and higher coefficient of GE metabolizability were obtained in the diet with 5% TWBSM. Due to its high CP content (33.29% on DM basis), TWBSM may be considered a protein feedstuff. Although no differences in CP digestibility (p>0.05) were detected, TWBSM presented high CP digestibility than the control diet due to proteins hydrolysis as a result of lactic fermentation by microorganisms during the ensilage process, yielding autolysed proteins of high biological value. Our results indicate that the biological silage meal produced from the residual biomass of tambaqui can be included up to 5% in commercial layer diets as it has good nutrient digestibility, and therefore, may potentially be used as a dietary energy and protein source.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the inclusion of cell wall of Saccharomyces cerevisiae (CWSc) and piperine in broiler rations and their effects on performance, carcass traits, blood parameters, ileal microbiota and nutrient digestibility. A randomized block design with five treatments and six replicates of 10 birds was used, totaling 300 chickens. The treatments consisted of: control ration (CR); CR + avilamycin (10 mg / kg); CR + CWSc (2.0 g / kg); CR + piperine (60 mg / kg); and CR + CWSc (2.0 g / kg) + piperine (60 mg / kg). The use of isolated piperine resulted in greater weight gain from 9 to 40 days of age (2505g). The additives CWSc and piperine conjugates influenced the lower coliform count in the ceca (4.45 CFU / g) and caused significant alterations in the biochemical serum and hepatic renal profile. The treatments had no effect on the nutrient metabolizable coefficients or on the carcass traits. There was no positive synergistic effect of the combined use of CWSc and piperine on broiler performance. The cell wall of Saccharomyces cerevisiae and piperine are effective at guaranteeing productivity, intestinal microbiota dynamics and hematological parameters; and as zootechnical additives, especially in broiler feeds free of antimicrobial performance enhancers.

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ABSTRACT Chicken infectious anemia (CIA) is an immune-suppressive disease caused by chicken anemia virus (CAV). It is characterized by lymphoid atrophy, aplastic anemia, especially in chicks. In this study, full-length genomic characterization of CAV DNA from the broiler flocks in Turkey and phylogenetic analysis were aimed. In the study, CAV DNA were found positive for 37 (53%) flocks with PCR studies from thymus tissues of each 70 broiler flocks. And 17 purified CAV DNA PCR products from these 37 CAV isolates were full length sequenced with the NGS method (Illumina MiSeq). Also with the phylogenetic analyses, full length PCR products of 17 purified CAV isolates have been determined as 2298bp genome size and 99% similarity with each other. The highest similarity (99%) has been detected with the isolates from China and Taiwan. Furthermore, a 97-98% similarity has been detected with vaccine strains (Cux-1, 26P4 and Del Ros) and also 88-90 % similarity has been detected with GyV4 and GyV3 isolates. As a result, in the study full length genomic characterization of CAV DNA from the 7 regions of Turkey were determined. And also all Turkish CAV isolates and vaccine strains were in group 2 according to the phylogenetic tree were obtained. But these isolates and vaccine strains were not found in the same group with GyV3 and GyV4 strains. Besides, these CAV isolates were showed more similarity to the isolates reported from Taiwan and China than the vaccine strains.

Resumo em Inglês:

ABSTRACT The present study was carried out in the poultry sector of UNOESC Xanxerê to evaluate the effect of various inclusion levels of seaweed (Schizotrichium ssp.) in the diet of broiler chickens in terms of performance, carcass yield, organ profiles and fatty acids levels in meat. We studied 480 one-day-old Cobb chicks, distributed in a completely randomized experimental design, with four treatments and six replicates containing 20 birds each, totaling 24 experimental units. At 7, 21 and 35 days of age, the birds were weighed for performance evaluation (live weight, weight gain, feed intake, feed conversion and mortality). At 35 days of age, one chicken per experimental unit was sacrificed for evaluation of carcass yield and its parts, together with isolation of the left thigh for analysis of the fatty acid profile. The inclusion of seaweed in the diet did not alter the characteristics of performance or yield in carcass and organs; however, the supplement changed the profile of fatty acids of the meat, enriching the omega-3 series, primarily DHA. We conclude that marine algae of the genus Schizotrichium can be added to rations without compromising the development of the birds to improve the profile of fatty acids in the meat.

Resumo em Inglês:

ABSTRACT High environmental temperature is limiting factor in broiler production. In order to minimize the undesirable consequences of acute or chronic heat stress, the techniques of fixed dietary electrolyte balance and early heat conditioning were evaluated. The objective of this study was to evaluate the possible interactions and effects of dietary electrolyte balance and early heat conditioning on feed intake, body weight, feed conversion ratio, mortality, energy bioeconomic index, fecal moisture, abdominal fat, and breast meat color (L*a*b*) of broilers submitted to chronic or acute heat stress. In total, 1280 chicks, were equally divided in experiment I (chronic heat stress, 6h/day at 32ºC from 35 to 39 d of age) and II (acute heat stress, 36 ºC for 6h at 38 days of age). The data of both experiments were combined and analyzed according to a 2x2x2 factorial arrangement (early heat conditioning (ETC) or not; fixed dietary electrolyte balance (EB) or not; and exposure to acute or chronic heat stress). ETC consisted of exposing 5-d-old birds to 36.0 °C for 24 hours. No interaction among the evaluated factors was detected. Birds exposed to acute heat stress presented significantly higher compared with chronic heat stress. Fixed dietary EB resulted in significantly higher fecal moisture. Lower abdominal fat percentage was obtained in birds exposed to chronic relative to acute heat stress. Higher breast meat L* and b* values were observed in birds exposed to acute heat stress than those submitted to chronic heat stress, indicating worse meat quality.

Resumo em Inglês:

ABSTRACT Avian cellulitis causes significant losses to the poultry industry. Avian-pathogenic Escherichia coli (APEC) is the etiological agent of that disease. This microorganism has zoonotic potential and may act as reservoir of antimicrobial-resistance genes. In this context, the production of extended-spectrum B-lactamase (ESBL) is one of the main antimicrobial resistance mechanisms. The objective of this study was to determine the production of ESBL in an Escherichia coli (E. coli) strain isolated from avian cellulitis lesions. Twenty-two E. Coli isolates were harvested from cellulitis lesions in chicken carcasses in a commercial processing plant. Isolates were then submitted to virulence genotypic profile (iutA, hlyF, iss, ironN, ompT) analysis, antimicrobial susceptibility test, and detection of ESBL production. The results showed that 22.7% of the isolates presented five virulence genes, 9.1% four genes, 36.4% three genes, 13.6% two genes, and 18.2% one gene. The tested isolates showed resistance to ampicillin (90.9%), ceftiofur (54.5%), gentamicin (45.5%), tetracycline (72.1%), sulfamethoxazole/trimethoprim (54.5%), and enrofloxacin (54.5%). Furthermore, 77.3% of the isolates presented multidrug resistance (MDR) profile and 72.7% were positive for ESBL production. This study is the first description of ESBL-producing APEC isolated from avian cellulitis lesions, which suggests the need to establish efficient APEC control measures and programs to prevent flock productivity losses due to colibacillosis and public health risks.

Resumo em Inglês:

ABSTRACT The objectives of this study were to determine the most suitable probe diameter and egg position to perform the eggshell breaking strength test using a texturometer, as well as the most reliable parameter to estimate eggshell quality when no electronic devices are available. Eggshell quality (eggshell breaking strength, eggshell weight, eggshell percentage, eggshell thickness, shell weight per unit surface area) was evaluated as a function of texturometer probe diameter (2, 10, and 75mm), egg type (white and brown) and egg position (horizontal and vertical). In the experiment, 2520 eggs from 60-week-old commercial layers were separated by specific gravity measured by flotation method in saline solution (1.070 to 1.100 g/cm3 with intervals of 0.005 g/cm3).Data were submitted to analysis of variance in a completely randomized design, and means were compared by Tukey’s test (p<0.05). Correlations between characteristics were calculated using the Pearson’s method. The results showed that the most suitable probe diameter for the analysis of eggshell breaking strength was 75 mm, independently of egg positioning or type egg. White eggs should be positioned vertically in relation to the probe, whereas brown can be placed in any position. When it is not possible to evaluate eggshell quality using electronic devices, the measurement of shell weight per unit surface area is recommended.

Resumo em Inglês:

ABSTRACT Tibial dyschondroplasia (TD) is a skeletal disorder that occurs in the proximal metaphyses of tibiotarsus and sometimes tarsometatarsus, resulting in the development of avascularized and non-mineralized abnormal cartilage and causing significant economic loss. In this study, we aimed to show the histopathological changes and the relationship between the release of Heat-Shock Protein 27 (HSP-27) and oxidative DNA damage in broiler chickens with tibial dyschondroplasia, using histopathologic and immunohistochemical methods. Our study material consisted of totally 20 animals out of 42 days old 205 Ross 308 broiler chickens, 10 with TD lesions and 10 healthy control subjects. Tissue samples taken from animals performed necropsy was exposed to routine tissue follow-up. Macroscopically, unilateral and bilateral thickening and swelling were observed in the growth plates of tibiotarsal joints of the broiler chickens diagnosed with tibial dyscondroplasia. Histopathologic examination of the tibiotarsal joints of broiler chickens affected by TD revealed an increase in the number of immature chondrocytes, as well as deficiencies in vascularization and calcification. In the immunohistochemical study; HSP-27 and 8-OHDG release was positive in the chondrocytes located on the Proliferative Zone, Maturation Zone and Hypertrophic Zone. However, the positivity was the most profound in the PZ and MZ, while less in the HZ chondrocytes. As a result; we demonstrated by immunohistochemical methods that the increase in the HSP-27 release is parallel to the increase in 8-OHDG release in TD lesioned areas and this may be related to oxidative stress.