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White striping (WS) is a myopathy characterized by the appearance of white stripes parallel to the muscle fibers in the breast of broiler chickens, composed of adipose and connective tissues. This condition causes economic losses and, although common, its etiology remains poorly understood. Hence, the objective was to identify genes and biological mechanisms involved in the early stages of WS using a paternal broiler line that grows slightly slower than commercial ones, at 35 days of age, through the RNA sequencing of the pectoralis major muscle. Thirty genes were differentially expressed between normal and WS-affected chickens, with 23 upregulated and 7 downregulated in the affected broilers. Of these, 14 genes are novel candidates for WS and are implicated in biological processes related to muscle development ( CEPBD , DUSP8 , METTL21EP , NELL2 , and UBE3D ), lipid metabolism ( PDK4 , DDIT4 , FKBP5 , DGAT2 , LIPG , TDH , and RGCC ), and collagen ( COL4A5 and COL4A6 ). Genes related to changes in muscle fiber type and the processes of apoptosis, autophagy, proliferation, and differentiation are possibly involved with the initial stage of WS development. In contrast, the genes linked to lipid metabolism and collagen may have their expression altered due to the progression of the myopathy.

Ca and P homeostasis across the egg-laying cycle is a complex process involving absorption in the small intestine, reabsorption/excretion in the kidneys, and eggshell gland secretion. Diets with inadequate calcium and phosphorus can interfere with their absorption and digestibility, resulting in eggshell quality losses and reduced productive life, affecting egg production and welfare. A better understanding of gene expression profiles in the kidneys of laying hens during the late egg-laying period could clarify the renal role in mineral metabolism at this late stage. Therefore, the performance, egg quality and bone integrity-related traits, and expression profiles of kidney candidate genes were evaluated in 73-week-old laying hens receiving different Ca and P ratios in their diet: a high Ca/P ratio (HR, 22.43), a low ratio (LR, 6.71), and a medium ratio (MR, 11.43). The laying hens receiving the HR diet had improved egg production and eggshell quality traits compared to the other two groups. Humerus length was shorter in the HR than in the other groups. The CYP24A1 and TRPC3 genes were differentially expressed ( p.adj ≤ 0.05) among the groups. Therefore, their expression profiles could be involved in calcium and phosphate transcellular transport in 73-week-old laying hens as a way to keep mineral absorption at adequate levels.

Industrial egg residue (IER) possesses substantial concentrations of calcium and crude protein. The objective of this study was to measure the digestibility and performance of broilers when IER was added to the feed. Four treatments were tested, which caused increasing replacement of calcitic limestone by IER (0, 35, 70 and 100%) during a 42-day production cycle. First, total bird excreta were collected from broilers with and without IER, and we determined dry matter digestibility, apparent metabolizable energy (AME), calcium, and nitrogen retention. The IER presented 7.5% of crude protein, 31% of calcium, 209 kcal/kg of AME and the digestibility coefficients for dry matter, crude protein, and calcium were calculated at 83.95%, 86.20%, and 67%, respectively. After the digestibility test, the effects of IER on performance, carcass and meat yield were evaluated. No significant differences between the treatments were found in terms of performance (weight gain, feed conversion, consumption, and mortality), and no differences were found in terms of carcass or meat yield. A linear decrease in the percentage of abdominal fat was observed with increasing inclusion of IER in feed. These findings suggest that IER can totally replace limestone (calcium carbonate) in broiler diets.

The objective of this study was to evaluate the chemical composition and fatty acid profile of broilers fed diets containing glycerol monolaurate (GML) in place of antimicrobials. Groups: T0 group used as control; T100, T200, and T300 groups received diets supplemented with 100, 200, and 300 mg/kg of GML, respectively. The feed mixture used in the poultry feed during the four phases of the production cycle (days 1 to 7; 8 to 21; 22 to 35; and 36 to 42 of birds age) showed similar levels of protein, lipid and ash, as well as fatty acid profiles. Samples of frozen breasts from chickens slaughtered at 42 days of age were used for chemical gross composition and fatty acid analysis. We observed lower lipid levels in the meat of broilers in the T200 and T300 groups than in the T0 group. Lower lipid peroxidation occurred in the meat of animals that consumed GML in respect to control. Total saturated fatty acid percentage was lower, while total polyunsaturated fatty acid percentage was higher in the meat of broilers fed GML than in the control group. We conclude that the increase in GML concentrations alters the lipid profile of broiler meat., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The feed restriction of pigs aims to improve the nutrient utilization of the diet, reduce carcass fat and increase lean meat. Immunocastration is a painless, reversible technique that improves animal welfare, decreases boar taint in meat, leading to lower fat deposition and increases lean meat. This study aimed at evaluating either feeding (restricted) programs (FP) and castration categories (surgically castrated × immunocastration) in terms of pig performance, carcass traits and meat quality. Castration category and FP did not influence marbling, initial pH and drip loss in loin and ham. However, immunocastrated pigs presented lighter loins and hams with lower ultimate pH, compared to the surgically castrated pigs. The FP with lower feed volume resulted in higher ultimate pH. Immunocastrated males had a higher live weight than those surgically castrated. Also, the more the feed supply decreased, the better the feed conversion. Immunocastrates had lower carcass yields, however these pigs had their backfat thickness decreased and lean meat increased in the carcass, without affecting the loin depth., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The effect of different group sizes of pigs (3, 5, and 10 pigs) during handling on physiological parameters, carcasses, and pork quality traits at the farm and slaughterhouse were evaluated in 360 pigs from five farms (four repetitions or group/treatment/farms). Data was analyzed as a factorial of 3 × 5 (3 treatments × 5 farms) to check effects of treatments by analysis of variance in ANOVA. Ease of handling decreased as the group size increased. However, time taken in handling was not influenced by the group size ( p > 0.10). Moving pigs in groups of five animals reduced effects on blood cortisol levels ( p < 0.05). Fighting and handling lesions in the carcasses increased for bigger handling groups ( p < 0.05). Pigs handled in groups of three and ten animals had a higher pHu and initial temperature in Longissimus thoracis and Semimembranosus ( p < 0.05) and lower drip loss in Semimembranosus ( p < 0.05). However, meat quality classifications of the carcasses were not affected by treatments. Based on the results, moving groups of five pigs seems to be the best strategy to improve animal welfare, carcasses and pork quality.

The objective of this study was to determine whether supplementing the diets of laying hens with selenomethionine (SM, 1% selenium) improves performance and egg quality. We supplemented diets with SM as follows: T0 control (without SM); T5, T10, T15, and T20 were supplemented with 5, 10, 15, and 20 mg of SM/kg of feed, respectively (equal to 0.05, 0.10, 0.15, and 0.20 mg selenium/kg of feed). T5 and T10 hens showed better feed conversion per kg of egg, percentage of laying, higher daily feed intake, and higher average egg weight. The eggs of hens supplemented with SM had lower levels of lipoperoxidation (LPO) in fresh (T15 and T20) and stored eggs (T20). Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities, as well as total antioxidant capacity were greater in egg yolks after storage (T10; T15; T20 compared to T0). Hens supplemented with SM had elevated GPx and SOD activities and decreased oxidative reactions. PRACTICAL APPLICATIONS: Selenium has several nutraceutical properties, with beneficial effects on the health of the animal and the food produced from them (eggs, in this case). Selenomethionine supplementation in the diet of laying hens improves productive efficiency, stimulates the antioxidant system and reduces lipid peroxidation in the egg yolk. Egg-laying hens that received selenomethionine showed minimized lipid peroxidation in stored eggs, possibly improving shelf life of the eggs., (© 2019 Wiley Periodicals, Inc.)

The aim of this study was to investigate whether microalgae in Japanese quail feed alters performance, fatty acid profiles in the eggs and egg quality. One hundred quails were distributed in four groups and five replicates of five birds per experimental group. The treatments consisted of four levels of Spirulina platensis microalgae (0%, 5%, 10%, and 15%) in the diets. We evaluated the productive performance and chemical-physical characteristics of eggs, the oxidant/antioxidant status in egg yolks, and the fatty acid profile in the diet and egg yolks. Microalgae in the diet did not influence egg production; however, it increased the yolk index as well as the color intensity of the yolk. Saturated and polyunsaturated fatty acid levels decreased in egg yolks, and monounsaturated fatty acid levels increased in the yolks. Lipid peroxidation levels were lower and total antioxidant capacity was higher in egg yolks of quails receiving microalgae in the diet. PRACTICAL APPLICATIONS: Microalgae in quail diets improves egg quality and provides benefits to consumer health, acting as an antioxidant and immune-stimulant. Microalgae in quail diets had positive effects on egg quality. This is because it reduced levels of saturated fatty acids that are undesirable, and increased monounsaturated fatty acid levels that are beneficial to the health of consumers. Finally, antioxidants increased in egg yolks, consequently reducing lipid peroxidation., (© 2019 Wiley Periodicals, Inc.)

1. This work investigates the apparent metabolisable energy (AME), its nitrogen-corrected form (AMEn) and amino acid (AA) digestibility coefficients of the microalgae Spirulina platensis as an ingredient in broiler chicken diets. 2. One group of birds was fed with a basal control diet (BD), and another was fed with a test diet composed of the BD with the addition of the microalgae at a proportion of 200 g/kg. AME and AMEn were assessed by total excreta collection and indigestibility analysis using acid-insoluble ash (AIA) as a marker. 3. The microalgae comprised 888.0 g/kg dry matter (DM), 18.42 MJ/kg gross energy, 514.7 g/kg crude protein, 9.9 g/kg ether extract, 10.6 g/kg crude fibre, 94.4 g/kg ash, 3.1 g/kg Ca and 11.0 g/kg P. 4. The values obtained for AME (13.48 MJ/kg DM) and AMEn (11.72 MJ/kg DM) were higher (p < 0.01) than those obtained using the AIA method (9.39-8.29 MJ/kg DM). The microalgae ileal digestibility coefficients were 0.80 ± 0.04 and 0.78 ± 0.04 for essential and non-essential AA, respectively. 5. Overall, the metabolisable energy content and digestibility of AA for S. platensis indicated that the microalgae are potentially an alternative nutrient source for broilers. The AIA method underestimated AME and AMEn in comparison to the total excreta collection method.

Economic losses due to an increase of leg disorders in broilers have become a major concern of the poultry industry. Despite the efforts to reduce skeletal abnormalities in chickens, insufficient progress has been made. Bacterial chondronecrosis with osteomyelitis (BCO) is one of the main disorders that affect bone integrity in broilers. However, the genetic pathways and genes involved in most bone problems, including BCO, remains unclear. In this study, femoral samples from male broilers with 45 days of age affected or not with BCO were used to compare the relative expression with a reverse transcription real time PCR approach of 13 candidate genes: SPP1 (osteopontin), TNFRSF11B (osteoprotegerin), SPARC (osteonectin), CALB1 (calbidin 1), CALM (Calmodulin 2), IBSP (sialoprotein), COL1A2 (collagen, type I, α 2), BMP2 (bone morphogenetic protein 2), BMP3 (bone morphogenetic protein 3), RANKL (κ-B nuclear factor ligand), SMAD1 (SMAD family member 1), LEPR (leptin receptor) and RUNX2 (related transcription factor Runt 2). Differential expression test between affected and non-affected groups was performed using the REST software. The RUNX2 and SPARC genes were downregulated (P<0.05) in the affected group, with reduced expression of fourfold when compared with the non-affected group. This result indicates that the downregulation of RUNX2 and SPARC can contribute to an increased incidence of BCO in broilers.

Three experiments were carried out to estimate the optimal ratios of digestible phenylalanine + tyrosine (Phe + Tyr), histidine (His), and leucine (Leu) relative to digestible lysine (Lys) for performance and carcass criteria of Cobb-500 broilers from 8 to 17 d of age. In each experiment, 160 male chicks were allocated to a completely randomized experimental design with eight replicate pens, each receiving five dietary treatments. A common, semi-purified basal diet was formulated to meet all dietary recommendations except for those of the tested amino acids (i.e., Phe + Tyr, His, and Leu). Growth performance and carcass characteristics data were analyzed using various requirement-estimation models, including 95% of the quadratic regression, linear response plateau (LRP; i.e., stepwise regression), LRP-to-quadratic regression ratio; and quadratic broken line (QBL). Graded digestible Phe + Tyr ratios elicited a quadratic response (P < 0.05) in body weight gain and linear responses (P < 0.05) in breast and breast fillet weights. Linear effects (P < 0.05) were also observed when graded ratios of digestible His were fed for feed intake and weight gain, and quadratic responses (P < 0.05) were noted for feed conversion ratio and breast and breast fillet weights and yields. Graded Leu ratios elicited quadratic responses (P < 0.05) in feed intake, weight gain, and breast and breast fillet weight and yield. Based on growth and carcass parameters, the estimated ideal digestible ratios of Phe + Tyr, His, and Leu relative to digestible Lys were 112, 38, and 104%, respectively, for broiler chicks raised from 8 to 17 d of age., (© The Author 2016. Published by Oxford University Press on behalf of Poultry Science Association.)

A QuEChERS method of ractopamine (RCT) residue detection in swine meat and bone meal (MBM) samples was demonstrated. Samples were hydrolyzed with protease and β-glucuronidase prior to QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction and clean-up. Samples were analyzed in a Liquid Chromatography (equipped with ACE 5 C18 column under gradient elution) coupled with a triple quadrupole mass spectrometer operating in positive electrospray ionization mode (using multiple reaction monitoring, MRM). The method was validated for its specificity, decision limit (CCα), detection capability (CCβ), recovery, repeatability, reproducibility, linearity, limits of detection (LODs), quantification (LOQs), and stability according to international guidelines (European Commission Decision 2002/657/EC). Recoveries ranged from 96.3 to 107.0%. Repeatability and reproducibility showed both RSD<5.7% and 3.1%, respectively. LODs and LOQs were 1.91 and 6.36 ppb, respectively. CCα and CCβ values were 1.91 and 2.37 ppb, respectively. RCT showed good stability for spiked samples and real samples when the concentration was higher, otherwise at lower concentration stability was lower. The proposed method can be successfully applied on a regular basis for the determination of RCT in MBM, demonstrating the usefulness of the method as a tool for compliance monitoring in regulatory laboratories., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Two independent experiments were conducted with male Cobb × Cobb 500 broilers to determine the optimal valine-to-digestible-lysine ratio for broiler development. We conducted a randomized block experiment with 7 treatments, each with 8 replicates of 25 starter birds (8 to 21 d of age) and 20 finisher (30 to 43 d of age) birds. To prevent any excess of digestible lysine, 93% of the recommended level of digestible lysine was used to evaluate the valine-to-lysine ratio. The utilized levels of dietary digestible lysine were 10.7 and 9.40 g/kg for the starting and growing phases, respectively. A control diet with 100% of the recommended level of lysine and an adequate valine-to-lysine ratio was also used. The feed intake, weight gain, feed conversion ratio, and carcass parameters were evaluated. The treatments had no significant effect on the feed intakes or carcass parameters in the starter and finisher phases. However, during both of the studied phases, we observed a quadratic effect on weight gain and the feed conversion ratio. The broilers of both phases that were fed test diets with the lower valine-to-lysine (Val/Lys) ratio had poorer performance compared with those broilers fed control diets. However, when higher Val/Lys ratios were used for the starting and growing broilers that were fed test diets, the 2 groups had similar performance. During the starting phase, in broilers that were fed a higher Val/Lys ratio, weight gain, and the feed conversion ratio improved by 5.5% compared with broilers fed the basal diets. The broilers in the growing phase also had improved performance (by 7 to 8%) when the test diets had higher Val/Lys ratios. Based on the analysis of the starter phase data, we concluded that the optimal digestible Val/Lys ratio for Cobb × Cobb 500 broilers is 77%, whereas for birds in the finisher phase (30 to 43 d of age), a digestible Val/Lys ratio of 76% is suggested.

Fish larvae of 'corvinas' (Pachyurus bonariensis and Plagioscion ternetzi) from Sinhá Mariana Lagoon, Mato Grosso State, were collected from March 2000 to March 2004, in order to determine the parasitic fauna of fishes. Larvae from the two species were parasitized by the same endoparasites: Contracaecum sp. Type 2 (larvae) (Nematoda: Anisakidae) in the mesentery and Neoechinorhynchus (Neoechinorhynchus) paraguayensis (Acanthocephala: Neoechinorhynchidae) in the stomach and the terminal portion of the intestine. Statistical analysis showed that there was a significant positive correlation between the standard length of hosts and the abundance of acanthocephalans and nematodes, and that the prevalence of nematodes presented a significant positive correlation with the standard length of the two species of hosts, indicating the presence of a cumulative process of infection. The present study constitutes the first record of nematodes and acanthocephalans parasitizing larval fish, as well as the first record of endoparasites in fish larvae in Brazil. In addition, it lists a new locality and two species of hosts for Contracaecum sp. Type 2 (larva) and N. (N.) paraguayensis.