Evaluation of a dacitic (rhyolitic) tuff breccia use on performance, inflammatory, and antioxidant responses in broilers mildly challenged with Eimeria spp.

The objective of the study was to investigate the effects of a dacitic tuff breccia (DTB) on Eimeria-infected broilers. A total of 600 one-day-old Cobb 500 male chickens were randomly assigned to 5 treatments with 10 replicates of 12 birds. Treatments were: an unchallenged control (UC), a challenged (CC) control (0% DTB), and 3 challenged groups with 0.125, 0.25, or 0.5% DTB. At d 14, birds in the CC and DTB groups were orally gavaged with mixed Eimeria spp., while the UC received water. Growth performance was evaluated during prechallenge, challenge, and postchallenge periods (0-14 d; 14-20 d; and 20-26 d, respectively). Gastrointestinal permeability was measured at 5 days postinfection (dpi). Intestinal histology and nutrient digestibility of dry matter (DM), crude protein (CP), and ileal digestible energy (IDE) were measured at 6 dpi. Liver activity of glutathione peroxidase (GSH-Px) was determined at 6 dpi, and concentrations of reduced (GSH) and oxidized glutathione (GSSG) were analyzed at 6 and 12 dpi. Data were analyzed using a linear mixed model analysis and Tukey's test (P ≤ 0.05). From 0 to 14 d, similar average daily gain (ADG) and average daily feed intake (ADFI, P > 0.05) were observed. Gain:feed ratio (GF) was higher in 0.125, 0.25, and 0.5% of DTB than the CC and UC (P < 0.001). From 14 to 20 d, the UC had the highest ADG, ADFI, and GF (P < 0.001). At 5 dpi, intestinal permeability was higher in the challenged groups than the UC. Additionally, the UC showed the highest apparent ileal digestibility of CP, whereas 0.125% DTB had higher CP digestibility than the CC and 0.5% DTB (P < 0.001). At 6 dpi, 0.125% DTB increased GSH-Px activity compared to the CC, 0.5% DTB, and UC (P < 0.001). At 12 dpi, 0.125% DTB showed increased GSH concentration compared to the CC, 0.25% DTB, and 0.5% DTB (P < 0.01). The mild coccidia infection negatively impacted growth performance, apparent ileal nutrient digestibility, intestinal histology, and gastrointestinal integrity in broilers. The use of 0.125% DTB exhibited potential in improving antioxidant responses, apparent ileal digestibility of CP, and growth performance.

Influence of dietary dacitic tuff breccia on laying hen performance and egg quality parameters and bone structure at 85 weeks of age after a non-anorexic molt program at 73 to 77 weeks.

The objective of the study was to assess the efficacy of AZOMITE (AZM), a dacitic tuff breccia, in laying hens through egg quality and production parameters. A total of ninety six 73-wk-old Hy-Line W-36 commercial laying hens were randomly assigned to 2 dietary treatments, a control diet and the same diet containing 0.25% AZM, with 24 replicates of 2 hens/replication. From 73 to 77 wk, hens went through nonanorexic molt, and, from 77 to 85 wk, the hens were evaluated for egg production, eggshell quality, and bone health. At wk 85, tibiotarsi were collected for ash and mineral composition, ileal contents were collected for calcium, phosphorus, apparent metabolizable energy corrected for N (AMEn), and apparent nitrogen retention (ANR) evaluation. AZM-fed hens tended to have higher body weight (P = 0.07) from 82 to 83 and 84 to 85 wk, and higher hen day egg production than control (90.54 vs. 79.51%, P = 0.005) from 84 to 85 wk. In general, no differences were reported in feed intake, eggshell color, egg weight, albumen height, Haugh units, or eggshell thickness (P > 0.05). However, shell strength and elasticity were improved (P < 0.02) and yolk color was decreased (P = 0.03) in AZM-fed hens than control. Moreover, the digestibility of Ca, AMEn, and ANR was increased with 0.25% AZM compared to control (P < 0.01). Tibiotarsi P and Ca percentage were lower in AZM-fed birds than control (P < 0.01), without affecting bone strength and mineral density (P > 0.36). Therefore, the use of 0.25% AZM showed a potential in improving egg production and eggshell strength, while maintaining bone quality in post-molt laying hens.

Effect of egg storage duration and egg turning during storage on egg quality and hatching of broiler hatching eggs.

In commercial hatcheries, it is common to store eggs before incubation. One practice to improve hatchability consists in egg turning during this storage. This work aims to highlight the effects of turning on the physicochemical aspects of eggs and, consequently, how this turning can influence the hatching of chicks. An experiment was conducted to evaluate the effects of storage duration and egg turning during storage on egg quality, hatchability, and residual analysis. A total of 7 500 hatching eggs were collected from a 55-week-old commercial Cobb500 breeder flock and storage according to the treatments. The experiment was completely randomized in a 3×2 factorial design with three storage periods (4, 8, and 12 days) and egg turning (180° turn of eggs once a day) or no turning during storage, totaling six treatments. Regardless of turning, eggs stored for 4 days weighed more than turned eggs stored for 8 and 12 days, which were similar (P < 0.05). Non-turned eggs experienced an increase in relative shell weight with increased storage duration, and non-turned eggs stored for 4 and 8 days differed from non-turned eggs stored for 12 days (P < 0.05). Albumen pH of turned eggs stored for 4 and 8 days was lower than that of non-turned eggs stored for the same durations (P < 0.05). Albumen pH of turned eggs increased as storage duration increased (P < 0.05). Egg turning increased hatching by 2.02% over that of non-turning (P < 0.05). Eggs stored for 12 days, irrespective of turning, had higher late embryonic mortality (P < 0.05) compared to the other treatments. It was concluded that turning eggs during pre-incubation storage was adequate to improve hatchability of fertile eggs. Storing fertile eggs for 12 days is harmful to egg quality and increases embryo mortality even if eggs were turned.

The effect of total sulfur amino acid levels on growth performance and bone metabolism in pullets under heat stress.

A study was conducted to investigate the effects of total sulfur amino acid (TSAA) levels on performance and bone metabolism in pullets under heat stress (HS). Hy-Line W36 day-old pullets (n = 216) were randomly distributed in 3 dietary treatments (70, 85, and 100% of TSAA), with 6 replicates of 12 birds. The treatments were defined as percentages of the TSAA level recommendation (100, 85, and 70%), and 85 and 100% of TSAA were obtained by adding L-Methionine to the basal deficient diet (70% of TSAA). The birds were raised under HS (35°C/7 h/D) from 1 to 18 wk. At 6, 12, and 18 wk, growth performance was measured. At 12 and 18 wk, bone weight, ash, collagenous (ColP), and noncollagenous proteins (NColP), tissue volume (TV), bone mineral content (BMC), and mineral density from total, cortical, and trabecular bones were evaluated. The means were subjected to ANOVA and, when significant (P ≤ 0.05), were compared by Dunnett's test. Regression analyses were performed to evaluate trends of TSAA dose response. Overall, birds fed 70% of TSAA showed poor growth and feed efficiency compared with other groups. Additionally, in at least 1 phase, birds fed 70% of TSAA showed lower bone ash, NColP, total BMC, and TV and higher ColP than the other treatments, whereas the cortical and trabecular TV and BMC were lower than 100% of TSAA (P < 0.04). Quadratic effects of TSAA levels on body weight gain (BWG) were found, and the level for maximum BWG was 95% of the TSAA recommendation (P < 0.03, R2 > 0.83). In conclusion, the use of a TSAA-deficient diet resulted in poor performance and delayed bone development. Additionally, the use of 100% of TSAA led to better initial structural bone development than 85% of TSAA. Therefore, the TSAA level recommended by the primary breeder guideline was enough to support growth and bone quality under HS, suggesting that HS does not alter TSAA requirement in pullets.

The effects of total sulfur amino acids on the intestinal health status of broilers challenged with Eimeria spp.

This study evaluated the effects of total sulfur amino acid (TSAA) levels on the performance and intestinal health of broilers challenged with Eimeria spp. A total of 432 one-day-old off-sex Cobb 500 male chicks were randomly assigned to a 3 × 2 factorial arrangement (6 replicates/12 birds), with diets and Eimeria challenge as the main factors. The diets were as follows: 70% (no methionine [Met] supplementation), 85, and 100% TSAA, supplemented with L-Met. At day 14, the challenged birds (n = 216) were orally gavaged with a pool of Eimeria acervulina, Eimeria maxima, and Eimeria tenella sporulated oocysts, and the unchallenged birds (n = 216) received water. At 6 and 12 D post inoculation (dpi), performance and intestinal health were evaluated. The challenge, regardless of diets, significantly impaired the performance, intestinal villi height, villus-to-crypt ratio, and ileal digestibility of dry matter, energy, and crude protein (CP) and modulated the tight junction protein (TJP) expression throughout the experiment. Moreover, the superoxide dismutase activity was increased, whereas the reduced glutathione (GSH)-to-oxidized glutathione (GSSG) ratio was decreased by the challenge at 6 dpi. Regardless of the challenge, the 70% TSAA diet reduced the body weight and feed intake in all phases, whereas the ileal digestibility of CP was higher in birds fed with the 70% TSAA diet than in those fed with the 100% TSAA diet at 6 dpi. No major differences were observed among the diets with regard to the intestinal histomorphology and TJP expression, and birds fed with the 100% TSAA diet had the highest GSH concentration at 12 dpi. Few interactions were observed, and the Met supplementation counteracted the negative effects of the Eimeria challenge on GSH concentration when 85 and 100% of TSAA levels were reached. Overall, the Eimeria challenge had a negative impact on growth and intestinal health. Moreover, the supplementation of L-Met until either 85 or 100% of TSAA levels were reached was enough to assure good performance and intestinal health in birds challenged or not challenged with Eimeria spp.

The effect of total sulfur amino acid levels on growth performance, egg quality, and bone metabolism in laying hens subjected to high environmental temperature.

This study evaluated the effects of total sulfur amino acid (TSAA) levels on performance, egg quality, and bone metabolism in laying hens subjected or not to high environmental temperature (HT). HyLine W36 layers (n = 144) were randomly distributed in a 2 × 3 factorial arrangement. Room temperature (control, CR: 21°C/24 h; and high temperature, HR: 32°C/8 h) and diets (70, 85, or 100% of TSAA) were the main factors, with 4 replicates of 6 birds (19 to 45 wk). The TSAA levels were obtained by adding L-Methionine (L-Met) to the basal diet (70% of TSAA) until 85 and 100% of TSAA were reached. At weeks 21, 34, and 45, growth performance, egg production, and egg quality traits were evaluated. At 45 wk, bones were evaluated for collagenous and non-collagenous proteins, bone volume, mineral content, and mineral density from total, cortical, trabecular, and medullary portions. When interactions were found, the increase of TSAA levels (85 and 100%) was able to counteract the negative effects of HT. In general, HT reduced egg production (P < 0.05) and did not significantly affect bone quality. The birds fed 70% of TSAA showed higher feed conversion, lower body weight, egg weight, and egg mass than birds fed 85 and 100% of TSAA in at least one phase. The birds fed 100% of TSAA showed higher egg production and egg mass than the other treatments at 21 wk of age. The cortical and trabecular bone mineral densities were higher for birds fed 100 than 70% of TSAA, whereas the medullary bone mineral content and density were higher for birds fed 70 than 100% of TSAA. In conclusion, HT had negative impact on performance, egg quality and no effect on bone development. The supplementation of L-Met until either 85 or 100% of TSAA levels were reached was enough to assure good performance, egg quality, and bone development in laying hens subjected or not to HT.

L-Arginine supplementation enhances growth performance, lean muscle, and bone density but not fat in broiler chickens.

This study evaluated the effects of crystalline arginine (Arg) on performance and body composition in male broilers. A total of 600 1-day-old Ross 308 broilers were distributed in a completely randomized design, with 5 treatments and 6 replicates of 20 birds. The treatments were given as a percentage of the Ross 308 requirement, and defined as 70, 80, 90, 100 (Ross 308 requirement), and 110% of Arg. Body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were evaluated at 10, 24, and 42 d. Bone growth was measured from 7 to 11 d using mineral apposition rate (MAR) technique. At 42 d, 2 birds per pen were euthanized for bone mineral density (BMD) and body composition measurement using dual-energy X-ray absorptiometry, and liver gene expression and muscle diameter size analysis. The means were subjected to ANOVA and, when significant (P ≤ 0.05), were compared by Dunnett's test. Regression analyses were performed to evaluate trends of Arg dose response. Birds fed 70 and 80% of Arg had lower BWG than the ones fed 100% of Arg (P < 0.001), with quadratic effects for all phases (P < 0.001, R2 = 0.94). The 70% of Arg group showed lower FI compared to 100% from 11 to 24 d and 1 to 42 d (P < 0.009), with quadratic and linear effects (P < 0.049, R2 > 0.72), respectively. The 70% of Arg group showed higher FCR compared to 100% (P < 0.0001) with quadratic effects (P < 0.002, R2 > 0.94) for all periods. At 42 d, the 70% of Arg group showed lower BMD, tissue, and lean muscle percentage than 100% of Arg. There was a quadratic effect of Arg levels on lean muscle (P = 0.046, R2 = 0.89). Therefore, the dietary supplementation with Arg is necessary as it leads to an overall body growth with increased lean deposition and BMD, without increasing fat accretion in Ross 308 broiler chickens.

Comb, cloaca and feet scores and testis morphometry in male broiler breeders at two different ages / Escores de crista, cloaca e de pé e morfometria testicular em galos de matriz pesada em duas diferentes idades

In broiler breeder roosters, the weight of the testes is positively associated with daily sperm production and fertility. In birds, the testes are located in the coelomic cavity, not being accessible to reproductive evaluation as mammalian testes. The reproductive evaluation of roosters is based on phenotypic traits. Any changes on testes will be reflected on fertility levels. The aim of this paper was to evaluate the potential of association of phenotypic traits as body weight (BW), comb scores (COS), cloaca scores (CLS) and feet scores (FS) with testicular morphometric parameters in adult Cobb® Mx roosters in two ages (25 and 45 weeks of age). The low BW roosters had lower testes weight (TW), smaller seminiferous tubule diameter (STD) and lower comb and cloaca scores than the medium and high BW roosters (P≤0.05). Heavy roosters had the highest COS and bigger seminiferous epithelium height (SEH). There was no statistical difference between the BW categories in FS and volumetric proportion of seminiferous tubule (ST) and interstitial tissue (IT). Considering the age effect, roosters with 45 weeks of age had lower TW and ST than 25-week roosters. Positive, moderate and significant correlation was found between testes weight and phenotypic characteristics as BW, COS and CLS in 45week roosters. A positive, moderate and significant correlation was found between body weight and histologic testicular characteristics as STD and SHE in both evaluated ages. In conclusion, there is a regression in the testes weight with age and it is more intense in Cobb® Mx roosters with lower BW. Furthermore, it is concluded that the BW positively influences the testes weight and histological quality of the testes. COS and CLS can be used with moderate potential prediction to identify roosters with low testes weight at 45 weeks of age.(AU)

Em galos de matriz pesada sabe-se que o peso dos testículos pode ser associado positivamente com a produção diária de espermatozoides e que alterações nos testículos irão refletir na fertilidade. Nas aves, os testículos estão localizados dentro da cavidade celomática, e, portanto, não são acessíveis para exame andrológico direto, como em mamíferos. A avaliação reprodutiva de galos se baseia principalmente em características fenotípicas. Buscou-se avaliar o potencial de associação de alguns parâmetros fenotípicos, como peso corporal (PC), escores de crista (ECR), escores de cloaca (ECL) e escores de pés (EP), com parâmetros morfológicos de testículos em galos Cobb® Mx em duas idades (25 e 45 semanas de idade). Galos leves apresentaram menor peso testicular (PT), menor diâmetro de túbulo seminífero (DT), e menores ECR e ECL que galos médios e pesados (P≤0.05). Galos pesados apresentaram os maiores ECR e maiores valores para altura do epitélio seminífero (AE), e DT. Não houve diferença estatisticamente significativa entre as categorias de peso para escores de pé e proporções de túbulo seminífero (TS) e interstício (INT). Considerando-se o efeito da idade, galos com 45 semanas de idade apresentaram menores PT e TS que galos com 25 semanas de idade. Correlação positiva, moderada e significativa foi encontrada entre peso de testículo e características fenotípicas como ECR, ECL e PC em galos de 45 semanas de idade. Foi encontrada correlação positiva, moderada e significativa entre PC e características testiculares como DT e AE nas duas idades avaliadas. Conclui-se que em galos Cobb® Mx ocorre regressão do testículo com o avanço da idade, e ela é mais intensa em galos com menor peso corporal. Conclui-se que o PC tem influência positiva no peso e índices histomorfométricos dos testículos, e que escores de crista e de cloaca podem ser utilizados com potencial moderado de predição para identificar galos com baixo peso de testículos em galos com 45 semanas de idade.(AU)