Pequi Oil (Caryocar brasiliense Camb.) Attenuates the Adverse Effects of Cyclical Heat Stress and Modulates the Oxidative Stress-Related Genes in Broiler Chickens.

The present study was conducted to determine the possible antioxidant protection of pequi oil (PO) against cyclic heat stress in broiler chickens and to highlight the application of PO as a promising additive in broiler feed. A total of 400 one-day-old male broiler chicks (Cobb 500) were randomly assigned to 2 × 5 factorially arranged treatments: two temperature-controlled rooms (thermoneutral-TN or heat stress-HS for 8 h/day) and five dietary PO levels (0, 1.5, 3.0, 4.5, or 6.0 g/kg diet) for 42 days. Each treatment consisted of eight replicates of five birds. The results showed that HS increased glucose (p = 0.006), triglycerides (p < 0.001), and HDL (p = 0.042) at 21 days and reduced (p = 0.005) serum total cholesterol at 42 days. The results also showed that HS increased the contents of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In contrast, PO linearly decreased AST (p = 0.048) and ALT (p = 0.020) at 21 and 42 days, respectively. The heterophil-to-lymphocyte ratio in the birds under HS was higher than in those in the TN environment (p = 0.046). Heat stress decreased (p = 0.032) the relative weight of their livers at 21 days. The superoxide dismutase activity increased (p = 0.010) in the HS treatments in comparison to the TN treatments, while the glutathione peroxidase activity in the liver decreased (p < 0.001) at 42 days; however, the activity of catalase had no significant effects. Meanwhile, increasing the dietary PO levels linearly decreased plasma malondialdehyde (p < 0.001) in the birds in the HS environment. In addition, PO reduced (p = 0.027) the expression of Hsp 70 in the liver by 92% when compared to the TN treatment without PO, mainly at the 6.0 g/kg diet level. The expression of Nrf2 was upregulated by 37% (p = 0.049) in response to PO with the 6.0 g/kg diet compared to the HS treatment without PO. In conclusion, PO supplementation alleviated the adverse effects of HS on broilers due to its antioxidant action and modulation of the genes related to oxidative stress, providing insights into its application as a potential feed additive in broiler production.

Different dietary electrolyte balance values on performance, egg, and bone quality of Japanese quail (Coturnix Coturnix Japonica) under heat stress.

The objective of this study was to evaluate the productive performance and quality of eggs and bones of Japanese quails that received different dietary electrolyte balance (EB) and were submitted to thermoneutrality or heat stress conditions. Eight hundred Japanese quails of 21 days of age were selected and distributed randomly in two bioclimatic chambers: thermoneutral chamber (23 °C ± 2 °C) and heat-stress chamber (33 °C ± 2 °C). The treatments were in a 2 × 5 factorial arrangement, with two temperatures and five EB levels (165, 215, 265, 315, 365 mEq/kg) with four replicates of 20 birds each. The productive performance and egg quality (in 3 cycles of 21 days) were measured. At 105 days old, the bone quality was evaluated. Data were analyzed by Minitab, and the means were compared by Tukey's test and regression test for levels (P < 0.05). Quails submitted to thermoneutrality showed better performance and egg and bone quality. The highest production rate was the EB level of 265 mEq/kg. Low values of EB (165 and 215 mEq/kg) and high values (365) impaired egg quality, and the ideal was 315 mEq/kg. Lower levels of balance provided poor bone density. In conclusion, the results of this study indicated that heat stress impairs the production and quality of quail eggs and bones. Furthermore, by using intermediate EB levels (265 and 315) mEq/kg, it is possible to improve egg production and egg quality, and using high levels increases bone mineral density.

Analysis of metabolic pools in broilers chicks.

This paper shows the possibility of obtaining new parameters for the mathematical modelling of data on stable isotopes in biological systems and its application in obtaining data on metabolic pools of blood plasma, blood serum, liver and muscle of broilers. This theory states that the modelling of turnover used for studies of isotopic incorporation when the metabolism has a single metabolic pool is feasible by the technique of setting an exponential. However, when the metabolism has more than one metabolic pool, it is necessary to apply the linearization technique, linear regression adjustment and evaluation of the assumptions of regression to obtain the kinetic parameters such as half-life (T1/2) and isotope exchange rate (k). The application of this technique on carbon-13 data from 100 one-day-old chicks, with the change of diet composed of grains of the photosynthetic cycle of plants from C4 to C3, in broilers has enabled the discovery that the liver, blood plasma and blood serum have a single metabolic pool; however, the pectoral muscle has two metabolic pools. For the liver, blood plasma and blood serum, the half-life values were found by the exponential fit being T1/2 = 1.4 days with the rate of exchange of k = 0.502, T1/2 = 2.4 days with k = 0.293 and T1/2 = 2.0 days with k = 0.348, respectively. For the pectoral muscle, after linearization, the half-life values were found for T1/2(1) = 1.7 and T1/2(2) = 3 days, with exchange rates of k1 = 0.405 and k2 = 0.235, representing approximately 66 and 34%, respectively.

Nucleotídeos na dieta de frangos de corte e seus efeitos sobre taxa de turnover da mucosa intestinal antes e após lesões causadas por coccidiose / Nucleotides in broilers challenged diet and its effects on intestinal mucosa turnover rate before and after injuries caused by coccidiose

O objetivo deste trabalho foi avaliar o efeito da dieta suplementada com nucleotídeos sobre taxa de turnover da mucosa intestinal de frangos antes e após lesões causadas por coccidiose por meio de análise isotópica, utilizando a variação do carbono-13 em plantas C3 e C4. Foram utilizados 264 pintos submetidos a dois tratamentos: dieta controle e dieta suplementada com 0,07 por cento nucleotídeos. Os pintos possuíam sinais isotópicos em seus tecidos semelhantes ao de ditas C4. Após o alojamento, para avaliar taxa de turnover da mucosa, as aves receberam dietas predominantemente C3. Com 16 dias de idade, 50 por cento das aves de cada tratamento foram inoculadas com oocistos de Eimeria acervulina e, a partir de 21 dias, para avaliar a taxa de turnover após desafio, as aves passaram a receber dieta predominantemente C4. Amostras de mucosa foram analisadas isotopicamente por espectrometria de massa. Na fase inicial, a suplementação com nucleotídeos propiciou aceleração na troca do carbono na mucosa, com meia-vida de 1,06 e 1,01 dias para dieta controle e com nucleotídeos, respectivamente, acelerando o crescimento intestinal. Na fase de 21 a 42 dias de idade, para os grupos não desafiados com coccidiose, as meias-vidas do carbono foram 1,81 e 1,80 dias para dieta controle e com nucleotídeos, respectivamente, não havendo influência dos tratamentos. Porém, nos grupos desafiados, as meias-vidas foram 1,01 dias no grupo controle e 0,75 dias no que recebeu dieta com nucleotídeos, indicando maior turnover da mucosa nesse último grupo. A adição de nucleotídeos promove aceleração no processo de renovação da mucosa intestinal e na regeneração após danos causados por coccidiose.

The objective was to evaluate the effect of nucleotides supplementation diet on the intestinal mucosa turnover rate of broilers before and after injury caused by coccidiosis, through isotopic analysis, using the carbon-13 variation in C³ and C4 plants. It was used 264 chicks under two treatments: control diet and diet supplemented with 0.07 percent nucleotides. The chicks had isotopic signals in their tissues similar to C4 diet. After housing, to assess mucosal turnover rate, the birds were fed with a predominantly C3 diet. At 16 days of age, 50 percent of birds from each treatment were inoculated with Eimeria acervulina oocysts and starting from 21 days, to assess the mucosa turnover rate after challenge, the birds received predominantly C4 diet. Samples of intestinal mucosa were isotopically analyzed by mass spectrometry. In the initial phase, supplementation with nucleotides led acceleration in carbon trading in the mucosa, with half-lives of 1.06 and 1.01 days for control diet and with nucleotides, respectively, accelerating intestinal growth. During the 21 to 42 days of age, for not coccidiosis challenged groups, the carbon half-lives were 1.81 and 1.80 days for control diet and with nucleotides respectively, without any influence of the treatments. However, in the challenged groups, the half-lives were 1.01 days in control group and 0.75 days in group receiving nucleotides diet supplementetion, indicating a higher mucosa turnover rate in the latter group. The addition of nucleotides promotes acceleration in the cell renewal process of intestinal mucosa and in regeneration after damage caused by coccidiosis.

Enzima e simbiótico para frangos criados nos sistemas convencional e alternativo / Enzyme and symbiotic for broilers bred in conventional and alternative systems

O objetivo deste trabalho foi estudar os efeitos da inclusão de enzima e simbiótico nas rações de frangos de corte criados nos sistemas convencional e alternativo sobre o desempenho, rendimento de carcaça, cortes e gordura abdominal e também avaliar economicamente o uso destes aditivos em ambos os sistemas de criação. Foram utilizados 720 pintos machos Cobb, com um dia de idade, distribuídos em um delineamento em blocos casualizados no esquema fatorial 2x3, com dois sistemas de criação: convencional (com promotor de crescimento) e alternativo (sem promotor de crescimento) e três aditivos: sem outro aditivo (SA), com simbiótico (SI) e com enzima + simbiótico (SIE), com 4 repetições de 30 aves cada. Aos 42 dias de idade, o fator de produção (FP) foi menor (P<0,05) para aves SA (324), quando comparadas às tratadas com SI (334) e SIE (337). Aves criadas no sistema convencional apresentaram maior (P<0,05) FP (338), quando comparadas às do sistema de criação alternativo (325). No sistema alternativo, a conversão alimentar foi melhor (P<0,05) para aves SI (1,77), quando comparadas às SIE (1,82) e SA (1,85). O uso de SI e SIE favorece o desempenho dos frangos aos 42 dias de idade e não influencia o rendimento de carcaça, cortes e gordura abdominal, tanto no sistema convencional como no alternativo, sendo que estes aditivos aumentam os custos de produção em ambos os sistemas. O sistema alternativo de criação proporciona maior retorno econômico, apesar do menor fator de produção.

This research was aimed at evaluating the effects of enzyme and symbiotic inclusion in broilers diets bred in conventional and alternative systems on performance, carcass yield, cuts, abdominal fat and economic return these additives in both breeding systems. 720 one-day old male Cobb chicks were distributed in randomized blocks design according to a 2x3 factorial, two breeding systems: conventional (with growth promoter) and alternative (no growth promoter) and three additives: no additive (NA), symbiotic (SY) and symbiotic + enzyme (SYE), with four replicates of 30 broilers each. At 42 days old, the production factor (PF) was lower in NA broiler chickens (324) as broiler chickens supplemented with SY (334) and SYE (337). Broiler bred in conventional system showed higher PF (338) as broilers bred in alternative system (325). In alternative breeding system, the feed conversion was better in SY broilers (1.77) as SYE (1.82) and NA (1.85) broilers. The SY and SYE use improve the performance of broiler chickens at 42 days old and it doesnÆt affect carcass yield, cuts, and abdominal fat, in conventional or alternative system; moreover these additives increase production costs in both systems. Alternative system provide higher economic return, despite of lower production factor.