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To ensure the sustainability of agriculture and the production of safe food, supplementary irrigation is required for crops that are primarily rainfed, particularly in arid conditions. This study aimed to determine the water stress response of safflower (Carthamus tinctorius L.) under limited water conditions and to establish the crop water stress index (CWSI) as a basis for crop-based irrigation scheduling. Irrigation applications were conducted using the line-source sprinkler irrigation method to create three constraints (35, 75, and 100 % of the water requirement) and a rainfed condition (control plot) under different crop growth periods. The main plots consisted of three growth periods of safflower and only one supplementary irrigation during the vegetative, flowering, and ripening periods. The highest yield was obtained at 3.06 and 3.42 t ha­1 for 2019 and 2021, respectively, in the plot that was irrigated in each period during the growing season. The irrigation water (I) and water use efficiency (WUE) were 0.42 and 0.51 kg m­3 in the first year, and 0.47 and 0.59 kg m­3 in the second year, respectively, for the subject fully irrigated throughout the season. The upper base value, which can be utilized in calculations of the CWSI, was determined to be approximately 14.50. The lower base equation was obtained as Y = −4.9428 (VPD) + 19.121 at a statistical significance level of 1 % where Y is yield and VPD is vapor pressure deficit. The CWSI values calculated for each treatment ranged between −0.25 and 1.45. The threshold value at which irrigation should commence was determined to be 0.63, and it will serve as a valuable reference data source for irrigation scheduling.

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The study of genotypic relationships between drought tolerance indices and agronomic traits of interest in wheat breeding is useful for designing selection strategies. The objective of this research was to investigate the cause-and-effect relationships between agronomic traits and drought tolerance indices through the analysis of canonical correlations. Two trials (control and stress) were conducted in winter 2020 in Viçosa, MG, Brazil. The traits evaluated were: (days for heading, plant height, mass and number of grains per spike, mass of one hundred grains, and grain yield). Grain yield data from the control and stress conditions were used to construct five drought tolerance indices. The data were subjected to mixed model analysis for estimation of genetic parameters and prediction of genotypic values (REML/BLUP), and then the genotypic values were used to calculate the correlation coefficients between the traits. Two groups of traits were established for the study of canonical correlations, the first group consisting of agronomic traits and the second by drought tolerance indices. There was a significant genotype effect for all evaluated traits. The canonical pairs were significant, which indicated the existence of dependence between the groups. Days to heading trait can be used in the indirect selection of wheat genotypes for drought tolerance.

O estudo das relações genotípicas entre índices de tolerância à seca e caracteres agronômicos de interesse no melhoramento de trigo é útil para traçar estratégias de seleção. Objetivou-se com este trabalho investigar as relações de causa e efeito entre características agronômicas e índices de tolerância à seca via análise de correlações canônicas. Dois ensaios (controle e estresse) foram conduzidos no inverno de 2020 em Viçosa, MG, Brasil. Foram avaliados os caracteres (dias para o espigamento, altura da planta, massa e número de grãos por espiga, massa de cem grãos e rendimento de grãos). Os dados de produtividade dos ensaios de controle e estresse foram utilizados para construir cinco índices de tolerância à seca. Os dados foram submetidos à análise de modelos mistos para estimação dos parâmetros genéticos e predição dos valores genotípicos (REML/BLUP), em seguida, os valores genotípicos foram utilizados para calcular os coeficientes de correlação entre os caracteres. Dois grupos de caracteres foram estabelecidos para o estudo das correlações canônicas, sendo o primeiro grupo constituído pelas variáveis agronômicas e o segundo pelos índices de tolerância à seca. Houve efeito significativo de genótipo para todas as características avaliadas. Os pares canônicos foram significativos, o que indicou a existência de dependência entre os grupos. O caráter dias para o espigamento pode ser utilizado na seleção indireta de genótipos de trigo para tolerância à seca.

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Heat stress can affect several biological pathways. This study aimed to compare the effects of chronic and acute heat stress on the oxidative status and inflammatory responses of chick's hearts. Chronic and acute heat stress were induced in chicks, heart tissues were examined for morphological changes, and gene expression was analyzed in heart samples. Our results showed that prolonged heat exposure caused a dramatic reduction in chicks body weight, increased lesions, and ruptured cardiac muscle fibers in the hearts, confirming that chronic heat stress damages heart tissues and causes inflammation. Our gene expression results confirmed that heat stress induces oxidative stress and inflammation in the hearts of chicks, and this is evidenced by changes in the expression of NRF2 and CAT as antioxidant factors, NFκB and LITAF as anti-inflammatory factors, and changes in the expression of Leptin as an activator of Reactive Oxygen Species production and induction of proinflammatory factors. Our study also showed that the induction of anti-inflammatory and antioxidant genes was greater upon exposure to chronic heat stress than acute heat stress. These findings confirm that chickens generally tolerate chronic heat stress better than acute heat stress.(AU)

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This work wass designed to analyze the possibility of heavy metals inducing oxidative stress and biochemical perturbations effect on fresh water fish and their impact directly or indirectly on the human race. Due to continuous drainage of municipal waste, tanneries, and pesticides in Ganga River, lifeline of millions of people is heavily affected. The physico-chemical qualities of Ganga River were analyzed in quarterly basis during year 2018 to 2021, by taking the freshwater sample of different locations in Kanpur. While collecting the sample water the average temperature 27.6°, DO value of selected locations were fairly poor with an average of DO 6.67 mg L-1 and BOD ranged from 11.93 to 20.79 mg L-1. On the other hand the BOD ranged from 11.93 to 20.79 mg L-1 which is far more than WHO standards. Additionally, levels of antioxidants in enzymatic and non-enzymatic tissues serve as proxies for fish exposure to oxidant pollutants. Higher physico-chemical responses indicate contaminants and heavy metals may be playing an important role that have to be considered. The heavy metals are affecting the antioxidant defense system particularly seen in liver and kidney of fish and this affect on kidney and liver functioning as the concentrations of heavy metals rises. The relation between enzymatic activity and the metabolite showing negatively correlation that is noted highly significant to this study (r = -0.87, t = 10.14, p* ≤0.05).(AU)

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A truta arco-íris é essencial na dieta andina, especialmente em comunidades onde a qualidade da água é fundamental para a sua saúde e crescimento. Nossa pesquisa se concentra em como as condições ambientais do rio Chalhuanca afetam a saúde física, o estresse crônico e a capacidade imunológica da truta arco-íris, e qual é a relação desses efeitos com a segurança alimentar nas comunidades locais. Foram examinadas trutas juvenis do rio Chalhuanca, coletando 36 amostras em três pontos: antes de Cotaruse, depois de Caraibamba e passando por Chalhuanca. Os peixes foram medidos, pesados e amostras de sangue foram coletadas para avaliar componentes como glóbulos vermelhos, brancos, hemoglobina, hematócrito, glicose e cortisol. Também foi analisada a capacidade dos peixes de combater a bactéria E. colie foram medidos parâmetros físico-químicos e microbiológicos da água. Os resultados mostraram diferenças significativas na saúde das trutas entre as áreas. As trutas de Chalhuanca apresentaram pior condição corporal e anemia microcítica hipocrômica (hemoglobina: 6.1 g/dL, hematócrito: 29%). Além disso, observou-se uma alta proporção de estresse crônico nesta área. A qualidade da água também mostrou variações, com maiores concentrações de coliformes fecais (1200 UFC/100 mL) e menores níveis de oxigênio dissolvido (4.5 mg/L) em Chalhuanca, indicando um maior grau de contaminação.

Rainbow trout is essential in the Andean diet, especially in communities where water quality is essential for their health and growth. Our research focuses on how the environmental conditions of the Chalhuanca River affect the physical health, chronic stress, and immunological capacity of rainbow trout, and what the relationship of these effects is to food security in local communities. Juvenile trout from the Chalhuanca River were examined, collecting 36 samples at three points: before Cotaruse, after Caraibamba and passing Chalhuanca. The fish were measured, weighed and blood was drawn to evaluate components such as red and white blood cells, hemoglobin, hematocrit, glucose and cortisol. The ability of the fish to combat the E. colibacteria was also analyzed and physicochemical and microbiological parameters of the water were measured. The results showed significant differences in trout health between areas. Chalhuanca trout presented worse body condition and hypochromic microcytic anemia (hemoglobin: 6.1 g/dL, hematocrit: 29%). Furthermore, a high proportion of chronic stress was observed in this area. Water quality also showed variations, with higher concentrations of fecal coliforms (1200 CFU/100 mL) and lower levels of dissolved oxygen (4.5 mg/L) in Chalhuanca, indicating a higher degree of contamination.

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Purpose: Reflux esophagitis is a condition characterized by inflammation and irritation of the esophagus, resulting from the backflow of stomach acid and other gastric contents into the esophagus. Columbianadin is a coumarin derivative that exhibits anti-inflammatory and antioxidant effects. In this study, we tried to scrutinize the protective effect of Columbianadin against acute reflux esophagitis in rats. Methods: RAW 264.7 cells were utilized to assess cell viability and measure the production of inflammatory parameters. The rats received anesthesia, and reflux esophagitis was induced via ligation of pylorus and fore stomach and corpus junction. Rats received the oral administration of Columbianadin (25, 50 and 100 mg/kg) and omeprazole (20 mg/kg). The gastric secretion volume, acidity, and pH were measured. Additionally, the levels of oxidative stress parameters, cytokines, and inflammatory markers were determined. At the end of the study, mRNA expression was assessed. Results: Columbianadin remarkably suppressed the cell viability and production of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and prostaglandin (PGE2). Columbianadin treatment remarkably suppressed the secretion of gastric volume, total acidity and enhanced the pH level in the stomach. Columbianadin remarkably altered the level of hydrogen peroxidase, free iron, calcium, and plasma scavenging activity, sulfhydryl group; oxidative stress parameters like malonaldehyde, glutathione, superoxide dismutase, catalase, glutathione peroxidase; inflammatory cytokines viz., TNF-α, IL-6, IL-1ß, IL-10, IL-17, and monocyte chemoattractant protein-1; inflammatory parameters including PGE2, iNOS, COX-2, and nuclear kappa B factor (NF-κB). Columbianadin remarkably (P < 0.001) suppressed the mRNA expression TNF-α, IL-6, IL-1ß and plasminogen activator inhibitor-1. Conclusions: Columbianadin demonstrated a protective effect against acute reflux esophagitis via NF-κB pathway.

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Tadalafil, a potent phosphodiesterase inhibitor 5 (PDE-5), is commonly used for the management of erectile dysfunction. However, its therapeutic potential extends beyond this indication. This study aimed to investigate the impact of tadalafil on the recovery of testicular parenchyma in male Wistar rats exposed to testicular thermal stress. Fifty-four Wistar rats were subjected to testicular thermal stress and randomly assigned to receive either tadalafil treatment (TAD) or no treatment (control). TAD was administered intraperitoneally at a dose of either 0.9 mg/kg or 1.8 mg/kg. Biometric parameters, histopathological assessment of the testis, serum testosterone levels, oxidative stress, and interleukin levels were evaluated on days 7, 15, and 30 after thermal shock. The animals were euthanized at the end of each experimental period, and samples were collected. TAD treatment maintained testicular weight and reduced the testicular degenerative process up to day 7 post-injury. However, despite TAD therapy, serum testosterone levels were decreased in the treated groups at days 7 and 15 post-thermal stress. TAD also decreased TNF-α and NO levels at different doses but had no effect on IL-6. The treatment with TAD after heat shock demonstrated anti-inflammatory and antioxidant properties but did not prevent the aggravation of testicular lesions in subsequent periods, even with the systematic reduction in TNF-α and NO levels. Therefore, this selective PDE-5 inhibitor, at the dosages used, did not have a positive impact on testosterone levels during the post-thermal stress period, which could compromise the resumption of the spermatogenic process.(AU)

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ABSTRACT Purpose: To assess the effect of Amorphophallus campanulatus tuber (Ac) extract in the protection of diabetic nephropathy in streptozotocin (STZ) induced diabetic nephropathy (DN) rat model. Methods: Diabetes was induced with STZ (60 mg/kg, i.p.), and DN was confirmed after six weeks of STZ administration with the estimation of kidney function test. Further rats were treated with Ac 250 and 500 mg/kg p.o. for next four week. Oxidative stress and level of inflammatory cytokines were estimated in the kidney tissue of DN rats. Histopathology of kidney tissue was performed using hematoxylin and eosin staining. Results: There was improvement in the body weight of Ac treated groups than DN group of rats. Blood glucose level was observed to be reduced in Ac treated groups than DN group on 42nd and 70th day of protocol. Treatment with Ac ameliorated the altered level of kidney function tests (creatinine and BUN), enzymes of liver function (aspartate aminotransferase and alanine aminotransferase), and lipid profile in the serum of DN rats. Oxidative stress parameters (malondialdehyde and reactive oxygen species enhances and reduction in the level of glutathione and superoxide dismutase) and inflammatory cytokines such as interleukin-6, tumour necrosis factor-α, and monocyte chemoattractant protein-1 reduces in the tissue of Ac treated group than DN group. Treatment with Ac also attenuates the altered histopathological changes in the kidney tissue of DN rats. Conclusions: The report suggests that Ac protects renal injury in DN rats by regulating inflammatory cytokines and oxidative stress.

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Myrcia genus plants, like Myrcia pubipetala, traditionally used as hypoglycemic agents, hold promise for Type 1 Diabetes Mellitus (DM1) research but need more comprehensive chemical and pharmacological investigation. This is an experimental study involving controlled administration of treatments to a group of rats to assess their effects compared with a control group, investigating the effects of M. pubipetala on alloxan-induced Type 1 Diabetes Mellitus in rats. After the induction of diabetes, the rats received the hydroalcoholic extract (HAE) or aqueous fraction (AF) (25, 50, 100, or 150 mg kg-1) of M. pubipetala, or water. The results showed that diabetic rats presented cell damage in kidneys, oxidative stress, and high levels of glucose and triglycerides in their plasma and erythrocytes. The HAE (150 mg kg-1), per se, reduced lipid and protein oxidation, and the AF (150 mg kg-1) decreased lipoperoxidation. AF (150 mg kg-1), per se, decreased triglyceride levels. Conclusion: treatment with HAE and AF reduced oxidative damage, positively modulated antioxidant defenses, and exerted hypoglycemic and hypolipidemic effects, representing a potential adjuvant treatment for diabetes.(AU)

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The objective of this research was to determine the influence of heat stress, using the temperature-humidity index (THI), on the production and quality of native sperm of bulls. The effect of heat stress on the quantity of semen (mL), density of ejaculate (number of spermatozoa, 106/mL), gross sperm motility (1-5), number of frozen doses, and motility after freezing was analysed in 1,017 sperm samples taken from 32 Holstein-Friesian bulls, in the 2017-2019 period, at the Centre for Reproduction and Embryo Transfer in Serbia. The lowest amount of ejaculate (4.18±1.95 mL) and the lowest density of ejaculate (1,189.19±668.23 × 106/mL) were recorded under conditions of very strong heat stress on the day of semen collection. The level of heat stress measured on the day of semen collection did not affect sperm gross motility, number of frozen doses, and motility after freezing. The level of heat stress at the beginning of spermatogenesis, measured 60 days before semen collection, did not affect the amount of ejaculate and motility of spermatozoa after freezing, but at very strong stress, the lowest density of ejaculate (1,170.34±680.27 × 106/mL) and gross motility of spermatozoa were found (2.91±0.96). The lowest number of doses per ejaculate was recorded in conditions of moderate heat stress (396.6±157.71). Bulls older than 36 months had the best results according to all tested parameters of native sperm production and quality. The year in which the bulls produced semen did not affect density of ejaculate and sperm motility. The season of semen collection did not significantly affect the production and quality of native sperm, due to the practice of exploiting only bulls with the best sperm quality during the summer.(AU)

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An experiment was conducted to investigate the influence of in ovofeeding of black cumin extract (BC) on the intestinal morphology and physiological responses of broilers thermally challenged during incubation. The study involved the use of seven hundred Marshall broiler hatching eggs, which were assigned to 7 in ovo feeding treatments at embryonic day 17.5, as follows: eggs injected with 8 mg(EN), 6 mg(SN), 4 mg(FN), 2 mg (TN)BC, no in ovofeeding(NI), 0.9 %saline solution (SS), and 3 mg vitamin C (VC). Juvenile growth performance, plasma malondialdehyde(MDA), triiodothyronine (T3), superoxide dismutase (SOD), and haematologicaland serum biochemical indices were evaluated. The results revealed that the juvenile growth performance of SN birds was better than those of the NI, SS, FN and TN groups. The plasma SOD and T3of the birds of SN and VC were significantly higher (p <0.05)than the chickens of NI and SS treatments. The ileal crypt depth recorded in SN birds was lower (p <0.05) compared to SS and NI values. To conclude, in ovoblack cumin extract enhanced the gut health and lymphoid organs of broiler chickens with no pronounced effect on the thermotolerance of the birds at market age.(AU)

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Rice (Oryza sativa) is among the most important crops worldwide; however, rice crops demand high water consumption. Future projections indicate reduced water availability and severe drought events, which may affect rice crops as the cereal is highly sensitive to drought stress. Thus, cultivars with lower water demand for irrigation or drought escape capacities are among the strategies to address this issue. This study aimed to assess five mutant rice genotypes in terms of growth cycle length, other agronomic interest traits, and drought response in the reproductive stage. The mutant genotypes evaluated showed a shortening of the growth cycle compared to the original cultivar, BRS Pampeira, representing a drought escape strategy. In addition, mutations did not negatively affect plant height and crop yield. However, similar to the original cultivar, mutants are not tolerant to water deficit in the reproductive stage. The genotypes evaluated have potential to be released as early cycle cultivars, which can reduce water demand during the harvest season while presenting a drought escape strategy.

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Oxidative stress is the result of an imbalance between the production of oxidant precursors and the capacity of antioxidant defense. Oxygen free radicals play an important role in causing diseases. In this study, the protective effect of ethanolic avocado on apoptosis caused by oxidative damage in the tissue of albino rats was investigated. 24 male albino rats of the Faculty of Veterinary Medicine in Mosul, Iraq, which were kept in standard conditions for at least 10 days before and through the experimental work, were examined. Four groups of rats include the control group (healthy group), the group of male rats with ethanolic avocado consumption; The third group of male rats that were treated with 0.5% of hydrogen peroxide H2O2; and the fourth group of male rats that were treated with both 0.5% H2O2 and avocado ethanolic extract (50 mg kg-1 BW) for four weeks. After fixing the tissues of the liver, kidney, lung, spleen and testis in 10% buffered formalin, they were stained with hematoxylin. TUNEL assay was performed using the TUNEL cell death assay kit to detect apoptotic cells. In this investigation, the histology results in four groups of rats showed that in the rats that were treated with avocado, there were minor tissue changes in their liver, kidney, and intestine, and the tissues of these organs were healthy. In TUNEL staining, it was also shown that there are no apoptotic cells in the liver, kidney and testis cells in avocado-treated rats. The results showed that ethanolic Avocado is useful against oxidative stress damage and it may be used to protect tissues against oxidative stress.(AU)

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Purpose: XinJiaCongRongTuSiZiWan (XJCRTSZW) is a traditional Chinese medicine compound for invigorating the kidney, nourishing blood, and promoting blood circulation. This study aimed to explore the effect of XJCRTSZW on triptolide (TP)-induced oxidative stress injury. Methods: Adult female Sprague-Dawley rats and human ovarian granulosa cell lines were treated with TP and XJCRTSZW. Hematoxylin and eosin staining, enzyme-linked immunosorbent assay, flow cytometry, CCK-8, JC-1 staining, transmission electron microscopy, reverse transcription-quantitative polymerase chain reaction, and Western blotting were performed in this study. Results: XJCRTSZW treatment observably ameliorated the TP-induced pathological symptoms. Furthermore, XJCRTSZW treatment observably enhanced the TP-induced reduction of estradiol, anti-Mullerian hormone, progesterone, superoxide dismutase, ATP content, mitochondrial membrane potential, p62, and Hsp60 mRNA, and protein levels in vivo and in vitro (p < 0.05). However, TP-induced elevation of follicle stimulating hormone and luteinizing hormone concentrations, malondialdehyde levels, reactive oxygen species levels, apoptosis rate, mitophagy, and the mRNA and protein expressions of LC3-II/LC3-I, PTEN-induced kinase 1 (PINK1), and Parkin were decreased (p < 0.05). In addition, XJCRTSZW treatment markedly increased cell viability in vitro (p < 0.05). Conclusions: XJCRTSZW protects TP-induced rats from oxidative stress injury via the mitophagy-mediated PINK1/Parkin pathway.

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ABSTRACT Purpose: To evaluate the neuroprotective effect of resveratrol, urapidil, and a combined administration of these drugs against middle cerebral artery occlusion (MCAO) induced ischemia/reperfusion (IR) injury model in rats. Methods: Thirty-five rats were divided into five groups of seven animals each. Animals in IR, IR resveratrol (IRr), IR urapidil (IRu), and IR + combination of resveratrol and urapidil (IRc) were exposed to MCAO induced cerebral ischemia reperfusion injury model. Rats in IRr and IRu groups received 30-mg/kg resveratrol and 5-mg/kg urapidil respectively. Animals in IRc received a combined treatment of both drugs. At the end of the study, brain tissues were used for oxidative stress (malondialdehyde, glutathione, and superoxide dismutase), pro-apoptotic caspase-3, anti-apoptotic Bcl-2, and pro-inflammatory tumor necrosis factor-α cytokine level measurements. Results: The MCAO model successfully replicated IR injury with significant histopathological changes, elevated tissue oxidative stress, and upregulated apoptotic and inflammatory protein expression in IR group compared to control group (p < 0.001). All parameters were significantly alleviated in IRr group compared to IR group (all p < 0.05). In IRu group, all parameters except for caspase-3 and Bcl-2 were also significantly different than IR group (all p < 0.05). The IRc group showed the biggest difference compared to IR group in all parameters (all p < 0.001). The IRc had higher superoxide dismutase and Bcl-2 levels, and lower caspase-3 levels compared to both IRr and IRu groups (all p < 0.05). Also, the IRc group had lower MDA and TNF-α levels compared to IRu group (all p < 0.05). Conclusions: The results indicate that combined treatment of resveratrol and urapidil may be a novel strategy to downregulate neurodegeneration in cerebral IR injury.

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This study examined the impact of a 37.5 °C temperature on chick embryos during the hatching period (18-21 days of incubation) and its subsequent effect on hatchery results and the thermotolerance of broiler chicks from 28-40 days of rearing. For hatchery results, the study involved 16 trays per treatment. For performance, the study involved 360 broiler chicks from two distinct hatching temperature conditions: a control group (36.5 °C and 65% relative humidity (RH)) and a thermal manipulation group (37.5 °C/6 h/d from 18 to 21 days of incubation with 65% RH). The chicks were reared in a thermoneutral temperature until day 28. Subsequently, on day 28 post-hatch, the chicks were randomly assigned to a 2 × 2 arrangement to assess the differences in thermotolerance acquisition. The primary factors were embryo thermal manipulation in the hatcher and the thermal environmental rearing from day 28 until day 40 (thermoneutrality (at a constant 23.0 °C) or thermal environmental challenge (30.0 °C/6 h/d)). No effect was observed on hatchability, residual analysis of unhatched eggs, and chick quality. No interaction was observed between treatments for performance or cloacal temperature from day 28 to day 40. However, birds reared in a thermoneutral environment exhibited higher feed intake and body weight gain from day 28 to day 40 and a lower feed conversion ratio than the birds reared in a cyclic heat temperature environment. An increase of 1 °C/6 h/d in the hatcher from day 18-21 does not affect hatchery results or enhance the adaptability of broilers to a heat stress environment during the final rearing period.(AU)

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This study aimed to characterize the occurrence, duration, and intensity of the flushes of vegetative growth in two peach cultivars of Prunus persica L. Batsch, grown as a pioneer endeavor at a high-altitude tropical climate site in the State of Minas Gerais, Brazil. The observational experiment was carried out in 2017/18 and 2018/19 on the 'Tropic Beauty' and 'BRS Kampai' cultivars by an evaluation of the number and duration of flushes of vegetative growth during the year over two cycles. The number of fruit-bearing shoots, total number of leaves and shoot length were also assessed. At harvest, fruit load and diameter were determined and grouped into diameter ranges. The number of hours recorded at different temperature ranges, < 10.0 °C; 10.1-15.0 °C; 15.1-20.0 °C; 20.1-25.0 °C; > 25.1 °C, were summed separately and divided into daily and nightly periods. The peach tree has an unusual vegetative growth pattern when cultivated in a tropical area, which occurs in two flushes, with the first flush occurring from budbreak to fruit harvest between June and Sept, forming short shoots (less than 10 cm), with early shoot growth cessation, with a limited leaf number that can potentially diminish the supply of carbohydrates to the fruit, leading to smaller growth. The second flush occurs after harvest, between Oct and Dec, when there is an increase in daily temperature and precipitation, and no competition with fruits. Notabily, these second flush shoots grow with greater vigor and regularization of the growth cycle, forming fruit-bearing shoots with abundant leaf and flower buds for the next production cycle.

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Abiotic stresses, such as heat, drought and salinity, affect the development of wheat crop and hinder its expansion to the central region of Brazil. The identification of genotypes tolerant to these conditions is important for improving yield performance. The present research evaluated the impact of different abiotic stresses on germination and seedling development and selected wheat genotypes tolerant to these stresses, using multi-trait analysis. Heat, drought and salinity stresses were induced in seeds of 23 wheat genotypes. Seed germination, seedling length and dry mass were evaluated. An adaptability and stability model and a multi-trait selection index were applied to the data. Drought and salinity negatively affected the development of seedlings of the 23 evaluated genotypes. However, the VI 14055, ORS Madre Pérola and BRS 404 genotypes conferred the best adaptability and stability results and were selected by the MGIDI, which revealed that great performance can be achieved in regions with potential for abiotic stress, in the early stages of development.

Estresses abióticos como calor, seca e salinidade afetam o desenvolvimento da cultura do trigo e dificulta a sua expansão para a região central do Brasil. A identificação de genótipos tolerantes a estas condições são importantes para o melhoramento genético da cultura. Logo, objetivou-se avaliar o impacto de diferentes estresses abióticos sobre parâmetros de germinação e do desenvolvimento de plântulas de trigo via análise multi-trait. Estresses térmico por calor, seca e salinidade foram induzidos em sementes de 23 genótipos de trigo. Foram avaliados a germinação das sementes, comprimento e massa seca da plântula. Foram aplicados sobre os dados, modelo de adaptabilidade e estabilidade e índice de seleção multi-trait. Os ambientes de estresse abiótico por seca e salinidade afetaram negativamente o desenvolvimento das plântulas dos 23 genótipos avaliados. Contudo, os genótipos VI 14055, ORS Madre Pérola e BRS 404 combinam os melhores resultados de adaptabilidade e estabilidade e foram selecionados pelo MGIDI. Por meio disso, estes genótipos são potencias para serem recomendados às regiões em que se ocorre estes tipos de estresses abióticos.

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Abstract Hibernation is a natural condition of animals that lives in the temperate zone, although some tropical lizards also experience hibernation annually, such as the lizard native from South America, Salvator merianae, or "tegu" lizard. Even though physiological and metabolic characteristic associated with hibernation have been extensively studied, possible alterations in the red blood cells (RBC) integrity during this period remains unclear. Dehydration and fasting are natural consequences of hibernating for several months and it could be related to some cellular modifications. In this study, we investigated if the osmotic tolerance of RBCs of tegu lizard under hibernation is different from the cells obtained from animals while normal activity. Additionally, we indirectly investigated if the RBCs membrane of hibernating tegus could be associated with oxidation by quantifying oxidized biomolecules and the activity of antioxidant enzymes. Our findings suggest that RBCs are more fragile during the hibernation period, although we did not find evidence of an oxidative stress scenario associated with the accentuated fragility. Even though we did not exclude the possibility of oxidative damage during hibernation, we suggested that an increased RBCs volume as a consequence of hypoosmotic blood during hibernation could also affect RBCs integrity as noted.

Resumo A hibernação é uma condição natural dos animais que vivem na zona temperada, embora alguns lagartos tropicais também experenciem hibernação anualmente, como é o caso do lagarto nativo da América do Sul, Salvator merianae ou "teiú". Embora as características fisiológicas e metabólicas associadas à hibernação tenham sido amplamente estudadas, possíveis alterações na integridade das hemácias durante esse período ainda permanecem obscuras. A desidratação e o jejum são consequências naturais da hibernação por vários meses e podem estar relacionadas a algumas modificações celulares. Neste estudo, investigamos se a tolerância osmótica de hemácias do lagarto teiú sob hibernação são diferentes das células obtidas de animais em atividade normal. Além disso, investigamos indiretamente por meio da quantificação de biomoléculas oxidadas e da atividade de enzimas antioxidantes se a membrana das hemácias dos teiús em hibernação poderia estar associada à oxidação. Nossos resultados sugerem que as hemácias possuem maior fragilidade durante o período de hibernação, embora não tenhamos encontrado evidências de um cenário de estresse oxidativo associado à essa fragilidade acentuada. Embora não tenhamos excluído a possibilidade de dano oxidativo durante a hibernação, sugerimos que um aumento no volume das hemácias como consequência de sangue hipoosmótico durante a hibernação também poderia afetar a integridade de hemácias, tal como foi observado.

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Abstract This study was carried out to evaluate the effect of Glutamine, as a dipeptide or a free amino acid form, on the progression of burn injuries in rats. Thirty male Wistar rats were burned with a comb metal plate heated in boiling water (98 °C) for three minutes, creating four rectangular full-thickness burn areas separated by three unburned interspaces (zone of stasis) in both dorsum sides. The animals were randomized into three groups (n=10): saline solution (G1-Control) and treated groups that orally received Glutamine as dipeptide (G2-Dip) or free amino acid (G3-FreeAA). Two and seven days after burn injury, lesions were photographed for unburned interspaces necrosis evolution assessment. Seven days after injury, glutathione seric was measured and histopathological analysis was performed. By photographs, there was a significant reduction in necrosis progression in G3-Free-AA between days two and seven. Histopathological analysis at day 7 showed a significantly higher stasis zone without necrosis and a higher number of fibroblasts in G2-Dip and G3-FreeAA compared with G1-Control. Also, glutathione serum dosage was higher in G2-Dip. The plasmatic glutathione levels were higher in the G2-Dip than the G1-Control, and there was a trend to higher levels in G3-FreeAA. The reduction in histological lesions, greater production of fibroblasts, and greater amounts of glutathione may have benefited the evolution of burn necrosis, which showed greater preservation of interspaces.

Resumo Este estudo foi realizado para avaliar o efeito da Glutamina, como um dipeptídeo ou forma de aminoácido livre, na progressão de queimaduras em ratos. Trinta ratos Wistar machos foram queimados com um pente de metal aquecido em água fervente (98 °C) por três minutos, criando quatro áreas retangulares queimadas separadas por três interesespaços não queimados (zona de estase) em ambos os lados do dorso. Os animais foram randomizados em três grupos (n = 10): solução salina (G1-Controle) e grupos tratados que receberam glutamina via oral como dipeptídeo (G2-Dip) ou aminoácido livre (G3-FreeAA). Dois e sete dias após a queimadura, as lesões foram fotografadas para avaliação da evolução da necrose entre os espaços não queimados. Sete dias após a lesão, foi dosada a glutationa sérica e realizada análise histopatológica. Pelas fotografias, houve uma redução significativa na progressão da necrose no G3-Free-AA entre os dias dois e sete. A análise histopatológica no dia 7 mostrou uma zona de estase significativamente maior sem necrose e número mais elevado de fibroblastos em G2-Dip e G3-FreeAA em comparação com G1-Controle. Os níveis plasmáticos de glutationa foram maiores no G2-Dip em relação ao G1-Controle, e houve tendência a níveis mais elevados no G3-FreeAA. A redução das lesões histológicas, maior produção de fibroblastos, maior quantidade de glutationa podem ter beneficiado a evolução da necrose da queimadura, que mostrou maior preservação dos interespaços.