Patrício Gomes Leite

This study evaluated the physiological responses and carcass traits of Japanese quails (Coturnix coturnix japonica) fed diets supplemented with the macroalga Gracilaria birdiae across different thermal environments. A completely randomized 4 × 3 factorial design tested four macroalgae inclusion levels (0, 3, 6, and 9%) and three temperatures (25, 29, and 33 °C). Cloacal temperature (CT), respiratory rate (RR), and surface temperature (ST) were not significantly influenced by algal inclusion (P = 0.1413 and P = 0.9616, respectively). On the other hand, RR decreased significantly in quails receiving macroalgae (P = 0.0002), indicating improved heat dissipation. No interaction between dietary algae levels and temperature was detected for absolute or relative organ weights (P>0.05). Inclusion of 9% Gracilaria birdiae in the diet of female Japanese quails was safe and effective at 29 °C, maintaining live weight, carcass quality, and organ development. At 33 °C, however, breast yield decreased significantly, highlighting the importance of heat-stress management strategies.

A cultura da soja é a principal commoditie agrícola do Brasil e vem sendo expandida em diferentes regiões do país, notadamente na região de transição Amazônia-Cerrado, onde são incipientes estudos referentes ao manejo integrado de plantas daninhas (MIPD) tolerantes ao glifosato e seu impacto na produtividade. Neste sentido, objetivou-se analisar o desempenho de herbicidas pré-emergentes lipofílicos sobre plantas daninhas tolerantes a glifosato, em sistemas de produção convencional e plantio direto. Para isto, realizou-se um experimento delineado em blocos casualizados, sob arranjo fatorial 5×2 e quatro repetições. O primeiro fator consistiu em cinco tratamentos pré-emergentes, sendo eles: Testemunha (sem herbicida), flumioxazina + piroxasulfona, flumioxazina + imazetapir, S-metolacloro e S-metolacloro + fomesafem; enquanto o segundo fator correspondeu a dois sistemas de produção: convencional e plantio direto. Avaliaram-se a eficiência no controle de plantas daninhas, população de plantas daninhas, fenologia de plantas daninhas, bem como, o índice de clorofila foliar (a, b e total), índice NDVI (Índice de Vegetação por Diferença Normalizada), fitotoxicidade e produtividade da soja. Os resultados apontaram a ocorrência de dez plantas daninhas compartilhadas pelos sistemas convencional e plantio direto, dentre as quais, cinco espécies têm registro de resistência a herbicidas na sojicultura brasileira. O uso de flumioxazina + piroxasulfona em sistema de plantio direto (SPD) obteve uma produtividade 37% superior à testemunha (sem herbicida e sem palha). A presença de palha sobre o solo (±17 t ha-1) contribuiu para o manejo integrado de plantas daninhas tolerantes a glifosato e aumentou o desempenho dos herbicidas pré-emergentes lipofílicos. Palavras-chave: Glycine max L. Banco de Sementes de Plantas Daninhas. Levantamento de Plantas Daninhas. Manejo Integrado de Plantas Daninhas. Resistência a Herbicidas.

The objective of this research was to reduce the dimensionality of the original set of variables by eliminating redundant information and enabling the recommendation of variables to be evaluated in future experiments. A total of 240 European quail chicks (Coturnix coturnix Japonica), aged one day and with an average weight of 8 g, standard deviation ± 0.50 g, were analyzed in this study. It was observed that weight gain (32.75%), liver (37.19%), and intestine (33.54%) exhibited the highest coefficients of variation. On the other hand, cloacal temperature had the lowest coefficient of variation (0.88%), indicating low variability in respiratory rate (16.23%) and surface temperature (3.55%). In total, the three main components together explained 74.65% of the data variation, indicating that, among the 16 variables analyzed, 13 were significant in explaining the observed variability. The variables heart weight, liver, and gizzard were not considered relevant for this study once their impact on the multivariate analysis was minimal. These results have direct implications for the food industry, as they reveal factors that affect meat quality and consumer acceptance.

The objective of this research was to reduce the dimensionality of the original set of variables by eliminating redundant information and enabling the recommendation of variables to be evaluated in future experiments. A total of 240 European quail chicks (Coturnix coturnix Japonica), aged 1 day and with an average weight of 8 ± 0.50 g, were used. It was observed that weight gain (32.75%), liver (37.19%), and intestine (33.54%) exhibited the highest coefficients of variation. On the other hand, cloacal temperature had the lowest coefficient of variation (0.88%), indicating low variability in respiratory rate (16.23%) and surface temperature (3.55%). In total, the three main components together explain 74.65% of the data variation, indicating that, among the 16 variables analyzed, 13 were significant in explaining the observed variability. The variables heart weight, liver, and gizzard were not considered relevant for this study, as their impact on the multivariate analysis was minimal. These results have direct implications for the food industry, as they reveal factors that affect meat quality and consumer acceptance.

O manejo preventivo de plantas daninhas tolerantes a herbicidas é um dos principais gargalos para o aumento de produtividade na cultura da soja. Objetivou-se analisar o desempenho de herbicidas pré-emergentes e pós-emergentes sobre o controle de espécies tolerantes ao glifosato no cerrado maranhense. A pesquisa foi conduzida durante o período chuvoso, em lavoura comercial de soja situada na cidade de Brejo, Maranhão, Brasil, entre os meses de janeiro e junho de 2022. O experimento foi delineado em arranjo de faixas, com 5 tratamentos e 6 repetições. Testaram-se dois tratamentos pós-emergentes residuais e três pré-emergentes, compreendidos por glifosato + 2,4-D (2.096 + 670), glifosato + saflufenacil (1.397 + 35), diclosulam + imazetapir (30 + 80), flumioxazina + imazetapir (50 + 100) e flumioxazina + piroxasulfona (60 + 80 g i.a. ou e.a. ha-1). Realizou-se o monitoramento de plantas daninhas com a estimativa de índices fitossociológicos e porcentagem de controle, bem como, avaliaram-se a fitotoxicidade, densidade, fenologia e produtividade da soja. Ao término do estudo, identificaram-se 18 espécies de plantas daninhas, distribuídas em 15 gêneros e 13 famílias botânicas. As espécies Eleusine indica, Spermacoce verticillata e Cyperus iria não foram controladas por nenhum dos tratamentos testado, obtendo uma suspeita de resistência ao glifosato, a qual deverá ser investigada em estudos futuros. O uso de herbicidas pré-emergentes foi mais efetivo para o controle de plantas daninhas eudicotiledôneas, como a Scoparia dulcis, e alcançou uma produtividade de 4.047 kg ha-1, para a aplicação da mistura de flumioxazina (50 g i.a. ha-1) + imazetapir (100 g e.a. ha-1).

The increase of human activities across different regions of Brazil has impacted biodiversity loss and water availability, negatively affecting natural resources, as well as social and economic factors, especially in the Amazon-Cerrado transition region. The aim of this work was to analyze changes in land use and land cover from 1986 to 2022, as well as to project a scenario for the year 2034 in the Amazon-Cerrado transition region, Maranhão, Brazil. The study was conducted in the municipality of Chapadinha, in the Eastern Maranhão Mesoregion. The Annual Land Use and Land Cover Mapping Project in Brazil (MAPBIOMAS) was used for the temporal and spatial analysis of Land Use, Land-Use Change, and Forestry (LULUCF). The generation of the future forecast model for LULUCF was obtained by applying linear regression to the main land use classes in the municipality of Chapadinha..The results show that from 1986 to 2022, there was an expansion of Pasture (255.2%), Urban Infrastructure (120.5%), and Soy (116.2%), along with significant reductions in the classes of Savanna Formation (24.67%), and Water Bodies (69.32%). In this study, Urban Infrastructure and Pasture were the land use classes that most affected Water Bodies.

Salinity affects physiological processes, such as photosynthesis, in various agricultural crops, such as sorghum, around the world. Thus, mitigating techniques such as priming seeds with hydrogen peroxide (H₂O₂) can increase plant tolerance to salt stress. Thus, the objective of present study was to evaluate the priming of seeds with hydrogen peroxide on gas exchange and shoot phytomass of sorghum grown under salt stress. The treatments were distributed in a randomized block design, in a 4 × 4 factorial arrangement, with four levels of electrical conductivity of irrigation water - (ECw- 0.3, 1.5, 3.5, and 5.5 dS m^-1) and four concentrations of H₂O₂ (0, 6, 12, and 18 μM L^-1), with three replications. The salinity of the water reduced gas exchange, shoot fresh and dry mass, in addition to shoot moisture content in sorghum plants. However, priming the seeds with H₂O₂ improved gas exchange and the accumulation of plant dry mass. Seed priming with H₂O₂ at dose of 8.2 µM increases the acclimatization of sorghum plants under salt stress.

This study aimed to estimate the heat flux through sensitive mechanisms and respiratory evaporation of Japanese quails kept in thermoneutral and warm environments, using simple environmental and physiological measures. 192 nine-week-old quails were used, distributed in a completely randomized design at two temperatures (T1 = 24°C and T2 = 32°C), with 12 replicates of eight birds each, with an experimental period of 63 days, divided into three 21-day periods. Physiological measurements of respiratory rate (RR), cloacal temperature (TC), and body surface temperature (TS) were measured twice a week. The behavior of the energy balance in the climatic chambers was obtained using the total thermal energy exchanges per unit surface area of the birds, derived from the sum of sensible (radiation and convection) and latent heat exchanges. Respiratory rate (P<.0001), surface temperature (P<.0001), and cloacal temperature (P=0.0047) were higher in the 32°C environment. The expired air temperature (P<.0001) and heat loss by respiratory evaporation (P<.0001) showed higher values when the quails were in an environment of 32°C, while the heat losses by convection (P<.0001) and radiation (P<.0001) were higher in a thermal comfort environment. In Japanese quails kept in a controlled environment, sensible heat dissipation by convection is the main way to eliminate excess thermal energy, when the air temperature is up to 32ºC.

This study aimed to evaluate the influence of the inclusion of marine macroalgae bran of the species Sargassum sp at increasing levels (0; 2.5; 5 and 7.5 %) on the productive performance and physiological responses of European quail (Coturnix coturnix coturnix), in two types of environments. A total of 480 European quail chicks (Coturnix coturnix coturnix) were used, distributed in an entirely randomized design, with four levels of bran inclusion (0.0; 2.5; 5.0, and 7.5 %), 6 repetitions with 10 birds in each experimental plot. Water consumption was higher and feed intake was lower in the climatic chamber in all phases, presenting regression and interaction effects for both environments as a function of sargassum bran inclusion. Thus, feed conversion and weight gain were also influenced and similar to the feed and water intake results. For the physiological variables, no interactions between the environments were identified as a function of sargassum bran inclusion in any of the phases. However, there were significant differences between the environments. In the first phase, the respiratory rate variable was higher in the climatic chamber and there was no significant difference in the other phases. It is recommended the inclusion of up to 7.5% of sargassum bran in the diet of European quail in all phases, without compromising their productive performance and maintaining the physiological variables within the normal range in environments similar to those simulated in the open housing. However, under heat stress conditions, the quail are compromised, and the inclusion did not have the effect of maintaining the performance of the birds.

The objective of this research was to evaluate the productive performance, carcass quality, and intestinal biometry of European quails (Coturnix coturnix coturnix), kept under cyclic heat stress (air temperature of 32.5°C±0.5) receiving a ration with different concentrations (0, 2.5, 5, and 7.5%) of seaweed meal of Sargassum sp. A total of 240 quails were used, distributed in a completely randomized design with 4 levels of bran inclusion, 6 replications, and 10 birds per experimental unit. An analysis of variance (ANOVA) was performed, and the means were compared by Tukey's test with 5% probability and subjected to regression by PROC REG of SAS® (2002). No similarity was observed in water and feed consumption between treatments. There was a significant difference in most of the variables studied, with a significant difference only occurring in the dorsum, gizzard, and large intestine. Therefore, it is recommended to include up to 7.5% of sargassum bran in the diet of European quails kept under a 12-h heat cycle (32°C±0.5).