Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.094
Filtrar
1.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469183

Resumo

Abstract In the state of São Paulo, the main sugarcane producing region of the world, two species of scale insects have frequently occurred, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) and Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). To map the distribution and abundance of these species, 17 sugarcane producing fields, distributed in six mesoregions in São Paulo, were evaluated in August 2017 and, January, February, June and July 2018 during the ripening phase. The study on the seasonality of these species, by the presence or absence of the scale insects during the phenological cycle of the plant, was conducted between August 2017 and July 2018 in two sugarcane producing fields in the municipality of Jaboticabal, São Paulo, Brazil. The presence of S. sacchari was found in all the analyzed locations, and A. takahashii in twelve. Both scale insects showed significant difference of infestation in the nodes region of the stems during the ripening phase in one of the studied locations. The aclerdid presented significant difference by infestation in one site during the ripening phase of the plant. The pseudococcid infested a greater number of nodes in the following phases of development; vegetative, grand growth and ripening in both studied areas, but it was in one site during the ripening phase that presented the greatest difference. Although the pink sugarcane mealybug was more abundant than A. takahashii in both studies, there were no patterns of relationships between the numbers of individuals to geographical locations and temperature.


Resumo No estado de São Paulo, principal região produtora de cana-de-açúcar do mundo, duas espécies de cochonilhas têm ocorrido frequentemente, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) e Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). Para mapear a distribuição e abundância destas espécies, 17 regiões produtoras de cana-de-açúcar, distribuídas em seis mesorregiões de São Paulo, foram avaliadas em agosto de 2017 e janeiro, fevereiro, junho e julho de 2018, durante a fase de maturação. O estudo da sazonalidade destas espécies, pela presença ou ausência das cochonilhas durante o ciclo fenológico da planta, foi conduzido entre agosto de 2017 e julho de 2018 em duas regiões produtoras de cana-de-açúcar no município de Jaboticabal, São Paulo, Brasil. Saccharicoccus sacchari foi encontrada em todas as localidades analisadas, e A. takahashii em 12. Ambas cochonilhas mostraram diferença significativa de infestação na região dos nós dos colmos durante a fase de maturação em uma das localidades estudadas. O aclerdídeo apresentou diferença significativa pela infestação em uma localidade durante a fase de maturação da planta. O pseudococcídeo infestou um grande número de nós nas seguintes fases de desenvolvimento; perfilhamento, crescimento vegetativo e maturação em ambas áreas estudadas, mas foi em uma localidade durante a fase de maturação que apresentou a maior diferença. Embora a cochonilha rosada da cana-de-açúcar foi mais abundante do que A. takahashii em ambos estudos, não houve padrões de relações entre o número de indivíduos com a localização geográfica e temperatura.

2.
Rev. bras. zootec ; 52: e20220116, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1449864

Resumo

The objective of this study was to assess behavior patterns in Brazilian farm milk prices. We employed a structural time series techniques model, the Unobserved Component Model (UCM), which is part of the family of State Space models, to assess the trend, seasonality, cyclical behavior, and impacts of exogenous regressors on aggregated farm milk price behavior in Brazil from January 2005 to December 2019. We tested five alternative models with different regressors using the monthly national average prices of milk paid to farmers. The fit of the models was assessed with Akaike information criterion and Bayesian information criterion. Predictions were assessed by the root mean squared error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE). All models demonstrated a high degree of accuracy. Trends, seasonality, and two cycles were statistically significant, with the trend and long-period cycle contributing the most to price variation. Exogenous factors such as feed cost and international dairy product prices also had significant positive effects on the level of Brazil's farm milk prices. All models demonstrated a high degree of accuracy, which may indicate their usefulness for price forecasting and policy formulation.(AU)


Assuntos
24444 , Leite/fisiologia , Fatores Econômicos , Brasil , Comércio/economia
3.
Pap. avulsos zool ; 63: e202363028, 2023. tab, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1510033

Resumo

The Black Skimmer (Rynchops niger) and the Large-billed Tern (Phaetusa simplex) are two migratory waterbirds that breed simultaneously on many river beaches in South America. Both are polytypic taxa with little information about the distribution and nonbreeding ("wintering") areas. Based on data from the literature, citizen science websites, fieldwork, and specimens housed in natural history museums, we revised the distribution of some of the main breeding colonies in South America, comparing it with continental rainy cycles to identify generalities about the role of precipitation seasonality on the defining intratropical migration routes of these species. Our data suggest that the seasonal precipitation cycle of South America directly influences the reproductive timing and distribution of both species, which is largely circumscribed by South America's rivers. After breeding on sandy beaches during the dry season, both species disperse in small groups or even individually ­ not in large flocks as seen in breeding areas ­ making it difficult to find general migration patterns during the rainy season. Nonetheless, individuals of both species tend to follow the course of the largest rivers of the continent and even alternative routes to disperse into several areas throughout South America during the nonbreeding season.(AU)


Assuntos
Migração Animal/fisiologia , Charadriiformes/fisiologia , Filogeografia , América do Sul , Estação Chuvosa
4.
Braz. j. biol ; 83: e250879, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339383

Resumo

Abstract In the state of São Paulo, the main sugarcane producing region of the world, two species of scale insects have frequently occurred, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) and Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). To map the distribution and abundance of these species, 17 sugarcane producing fields, distributed in six mesoregions in São Paulo, were evaluated in August 2017 and, January, February, June and July 2018 during the ripening phase. The study on the seasonality of these species, by the presence or absence of the scale insects during the phenological cycle of the plant, was conducted between August 2017 and July 2018 in two sugarcane producing fields in the municipality of Jaboticabal, São Paulo, Brazil. The presence of S. sacchari was found in all the analyzed locations, and A. takahashii in twelve. Both scale insects showed significant difference of infestation in the node's region of the stems during the ripening phase in one of the studied locations. The aclerdid presented significant difference by infestation in one site during the ripening phase of the plant. The pseudococcid infested a greater number of nodes in the following phases of development; vegetative, grand growth and ripening in both studied areas, but it was in one site during the ripening phase that presented the greatest difference. Although the pink sugarcane mealybug was more abundant than A. takahashii in both studies, there were no patterns of relationships between the numbers of individuals to geographical locations and temperature.


Resumo No estado de São Paulo, principal região produtora de cana-de-açúcar do mundo, duas espécies de cochonilhas têm ocorrido frequentemente, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) e Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). Para mapear a distribuição e abundância destas espécies, 17 regiões produtoras de cana-de-açúcar, distribuídas em seis mesorregiões de São Paulo, foram avaliadas em agosto de 2017 e janeiro, fevereiro, junho e julho de 2018, durante a fase de maturação. O estudo da sazonalidade destas espécies, pela presença ou ausência das cochonilhas durante o ciclo fenológico da planta, foi conduzido entre agosto de 2017 e julho de 2018 em duas regiões produtoras de cana-de-açúcar no município de Jaboticabal, São Paulo, Brasil. Saccharicoccus sacchari foi encontrada em todas as localidades analisadas, e A. takahashii em 12. Ambas cochonilhas mostraram diferença significativa de infestação na região dos nós dos colmos durante a fase de maturação em uma das localidades estudadas. O aclerdídeo apresentou diferença significativa pela infestação em uma localidade durante a fase de maturação da planta. O pseudococcídeo infestou um grande número de nós nas seguintes fases de desenvolvimento; perfilhamento, crescimento vegetativo e maturação em ambas áreas estudadas, mas foi em uma localidade durante a fase de maturação que apresentou a maior diferença. Embora a cochonilha rosada da cana-de-açúcar foi mais abundante do que A. takahashii em ambos estudos, não houve padrões de relações entre o número de indivíduos com a localização geográfica e temperatura.


Assuntos
Humanos , Animais , Saccharum , Hemípteros , Temperatura , Brasil , Produtos Agrícolas
5.
Acta sci., Anim. sci ; 45: e57518, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1396821

Resumo

The objective was to evaluate fertility, cyclicality behavior, and sexual performance of Pantaneiro sheep throughout the year's photoperiods in Mato Grosso do Sul - Brazil. Two experiments were conducted. In experiment one, the ewes used aged between 2 and 4 years, distributed in three homogeneous groups of 54 animals and subjected to reproductive evaluation in three different predefined luminosity periods, consisting of autumn (11h 45 min.), spring (12h 30 min.), and summer (12h 55 min.). The characteristics studied were body weight (BW), body condition score (BCC), estrus distribution (EST), percentage of pregnant females per cycle (%P), plasma progesterone (PP), and fertility (F) in the three predefined seasons. The mating system used was controlled natural nocturnal and lasted for 45 days. Experiment two, evaluated the ram sexual activity. The males (10) were individually exposed to four ovariectomized ewes. The ewes cycled during evaluated seasons, and the highest fertility was observed in animals with BCC >2.75. The PP concentration differed among periods, and higher conception rates (F) were observed in autumn and spring. The rams (75%) had a medium of sexual performance when they performed more than two ejaculations in 20 min throughout the seasons. Pantaneiro sheep of both genders had a similar fertility index, with early and constant activity throughout the year, displaying no photoperiodism or seasonality.


Assuntos
Animais , Comportamento Sexual Animal/fisiologia , Ovinos/fisiologia , Fertilidade/fisiologia , Periodicidade , Brasil
6.
Rev. bras. reprod. anim ; 47(2): 238-243, abr.-jun. 2023.
Artigo em Espanhol | VETINDEX | ID: biblio-1444326

Resumo

A sazonalidade reprodutiva e a condição nutricional são os principais fatores que influenciam o desempenho reprodutivo em ovinos, principalmente em áreas onde a disponibilidade de alimentos é altamente sazonal. A desnutrição pode comprometer a competência folículo-oocitária, a função lútea e o desenvolvimento embrionário. Por outro lado, o tratamento com melatonina é um método eficaz para induzir ciclicidade, aumentando a ovulação e melhorando a viabilidade do embrião durante o anestro. Portanto, levantamos a hipótese de que a melatonina pode substituir os efeitos prejudiciais da desnutrição para melhorar o desempenho reprodutivo em ovelhas. A este respeito, esta revisão enfoca os efeitos da interação entre melatonina e nutrição na viabilidade do embrião e resume a informação disponível sobre o efeito da melatonina exógena na viabilidade do embrião em ovelhas desnutridas.(AU)


Reproductive seasonality and nutritional condition are the main factors that influence reproductive performance in sheep, particularly in the areas where the availability of food is highly seasonal. Undernutrition can compromise follicle-oocyte competence, luteal function and embryo development. On the other hand, melatonin treatment is an effective method for inducing estrous cycles, increasing ovulation and improving embryo viability during anestrus. Therefore, we hypothesized that melatonin can override the detrimental effects of undernutrition to improve reproductive performance in ewes. In this regard, this review focuses on the effects of the interaction between melatonin and nutrition on embryo viability and summarizes the available information about the effect of exogenous melatonin on embryo viability in undernourished ewes.(au)


Assuntos
Animais , Feminino , Ovinos/fisiologia , Desenvolvimento Embrionário , Estações do Ano , Folículo Ovariano/fisiologia
7.
Rev. bras. reprod. anim ; 47(2): 134-139, abr.-jun. 2023.
Artigo em Português | VETINDEX | ID: biblio-1435081

Resumo

A importância dos manejos reprodutivos, que contribui para o avanço da ovinocultura e rentabilidade dos sistemas, revela oportunidades para trabalho com a interação reprodução x produção. Estratégias para incremento produtivo no setor, através de biotécnicas reprodutivas, que permitem redução da idade a puberdade, diminuição da estacionalidade reprodutiva e aumento da taxa ovulatória. Além das possibilidades hormonais, métodos alternativos que consideram efeito macho e nutrição, são considerados eficiente para controle do ciclo. Este artigo tem como objetivo revisar os protocolos de controle do ciclo estral e incremento produtivo na ovinocultura.(AU)


The importance of reproductive management, which contributes to the advancement of sheep farming and the profitability of the systems, reveals opportunities for work with the reproduction x production interaction. Strategies to increase production in the sector, through reproductive biotechniques, which allow reducing the age at puberty, reducing reproductive seasonality and increasing the ovulatory rate. In addition to hormonal possibilities, alternative methods that consider male effect and nutrition are considered efficient for cycle control. This article aims to review the estrous cycle control protocols and productive increase in sheep farming.(AU)


Assuntos
Animais , Ovinos/fisiologia , Fenômenos Reprodutivos Fisiológicos , Taxa de Fecundidade
8.
Rev. bras. reprod. anim ; 47(3): 564-573, jul.-set. 2023. tab
Artigo em Português | VETINDEX | ID: biblio-1436744

Resumo

A bubalinocultura tem expandido mundialmente com grande importância socioeconômica na produção de leite, carne e na tração animal. No entanto, algumas características como: a sazonalidade, poucos reprodutores com genética superior para ser multiplicada e reduzido número de touros com sucesso de coleta constante de sêmen nas Centrais, dificultam a obtenção de maiores índices reprodutivos a nível de Brasil. Neste contexto, a eficiência reprodutiva do rebanho possui papel de destaque, consequentemente, o touro bubalino e a realização do exame andrológico são essenciais para o desenvolvimento da bubalinocultura. Apesar da realização de pesquisas ao longo dos anos relacionadas à andrologia em búfalos, na prática a campo ainda existe uma lacuna referente aos aspectos reprodutivos nessa espécie, fazendo com que haja uma demanda por conhecimento específico. Diante disso, objetivou-se abordar alguns dos principais aspectos da andrologia na espécie bubalina, para auxiliar o Médico Veterinário no atendimento clínico e andrológico visando alcançar uma boa eficiência reprodutiva.(AU)


Buffalo farming has expanded worldwide with great socioeconomic importance in the production of milk, meat and animal traction. However, some characteristics such as: seasonality, few sires with superior genetics to be multiplied and reduced number of bulls with constant semen collection success in the Centrals, make it difficult to obtain higher reproductive rates in Brazil. In this context, the reproductive efficiency of the herd plays a prominent role, consequently, the buffalo bull and the performance of the andrological examination are essential for the development of buffalo breeding. Despite conducting research over the years related to andrology in buffaloes, in field practice there is still a gap regarding reproductive aspects in this species, causing a demand for specific knowledge. In view of this, the objective was to address some of the main aspects of andrology in the buffalo species, to assist the veterinarian in clinical and andrological care in order to achieve good reproductive efficiency.(AU)


Assuntos
Animais , Masculino , Comportamento Sexual Animal , Búfalos/fisiologia , Análise do Sêmen/métodos
9.
Braz. j. biol ; 83: 1-7, 2023. map, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468967

Resumo

In the state of São Paulo, the main sugarcane producing region of the world, two species of scale insects have frequently occurred, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) and Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). To map the distribution and abundance of these species, 17 sugarcane producing fields, distributed in six mesoregions in São Paulo, were evaluated in August 2017 and, January, February, June and July 2018 during the ripening phase. The study on the seasonality of these species, by the presence or absence of the scale insects during the phenological cycle of the plant, was conducted between August 2017 and July 2018 in two sugarcane producing fields in the municipality of Jaboticabal, São Paulo, Brazil. The presence of S. sacchari was found in all the analyzed locations, and A. takahashii in twelve. Both scale insects showed significant difference of infestation in the node’s region of the stems during the ripening phase in one of the studied locations. The aclerdid presented significant difference by infestation in one site during the ripening phase of the plant. The pseudococcid infested a greater number of nodes in the following phases of development; vegetative, grand growth and ripening in both studied areas, but it was in one site during the ripening phase that presented the greatest difference. Although the pink sugarcane mealybug was more abundant than A. takahashii in both studies, there were no patterns of relationships between the numbers of individuals to geographical locations and temperature.


No estado de São Paulo, principal região produtora de cana-de-açúcar do mundo, duas espécies de cochonilhas têm ocorrido frequentemente, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) e Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). Para mapear a distribuição e abundância destas espécies, 17 regiões produtoras de cana-de-açúcar, distribuídas em seis mesorregiões de São Paulo, foram avaliadas em agosto de 2017 e janeiro, fevereiro, junho e julho de 2018, durante a fase de maturação. O estudo da sazonalidade destas espécies, pela presença ou ausência das cochonilhas durante o ciclo fenológico da planta, foi conduzido entre agosto de 2017 e julho de 2018 em duas regiões produtoras de cana-de-açúcar no município de Jaboticabal, São Paulo, Brasil. Saccharicoccus sacchari foi encontrada em todas as localidades analisadas, e A. takahashii em 12. Ambas cochonilhas mostraram diferença significativa de infestação na região dos nós dos colmos durante a fase de maturação em uma das localidades estudadas. O aclerdídeo apresentou diferença significativa pela infestação em uma localidade durante a fase de maturação da planta. O pseudococcídeo infestou um grande número de nós nas seguintes fases de desenvolvimento; perfilhamento, crescimento vegetativo e maturação em ambas áreas estudadas, mas foi em uma localidade durante a fase de maturação que apresentou a maior diferença. Embora a cochonilha rosada da cana-de-açúcar foi mais abundante do que A. takahashii em ambos estudos, não houve padrões de relações entre o número de indivíduos com a localização geográfica e temperatura.


Assuntos
Animais , Demografia/estatística & dados numéricos , Hemípteros/crescimento & desenvolvimento
10.
Braz. J. Biol. ; 83: 1-7, 2023. mapas, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765544

Resumo

In the state of São Paulo, the main sugarcane producing region of the world, two species of scale insects have frequently occurred, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) and Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). To map the distribution and abundance of these species, 17 sugarcane producing fields, distributed in six mesoregions in São Paulo, were evaluated in August 2017 and, January, February, June and July 2018 during the ripening phase. The study on the seasonality of these species, by the presence or absence of the scale insects during the phenological cycle of the plant, was conducted between August 2017 and July 2018 in two sugarcane producing fields in the municipality of Jaboticabal, São Paulo, Brazil. The presence of S. sacchari was found in all the analyzed locations, and A. takahashii in twelve. Both scale insects showed significant difference of infestation in the nodes region of the stems during the ripening phase in one of the studied locations. The aclerdid presented significant difference by infestation in one site during the ripening phase of the plant. The pseudococcid infested a greater number of nodes in the following phases of development; vegetative, grand growth and ripening in both studied areas, but it was in one site during the ripening phase that presented the greatest difference. Although the pink sugarcane mealybug was more abundant than A. takahashii in both studies, there were no patterns of relationships between the numbers of individuals to geographical locations and temperature.(AU)


No estado de São Paulo, principal região produtora de cana-de-açúcar do mundo, duas espécies de cochonilhas têm ocorrido frequentemente, Aclerda takahashii (Kuwana, 1932) (Hemiptera: Aclerdidae) e Saccharicoccus sacchari (Cockerell, 1895) (Hemiptera: Pseudococcidae). Para mapear a distribuição e abundância destas espécies, 17 regiões produtoras de cana-de-açúcar, distribuídas em seis mesorregiões de São Paulo, foram avaliadas em agosto de 2017 e janeiro, fevereiro, junho e julho de 2018, durante a fase de maturação. O estudo da sazonalidade destas espécies, pela presença ou ausência das cochonilhas durante o ciclo fenológico da planta, foi conduzido entre agosto de 2017 e julho de 2018 em duas regiões produtoras de cana-de-açúcar no município de Jaboticabal, São Paulo, Brasil. Saccharicoccus sacchari foi encontrada em todas as localidades analisadas, e A. takahashii em 12. Ambas cochonilhas mostraram diferença significativa de infestação na região dos nós dos colmos durante a fase de maturação em uma das localidades estudadas. O aclerdídeo apresentou diferença significativa pela infestação em uma localidade durante a fase de maturação da planta. O pseudococcídeo infestou um grande número de nós nas seguintes fases de desenvolvimento; perfilhamento, crescimento vegetativo e maturação em ambas áreas estudadas, mas foi em uma localidade durante a fase de maturação que apresentou a maior diferença. Embora a cochonilha rosada da cana-de-açúcar foi mais abundante do que A. takahashii em ambos estudos, não houve padrões de relações entre o número de indivíduos com a localização geográfica e temperatura.(AU)


Assuntos
Animais , Hemípteros/crescimento & desenvolvimento , Demografia/estatística & dados numéricos
11.
Braz. j. biol ; 83: e255758, 2023. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1439625

Resumo

Here, we evaluate the relationships between the infestation rates of five monogenean parasites species with the dry and wet seasons, with the organic and inorganic parameters of the water of two rivers: the Jacaré-Pepira and Jacaré-Guaçú, and with the condition factors of its fish hosts: Serrasalmus maculatus and Astronotus crassipinnis, in the state of São Paulo, southeastern Brazil. Fish were collected between January and December 2017. Anacanthorus serrasalmi, Amphithecium speirocamarotum and Gussevia asota had higher abundance rates (Student's t test, p ≤ 0.05) in the wet season. Gussevia asota had its abundance negatively correlated to nitrate in the Jacaré-Pepira River and with total nitrogen and potassium in the Jacaré-Guaçú River. Regarding the fish hosts condition factors, was observed a positive correlation with the abundances of G. asota in the Jacaré-Guaçú River, and with A. serrasalmi in the Jacaré-Pepira River. In general, wet season favored an increasing in the infestation rates of the monogeneans parasites in their host species, mainly in the river considered as the most polluted, the Jacaré-Guaçú River. Of the five parasites species analyzed in this study, only Gussevia astronoti and Rhinoxenus piranhus had no interaction with seasonality, river water variables, or fish host condition factors. On the other hand, G. asota had interactions both with water parameters (nitrate and total nitrogen) and with the hosts condition factors, which reflected in the abundance and intensity rates, showing itself as a species sensitive to changes in the environment and, therefore, that can be considered as a bioindicator organism.


Aqui, nós avaliamos as relações entre as taxas de infestação de cincos espécies de parasitos monogenéticos em relação aos períodos seco e chuvoso, aos parâmetros orgânicos e inorgânicos da água de dois rios: Jacaré-Pepira e Jacaré-Guaçú, e em relação aos fatores de condição das espécies de peixes hospedeiras: Serrasalmus maculatus e Astronotus crassipinnis, no estado de São Paulo, sudeste do Brasil. Os peixes foram coletados entre os meses de janeiro a dezembro de 2017. Anacanthorus serrasalmi, Amphithecium speirocamarotum e Gussevia asota tiveram maiores taxas de abundância (teste t de Student, p ≤ 0,05) no período chuvoso. Gussevia asota teve sua abundância negativamente correlacionada com o nitrato no rio Jacaré Pepira e com o nitrogênio total e potássio no rio Jacaré-Guaçú. Em relação ao fator de condição dos peixes, foi observado uma correlação positiva com a abundância de G. asota no rio Jacaré-Guaçú e com A. serrasalmi no rio Jacaré-Pepira. No geral, o período chuvoso favoreceu um aumento nas taxas de infestação dos parasitos monogenéticos em seus peixes hospedeiros, especialmente no rio considerado como o mais poluído, o rio Jacaré-Guaçú. Das cinco espécies de parasitos analisadas no estudo, somente Gussevia astronoti e Rhinoxenus piranhus não tiveram nenhum tipo de interação com a sazonalidade, com as variáveis das águas dos rios ou com o fator de condição dos peixes hospedeiros. Por outro lado, G. asota teve interações tanto com os parâmetros da água (nitrato e nitrogênio total) quanto com os fatores de condição dos hospedeiros, que refletiram nas taxas de abundância e de infestação, mostrando que esta espécie é sensível às mudanças no ambiente e que, portanto, pode ser utilizada como um organismo bioindicador.


Assuntos
Animais , Características da Água , Rios , Peixes/parasitologia , Interações Hospedeiro-Parasita
12.
Ciênc. anim. bras. (Impr.) ; 24: 73559P, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1430190

Resumo

The objective of this study was to evaluate the seasonal effect of months of the year upon the physiological and productive responses of crossbred dairy cows raised in an Amazonian climate. Twenty lactating cows were evaluated, fed on Brachiaria decumbens pasture, with free access to water and mineral supplementation. Data from climate variables air temperature (AT), relative humidity (RH), rainfall (RA) and temperature and humidity index (THI) were recorded dur ing the months of January to April 2019. The physiological data collected were: respiratory rate (RR, mov/min), heart rate (HR, beats/min), rectal temperature (RT, ºC), udder surface temperature (UST, ºC), body surface temperature (BST, ºC), dorsum surface temperature (DST, ºC), front surface temperature (FST, ºC) and rear shin temperature (RST). Milk production (MP) was also measured. There was a significant difference (P<0.05) of RST and RR with values ranging from 34.8 to 35.5°C and 32.0 to 36.2 mov/min, respectively. There were no significant difference (P>0.05) for BST, and the values for MP and THI were 3.8; 3.8; 4.6; 4.1 kg and 77.7; 79.7; 80.6; 80.1, respectively. It was concluded that there was a seasonal effect of the months of the year evaluated on the respiratory rate of animals, however, it did not change the MP and the THI. The Amazon environment is conducive to causing thermal stress in lactating cows raised on pasture, requiring the use of shading to facilitate the ability of these animals to dissipate heat.(AU)


O objetivo desse estudo foi avaliar os efeitos sazonais dos meses do ano sobre as respostas fisiológicas e produtivas de vacas leiteiras mestiças criadas em clima amazônico. Foram avaliadas 20 vacas lactantes, alimentadas com pasto de Brachiaria decumbens, com acesso livre a água e suplementação mineral. Foram registrados dados das variáveis climáticas temperatura do ar (TA), umidade relativa do ar (UR), precipitação pluviométrica (PP) e índice de temperatura e Umidade (ITU) durante os meses de janeiro a abril de 2019. Os dados fisiológicos coletados foram: frequência respiratória (FR, mov/min), frequência cardíaca (FC, bat./min), temperatura retal (TR, ºC), temperatura superficial do úbere (TSU, ºC), temperatura superfície corporal (TSC, ºC), temperatura superficial do dorso (TSD, ºC), temperatura superficial da fronte (TSF, ºC) e temperatura superficial da canela (TSCA, °C). Também foi mensurada a produção de leite (PL, kg). Houve diferença significativa (P<0,05) da TSCA e FR com valores variando de 34,8 a 35,5°C e 32,0 a 36,2 mov/min, respectivamente. Não houve diferença significativa (P>0,05) para TSC e os valores observados para PL e ITU foram 3,8; 3,8; 4,6; 4,1 kg e 77,7; 79,7; 80,6; 80,1, respectivamente. Houve efeito sazonal dos meses avaliados sobre a taxa respiratória dos animais, no entanto, isso não alterou a PL nem o ITU. O ambiente amazônico é propício a causar estresse térmico em vacas lactantes mantidas a pasto, sendo necessário o uso de sombreamento para facilitar a capacidade de dissipação de calor corporal desses animais.(AU)


Assuntos
Animais , Feminino , Bovinos/fisiologia , Modalidades Fisiológicas , Estações do Ano , Pastagens , Resposta ao Choque Térmico/fisiologia , Brachiaria
13.
Rev. bras. reprod. anim ; 47(1): 22-31, jan.-mar. 2023. ilus
Artigo em Português | VETINDEX | ID: biblio-1434881

Resumo

Os equinos são animais poliéstricos sazonais, fotoperiódico positivos, apresentando ciclos reprodutivos em estações definidas do ano, primavera e verão, e estações com ausência ou baixa atividade reprodutiva, outono e inverno. A necessidade da maximização do período reprodutivo, bem como a definição de um ano hípico iniciando em julho, no hemisfério sul (para algumas raças como o Puro Sangue de Corrida e o Quarto de milha) levou ao desenvolvimento de técnicas para diminuir o tempo que essas éguas permanecem em anestro reprodutivo. Uma das técnicas mais utilizadas destaca-se o uso de iluminação artificial. Consistindo no fornecimento de luz branca incandescente ou led azul ou branco em baias, piquetes ou por meio de máscaras, a fim de simular os efeitos de dias longos no organismo assim liberar o eixo hipotalâmico-hipofisário-gonadal. Para estimular o retorno antecipado à ciclicidade, a égua deve ser exposta a um estímulo de 14 a 15 horas de luz diárias, totalizando 9 a 10 horas de escuridão, ou receber um estímulo de 1 hora de luz, aproximadamente 9 horas após o anoitecer. É fundamental que a égua esteja com escore corporal adequado e alguns cuidados com o fornecimento da luz artificial sejam atendidos, como a continuidade no fornecimento para o sucesso da técnica.(AU)


Horses are seasonally breeding animals which means that they natural breed in specific seasons (Spring, and Summer), with non or low reproductive activity on the other seasons (Winter and Fall). The development of techniques to shorten the anoestrus can be necessary to anticipate the breeding season, starting in July in the Southern Hemisphere, for some breeds such as Thoroughbred and Quarter Horses. The most common technique is the use of artificial lighting with incandescent, or blue/white led light, applied in stalls, paddocks or with a light mask to mimic the effects of a long day and release the hipotalamic-hipophysarie-gonadal axis. To stimulate an early return to cyclicity, the mare should be exposed to a 14-to-15-hour light stimulus daily, totalling 9 to 10 hours of darkness, or receive a 1-hour light stimulus, approximately 9 hours after dusk. It is fundamental that the mare has an adequate body condition score and some awareness with the provision of artificial light are considered, such as the continuity of the light program for the success of the technique.(AU)


Assuntos
Animais , Feminino , Iluminação/efeitos adversos , Fenômenos Reprodutivos Fisiológicos , Cavalos/fisiologia , Estações do Ano , Fotoperíodo
14.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487514

Resumo

This study aimed to compare the activity of ants during the rainy and dry seasons in a transitional environment (ecotone) at the interface of Cerrado and Caatinga biomes situated in the state of Piauí, where studies of local ant fauna are still incipient. The research was carried out at Floriano, state of Piauí, Brazil. Ants were sampled during the rainy season in December 2018 and during the dry season in June 2019. Three parallel transects were established at least 100 m apart. At each point, three sampling methods were used, with attractive baits placed on the trees and ground, and pitfall traps on the ground. Thirty-one ant species belonging to 14 genera and five subfamilies were collected, with 27 recorded in the rainy season and 17 in the dry season. The only species reported with the three collection methods and the two seasons was Camponotus crassus Mayr, 1862. Seven ant species sampled in this study are new reports for the state of Piauí. There was a significant difference in the average number of ants and the composition of the assemblages between the rainy and dry seasons. We demonstrate that the activity of ants is influenced by seasonality, corroborating our hypotheses. This is only the second study on ant diversity in the state of Piauí, and more studies are necessary to understand the processes and factors which regulate the activity patterns of ants in ecotonal

15.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1487518

Resumo

Abstract This study aimed to compare the activity of ants during the rainy and dry seasons in a transitional environment (ecotone) at the interface of Cerrado and Caatinga biomes situated in the state of Piauí, where studies of local ant fauna are still incipient. The research was carried out at Floriano, state of Piauí, Brazil. Ants were sampled during the rainy season in December 2018 and during the dry season in June 2019. Three parallel transects were established at least 100 m apart. At each point, three sampling methods were used, with attractive baits placed on the trees and ground, and pitfall traps on the ground. Thirty-one ant species belonging to 14 genera and five subfamilies were collected, with 27 recorded in the rainy season and 17 in the dry season. The only species reported with the three collection methods and the two seasons was Camponotus crassus Mayr, 1862. Seven ant species sampled in this study are new reports for the state of Piauí. There was a significant difference in the average number of ants and the composition of the assemblages between the rainy and dry seasons. We demonstrate that the activity of ants is influenced by seasonality, corroborating our hypotheses. This is only the second study on ant diversity in the state of Piauí, and more studies are necessary to understand the processes and factors which regulate the activity patterns of ants in ecotonal situations like those observed in this region.

16.
Sci. agric. ; 79(2)2022.
Artigo em Inglês | VETINDEX | ID: vti-762544

Resumo

ABSTRACT: Appropriate management of factors that influence forest development is essential to increase yield of forest plantations. The objective of this study was to evaluate the influence of water seasonality, nutritional management, and uniformity on yield of eucalyptus plantations and estimate the potential, attainable, and observed yield of adult eucalyptus stands. We evaluated Eucalyptus clonal stands in six regions of Minas Gerais State, Brazil, in a system of first and second rotation across four age classes using the twin-plots method (TP). In the study, 142 TPs were allocated alongside 142 plots in a continuous forest inventory (CFI) network of a private enterprise. The CFI received operational fertilization and additional fertilization was carried out in the TP. The trees were measured at the beginning of the experiment and at every six months to quantify the production in the wet (PW) and dry (PD) periods of the year. Uniformity of plantations was evaluated using Pvar 50 % and the optimal uniformity index. Potential, attainable, and observed yields were estimated using the average annual increase at seven years of age. The PW showed higher plant yield. There was an effect due to water availability and nutrient level on the yield of the stands. The driest semester of the year produces approximately 30 % of the current annual increase. The stands under the second rotation tend to have less uniformity than the in the first rotation. Potential yield varied depending on rainfall intensity where wetter regions had the highest yield.

17.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1460001

Resumo

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.


This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well as cattle performance in alternate stocking from three tropical forage cultivars. The experiment followed a randomized block design, in a 3 x 3 factorial scheme with three replications. Three forage cultivars (Marandu, Massai and Xaraés) distributed in nine hectares were evaluated in three dry season periods (transition wet/dry, dry, and end of dry season), with repeated measures over time. The following variables were evaluated: canopy height, leaf: stem ratio, forage mass, leaf mass, stem mass and dead material mass. Total digestible nutrients, crude protein and in vitro dry mass digestibility were evaluated regarding forage nutrition. Animal performance, using 36 eleven-month-old animals (half-blood Nelore), was evaluated by the daily average gain and weight gain by area. During pre-grazing, canopy height presented interaction among forage cultivars and the evaluated periods. The average daily gain showed no interaction among cultivars and period of the year the similarity in animal performance among the cultivars Marandu and Massai show that the Massai grass can be used as an alternative for forage diversification under an alternate management system.

18.
Anim. Reprod. (Online) ; 19(1): e20200050, 2022. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1360102

Resumo

Abstract This study aimed to evaluate the effect of synchronization with prostaglandin F2α in Baixadeiro mares during the rainy and dry seasons. Fourteen mares were synchronized by administering two doses of 1 mL prostaglandin PGF 2α and monitored by rectal palpation and ultrasound for the assessment of follicular development and uterine echotexture. Of this total, nine mares allowed the collection of blood, in which the blood was collected by venipuncture of the jugular vein to determine progesterone (P4) by ELISA. Mares showed no differences (P > 0.05) in weight, body score condition (BSC), tone, uterine edema, frequency of ovulation, synchronization interval, estrus, and the total number of follicles between periods. However, there was a difference in large increased follicle diameter (P < 0.05) during the dry season. The average concentrations of P4 in mares differed (P < 0.05) between the pre- and post-ovulatory phases for both seasons and after ovulation, with higher concentrations in the rainy season. Furthermore, statistical differences in daily light (P < 0.05) were observed between the dry and rainy periods. Thus, we conclude that mares from the genetic grouping Baixadeiro showed no reproductive seasonality, though there was a difference in luminosity between the rainy and dry seasons. The treatment with two doses of PGF 2α was effective in synchronizing the mares, promoting the return of estrus in the dry and rainy periods. The mares remaining cyclically active throughout the year provided there were appropriate forage availability and quality levels to allow for normal values of body weight and condition.

19.
Iheringia, Sér. zool ; 112: e2022020, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1405115

Resumo

Seasonality in the Cerrado biome of Brazil is characterized by a dry season and a rainy season, affecting the availability of water and generating nutritional limitations. Thus, plants and animals have developed adaptive mechanisms in order to survive in this environment. Insects known as antlions (Neuroptera: Myrmeleontidae) occur in areas of the Cerrado and build traps in dry soil to capture prey items. In the rainy season, these insects are unable to forage due to the waterlogged soil. The aim of this study was to investigate the influence of the rainfall regime in the Cerrado on aspects of trap-building behavior, larval development and morphological characteristics of adult antlions. Larvae of the antlion Myrmeleon brasiliensis (Návas, 1914) were observed and collected in an area of the Cerrado biome in the municipality of Aquidauana (MS), Brazil. Observations were performed in the rainy and dry seasons to determine the abundance of traps built by M. brasiliensis larvae. In the laboratory, experiments were performed involving the manipulation of the frequency of simulated rain on the traps. The results revealed that variations in rainfall due to seasonality in the Cerrado affect M. brasiliensis larvae, with greater foraging observed in the dry season. The laboratory experiments demonstrated that differences in the frequency of rains affect the mortality of the larvae, larval development time and the size of the adults. Thus, variations in rainfall patterns can lead to variations in the characteristics of the population structure of M. brasiliensis in areas of the Cerrado biome in Brazil.


No bioma Cerrado a sazonalidade (caracterizada por uma estação seca e outra chuvosa) afeta a disponibilidade de água e produz limitações nutricionais, de maneira que várias plantas e animais desenvolveram mecanismos adaptativos elaborados para sobreviver nesse ambiente. Insetos conhecidos como formiga-leão ocorrem em áreas de Cerrado e constroem suas armadilhas de captura de presas no solo seco. No período chuvoso as larvas ficam impedidas de forragear, dado o encharcamento do solo. Este trabalho tem como objetivo compreender a influência do regime de chuvas do Cerrado em aspectos do comportamento de construção da armadilha, no desenvolvimento das larvas e nas características morfológicas dos adultos. Larvas de formiga-leão Myrmeleon brasiliensis (Návas, 1914) foram observadas e coletadas em uma área de Cerrado no município de Aquidauana (MS), Brasil. Para verificar a abundância das armadilhas das larvas de M. brasiliensis foram realizadas observações no período chuvoso e seco. No laboratório foram realizados experimentos de manipulação da frequência de chuva nas armadilhas de M. brasiliensis. Como resultado foi observado que variações na sazonalidade do Cerrado afetam as larvas de M. brasiliensis, as quais são observadas forrageando em maior abundância na estação seca. Os experimentos de laboratório demonstraram que variações na frequência da chuva podem afetar, a mortalidade das larvas, o tempo de desenvolvimento das mesmas, o tamanho das armadilhas e o tamanho dos adultos. Sendo assim, variações no padrão de incidência de chuvas podem levar a variações nas características da estrutura da população de M. brasiliensis em áreas de Cerrado.


Assuntos
Animais , Formigas/anatomia & histologia , Estações do Ano , Caça , Larva/crescimento & desenvolvimento , Chuva , Brasil , Pradaria
20.
Sci. agric ; 79(02): 1-11, 2022. map, tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1498029

Resumo

Appropriate management of factors that influence forest development is essential to increase yield of forest plantations. The objective of this study was to evaluate the influence of water seasonality, nutritional management, and uniformity on yield of eucalyptus plantations and estimate the potential, attainable, and observed yield of adult eucalyptus stands. We evaluated Eucalyptus clonal stands in six regions of Minas Gerais State, Brazil, in a system of first and second rotation across four age classes using the twin-plots method (TP). In the study, 142 TPs were allocated alongside 142 plots in a continuous forest inventory (CFI) network of a private enterprise. The CFI received operational fertilization and additional fertilization was carried out in the TP. The trees were measured at the beginning of the experiment and at every six months to quantify the production in the wet (PW) and dry (PD) periods of the year. Uniformity of plantations was evaluated using Pvar 50 % and the optimal uniformity index. Potential, attainable, and observed yields were estimated using the average annual increase at seven years of age. The PW showed higher plant yield. There was an effect due to water availability and nutrient level on the yield of the stands. The driest semester of the year produces approximately 30 % of the current annual increase. The stands under the second rotation tend to have less uniformity than the in the first rotation. Potential yield varied depending on rainfall intensity where wetter regions had the highest yield.


Assuntos
Agricultura Florestal/métodos , Chuva , Eucalyptus/crescimento & desenvolvimento , Secas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA