Measurement of cognitive bias and cortisol levels to evaluate the effects of space restriction on captive collared peccary (Mammalia, Tayassuidae)

We use the judgement-bias paradigm to evaluate whether space restriction in metabolism pens affects the emotional state of collared peccary (Pecari tajacu) during a nutritional experiment. We trained individual adult males to ‘go’ to a specific location within 30 s when a positive auditory cue (whistle; CS+) was given in order to receive cassava root pieces as a reward, and to ‘no-go’ when a negative cue (caxixi percussion instrument; CS−) was sounded to avoid punishment (jet of water) and no reward. An ‘ambiguous’ auditory cue (a drumstick hitting an aluminum plate; CSA) was presented to probe decision-making under ambiguity. Individuals were subjected to five 8-day housing conditions in the order: H1 (control-no space restriction-metabolism pen and additional area), H2 space restriction without environmental enrichment (metabolism pen only), H3 (control-no space restriction), H4 (space restriction with environmental enrichment), and H5 (control-no space restriction). On the eighth day of each housing condition, each animal was exposed to 10 judgement bias trials of each of the three cue types: CS+, CS−, and CSA. We recorded whether animals showed the ‘go’ or ‘no-go’ response after each type of cue and collected fecal samples to assess fecal glucocorticoid metabolite concentrations. Peccaries learnt to discriminate CS+ and CS− and maintained this discrimination during the five housing conditions tested. The response to the ambiguous cue (CSA) varied according to the housing condition. During H1, the peccaries made a similar proportion of ‘go’ responses to all three types of cue (Ps > 0.07). During H2 and H3, ‘go’ responses to CSA and CS− cues occurred in similar proportions (Ps > 0.70), but peccaries showed more go responses to CS+ (Ps < 0.03) indicating that they were responding to CSA as if it were more likely to predict the waterjet than food. During H4 and H5, peccaries again made a similar proportion of ‘go’ responses to all three types of cue, as in H1. During H2 and H3, fecal glucocorticoid metabolite concentrations were higher than during the other tests (208.0 ± 16.4 vs. 141.6 ± 25.9 ngg−1 dry feces, Ps < 0.03). Our results suggest that space restriction may induce physiological stress and influence judgement bias and affective state in peccaries, and that these effects may be offset by environmental enrichment. However, the possibility of a general habituation to the housing conditions across time cannot be ruled out

EFICIÊNCIA DO INSETICIDA PRODAFENTION NO CONTROLE DO BICHO-MINEIRO DO CAFEEIRO Perileucoptera coffeella (GUÉRIN-MÉNEVILLE, 1842) (LEPIDOPTERAl: LYONETIIDAE) EM CONDIÇÕES DE CAMPO

Avaliou-se a eficiência do inseticida pridafention, nas formulações concentrado emulsionável e pó molhável, visando controle do bicho-mineiro, Perileucoptera coffeella (Guérin-méneville, 1842) (Lep: Lyonetiidade) do cafeeiro. Comparou-se os resultados aos oito e quinze dias após aplicação, com os inseticidas padrões dimetoato e deltametrina. O pridafetion apresentou níveis de controle semelhantes aos de dimetoato e superiores aos de deltametrina

Phenotypic stability of hybrids of Gália melon in Rio Grande do Norte state, Brazil

The objectives of this study were to determine the importance of simple and complex components of the interaction genotype × environment and to evaluate the adaptability and stability of Gália melon hybrids. Nine hybrids were tested in twelve environments of Rio Grande Norte State from 2000 to 2001. The experiments were carried out in a randomized complete block design with three replications. The statistical methods of Toler and Burrows, Wricke and AMMI (Additive Main effect and Multiplicative Interaction) were used to study the adaptability and stability. The complex component is responsible for most of the genotype × environment interaction for the yield and content of solids soluble of fruits. The environments associated with Mossoró and Assu municipalities are the most suitable to evaluate melon hybrids in the state. The hybrid DRG 1537 was the most likely to be grown in the Agro-industrial Complex Mossoró-Assu due to its stability, high productivity and high content of soluble solids.<br>Os objetivos deste estudo foram determinar a importância das componentes simples e complexa da interação genótipo × ambiente e avaliar a adaptabilidade e estabilidade de híbridos de melão Gália. Nove híbridos foram testados em doze ambientes do Estado do Rio Grande Norte no período de 2000 a2001. Os experimentos foram conduzidos em blocos completos casualizados com três repetições. Os métodos estatísticos de Toler e Burrows, Wricke e AMMI (Additive Main effect and Multiplicative Interaction) foram usados para estudar a adaptabilidade e estabilidade. A componente complexa é responsável pela maior parte da interação genótipo × ambiente para a produtividade e teor de sólidos solúveis dos frutos. Os ambientes associados com Mossoró e Assu são os mais adequados para a avaliação de melão híbrido. O híbrido DRG1537 é o mais promissor para o cultivo no Complexo Agro-industrial Mossoró-Assu, devido à sua estabilidade, alta produtividade e alto teor de sólidos solúveis

Hydraulic conductivity of a soil irrigated with treated sewage effluent

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