Feed Efficiency and Physiological Parameters of Holstein and Crossbred Holstein × Simmental Cows.

This study aimed to compare the feed efficiency (FE) and physiological parameters of Holstein and crossbred Holstein × Simmental cows in a confinement system during winter and summer. The study was conducted in a dairy farm in southern Brazil by including a total of 48 multiparous cows. The cows were studied for 21 days in two periods, summer and winter, and their daily dry matter intake (DMI), milk yield (MY), rectal temperature (RT), respiratory rate (RR), body weight, and body condition score were recorded. An analysis of variance was conducted using the SAS statistical package. The results showed that crossbred Holstein × Simmental cows have a similar FE as Holstein cows in a high-production system (1.83 × 1.81 kg DMI/kg MY, respectively), and they can achieve the same production levels as purebred Holstein cows (43.8 vs. 44.5 milk/cow/day). Our findings indicated a difference for the period as both genetic groups achieved higher FE in winter than in summer (1.98 vs. 1.67 DMI/kg MY, respectively). In addition, we found evidence that crossbred cows are better at dissipating body heat during heat-stress situations, as they have higher RR in summer compared to purebred cows, while Holstein cows have higher RT in summer afternoons than crossbred cows. Therefore, using crossbred Holstein × Simmental cows is an alternative for high-production systems.

Deois flexuosa (Hemiptera: Cercopidae) in Perennial Forage Species (Poaceae): Quali-quantitative Impacts and Tolerance Expression.

This study aimed to characterize the quantitative and qualitative damage caused by Deois flexuosa (Walker) (Hemiptera: Cercopidae) adults in Axonopus catharinensis cv. SCS 315 Catarina and Cynodon dactylon (Tifton 85 and Jiggs cultivars) under different infestation densities and, consequently, the expression of tolerance-type resistance. For this purpose, potted plants were infested with different insect densities (0, 5, 10, 20, and 40 adults m-2). The impact of the infestation levels was assessed in the first growth cycle (10-day coexistence period) and in the regrowth (40 days after the first cut, without infestation) based on crop yield and chemical-bromatological composition as well as on photosynthetic pigments and hydrogen peroxide content. The principal component analysis relating infestation density and chemical-bromatological parameters showed a positive correlation between infestation density of D. flexuosa and the contents of neutral detergent fiber, acid detergent fiber, and the dry matter (DM). On the other hand, infestation density inversely correlated with the tillering rate, photosynthetic pigments (chlorophyll a and b, carotenoids), and iron content. In general, the impacts on DM production and chemical-bromatological composition were lower in A. catharinensis cv. SCS 315 Catarina when compared to the Cynodon species, possibly because A. catharinensis has higher tillering capacity and does not show a reduction in the photosynthetic pigments, which may act as compensating factors to D. flexuosa damage. Our results demonstrate that the A. catharinensis cultivar expresses tolerance-type resistance to D. flexuosa and constitutes an interesting option for pasturelands formation and diversification where this spittlebug species is an emerging pest.

Potentially toxic metals of vegetable gardens of urban schools in Lages, Santa Catarina, Brazil / Metais potencialmentetóxicos em hortas escolares na região urbana de Lages, Santa Catarina, Brasil

ABSTRACT: Urban environments are contaminated in many ways with persistent organic and inorganic pollutants as a result of anthropogenic activities, endangering human health and natural resources. The objective of the present study was to evaluate the soil contamination by cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in 10 vegetable gardens of urban schools located near or on Botucatu sandstone outcrops of Guarani Aquifer in the urban areas of Lages, Santa Catarina, Brazil. In each garden, three soil samples at each position (in the soil immediately outside and the soil in the garden) were collected at a depth of 0-20 cm. The ISO 11466 method was used to extract the metals. Inductively coupled plasma optical emission spectrometry was used to quantify the elements and certified materials to evaluate the quantities (SRM 2709a - San Joaquin Soil - NIST). To evaluate the data, principal component analyses and cluster analyses were performed. The cluster analysis for the evaluated metals showed that the highest contents of elements were reported in three gardens. Values above the prevention value defined by resolution no. 420/2005 of the National Council for the Environment -Conselho Nacional do Meio Ambiente (CONAMA) - were reported for cobalt in one garden and copper in three gardens; thus, these areas were categorized as Class III areas. Principal component analysis explained 74.7% of the data and showed the enrichment of some elements within gardens.

RESUMO: Ambientes urbanos são contaminados de muitas maneiras com poluentes orgânicos e inorgânicos persistentes como resultado de atividades antrópicas, colocando em risco a saúde humana e os recursos naturais. O objetivo do presente estudo foi avaliar a contaminação do solo por cobalto (Co), cromo (Cr), cobre (Cu), manganês (Mn), níquel (Ni), chumbo (Pb) e zinco (Zn) em 10 hortas de escolas urbanas situadas próximo ou sobre áreas de afloramento de arenito Botucatu do Aquífero Guarani, no município de Lages, Santa Catarina. Em cada horta, três amostras de solo foram coletadas (dentro e fora da horta) na profundidade de 0-20 cm. O método ISO 11466 foi usado para extrair os metais. Utilizou-se espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES) para quantificar os elementos e materiais certificados (SRM 2709a - San Joaquin Soil - NIST). Para avaliar os dados foi feita a análise dos componentes principais e análise de agrupamento. Pela análise de agrupamento para os metais avaliados observou-se que as maiores concentrações de elementos foram encontradas em três hortas. Valores acima do valor de prevenção (PV) definido pela resolução no. 420/2005 do Conselho Nacional do Meio Ambiente (CONAMA) foram encontrados para Co em uma horta e Cu em três hortas, classificando essas áreas como classe III. A análise de componentes principais explicou 74,7% dos dados e mostrou o enriquecimento de alguns elementos dentro das hortas.