Uso da geoestatística na avaliação de variáveis ambientais em galpão de suínos criados em sistema "wean to finish" na fase de terminação

Abstract

RESUMO:O "wean to finish" é um sistema de criação de suínos que ainda é novo no Brasil, e não existem muitos estudos a respeito do ambiente onde estes animais são criados. Assim, o objetivo deste trabalho foi avaliar o ambiente térmico e aéreo por meio da técnica da geoestatística em galpão de suínos criados no sistema "wean to finish", na fase de terminação, nos horários das 09h, 12h e 15h. A variabilidade dos atributos foi baseada na estatística descritiva dos dados de temperatura, umidade relativa, velocidade do ar, concentrações de amônia e dióxido de carbono, obtendo-se: média, mediana, coeficiente de variação, assimetria e curtose, com o teste de normalidade de Kolmogorov-Smirnov, através do programa estatístico Minitab 15. Para a determinação da existência ou não da dependência espacial, utilizou-se do exame de semivariograma, através do programa GS + , e, na elaboração dos mapas de distribuição espacial das variáveis, foi utilizado o programa Surfer. Os atributos de velocidade do ar e as concentrações dos gases NH3 e CO2 apresentaram alto coeficiente de variação devido aos dados serem heterogêneos, pois a instalação apresentava ventilação natural. O uso dos mapas de krigagem permitiu observar a diferença espacial da distribuição das variáveis avaliadas com diferentes números de animais/baia e em diferentes horários. PALAVRAS-CHAVE: ambiência, distribuição espacial, mapas, suínos. USING GEOSTATISTICS TO EVALUATE THE ENVIRONMENT OF "WEAN TO FINISH"SWINE HOUSING ABSTRACT:The "wean to finish" is a new pig production system in Brazil. To date, few research have investigated the environmental conditions of this pig farming system. The aim of this study was to evaluated the thermal environmental conditions and gases concentration using geostatistical techniques of a wean-to-finish barn during finishing phase at 9AM, 12PM e 3PM. The data variability was evaluated by the descriptive analysis, of the temperatures, relative humidity, air velocity, ammonia and carbon dioxide concentration. The results showed the average, median, coefficient of variation, asymmetry and curtosis and the Kolmogorov-Smirnov Test with the software Minitab 15. To determine the spatial dependence, the semivariogram exam was done, with the software GS + . The air velocity and gases concentration showed the highest coefficient of variation. This has happened because of the heterogeneity of the data caused by the natural ventilation. The Krigging maps showed the spacial differences of the pens with different numbers of animals in different hour of the day.

Zoning of environmental conditions inside a wean-to-finish pig facility

“…Therefore, these variables are inversely proportional, a finding that was also emphasized by CARVALHO et al (2012) andMEDEIROS et al (2014). Moreover, RH remained within limits postulated in the literature only in the upper left region, emphasizing existing microclimates within this facility; furthermore, factors like air temperature, shadowing, stocking density, water consumption and wasting could interfere with this variable.…”

“…MEDEIROS et al (2014), studying the thermal environment for pigs reared in a wean-to-finish system, at different stock densities and at F phase, found a RH value of 40.44% at 3 pm, which is within the bearable range. Therefore, the found RH values highlight the evaporative cooling potential of the facility (CARVALHO et al, 2009), being advisable the installation of nebulizers and fans inside the barn to assist in heat loss.…”

“…The variability of the attributes was verified based on descriptive statistics of the data recorded (Tdb, RH, Sair, CO2 and NH3), The variability of the attributes has been verified based on descriptive statistics data recorded, obtaining means, medians, coefficients of variation and the normality by Kolmogorov-Smirnov's test, as describe in MEDEIROS et al (2014). The spatial dependence is given by semivariogram fitting (VIEIRA, 2000), based on stationarity of the intrinsic hypothesis, which is estimated by [eq.…”

“…In contrast, in wean-to-finish systems, animal flow is held within the same facility from weaning to slaughter (MEDEIROS et al, 2014). Nevertheless, studies on environmental quality, weight gain, sexing, and animal welfare for this system are still scarce.…”

“…Thus, spatial variability maps could disclose that analyzing a single point might be not enough, under-or over-estimating such value (SILVA et al, 2013;NÄÄS, 2011). Several authors have reported the use of geostatistics in animal husbandry MEDEIROS et al, 2014;SILVA NETO et al, 2011). Given the above, this study aimed to identify different environmental zones within a pig rearing facility of a wean-tofinish system during growing to finishing and finishing phases, by making use of geostatistics.…”