Utilização de concentrado e milho em grão na alimentação de vacas leiteiras em sistemas de produção da região do Arenito Caiuá, Paraná, Brasil

Abstract

The use of grains for animal feed has increased its importance in milk production. As major producers and exporters, Brazil and Paraná State have great availability of grains with the possibility of being converted into milk, adding value to the grain. Furthermore, considering the market and the institutional changes promoted there was an increase of foods consumption, including dairy products, stimulating domestic milk production. The milk production chain is important in the Brazilian agribusiness by socioeconomic aspects, having large production base to increase. In this work, the overall goal is to identify productive variables that enable the employment growth of maize in the diet of dairy cows as well as the identification of groups of producers who use corn in different forms. For this, besides the general introduction, two articles were written. At first, the objective was to determine the productive factors related to the use of grain in milk production. For this, it was made a literature review about the chains of maize, milk and the use of corn grain in feed. Multivariate analysis was performed with 16 variables originated from data collected in 185 dairy farmers in the region of Colorado, PR. From the variables, it was used the technique of exploratory factor analysis, which resulted in the formation of two main components - one the indicator of herd characteristics and other the indicator of grain use. Considering this factors there were defined four groups from the technique of cluster analysis. In converting grain into milk, Groups 4 and 1 were defined as enhancers, and Groups 2 and 3 as reducers. For the second article, the proposed objective was to identify productive factors associated with increased use of concentrated and maize grain in dairy cows feed. In this study, was made literature review about maize and milk chain, and employment of maize grain in animal feeds. Data were collected through semi-structured questionnaires applied to 185 dairy farmers in the region of Colorado, PR. Considering two variables related with the use of maize and concentrated in animal feed, four groups were defined using cluster analyses. After that, comparison of means (ANOVA) were made between the four groups defined and productive variables. As a result, for the variables: milk production, number of cows in milk, production/animal and the total herd of cows, Groups 1 and 2 did not differ significantly (P>0.05), as well as Groups 3 and 4. However Groups 1 and 2 had best values for productive variables when compared with Groups 3 and 4. The use of concentrated got best results than the use of maize grain to increase the production rates.