The objective was to estimate the probability of dairy cows producing milk with fat and protein levels above the percentages desired by the industry, as well as the main factors that influence these levels. Milk samples of 78 first-lactation cows from 29 rural properties in the Planalto Norte Catarinense region were analyzed individually. The reference values for the analysis of fat and protein content were 4.0% and 3.3%, respectively. Logistic regression was used for analysis of the variables and the parameters were evaluated using odds ratios. Breed, age, gestation length, and grazing time are the variables that most influence the probability of producing milk with a protein content above 3.3%. Increasing milk production reduces the probability of obtaining milk with a fat content that allows the maximum bonus. Improvements in the cow's body condition increase the probability of obtaining milk with a fat content that meets the industry's requirements for maximum bonus.

The objective of this study was to evaluate the likelihood of factors inherent to the animal and food to increase the feeding time of dairy cows during the day. For this purpose, we evaluated all articles published in Brazil from 2000 to 2018, retrieved through SciELO and Google Scholars. The following search term was used: "ingestive behavior of dairy cows". Thirty-four articles were retrieved. Articles reporting the genetic group and/or breed of the animals, cow weight, intake data, and bromatological characteristics of the diet were included in the database. After this screening, nine articles were selected. The variables were analyzed by logistic regression using the LOGISTIC procedure available in SAS. The parameters were evaluated using odds ratios, in which the change in the likelihood of longer feeding time was estimated from the function of unit increases in the regressive variables. The percentage of European breeds and NDF intake increased with increasing body weight and there was an increase in the likelihood of longer feeding time. Dry matter intake has an inverse effect on feeding time; the time cows spend feeding decreases as intake increases. Feeding time is influenced by characteristics related to the animal and diet. Keywordsingestive behavior, intake, logistic regression, NDF, odds ratio.Pal avras -ch ave comportamento ingestivo, consumo, FDN, razão de chances, regressão logística.