ABSTRACT. The objective was to evaluate the morphometric, productive and chemical aspects of purple elephant grass as a function of nitrogen fertilization. The treatments consisted of applying 0, 20, 40, 60, and 80 kg ha-1 of N, using a randomized block design, with five treatments and four replications. The following were evaluated: plant height, number, length and leaf mass, stem diameter and mass, leaf/stem ratio, production of green and dry mass, support capacity for dairy cows, crude protein, neutral detergent fiber and mineral matter. The data were submitted to analysis of variance and Tukey's test at 5% probability. The increase in N doses did not affect (p < 0.05) the morphometry of the purple elephant grass, however it positively stimulated the productivity, the animal support capacity and the bromatological components of the harvested material. The lack of response to nitrogen fertilization may be related to the edaphocilimatic conditions during the experiment and efficiency in the use of N of the variety used. The results demonstrate the high demand of the cultivar for N, actively interfering in the forage yield.

ABSTRACT. The objective of this study was to evaluate the use of sorghum silage, Buffel grass hay and forage palm fodder in the diet of dairy goats by means of performance tests and economic viability of different roughage sources. Eight Anglo-Nubian goats, multiparous, weighing around 40.13 ± 2.76 kg of live weight were used. The experiment lasted 84 days, consisting of four periods of 21 days, distributed in two Latin squares (4x4). The treatments represented by diets with different volumetric sources: SSCF: (sorghum silage+ forage palm+ concentrate); BHCF: (Buffel grass hay + cactus forage+ concentrate); SS: (sorghum silage+ concentrate) and BH: (Buffel grass hay + concentrate). Nutritional intake, digestibility, feed behavior, milk production and chemical composition and economic analysis were evaluated. Animals fed the BHCF diet had higher nutrient intakes and consequently were more productive in fat, protein, lactose, fat free solids and total solids. The BHCF diet led to a higher gross income in Brazilian currency. The safety margin of the SSCF diet presented the highest percentage, with 43.06%, and the BHCF diet, the lowest percentage, of 14.89. The association of forage palm with sorghum silage and Buffel grass hay can be used as a bulky source in lactating goat diets.

ABSTRACT. The objective of this study was to evaluate the use of multinutritional blocks (BMs) associated with the concentrate content in the diet of lactating goats and their effects on milk production and economic viability. Eight goats Parda Alpina, multiparas were distributed in two Latin squares (4x4). The experiment consisted of four treatments (0.971, 0.746, 0.521 and 0.296 kg concentrate day-1 per goat) and BMs ad libitum. It was evaluated the consumption, milk monitoring and the system was analyzed economically. If there was a significant effect of the concentrate, the control treatment was compared to the others using the Dunnett test and 5% regression analysis. When the concentrate contents were high in the diets, the total dry matter intake decreased linearly. However, there was an inverse behavior for the consumption of BMs. Milk production (PL kg day-1) was linear and positively related to the increase of concentrate levels in the diets. The PL was lower for the decreasing levels of concentrate when compared to the control diet. The economic parameters indicate that the use of low concentrate levels associated with BMs is the best feeding strategy for lactating goats. The multinutritional blocks can be used to feed lactating goats to partially replace the concentrate.