Evaluation of Nitrogen Sources on Ingestive Ethology and Production in Gir Cows. / AvaliaÃÃo de fontes nitrogenadas na etologia ingestiva e desempenho de vacas Gir leiteiras.
AUTOR(ES)
Thiago Alves Prado
DATA DE PUBLICAÇÃO
2006
RESUMO
The objective of this study was to promote a comparative study of four diets containing Urea, Amirea150S (two levels) or neither one, on intake, milk production and quality and intake behavior of penned Gir cows. This trial was conducted at the EPAMIG experimental station in Uberaba-MG. Twenty multiparous and primiparous Gir cows received corn silage and concentrates as follows: FS â only soybean meal as the protein source; UR â 3.0 % urea; AM1 â 5.4 % amirea; AM2 8.1%. Animals were housed in individual pens. A randomized block design was used where four blocks were formed to control previous cow milk production. Dry matter intake (DMI) was greater (p<0.05) for AM1 (160.68 g/kg PV0.75) and AM2 (153.93 g/kg PV0.75) compared to UR (128.22 g/kg PV0.75). However DMI was smaller (p<0.05) for FS (12.7 kg/d), AM1 (12.4 kg/d) and AM2 (12.7 kg/d) compared to UR (9.4 kg/d). Total milk solid production was greater (p<0.05) for FS (1734 g/d), AM1 (1745 g/d) and AM2 (1727 g/d) compared to UR (1297 g/d). Mild fat was greater (p<0.05) for AM1 (5.2%) compared to FS (4.1%) and AM2 (4.5%), but did not differ (p>0.05) from UR (4.7%). Milk urea was greater (p<0.05) for AM2 (13.3 mg/dL) compared to FS (10.6 mg/dL), but it did not differ (p>0.05) form UR (11.9 mg/dL) and AM1 (11.5 mg/dL). It is concluded that the inclusion of Amirea 150S on the diet of Gir cows was able to increase DMI and milk production, including milk solids, compared to current urea based diets.
ASSUNTO(S)
amirÃia 150s, urÃia, nitrogÃnio nÃo protÃico, lactaÃÃo, rumen. amirÃia 150s, urÃia, non protein nitrogen, lactation, rumen. zootecnia
