Metabolism and ruminal parameters of Holstein × Gir heifers fed sugarcane and increasing levels of crude protein

Abstract

-The objective of this study was to evaluate the effect of increasing levels of crude protein (CP) in the diet (13, 15, 19 and 22 g/100 g of dry matter, DM) on the metabolism and ruminal parameters of crossbred heifers fed forage sugarcane. Four crossbred Holstein × Gir heifers of average initial weight of 200 kg and average age of 14 months were used. The experimental design was in a 4 × 4 latin square. The intake values of DM, organic matter (OM), neutral detergent fiber (NDF) and non-fibrous carbohydrates (NFC) were not affected by the protein contents of the diet. The apparent and ruminal digestibility of DM and OM were affected by the protein content of the diet. Greater total apparent digestibility coefficient of CP (0.749) was observed for the content of 22 g CP/100 g DM, whereas the ruminal digestibility of CP was not affected by treatments. The efficiency of microbial protein synthesis was not different between the CP contents of the diet. There was increasing linear effect of the CP content in the diet on the plasma concentration of urea. The rumen pH of the heifers was similar between treatments, with an average of 6.3. The concentration of rumen ammonia nitrogen was affected by the protein content of the diet, with the highest averages at 22 and 19 CP/100 g DM (27.5 and 31.6 mg/dL); an average of 21.1 mg/dL in the diet with 15 g CP/100 g DM; and the lowest average observed in the diet containing 13 g CP/100 g DM, 14.0 mg/dL. It is recommended to use 13 g CP/100 g DM in the diet for crossbred Holstein × Gir heifers in the post-weaning phase consuming diets based on sugarcane, because this level promotes increase in the digestibility of the diet and lower concentrations of plasma urea nitrogen and ammonia nitrogen, showing better animal metabolism, in addition to a possible decrease in the cost of the diet.

<b>Nutrient intake, productive performance and body measurements of dairy heifers fed with different sources of protein</b> - doi: 10.4025/actascianimsci.v35i3.18749

“…These values are above the estimated for the feed formulation used, which estimated average intakes of diets at 2.36% body The results obtained in this study were higher than found by Queiroz et al (2012) that obtained means of 4.8 kg dry matter per day and 2.1% for BW for diet composed of 70% forage and 30% concentrate, on a dry matter basis, which contained 13 % crude protein, using sugar cane as forage for feeding dairy heifers, Holstein x Gir, with averaging 250 ± 50 kg of body weight and 19 months of age.…”

“…Soybean meal is the protein concentrate commonly used in dairy farming for being a feedstuff of proven high nutritional quality. Nevertheless, there is a growing interest from producers in information about alternative feeds, which can partially or totally replace the traditional ones, bringing reduction in the cost with feeding, as a consequence (QUEIROZ et al, 2012). Another important point to be checked during the growth of heifers is the body development.…”

<b>Multiple supplements containing spineless cactus enriched with urea forcattle

“…The establishment of an efficient management of rearing females is the basis of any dairy production system, with significant participation in production costs (Queiroz, Berchielli, Signoretti, Ribeiro, & Morais, 2012). Tropical pastures are the main source of nutrients for this category of the animal due to the low cost and high convenience.…”

Fatty acid profile, meat quality, and carcass traits of Nellore young bulls fed different sources of forage in high-concentrate diets with crude glycerin

“…These diets subsequently affect ruminal biohydrogenation that could be an influence on fatty acid flow to the duodenum, and thus interfere with fatty acid muscle deposition (Scollan et al, 2014). Among the options for ruminant feed in Brazil, sugar cane and sugar cane bagasse have higher availability, and lower cost per unit of DM (Santos et al, 2011) compared with corn silage; however, they have nutritional limitations, such as a higher level of iNDF (Ezequiel et al, 2006;Queiroz et al, 2012).…”