Effects of early lactation concentrate level and glucogenic feed on feed intake, milk production and energy metabolism in dairy cows and heifers

Abstract

In order to examine the effect of two levels of concentrate and the effect of glucogenic feed (0 1/d (GO) or 1 1/d (Gl)) 16 multiparous and 16 primiparous Friesian cows were used in a factorial 2x2 design. The concentrate levels for multiparous cows were 11 kg/d (CI 1) and 15 kg/d (CI 5) and for primiparous cows 9 kg/d (C9) and 12 kg/d (CI2). The glucogenic feed consisted of propylene glycol, polyols, molasses and niacin. All the animals were offered wilted silage ad libitum. The experimental period started from calving and lasted for 12 weeks.Multiparous cows substituted concentrate for silage when glucogenic feed was not given whereas with glucogenic feed the effect of concentrate on silage dry matter intake (DMI) was minor. Glucogenic feed had a minor effect on milk production at the higher level of concentrate and a negative effect on milk production at the lower level of concentrate. Due to this interaction the milk yield response to the higher level of concentrate was higher with glucogenic feed. The low rumen degradable protein supply in C11G1 was probably the cause of these interactions.The milk production response of primiparous cows to the higher level of concentrate was low. After peak yield the plasma insulin concentrations were higher with the higher concentrate level. This was accompanied by higher liveweight gain.In conclusion, the response of multiparous cows to higher concentrate level depended on the supply of rumen degradable protein, whereas the comparable response of primiparous cows was * Financial support by the Agricultural Research Foundation of August Johannes and Aino Tiura 564 GLUCOGENIC FEED FOR COWS limited by milk yield potential and the needs of growth. The glucogenic feed showed an ability to increase plasma glucose and decrease the concentrations of ketones.

Effect of Concentrate Crude Protein Level on Grass Silage Intake, Milk Yield and Nutrient Utilisation by Dairy Cows in Early Lactation

“…Jugular vein blood samples were taken one week before the expected calving day, and 1, 4 and 8 weeks after calving, before the afternoon feeding at 13:00, for the determination of ␤-hydroxybutyrate (BHB), acetoacetate, glucose, insulin, glucagon and non-esterified fatty acids (NEFA), as described by Kokkonen et al (2000b). Urea (Gutman and Bergmeyer, 1974) and total protein (Weichselbaum, 1946) were determined from plasma.…”

“…Furthermore, many of these experiments have commenced 1 to 3 weeks after calving. Our previous early lactation study (Kokkonen et al, 2000b) showed the potential of multiparous cows to increase milk yield with increased concentrate level, when crude protein content of grass silage was low. We have also shown, that rapeseed meal supplementation during late gestation may stimulate voluntary feed intake postpartum (Tesfa et al, 2001).…”

Effect of the rate of increase in concentrate allowance with concentrates high or low in starch on the performance of dairy cows in early lactation

“…Faverdin et al (1991) measured a mean substitution rate of 0.61 between silage and concentrate in mid-lactation for grass silage-based diets. The substitution rate during the first weeks of lactation has been documented only in a few papers and the results have been variable (Kokkonen et al, 2000;Ingvartsen et al, 2001). …”

“…In their study, the amount of concentrate varied between 3.5 and 10.2 kg/day. In early lactation studies there have been considerable variation in the measured substitution rate (Kokkonen et al, 2000;Ingvartsen et al, 2001). In a study by Kokkonen et al (2000), the substitution rate varied from 0.88 to 0.03 for multiparous cows, and for primiparous cows even the silage intake increased with increased concentrate intake during days 1 to 42 of lactation.…”

“…In early lactation studies there have been considerable variation in the measured substitution rate (Kokkonen et al, 2000;Ingvartsen et al, 2001). In a study by Kokkonen et al (2000), the substitution rate varied from 0.88 to 0.03 for multiparous cows, and for primiparous cows even the silage intake increased with increased concentrate intake during days 1 to 42 of lactation. Ingvartsen et al (2001) measured a very high substitution rate (0.94) during the first weeks of lactation when the rate of increase in concentrate allowance changed from 0.3 to 0.5 kg/day.…”