Non-structural carbohydrates in the nutrition of high-yielding dairy cows during a transition period

Abstract

The main aim of this study was to investigate experimentally the effect of different composition of non-structural carbohydrates (NFC) in prepartum feed rations administered to high-yielding dairy cows at a high concentration of NFC in the diet on dry matter intake both before and after parturition and on subsequent milk performance, body condition and physiological traits of rumen fluid and blood. Thirty-six high-yielding dairy cows were allocated into one of the three well-balanced groups (K, O, and C), and each group received a different feeding rations. Feeding rations differed in non-structural carbohydrate (NFC) structure. The "K" (control) group received a feeding ration with NFC in the form of maize starch in particular, while the feeding rations of the other two (experimental) groups contained either (besides maize starch) saccharose from dried sugar beet (the "O" group) or a dominant amount of NFC was in the form of saccharose (the "C" group). After calving, all dairy cows were given the same feeding ration from the first day after parturition. The experiment was conducted for 21 days before and 50 days after calving. FR in the form of total mixed ration was offered ad libitum. Dry matter intake, milk performance, body condition, live weight, and blood and rumen parameters were recorded for the duration of the experiment. Average daily dry matter intake before calving was highest in the "K" group (14.32 kg per head). Differences among groups were statistically significant (P < 0.05). Prepartum dry matter consumption dropped as the rate of saccharose in the diet of cows increased. Dry matter consumption levelled off after calving. Milk yield was also highest in the "K" group (43.71 kg/head/day), but fatness of milk and thus the production of fat corrected milk were lowest in this group. The highest milk fat content (4.10%) and fat corrected milk production (44.03 kg/head/day) were recorded in the "C" group, whereas the highest milk protein concentration was found in the milk of the "O" group. The composition of NFC affected dry matter intake before parturition, but these concentrations did not significantly affect dry matter intake, milk yield, milk composition, live weight, body condition or blood serum and rumen fluid parameters after calving

Effect of the type of non-fibre carbohydrates in grass silage-based diets on in sacco ruminal degradability and protein value of lupin (Lupinus angustifolius L. cv. Sonet) seeds ground to different particle sizes

“…Th e replacement of maize starch with sucrose in the silage-based diet contributed to a reduction in the ruminal concentration of ammonia and excretion of urinary urea-N and urinary total N (Broderick et al, 2008). Th is dependence is in line with the results reported by Poláková et al (2010), who found out that the increased supplementation of sugars from 25% to 44% of NFC in place of starch in rations administered to high-yielding dairy cows decreased the urea concentration in blood serum from 4.7 to 3.9 mmol/l as a result of better utilization of nitrogen substances in the rumen. It seems that the more intensive degradation of lupin seed DM and CP takes place in the rumen conditions resulting from the better synchronization of energy availability for microbial metabolism, which is associated with the introduction of dietary sucrose in place of starch.…”

Lipid and lipoprotein profile changes in dairy cows in response to late pregnancy and the early postpartum period

“…In dairy cows pregnancy is recognized as inducing remarkable physiological and metabolic adaptations essential to ensure the suitable development of the foetus and to provide adequate substrates that are needed in utero and following birth (Modina et al, 2007;Van Dorland et al, 2009;Polakova et al, 2010).…”

Effects of season and time of milking on spontaneous and induced lipolysis in bovine milk fat

“…Milk fat is one of the principal milk solids, and its content considerably changes throughout the entire lactation period and also during a single day (Poláková et al 2010). Milk fat consists of triacylglycerol, phospholipids, non-esterified fatty acids, and glycerol.…”

“…FFA) into the bloodstream (Nelson & Cox 2000). Thus, the concentration of NEFA may reach a value detrimental to the health status of cows both prepartum (Poláková et al 2010) and postpartum (Herdt 2007). A wide range of dairy cows' production diseases are treated using antibiotics which affect the final quality of raw milk as well (Navrátilová et al 2011).…”