Effect of changes in diet energy density on feed intake, milk yield and metabolic parameters in dairy cows in early lactation

Self Cite

The present experiment examined the effect of offering either a high-(H) or low-(L) energy-density diet in late gestation and early lactation on physiological parameters, body condition score (BCS) and milk production in early lactation. In all, 40 multiparous Holstein cows were randomly allocated to one of four treatments in a 2 3 2 factorial design, where the factors were H-or L-energy density in a total mixed ration (TMR) both pre-and post-calving. Consequently, there were four treatment groups: HH, HL, LL and LH. The pre-calving treatment was initiated 100 days prior to expected calving; the H TMR was fed ad libitum whereas the L TMR was restricted to 10 kg dry matter/day during late lactation, and to approximately 75% of energy requirements from drying off until calving. Both diets were offered ad libitum post-calving. Feeding diet H compared to L precalving led to higher BCS at calving (2.68 v. 2.34, P , 0.01). Energy corrected milk yield and energy-intake post-calving were not affected by pre-calving diets. Changes in BCS and blood concentrations of non-esterified fatty acids, beta-hydroxybutyrate and glucose in early lactation showed that cows offered diet H pre-calving generally mobilised more body reserves compared to cows offered diet L pre-calving. An interaction between pre-and post-calving diets showed that cows offered diet H pre-calving had lower body tissue mobilisation when offered diet H post-calving compared to diet L. Cows offered diet L pre-calving, did not mobilise differently whether they were offered diet H or L post-calving. The pre-and post-calving diets had no effect on liver triacylglycerol, whereas liver glycogen was higher in cows on treatment HH compared to the other three treatments. Collectively, these results indicate that overfeeding should be avoided in late gestation and that a high-energy-density diet is desirable in early lactation in order to obtain a more favourable metabolic profile.

Section: Effect Of Diet On Post-calving Measuressupporting

confidence: 53%

Energy intake in late gestation affects blood metabolites in early lactation independently of milk production in dairy cows

Nielsen

Hameleers²,

Young

et al. 2010

Self Cite

“…The only effect on milk production during P2 was that of the severe (SS and MS cows) or moderate (SM and MM cows) treatment imposed during that period. The absence of a carryover effect on milk yield following feed restriction in early lactation has previously been described in short- (Nielsen et al, 2007) and long-term studies (Friggens et al, 1998;Delaby et al, 2009). Kennedy et al (2007), Roche (2007) and Kay et al (2011) reported a carryover effect on milk yield, but its duration was limited (,2 months) partly because the intensity of restriction at pasture remained moderate (PGSH of 3.1 to 5.2 cm).…”

Section: Effect Of Pgsh In Early Lactationmentioning

confidence: 75%

Direct and carryover effect of post-grazing sward height on total lactation dairy cow performance

Ganche

Delaby

O’Donovan

et al. 2013

Grazing pastures to low post-grazing sward heights (PGSH) is a strategy to maximise the quantity of grazed grass in the diet of dairy cows within temperate grass-based systems. Within Irish spring-calving systems, it was hypothesised that grazing swards to very low PGSH would increase herbage availability during early lactation but would reduce dairy cow performance, the effect of which would persist in subsequent lactation performance when compared with cows grazing to a higher PGSH. Seventy-two Holstein-Friesian dairy cows (mean calving date, 12 February) were randomly assigned post-calving across two PGSH treatments (n 5 36): 2.7 cm (severe; S1) and 3.5 cm (moderate; M1), which were applied from 10 February to 18 April (period 1; P1). This was followed by a carryover period (period 2; P2) during which cows were randomly reassigned within their P1 treatment across two further PGSH (n 5 18): 3.5 cm (severe, SS and MS) and 4.5 cm (moderate, SM and MM) until 30 October. Decreasing PGSH from 3.5 to 2.7 cm significantly decreased milk (22.3 kg/cow per day), protein (295 g/day), fat (2143 g/day) and lactose (2109 g/day) yields, milk protein (21.2 g/kg) and fat (22.2 g/kg) concentrations and grass dry matter intake (GDMI; 21.7 kg dry matter/cow per day). The severe PGSH was associated with a lower bodyweight (BW) at the end of P1. There was no carryover effect of P1 PGSH on subsequent milk or milk solids yields in P2, but PGSH had a significant carryover effect on milk fat and lactose concentrations. Animals severely restricted at pasture in early spring had a higher BW and slightly higher body condition score in later lactation when compared with M1 animals. During P2, increasing PGSH from 3.5 to 4.5 cm increased milk and milk solids yield as a result of greater GDMI and resulted in higher mean BW and end BW. This study indicates that following a 10-week period of feed restriction, subsequent dairy cow cumulative milk production is unaffected. However, the substantial loss in milk solid yield that occurred during the period of restriction is not recovered.

“…The absence of any delayed effect on milk yield due to feed management at the beginning of lactation, and the weak persistence of its influence on protein and fat content, has already been described in short-term (Nielsen et al, 2007) and longer-term trials (Coulon et al, 1996;Friggens et al, 1998). In certain trials (Kennedy et al, 2007;Roche, 2007), the authors describe a significant carryover effect on milk and fat yield, but its persistence is actually rather limited (1 to 2 months).…”

Section: Discussionmentioning

confidence: 87%

Effect of different feeding strategies on lactation performance of Holstein and Normande dairy cows

Delaby

Faverdin

Michel

et al. 2009

The dairy farming systems of Western Europe are based on a simple feeding system composed of grazed and preserved grass, maize silage and concentrates in variable proportions. There is, nevertheless, a great diversity of feeding strategies between dairy farms. Over 5 years, we studied the direct and delayed effects of four feeding strategies on the lactation and reproduction performances of Holstein and Normande dairy cows. The four feeding strategies (denoted Hh, Hl, Lh and Ll) correspond to two total mixed rations applied in winter from calving to turnout (maize silage with 30% concentrate or grass silage with 15% concentrate), which were subsequently crossed with two levels of concentrate supplementation at grazing to 210 days. Each year, 72 dairy cows managed in grouped winter calving were assigned to the four strategies. Finally, the results of 325 lactations and 295 inseminated cows were analysed. The four strategies resulted in considerable variation in nutrient intake and, in particular, in differences in concentrates consumed, with values of 1407, 1026, 773 and 392 kg dry matter per cow for strategies Hh, Lh, Hl and Ll, respectively. Total milk production (7567, 7015, 6720 and 6238 kg per cow for treatments Hh, Lh, Hl and Ll, respectively), milk fat content (39.0, 37.1, 40.3 and 38.5 g/kg, respectively), milk protein content (33.0, 31.8, 33.1 and 31.6 g/kg, respectively), and the character of the lactation and body condition curves were all highly sensitive to the strategies applied. While no significant interaction was detected on total lactation yield, the Holstein cows reacted more dramatically to each dietary change at each period, compared with the Normande cows. Winter feeding did not affect the production of milk at pasture whereas, at pasture, the milk from the cows of the H groups in winter was higher in milk fat and protein content. Reproduction performance was unaffected by feeding strategy. The Holstein cows, well fed and producing the most milk (Hh and Hb), had the lowest rate of success at first artificial inseminations (21.5%). The dual-purpose Normande cows had a pregnancy rate 10 points higher than Holstein cows. This comparison of strongly contrasting feeding strategies confirms the immediate reactivity of dairy cows (in terms of milk performance and body condition) to variations of nutritive intake throughout lactation, with a weak carryover effect from feeding levels early in lactation. In contrast, reproduction performance was less sensitive to variation in nutrient supply. Keywords: dairy cows, feeding strategy, lactation, reproduction, breed ImplicationsThe main objective of this 5-year experiment was to describe the dairy cows' ability to adapt their lactation and reproductive functions to different feeding strategies applied during lactation. These original results provide practical information on breed, feeding system effects and their interaction, and will help advisors and farmers to choose the most efficient systems according to the economic circumstances. IntroductionIn Fra...