A comparison of individual cow versus group concentrate allocation strategies on dry matter intake, milk production, tissue changes, and fertility of Holstein-Friesian cows offered a grass silage diet

Abstract

A diverse range of concentrate allocation strategies are adopted on dairy farms. The objectives of this study were to examine the effects on cow performance [dry matter (DM) intake (DMI), milk yield and composition, body tissue changes, and fertility] of adopting 2 contrasting concentrate allocation strategies over the first 140 d of lactation. Seventy-seven Holstein-Friesian dairy cows were allocated to 1 of 2 concentrate allocation strategies at calving, namely group or individual cow. Cows on the group strategy were offered a mixed ration comprising grass silage and concentrates in a 50:50 ratio on a DM basis. Cows on the individual cow strategy were offered a basal mixed ration comprising grass silage and concentrates (the latter included in the mix to achieve a mean intake of 6kg/cow per day), which was formulated to meet the cow's energy requirements for maintenance plus 24kg of milk/cow per day. Additional concentrates were offered via an out-of-parlor feeding system, with the amount offered adjusted weekly based on each individual cow's milk yield during the previous week. In addition, all cows received a small quantity of straw in the mixed ration part of the diet (approximately 0.3kg/cow per day), plus 0.5kg of concentrate twice daily in the milking parlor. Mean concentrate intakes over the study period were similar with each of the 2 allocation strategies (11.5 and 11.7kg of DM/cow per day for group and individual cow, respectively), although the pattern of intake with each treatment differed over time. Concentrate allocation strategy had no effect on either milk yield (39.3 and 38.0kg/d for group and individual cow, respectively), milk composition, or milk constituent yield. The milk yield response curves with each treatment were largely aligned with the concentrate DMI curves. Cows on the individual cow treatment had a greater range of concentrate DMI and milk yields than those on the group treatment. With the exception of a tendency for cows on the individual cow treatment to lose more body weight to nadir than cows on the group treatment, concentrate allocation strategy had little effect on either body weight or body condition score over the experimental period. Cows on the individual cow treatment had a higher pregnancy rate to first and second service and tended to have a higher 100-d in calf rate than cows on the group treatment. This study demonstrates that concentrate allocation strategy had little effect on overall production performance.

Effects of an individual cow concentrate strategy on production and behavior

“…Moreover, only 1% of the cows ate more than 7.5 kg of DM/d in concentrates even though the maximum limit of concentrate allowance was 8.6 kg of DM/d. Total DMI did not differ between the 2 concentrate strategies, supporting previous studies where concentrate allocation was based on the level of individual yield or energy balance (Maltz et al, 2013;Little et al, 2016;Purcell et al, 2016). However, the individual cow concentrate strategy increased the concentrate intake by 1 kg during mid lactation and 0.7 kg during late lactation compared with the control strategy for both breeds.…”

“…However, other studies showed that milk production did not improve for cows fed an individual cow concentrate strategy based on weekly milk yield compared with either a PMR with a fixed amount of concentrate or a group strategy with TMR feeding (Little et al, 2016;Purcell et al, 2016). In contrast, an individual cow concentrate strategy based on the calculated energy balance and applied as a TMR to Holstein cows in early lactation improved milk production compared with a standard TMR (Maltz et al, 2013).…”

Pre- and postpartum effects of starch and fat in dairy cows: A review

“…Supporting this response, previous studies reported enhanced milk production as a result of increased energy intake (Erickson et al, 1992;Chouinard et al, 1997;Moallem et al, 2000). However, other studies reported no effect on milk yield when feeding enriched starch-or fat-based diets or combinations (Garnsworthy et al, 2008b;Gilmore et al, 2011;Little et al, 2016). These researchers suggested that the lack of a significant effect on milk production could be attributed to the use of isocaloric diets in the studies.…”

“…However, important enhancements in conception rates were observed when feeding a diet that increased glucose and insulin levels in the early postpartum period and then switching to a diet that reduced insulin levels during the mating period, compared with other treatments (Garnsworthy et al, 2009). Furthermore, pregnancy rates for first and second services were enhanced when grass silage was supplemented with a similar concentrate fed to cows individually, based on the milk yield of the previous week, compared with those on a mixed diet containing grass silage and concentrate in a 50/50 ratio on a DM basis (Little et al, 2016). In contrast, Gilmore et al (2011) found no improvements in pregnancy rates when feeding a glucogenic diet in early lactation to encourage the resumption of oestrus followed by a lipogenic diet to promote embryonic development, compared with other treatments.…”

“…Manipulating the energy level and source in the diet of pre-and postpartum cows showed significant improvements in terms of decreased incidence of health problems (Beever, 2006), optimized rumen microbial activity (Jouany, 2006), increased amount of digested nutrients from the gastro-intestinal tract (GIT) (Bauman & Currie, 1980), decreased body condition loss (Drehmann, 2000;Butler, 2003), and increased milk responses (Grum et al, 1996;Ingvartsen & Andersen, 2000;Cavestany et al, 2009a;Reis et al, 2012;Damgaard et al, 2013;Roche et al, 2013;Hills et al, 2015). However, studies on the pre-and postpartum effects of starch-or fat-based diets on dairy cow reproduction parameters are contradictory, with some studies reporting a negative effect or lack of effect of it (Beam & Butler, 1997;Oldick et al, 1997;Oldick et al, 1998;McNamara et al, 2003;Van Knegsel et al, 2007c;Dyck et al, 2011;Gilmore et al, 2011), compared with other studies that reported a positive effect (Gong et al, 2002;Cavestany et al, 2009b;Garnsworthy et al, 2009;Reis et al, 2012;Little et al, 2016;Thatcher, 2017). The objectives of this review are therefore to discuss the effects of energy-based diets containing starch and/or fat during the dry and postpartum periods on the subsequent metabolism, milk production and fertility of dairy cows.…”