Manipulating dry cow diets to ensure consistency in feed intake across the transition period

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Dairy producers are continually challenged with ensuring consistent feed intake in their cows as they transition from the dry period to lactation, to reduce post-partum diseases and promote production. Cows that succumb to one or more metabolic diseases after calving are at higher risk of low milk production, reduced reproductive performance, increased risk of other disease, and lower efficiency of production, and thus are less profitable. Subclinical ketosis (SCK), related to low feed intake during this time period, is one health condition that impacts many cows, with an estimated incidence of >40%. Similarly, subacute ruminal acidosis (SARA), often related to imbalanced nutrient intake (possibly due to feed sorting) impacts up to 30% of lactating cows, with highest incidence in early lactation. A potential method of improving intake, both in terms of amount and consistency (i.e. reduced sorting) across the transition period would be to make the dry and fresh cow rations appear similar, in physical composition. The objective of this research is to determine if pre-calving feed intake can be improved, feed sorting can be discouraged, as well as consistency in intake maintained after calving, by feeding dry cow diets that more closely resemble lactating cow diets in terms of physical characteristics. In two studies we will test cost-effective methods of making dry cow rations more similar in physical resemblance to lactating diets, specifically by changing forage (straw) particle length and through the addition of water. We predict that these ration modifications will not only reduce sorting and improve intake during the dry period, but carry over to improve nutrient intake and energy balance in early lactation. From these results, improvements in health, welfare, and efficiency of dairy cows will not only allow Canadian dairy producers to be more profitable, but also increase consumer confidence in this agricultural sector.