Editor’s note: The following answer is from a presentation at the Cornell Nutrition Conference by Rick Grant, director of the William H. Miner Agricultural Research Institute in Chazy, N.Y., and Tom Tylutki, CEO of Agricultural Modeling and Training Systems in Cortland, N.Y.

Q: Will greater feeding frequency necessarily result in improved dry matter intake?

A: DeVries and von Keyserlingk (2005) concluded that delivery of fresh feed was the most important stimulus for dairy cows to eat compared with feed push-up and return of cows from the milking parlor. Consequently, frequency of feed delivery should be a primary factor to consider for improving prediction of DMI. Delivery of fresh TMR stimulates eating activity.

Feed push-up is secondarily important, and pushing up feed is more important during the day rather than at night (DeVries et al., 2005).

The management goal is to ensure adequate feed accessibility throughout the day because limited feed access often encourages more aggressive interactions at the feed bunk, greater eating rate, and may limit DMI (Grant and Albright, 2001) ...

However, Mantysaari et al. (2006) compared once versus five times daily feeding of TMR and observed an increase in eating time, but a reduction in DMI with greater feeding frequency. Energy-corrected milk yield was unaffected, so gross efficiency of milk production was improved. However, lying time was reduced by nearly 15 percent with greater feeding frequency ...

Although greater feeding frequency of TMR often increases eating time, the effect on DMI has been variable and often negative.

Interestingly, in most studies where resting time was negatively impacted by greater feeding frequency, improvements in eating time did not result in greater DMI. It may be that increased feeding frequency improves DMI only if it does not negatively affect lying behavior.

Resting and feeding behavior are linked

Lying behavior has a high priority for cattle after even relatively short periods of lying deprivation (Munksgaard et al., 2005). Cows will sacrifice feeding in an effort to recoup lost resting time. Consequently, environmental factors that interfere with resting may also reduce feeding behavior.

Metz (1985) evaluated cow response when access to either resting stalls or the feed manger was prohibited. Cows attempted to maintain a fixed amount of lying time, and their well-being was impaired when lying time was restricted for several hours daily. An additional 1.5 h/d standing time was associated with a 45-min reduction in feeding time.

A similar relationship was observed by Batchelder (2000) where cows experiencing a stocking density of 130 percent of stalls and headlocks preferred lying in free stalls rather than eating post-milking and spent more time in the alley waiting to lie down rather than eating.

A review of published studies indicates that, for rest deprivation ranging between 2 and 4 h/d, there was a 30 to 58 percent compensation following the rest deprivation. The associated reduction in eating time has ranged between 32 and 45 min/d (Metz, 1985; Hopster et al., 2002; Cooper et al., 2007). Lying-deprived cows had reduced time spent eating during the actual period of lying deprivation as well as after the deprivation.

From the data in these papers, it appears that cows sacrifice approximately 1 min of eating time for each 3.5 min of lost rest. If this relationship represents a long-term, chronic behavioral adaptation to environments that restrict resting time, then we need to adjust expected eating time and its predicted effect on DMI.