Missouri Dairy Business Update

Volume 13, Number 4
April 2013

MU Southwest Center Grazing Dairy - Update

SW Center Parlor
By Dr. Stacey Hamilton, University of Missouri Extension

The MU Southwest Center Pasture Dairy is in its 14th year of operation. Many things have changed since its beginning where its objective was to demonstrate a 60 cow family farm efficiently utilizing pasture for its main forage.

This dairy is a seasonal operation where all cows freshen in February-March and are dried off around December 15. The focus of the dairy now is to conduct peer reviewed applied research which can be beneficial to Missouri producers.

Currently the dairy is milking 91 cows with the majority of the cows being U.S. Holstein-Jersey crosses. Approximately 30% of the herd has New Zealand genetics influence. Data is being collected to determine differences in milk production, fertility and efficiency between the U.S. and New Zealand cattle. At this date it is too soon to make any conclusions on any of these parameters as the dairy is just beginning to milk heifers with 75% or greater New Zealand influence.

Current milk production has been 60-63 pounds of milk/cow/day for the last couple of weeks with an average percent of 4.2 and 3.1 for butterfat and protein, respectively. Average days in milk is 72 days with a mean calving date of February 8.

Cows are grazing annual ryegrass, cereal rye and BarOptima +E34 tall fescue with an expected pasture intake of 25-30 pounds of dry matter pasture. Pasture is being supplemented with 10-11 pounds of grain in the parlor. The farm is roughly 60% permanent forages (fescue) and 40% summer/winter annuals (annual ryegrass, cereal rye and crabgrass).

Research Projects

Residual Feed Intake: Three years ago, yearling dairy heifers were fed through the Gro-Safe system to determine their feed efficiency compared to growth. These animals are now being monitored quarterly to determine their efficiency as lactating cows on pasture. Heifers will continue to be fed through the Gro-Safe system as we collect data. The goal will be to select highly efficient and inefficient cows for the milking herd. These cows will be genotyped and efforts made to determine if a genetic marker can be isolated that can be used to select future sires.

Milk Replacer Trial: For the past two years, baby heifer calves have been fed either a traditional milk replacer and weaned at 8 weeks or an accelerated milk replacer and weaned at 6 weeks. These calves are weighed weekly until weaning and then monthly until yearlings to determine growth and average daily gain. Previous research from other universities suggests calves fed the accelerated milk replacer will produce more milk in their first lactation compared to heifers fed a more traditional diet. These studies have been conducted on mostly large framed Holsteins in confinement systems. The objective in this trial is to determine if milk production is impacted on smaller type cattle in pasture systems.

Fescue Variety Trial: Eight varieties of fescue were established last fall. Each variety is replicated four times in a 30 ft by 40 ft plot. Cows will be fitted GPS collars and allowed to select which variety they prefer in each replicate. Varieties will be measured for annual yield, persistence and nutritive value. This trial should commence this fall and will give producers information on what variety may fit their operation. This trial is also being conducted at the MU Forage Systems Research Center with beef cattle.

Fescue Milk Production Trial: The dairy will soon be in a pasture shortage when this trial is started this spring. The entire grazing platform will be destroyed using a spray-smother-spray technique. All existing forage will be replaced with Red River Crabgrass as the summer smother crop. In September, two varieties of fescue will be established to compare annual yield, dry matter intake, milk production and persistence. BarOptima +E34 and a new experimental tall fescue will be compared. Cows will be randomized with half the herd grazing BarOptima +E34 and the remaining grazing the experimental variety. We expected this trial to be conducted for 2-3 years with data starting to be collected in the spring of 2014.

Synchronization Trials:  Three years ago, two synchronization protocols were compared to determine which program would fit systems that employ very tight calving windows. A timed artificial insemination  program (14dCIDR TAI) was compared to a synchronization that used PGF2a and visual heat detection before breeding.

Analyses showed an initial advantage for 14dCIDR_TAI [more cows inseminated and more pregnancies achieved early in the breeding season] that was not maintained over time. Conclusions were that the 14dCIDR_TAI program achieved acceptable FSCR (48%) and overall AI pregnancy rates (64%) but did not surpass a control program that employed AI after observed estrus (61 and 70%; respectively) in a 31 day breeding season.

This year, two separate timed breeding protocols will be compared. The first treatment will be the same as 14dCIDR TAI while the other will utilize a 7 day CIDR rather than the 14 day. Additionally, half of the cows in each treatment will be set up for a resynchronization  of timed breeding at 28 days post breeding from the original timed insemination. If this is successful, this would mean producers would only have to breed cows two days on a group of cows rather than having to detect heat and breed for the entire breeding season.

More information on each of these trials will be provided  but in the essence of space, this gives a brief overview of some of the projects occurring the SW Center dairy.

Back to Missouri Dairy Business Update Index