Source: Manitoba Agriculture, Food and Rural Initiatives
Extended grazing allows livestock to return most of the nutrients they consume directly to the landscape where they are fed. Feed costs can be less but yardage and feeding costs are lower as are manure removal costs. Manure and feed residues contain valuable nutrients that become available to annual or perennial crops. This improves crop productivity and quality, and can extend the grazing season. Extended grazing options can vary from using crop residues to corn, swath, bale or stockpiled perennial forage grazing. Feeding management needs to be flexible to allow for some supplementation or complete feeding in
Perennial forage that is grazed or cut early in the season, with regrowth saved for late-season to early spring grazing, is referred to as stockpiled forage. The first or second cut is harvested as hay and re-growth is grazed after or close to killing frost. Grass and legume mixtures are better suited than pure grass and legume stands for decreased risk of bloat and grasses retain their leaves better.
Alfalfa and grass can be grazed moderately in the fall close to or after a killing frost with minimal impact on the winter survival of the alfalfa. Second cut alfalfa harvested in mid-October averages 15 to 17 per cent protein and 64 to 66 per cent TDN (energy). A dry cow in mid gestation requires TDN in the mid 50s and 7 to 8 per cent protein, while a lactating cow requires TDN in the low 60s and 10 to 11 per cent protein.
Annuals for fall grazing or swath grazing
Annual crops can be swathed in late summer to early fall, and grazed immediately or left until after freeze up. Most annual cereals should be cut at the early to mid-dough stage for highest quality and yield. Control access to the swaths by strip grazing using portable electric fence to reduce the risk of grain overload and ensure higher utilization. Swath grazing during wet falls should be done after freeze up to improve utilization and to decrease waste. Stubble grazing can utilize uncropped areas, straw aftermath and volunteer re-growth that is high quality. An annual crop producing two to three ton dry matter/acre will produce 113 to 168 cow grazing days/acre for a 1300 lb. cow assuming 20 per cent waste or residue.
Grazing standing corn produced 305 cow grazing days per acre (1300 lb. cow)
at the Manitoba Beef and Forage Initiatives Brookdale site from 2016 to 2020.
The average yield was 5.4 ton of dry matter per acre, the protein was 7.3 per cent
protein and the TDN was 73.4 per cent. For either corn or bale grazing, moving
cattle every three to four days using electric fencing minimizes waste and required
labour. Feeding forages prior to moving the cattle to fresh corn will help prevent
grain overload as the cattle won’t be as hungry. Plus tame forages (alfalfa and
grass) will boost the protein in the ration and encourage the cattle to clean up the
Bale grazing can involve all the bales being placed in the fall or hauled every
seven to 10 days during the winter. If the bales are all placed in the fall, electric
cross fencing helps to control feeding and minimizes waste. Another option is
to place the bales in existing paddocks and move the cattle between paddocks
according to how long the feed lasts. Bales should be spaced 30 to 40 feet apart
to allow adequate access for the feeding animals and to keep nutrient importing
at a moderate level. A bale spacing of 33 feet apart equates to 40 bales per acre.
Portable wind breaks provide movable, affordable on-pasture shelter but may not
be adequate in extreme winter conditions with high wind chill. Since snow is a
good insulator a powerful electric fencer is necessary for optimal livestock control.
Using multiple wires including a ground on the cross fence maybe required.
Feed contains valuable nutrients
When producers bale graze, unroll bales, shred bales or feed in rings, nutrients
are being added to the land from the feed being fed. Livestock only capture a
small per cent of these nutrients (10 to 20 per cent) so most of the nutrients are
returned to the land. If 30 bales are fed per acre and the animal utilizes 20 per
cent of the nutrients, 570 lb. of N, 51 lb. of P (117 lb. P2O5) and 434 lb. of K is
returned to the land.
Grazing stockpiled forage in the fall is one of the most economical methods
of extended grazing (fencing and standing forage cost included). Over the last
two years at MBFI, grazing the second cut was the most economical method of
extended grazing at $1.05/cow/day, ($1 in 2019) followed by corn at $1.68 ($1.63),
swath at $2.18 ($2.71) and bale at $2.71 ($3.16). This includes yardage, labor and
supplemented feed. This compares to Manitoba agriculture’s average traditional
feeding cost of $3.57/cow in 2020/21 and $4.23 the year earlier.
By extending the grazing season instead of confining animals and using stored
feed, you can significantly lower winter feeding costs. Some extended grazing
options can cut your feed costs, but not always. Extended grazing returns
nutrients back to the land, it reduces manure disposal costs and it cuts winter
feeding and yardage costs. That makes extended grazing a practice worth