|
Darrell Rankins, Jr., Jerry Van Dyke, Eddy Peacock, and Brian Gamble
Replacement
beef heifers and stocker steers are often fed diets containing broiler
litter. The diet usually consists of equal quantities of litter and
an energy source, such as corn or hominy feed. In a previous Highlights
report (Spring 1996), the importance of feeding hay with this mixture
was reported. However, many questions have been raised regarding the
quantity and quality of the fiber source that should be offered in addition
to the litter-grain mix.
Two studies were conducted to provide answers to these questions. Study
1 was conducted at the Sand Mountain Substation in Crossville. Forty-eight
Angus x Charolais steers (average weight of 440 pounds) were placed
in pens with four steers per pen. Steers were then fed one of four diets
over a 112-day period. The diets were as follows: (1) 50% broiler litter
and 50% cracked corn, (2) diet 1 plus daily hay at three pounds per
steer, (3) diet 1 plus hay fed on Mondays and Thursdays to equal the
amount fed in diet 2, and (4) diet 1 plus free-choice hay. The hay was
primarily orchard-grass (80%) and some endophyte-free tall fescue (20%)
and would be classified as high-quality hay (12% crude protein and 55%
neutral detergent fiber). The broiler litter had been deepstacked and
covered prior to feeding. In addition, all diets contained Bovatec™,
which is a feed additive used to enhance feed efficiency and, in this
case, was used as a bloat preventative.
Study 2 was conducted at the Wiregrass Substation in Headland Fifty
predominantly Brangus steers (average weight 597 pounds) were placed
in pens with five steers per pen and fed for 112 days. The diets were
as follows: (1) 50% broiler litter and 50% cracked corn; (2) diet 1
plus daily hay at 3.2 pounds per steer; (3) 45% broiler litter, 45%
cracked corn and 10% peanut hulls; (4) diet 1 plus free-choice hay;
and (5) diet 1 plus free-choice peanut hulls. The hay was primarily
bermudagrass and would be classified as medium- to high-quality (12%
crude protein and 60% neutral detergent fiber). The peanut hulls would
be classified as a low-quality fiber source. As in study 1, the litter
was deep-stacked and covered and all diets contained Bovatec.
In study 1, the fastest and most efficient gains were observed in
the cattle being fed hay on a daily basis or free-choice (Table 1).
The slowest gains were observed for the cattle receiving no hay. In
general, the increased weight gains were a result of increased intake,
presumably stimulated by the additional fiber. If one simply considers
feed costs, the most cost effective gains were produced using the hay
on a free-choice basis. The most expensive gains were those using no
hay or feeding the hay twice weekly. The following prices were used
to calculate these figures: corn, $110 per ton; broiler litter, $20
per ton; hay, $60 per ton; and Bovatec, $5 per pound.

In study 2, the best daily gains were by the steers supplemented with
hay; however, the most economical gains were by the steers fed free-choice
peanut hulls (Table 2). The same prices were used to calculate cost
of gain as were used in the first study. In addition, peanut hulls were
free. If the peanut hulls were to be purchased, the price that could
be paid based on these data (i.e., comparing free-choice hay to free-choice
hulls) is $27.23 per ton and be equivalent to the hay results at $60/ton.
A point to note in each of these studies is that the daily gains were
quite good. Most producers should expect daily gains of about 2 to 2.25
pounds per day. The reason for these differences is that, after cattle
are received, they are held for about three weeks prior to beginning
the study so they have time to adapt before initial weight. If daily
gains were calculated as pay-weight to pay-weight, they would be about
2 to 2.25 pounds per day.
Average daily gains were similar for both studies; however, the lighter
weight cattle used in the Sand Mountain study were more efficient than
the heavier cattle used for the Wiregrass study. This would be true for
most situations involving 150-pound weight differences. When using a high-quality
hay, gains were increased by 0.2 to 0.3 pounds per day when the hay was
offered free-choice versus a limit feeding. It is important to note that
in these studies the free-choice hay was fed as square bales in a concrete
feed bunk.
As this information is applied to a field situation, one would assume
that most hay would be offered free-choice in the form of a round bale,
which would result in a considerable amount of the hay being wasted and
would therefore increase the cost of this strategy. When comparing the
high-quality roughage (hay) to the low-quality roughage (peanut hulls),
daily gains were lower when the hulls were used, but as mentioned previously,
the peanut hulls would be worth $27 per ton if hay is worth $60 per ton.
As the price of hay increases, the value of the peanut hulls would also
increase.
Based on these results, the most economical gains will be produced by
offering the roughage in a free-choice manner. A low-quality source of
fiber may be used if the cost of that fiber source is low enough. Low-quality,
in this case, refers to the amount of digestible nutrients in the fiber
source. If the roughage is moldy or unpalatable, this would not necessarily
be true.
Rankins and Van Dyke are Associate Professors
of Animal and Dairy Sciences; Peacock is Herd Supervisor at the Sand
Mountain Substation; and Gamble is Associate Superintendent at the
Wiregrass Substation.
|