Performance of beef calves provided molasses-based creep supplements

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Performance of beef calves provided molasses-based creep supplements
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Arthington, John
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Performance of Beef Calves Provided Molasses-Based Creep Supplements


John ArthingtonI


Molasses-based liquid creep supplements have the advantage of self-limiting intake in suckling beef
calves. Performance and economic responses are highly variable among years.


Summary
These results support the earlier findings by Dr.
Bill Kunkle and his research involving limit-
creep supplements based on cottonseed meal
and salt mixtures. Calf performance responses,
as measured by the added gain realized by creep
supplementation, are highly variable and cannot
always be described by amounts of creep feed
consumed. This variability has large and direct
impacts on the cost effectiveness of the
management system. In our studies, using liquid
molasses-based creep supplements, we realized
a 4-year average cost of gain of $0.53 / lb of
added gain not including the costs associated
with feeding equipment and labor. A 1hh1 iugh this
value may appear cost-effective, in 2 of the 4
study years, the cost of added gain exceeded the
per lb value of the calves we sold. These studies
evaluated an array of molasses-based
supplement formulas including those with urea,
urea & Alimett, and cottonseed meal. We did
not evaluate sugarcane molasses (blackstrap)
alone, which may be a consideration within
future study designs. Further, it is important to
note that pasture forage conditions likely have a
significant impact on the effectiveness of limit-
fed creep supplements, particularly when these
supplements are offered to older calves in the
last months prior to weaning. In our
experiments, we realized significant variation in
the crude protein content of the bahiagrass
pastures between experiments. In Experiment 2,
pasture crude protein concentrations were
greater and calf response to creep
supplementation was poorer than in Experiment
1. There is a likely potential that these two


factors are related and may influence the results
achieved. Our future studies will attempt to
incorporate different pasture forage types (i.e.
limpograss vs. bahiagrass) and nutritional
quality among our treatment factors. Efforts to
better understand the variability in calf
responses to limit-creep supplements will assist
producers in making decisions on when the
management system may add value to their beef
production enterprise.

Introduction
Creep feeding is a management tool used to
provide supplemental nutrients to pre-weaned
calves. The word "creep" refers to the process
by which the calf is allowed to creep into (or
access) a space that is designed to exclude the
cow. There are multiple designs of systems that
will achieve this goal ranging from complex to
very simple. In general, fencing structures or
electrified wire that is positioned 36 to 42 inches
above the ground are adequate to allow calf
access but exclude cow access. The rationale
for creep feeding is centered on the concept that
the cow's milk will only provide about half of
the nutrition required by a 4 month-old calf.
Without supplemental feed, the calf must obtain
the remainder of its nutrition from forage. Often
the forage base may be of limited quality for the
calf to fulfill this deficit. This is further
complicated by an inability to consume large
amounts of forage due to an underdeveloped
rumen. If milk and forage together cannot
supply the calf with adequate nutrition, then sub-
optimal body weight gain can be expected.


'Range Cattle Research and Education Center, University of Florida, Ona, FL.










There are three types or categories of creep
feeding. Two types involve the provision of
feed or feed byproducts, within a cow-exclusion
area, that are offered either 1) free-choice
(unlimited creep), or 2) limited (limited-intake
creep). The third type involves the management
of a high-quality pasture forage that is only
allowed to be grazed by pre-weaned calves (i.e.
creep grazing).

Decisions regarding creep feeding beef calves
must weigh the cost of implementing this
management tool against the value of unrealized
body weight due to inadequate nutrition. Most
studies involving unlimited creep feeding have
found that the value of this "added" gain, due to
creep feeding, is poorly efficient, meaning that
the pounds of creep feed needed to produce 1 lb
of added gain is typically more costly than the
value of that added gain. During the early
weeks of creep feeding it is not uncommon for
this ratio to be as great at 12 to 15:1. As days of
creep feeding advance, this conversion ratio
typically improves, thus producers can realize
the greatest economic benefits of creep feeding
when the management system can be applied to
the herd for over 90 d. Despite the number of
days creep feeding is offered, the economics of
the practice continue to be debatable. Calves
will experience some level of daily gain, even if
creep feed is not provided, so it is important that
beef producers understand the calculation used
to estimate "added" gain. Added gain is the
difference between the daily gain of calves
consuming creep feed compared to those not
consuming creep feed. This added gain is
attributed to the creep feed consumed and is
often of less value than the cost of feed required
to produce it. In general, unlimited creep
feeding becomes more economical as feed prices
decrease and calf prices increase.

The economic considerations described above
occur when unlimited creep feed is provided.
Another option for consideration is limited creep
feeding, which is designed to provide a small
amount of supplemental nutrition targeted to fill
gaps in protein and/or energy deficiency and
compliment the value of the milk and forage
consumed by the calf. In Florida, Dr. Bill


Kunkle previously investigated the effects of
providing cottonseed meal to pre-weaned calves.
Intake was limited by the inclusion of salt,
which was gradually increased in the formula
(up to 8%) to limit intake to approximately 0.50
to 0.75 lb/d. A summary of 6 experiments
revealed that calves experienced 0.30 lb/d of
added gain while consuming an average of 0.65
lb of cottonseed meal daily. Each pound of
added gain required 2.2 lb of cottonseed meal.
Although these experiments revealed significant
variation among studies, they collectively
suggest that pre-weaned beef calves can
experience efficient, cost-effective added gains
when provided limit-fed creep supplements.

In Florida, as well as much of the Gulf coast
region, the use of molasses-based liquid feeds
for the supplementation of beef cows is
common. These supplements can be fortified to
increase the protein, energy, and/or vitamin and
mineral profile of the product. Some of
ingredients commonly added to molasses
supplements include urea, vegetable meals (i.e.
cottonseed meal), byproducts (dried distillers
grains), fats and oil, and minerals and vitamins.
Molasses-based supplements are also readily
consumed by pre-weaned calves and have an
added benefit of self-limiting intake.

The objective of these studies was to examine
the influence of free-choice, molasses-based
creep supplements on the efficiency and cost-
effectiveness of added gain in pre-weaned beef
calves.

Materials and Methods
Two experiments were conducted at the Range
Cattle Research and Education Center in Ona.
Each experiment was repeated in consecutive
years resulting in 4 years of data. The
experiments were conducted using fall-calving
(October December) beef herds and were
initiated in April of each year and concluded at
weaning (122, 117, 104, and 102 d,
respectively). Liquid creep supplements were
based on a sugarcane molasses carrier with
ingredients added as described below.
Supplements were offered to calves in cow-
exclusion areas within open 90-gallon tubs.










Experiment 1
The first experiment used Braford cow/calf pairs
grazing established summer bahiagrass pastures
(20 ac each). Cow/calf pairs were initially
stratified by cow age and randomly assigned to
pastures (approximately 17 cow/calf pairs per
pasture). Treatments consisted of 1) no creep, 2)
molasses + urea creep, and 3) molasses + urea +
Alimet creep. Alimet (Novus International,
St. Louis, MO), a commercial source of rumen
bypass sulfur-containing amino acids (TSAA),
was blended into the molasses + urea
formulation (0.63% as-fed basis) and provided
0.22% TSAA. The rationale for including
Alimet was to investigate the potential
influence of supplemental TSAA on pre-weaned
calf growth. The nutrient profile of the
supplements and bahiagrass pasture are shown
in Table 1.

Experiment 2
The second experiment used Brangus-crossbred
cow/calf pairs grazing established bahiagrass
pastures. Treatments were applied to 12
pastures (5 ac) containing 4 and 3 cow/calf pairs
in yr 1 and 2, respectively. Treatments consisted
of 1) no creep, 2) molasses + urea creep, and 3)
molasses + cottonseed meal creep. The nutrient
profile of the supplements and bahiagrass
pasture are shown in Table 1.

Data Collection
In each of the 4 study years, calf body weight,
cow body condition, and cow body weight
(following 12-h feed withdrawal) was recorded
at the start and end of the creep supplementation
period. Calf body weight was adjusted for sex
of calf. Creep intake was determined by
weighing each tub in 14-d intervals and
disappearance calculated. Pasture forage quality
was assessed by hand-plucked samples collected
in June of each year.

Statistical Analyses
All responses were analyzed by fitting mixed
models using the PROC MIXED procedure of
SAS (SAS Institute Inc., 1996). The model
statement included the treatment and time (when
appropriate). Data were analyzed using pasture
(treatment*year) as the random variable.
Pasture was the experimental unit. Means were


considered different when F test P values were <
0.10.

Results
Supplement Intake
There was annual variation in the consumption
of liquid creep supplement in Experiment 1 with
almost twice as much supplement consumed in
Year 2 vs. Year 1 (Table 2). Further, in Year 2,
calves provided creep supplements with
Alimet consumed almost 1/3 less supplement
than calves provided supplements without
Alimet. This difference is likely due to an
offensive odor, which is characteristic of this
ingredient. There was no treatment or treatment
x year interactions for supplement intake in
Experiment 2, with calves consuming an average
of 1.03 lb of supplement daily (Table 2).

Calf Performance
In Experiment 1, creep supplementation resulted
in 0.14 lb/d of added gain compared to calves
receiving no creep supplement. The average
daily gain (ADG) of calves consuming
supplements containing Alimet was 5.1% less
than calves consuming supplements without
Alimet (Table 3). This response is likely the
result of reduced supplement intake rather than a
direct adverse effect on calf growth. Although
supplement intake was greater in Experiment 1
than in Experiment 2, there was no effect of
treatment on calf ADG in Experiment 2 (Table
4). Overall, calf ADG was less in both years of
Experiment 2 compared to those in Experiment
1 (Figure 1).

The cost of the base molasses + urea supplement
was $137/ton (delivered, Ona, FL). Calculated
cost of gain was highly variable ($0.10 to $4.45 /
lb of added gain) and due primarily to annual
differences in added gain among creep-fed
calves. An overall assessment of added gain and
creep intake revealed a 4-yr average cost of gain
of $0.57/lb of added gain (Table 5).

Cow Performance
There was no impact of creep supplement on
change in cow body weight or body condition
score (Tables 6 and 7); however, cows in










Experiment 2 had less body weight and body
condition at both the start and end of the
supplementation period compared to cows in the
first experiment.

















Table 1. Nutrient profile of molasses supplements and pastures from Exp.
Item Exp. 1 Exp. 2 Exp. 2
Molasses Molasses + Molasses +
+ Urea 1 Urea Cottonseed
meal 2


Crude protein


21.0


19.0


16.4


1 and 2.
Exp. 1
Pasture


Exp. 2
Pasture (Yr.


Exp. 2
Pasture (Yr.


% (DM basis) ---------------------------------------
8.6 11.8 19.3


Acid detergent fiber -- -- 4.6 40.7 -- 34.0
Neutral detergent fiber -- -- 5.7 69.5 -- 64.0
Total digestible nutrients 75.0 72.0 71.1 56.3 -- 61.0
Ca 0.95 0.85 0.75 0.30 -- 0.30
P 0.06 0.07 0.29 0.19 -- 0.39
Mg 0.42 0.39 0.45 0.24 -- 0.22
K 5.20 4.90 4.19 1.02 -- 2.12
Na 0.122 0.078 0.185 0.010 ----- 0.021
1A third treatment in Exp. 1, was created by blending Alimet (Novus International, St. Louis, MO) into the molasses +
urea formulation (0.63% as-fed basis) to provide 0.22% TSAA.
2Blackstrap molasses + cottonseed meal blend (80:20; as-fed basis).


Table 2. Voluntary intake of creep feed over 100 days prior to weaning (lb/d) 1


Item Molasses + Molasses + Pooled
Urea Urea + Alimet SEM P value
Exp. 1 (Yr. 1) 0.19 0.19 0.023 1.00
Exp. 1 (Yr. 2) 0.59 0.41 0.023 0.004

Molasses + Molasses + Pooled
Urea Cottonseed Meal SEM P value
Exp. 2 (Yr. 1 & 2) 0.91 1.14 0.18 0.39


' Creep intake was determined by weighing individual 90-gallon tubs on 14-day intervals and disappearance calculated


---------------------------------------









Table 3. Effects of creep-feed formulations containing molasses and urea
performance of beef calves over 100 days prior to weaning (Exp. 1).


with or without Alimet on


Treatment Contrasts
Item No Creep Molasses + Molasses + SEM Alimet vs. Creep vs.
Urea Urea + Alimet No Alimet No Creep
April body 358 364 363 5.9 0.84 0.40
weight, lb
Weaning body 575 602 589 6.9 0.10 0.01
weight, lb
ADG, lb/d 1.95 2.14 2.03 0.034 0.03 0.007
1Pooled results of a total of 265 calves (2 years; 8 pastures/year; n = 3 pastures each for creep supplements
and 2 pastures for no creep control.




Table 4. Effects of creep-feed formulations containing molasses and urea or cottonseed meal on
performance of beef calves over 100 days prior to weaning (Exp. 2).1
Treatment Contrasts
Item No Creep Molasses + Molasses + SEM Urea vs. Creep vs.
Urea Cottonseed meal Cottonseed No Creep
meal
April body 302 287 287 7.4 0.99 0.15


weight, lb
Weaning body 468 453 461 9.8 0.58
weight, lb
ADG, lb/d 1.37 1.35 1.46 0.053 0.15
1Pooled results of a total of 84 calves (2 years; 12 pastures/year; n = 4 pastures/treatment.


0.39

0.55


= No Creep


Year 1 Year 2 Year 3 Year4 Overall


Figure 1. Effect of liquid, molasses-based creep (treatments pooled within year) over 4 years.
Experiment 1 = Years 1 and 2 and Experiment 2 = Years 3 and 4.















Table 5. Cost of added gain for creep-fed calves
Item Added Gain, lb/d Creep Intake, lb/d Cost of Gain, $
Exp. 1; Year 1 0.13 0.19 0.10
Exp. 1; Year 2 0.12 0.50 0.29
Exp. 2; Year 1 0.01 0.65 4.45
Exp. 2; Year 2 0.07 1.42 1.39
Overall Total 2 38 294 0.53
'Cost of gain based on $137/ton sugarcane molasses delivered (Ona, FL) without consideration to costs
of feeding equipment or labor.
2Overall total cost of gain calculated from the total gain and creep intake within the individual creep
feeding periods of each study year (122, 117, 104, and 102 days, respectively).


Table 6. Effects of calf creep-feed formulations containing molasses and urea with or without Alimet on
body weight (BW) and body condition score (BCS) of beef cows over 100 days prior to weaning (Exp. 1).
Treatment Contrasts
Item No Creep Molasses + Molasses + SEM Alimet vs. Creep vs.
Urea Urea + Alimet No Alimet No Creep
----------------- b ------------------
April BW' 1072 1070 1081 14.4 0.56 0.83
Weaning BW 1139 1166 1169 14.4 0.88 0.19
BW Change 71 90 93 10.7 0.75 0.17
--------------------1 to 5 scale -----------
April BCS 5.2 5.0 4.9 0.16 0.57 0.23
Weaning BCS 5.9 5.9 5.8 0.19 0.55 0.94
BCS Change 0.7 1.0 0.9 0.07 0.58 0.05
'Shrunk BW following a 12-hour feed withdrawal.













Table 7. Effects of calf creep-feed formulations containing molasses and urea or cottonseed meal on body
weight (BW) and body condition score (BCS) of beef cows over 100 days prior to weaning (Exp. 2).
Treatment Contrasts
Item No Creep Molasses + Molasses + SEM Urea vs. Creep vs.
Urea Cottonseed Cottonseed No Creep
Meal Meal
----------- b --------b -------------
April BW' 961 919 928 20.1 0.75 0.16
Weaning BW 1025 981 982 19.2 0.98 0.11
BW Change 66 59 50 10.7 0.53 0.32
-------------------1 to 9 scale -----------
April BCS 4.3 4.0 4.1 0.18 0.74 0.36
Weaning BCS 4.7 4.3 4.6 0.16 0.18 0.25
BCS Change 0.46 0.22 0.50 0.157 0.18 0.53
'Shrunk BW following a 12-hour feed withdrawal.




Full Text

PAGE 1

Summary These results support the earlier findings by Dr. Bill Kunkle and his research involving limit creep supplements based on cottonseed meal and salt mixtures. Calf performance responses, as measured by the added gain realized by creep supplementation, are highly variable and cannot always be described by amounts of c reep feed consumed. This variability has large and direct impacts on the cost effectiveness of the management system. In our studies, using liquid molasses based creep supplements, we realized a 4 year average cost of gain of $0.53 / lb of added gain n ot including the costs associated with feeding equipment and labor. Although this value may appear cost effective, in 2 of the 4 study years, the cost of added gain exceeded the per l b value of the calves we sold. These studies evaluated an array of mola sses based supplement formulas including those with urea, urea & Alimet, and cottonseed meal. We did not evaluate sugarcane molasses (blackstrap) alone, which may be a consideration within future study designs. Further, it is important to note that past ure forage conditions likely have a significant impact on the effectiveness of limit fed creep supplements, particularly when these supplements are offered to older calves in the last months prior to weaning. In our experiments, we realized significant va riation in the crude protein content of the bahiagrass pastures between experiments. In Experiment 2, pasture crude protein concentrations were greater and calf response to creep supplementation was poorer than in Experiment 1. There is a likely potential that these two factors are relate d and may influence the results achieved. Our future studies will attempt to incorporate different pasture forage types (i.e. limpograss vs. bahiagrass) and nutritional quality among our treatment factors. Efforts to better understand the variability in calf responses to limit creep supplements will assist producers in making decisions on when the management system may add value to their beef production enterprise. Introduction Creep feeding is a management tool used to provide supplemental nutrients to pre weaned by which the calf is allowed to creep into (or access) a space that is designed to exclude the cow. There are multiple designs of systems that will achieve thi s goal ranging from complex to very simple. In general, fencing structures or electrified wire that is positioned 36 to 42 inches above the ground are adequate to allow calf access but exclude cow access. The rationale for creep feeding is centered on t he concept that the nutrition required by a 4 month old calf. Without supplemental feed, the calf must obtain the remainder of its nutrition from forage. Often the forage base may be of limited quality for t he calf to fulfill this deficit. This is further complicated by an inability to consume large amounts of forage due to an underdeveloped rumen. If milk and forage together cannot supply the calf with adequate nutrition, then sub optimal bod y weight gain can be expected. Performance of Beef Calves Provided Molasses Based Creep Supplements John Arthington 1 Molasses based liquid creep supplements have the advantage of self limiting intake in suckling beef calves. Performance and economic responses are highly variable among years. 1 R ange Cattle Research and Education Center, University of Florida, Ona, FL.

PAGE 2

There are three types or categories of creep feeding. Two types involve the provision of feed or feed byproducts, within a cow exclusion area, that are offered either 1) free choice (unlimited creep), or 2) limited (limite d intake creep). The third type involves the management of a high quality pasture forage that is only allowed to be grazed by pre weaned calves (i.e. creep grazing). Decisions regarding creep feeding beef calves must weigh the cost of implementing this management tool against the value of unrealized body weight due to inadequate nutrition. Most studies involving unlimited creep feeding have creep feeding, is poorly efficient, meaning that the pounds of c reep feed needed to produce 1 lb of added gain is typically more costly than the value of that added gain. During the early weeks of creep feeding it is not uncommon for this ratio to be as great at 12 to 15:1. As days of creep feeding advance, this conv ersion ratio typically improves, thus producers can realize the greatest economic benefits of creep feeding when the management system can be applied to the herd for over 90 d Despite the number of days creep feeding is offered, the economics of the p ractice continue to be debatable. Calves will experience some level of daily gain, even if creep feed is not provided, so it is important that beef producers understand the calculation used difference between t he daily gain of calves consuming creep feed compared to those not consuming creep feed. This added gain is attributed to the creep feed consumed and is often of less value than the cost of feed required to produce it. In general, unlimited creep feeding becomes more economical as feed prices decrease and calf prices increase. The economic considerations described above occur when unlimited creep feed is provided. Another option for consideration is limited creep feeding, which is designed to provide a s mall amount of supplemental nutrition targeted to fill gaps in protein and/or energy deficiency and compliment the value of the milk and forage consumed by the calf. In Florida, Dr. Bill Kunkle previously investigated the effects of providing cottonseed meal to pre weaned calves. Intake was limited by the inclusion of salt, which was gradually increased in the formula (up to 8%) to limit intake to approximately 0.50 to 0.75 lb/d. A summary of 6 experiments revealed that calves experienced 0.30 lb/d of a dded gain while consuming an average of 0.65 lb of cottonseed meal daily. Each pound of added gain required 2.2 lb of cottonseed meal. Although these experiments revealed significant variation among studies, they collectively suggest that pre weaned beef calves can experience efficient, cost effective added gains when provided limit fed creep supplements. In Florida, as well as much of the Gulf coast region, the use of molasses based liquid feeds for the supplementation of beef cows is common. These supp lements can be fortified to increase the protein, energy, and/or vitamin and mineral profile of the product. Some of ingredients commonly added to molasses supplements include urea, vegetable meals (i.e. cottonseed meal), byproducts (dried distillers grai ns), fats and oil, and minerals and vitamins. Molasses based supplements are also readily consumed by pre weaned calves and have an added benefit of self limiting intake. The objective of these studies was to examine the influence of free choice, molass es based creep supplements on the efficiency and cost effectiveness of added gain in pre weaned beef calves. Materials and Methods Two experiments were conducted at the Range Cattle Research and Education Center in Ona. Each experiment was repeated in c onsecutive years resulting in 4 years of data. The experiments were conducted using fall calving (October December) beef herds and were initiated in April of each year and concluded at weaning (122, 117, 104, and 102 d respectively). Liquid creep s upplements were based on a sugarcane molasses carrier with ingredients added as described below. Supplements were offered to calves in cow exclusion areas within open 90 gallon tubs.

PAGE 3

Experiment 1 The first experiment used Braford cow/calf pairs grazing e stablished summer bahiagrass pastures (20 ac each). Cow/calf pairs were initially stratified by cow age and randomly assigned to pastures (approximately 17 cow/calf pairs per pasture). Treatments consisted of 1) no creep, 2) molasses + urea creep, and 3) molasses + urea + Alimet creep. Alimet (Novus International, St. Louis, MO), a commercial source of rumen bypass sulfur containing amino acids (TSAA), was blended into the molasses + urea formulation (0.63% as fed basis) and provided 0.22% TSAA. The r ationale for including Alimet was to investigate the potential influence of supplemental TSAA on pre weaned calf growth. The nutrient profile of the supplements and bahiagrass pasture are shown in Table 1. Experiment 2 The second experiment used Brangus crossbred cow/calf pairs grazing established bahiagrass pastures. Treatments were applied to 12 pastures (5 ac) containing 4 and 3 cow/calf pairs in y r 1 and 2, respectively. Treatments consisted of 1) no creep, 2) molasses + urea creep, and 3) molasse s + cottonseed meal creep. The nutrient profile of the supplements and bahiagrass pasture are shown in Table 1. Data Collection In each of the 4 study years, calf body weight, cow body condition, and cow body weight (following 12 h feed withdrawal) was recorded at the start and end of the creep supplementation period. Calf body weight was adjusted for sex of calf. Creep intake wa s determined by weighing each tub in 14 d intervals and disappearance calculated. Pasture forage quality was assessed by hand plucked samples collected in June of each year. Statistical Analyses All responses were analyzed by fitting mixed models using the PROC MIXED procedure of SAS (SAS Institute Inc., 1996). The model statement included the treatment and time (when appropriate). Data were analyzed using pa s ture ( treatment*year) as the random variable. Pasture was the experimental unit. Means were considered different when F test P values were < 0.10. Results Supplement Intake There was annual variation in the consumption of liquid creep supplement in Experiment 1 with almost twice as much supplement consumed in Year 2 vs. Year 1 (Table 2). Furt her, in Year 2, calves provided creep supplements with Alimet consumed almost 1/3 less supplement than calves provided supplements without Alimet. This difference is likely due to an offensive odor, which is characteristic of this ingredient. There was no treatment or treatment x year interactions for supplement intake in Experiment 2, with calves consuming an average of 1.03 lb of supplement daily (Table 2). Calf Performance In Experiment 1, creep supplementation resulted in 0.14 lb/d of added gain co mpared to calves receiving no creep supplement. The average daily gain ( ADG ) of calves consuming supplements containing Alimet was 5.1% less than calves consuming supplements without Alimet (Table 3). This response is likely the result of reduced suppl ement intake rather than a direct adverse effect on calf growth. Although supplement intake was greater in Experiment 1 than in Experiment 2, there was no effect of treatment on calf ADG in Experiment 2 (Table 4). Overall, calf ADG was less in both years of Experiment 2 compared to those in Experiment 1 (Figure 1). The cost of the base molasses + urea supplement was $137/ton (delivered, Ona, FL). Calculated cost of gain was highly variable ($0.10 to $4.45 / lb of added gain) and due primarily to annual differences in added gain among creep fed calves. An overall assessment of added gain and creep intake revealed a 4 y r average cost of gain of $0.57/lb of added gain (Table 5). Cow Performance There was no impact of creep supplement on change in cow body weight or body condition score (Tables 6 and 7); however, cows in

PAGE 4

Experiment 2 had less body weight and body condition at both the start and end of the supplementation period compared to cows in the first experiment.

PAGE 5

Table 1 Nutrient profile of molasses supplements and pastures from Exp. 1 and 2. Item Exp. 1 Molasses + Urea 1 Exp. 2 Molasses + Urea Exp. 2 Molasses + Cottonseed meal 2 Exp. 1 Pasture Exp. 2 Pasture (Yr. 1) Exp. 2 Pasture (Yr. 2) --------------------------------------% (DM basis) --------------------------------------C rude protein 21.0 19.0 16.4 8.6 11.8 19.3 Acid detergent fiber --------4.6 40.7 ----34.0 Neutral detergent fiber --------5.7 69.5 ----64.0 Total digestible nutrients 75.0 72.0 71.1 56.3 ----61.0 Ca 0.95 0.85 0.75 0.30 ----0.30 P 0.06 0.07 0.29 0.19 ----0.39 Mg 0.42 0.39 0.45 0.24 ----0.22 K 5.20 4.90 4.19 1.02 ----2.12 Na 0.122 0.078 0.185 0.010 ----0.021 1 A third treatment in Exp. 1, was created by blending Alimet (Novus International, St. Louis, MO) into the molasses + urea formulation (0.63% as fed basis) to provide 0.22% TSAA. 2 Blackstrap molasses + cottonseed meal blend (80:20; as fed basis). Table 2. Voluntary intake of creep feed over 100 days prior to weaning (lb/d) 1 Item Molasses + Urea Molasses + Urea + Alimet Pooled SEM P value Exp. 1 (Yr. 1) 0.19 0.19 0.023 1.00 Exp. 1 (Yr. 2) 0.59 0.41 0.023 0.004 Molasses + Urea Molasses + Cottonseed Meal Pooled SEM P value Exp. 2 (Yr. 1 & 2) 0.91 1.14 0.18 0.39 1 Creep intake was determined by weighing individual 90 gallon tubs on 14 day intervals and disappearance calculated

PAGE 6

Table 3. Effects of creep feed formulations containing molasses and urea with or without Alimet on performance of beef calves over 100 days prior to weaning (Exp. 1). Treatment Contrasts Item No Creep Molasses + Urea Molasses + Urea + Alimet SEM Alimet vs. No Alimet Creep vs. No Creep April body weight lb 358 364 363 5.9 0.84 0.40 Weaning body weight lb 575 602 589 6.9 0.10 0.01 ADG lb/d 1.95 2.14 2.03 0.034 0.03 0.007 1 Pooled results of a total of 265 calves (2 years; 8 pastures/year; n = 3 pastures each for creep supplements and 2 pastures for no creep control. Table 4. Effects of creep feed formulations containing molasses and urea or cottonseed meal on performance of beef calves over 100 days prior to weaning (Exp. 2). 1 Treatment Contrasts Item No Creep Molasses + Urea Molasses + Cottonseed meal SEM Urea vs. Cottonseed meal Creep vs. No Creep April body weight lb 302 287 287 7.4 0.99 0.15 Weaning body weight lb 468 453 461 9.8 0.58 0.39 ADG lb/d 1.37 1.35 1.46 0.053 0.15 0.55 1 Pooled results of a total of 84 calves (2 years; 12 pastures/year; n = 4 pastures/treatment. Figure 1. Effect of liquid, molasses based creep (treatments pooled within year) over 4 years. Experiment 1 = Years 1 and 2 and Experiment 2 = Years 3 and 4.

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Table 5. Cost of added gain for creep fed calves Item Added Gain, lb/d Creep Intake, lb/d Cost of Gain, $ 1 Exp. 1; Year 1 0.13 0.19 0.10 Exp. 1; Year 2 0.12 0.50 0.29 Exp. 2; Year 1 0.01 0.65 4.45 Exp. 2; Year 2 0.07 1.42 1.39 Overall Total 2 38 294 0.53 1 Cost of gain based on $137/ton sugarcane molasses delivered (Ona, FL) without consideration to costs of feeding equipment or labor. 2 Overall total cost of gain calculated from the total gain and creep intake within the individual creep feeding periods of each study year (122, 117, 104, and 102 days, respectively). T able 6. Effects of calf creep feed formulations containing molasses and urea with or without Alimet on body weight (BW) and body condition score (BCS) of beef cows over 100 days prior to weaning (Exp. 1). Treatment Contrasts Item No Creep Molasses + Urea Molasses + Urea + Alimet SEM Alimet vs. No Alimet Creep vs. No Creep -------------------lb ---------------------April BW 1 1072 1070 1081 14.4 0.56 0.83 Weaning BW 1 1139 1166 1169 14.4 0.88 0.19 BW Change 71 90 93 10.7 0.75 0.17 -------------------1 to 5 scale -----------------April BCS 5.2 5.0 4.9 0.16 0.57 0.23 Weaning BCS 5.9 5.9 5.8 0.19 0.55 0.94 BCS Change 0.7 1.0 0.9 0.07 0.58 0.05 1 Shrunk BW following a 12 hour feed withdrawal.

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Table 7. Effects of calf creep feed formulations containing molasses and urea or cottonseed meal on body weight (BW) and body condition score (BCS) of beef cows over 100 days prior to weaning (Exp. 2). Treatment Contrasts Item No Creep Molasses + Urea Molasses + Cottonseed Meal SEM Urea vs. Cottonseed Meal Creep vs. No Creep -------------------lb ---------------------April BW 1 961 919 928 20.1 0.75 0.16 Weaning BW 1 1025 981 982 19.2 0.98 0.11 BW Change 66 59 50 10.7 0.53 0.32 ------------------1 to 9 scale -----------------April BCS 4.3 4.0 4.1 0.18 0.74 0.36 Weaning BCS 4.7 4.3 4.6 0.16 0.18 0.25 BCS Change 0.46 0.22 0.50 0.157 0.18 0.53 1 Shrunk BW following a 12 hour feed withdrawal.