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Effects of Feeding Broiler Litter-Based Diets on Live Animal Performance and Economics with Cull Beef Cows1
The Professional Animal Scientist 22 (2006):334–340
Effects of Feeding Broiler LitterBased Diets on Live Animal Performance and Economics 1 with Cull Beef Cows S. M. DeROUEN,*2 PAS, and D. H. FOSTER† *Hill Farm Research Station, Louisiana State University Agricultural Center, Homer 71040, and †Louisiana Department of Agriculture and Forestry, Baton Rouge 70821
Abstract The objectives of this study were to evaluate the potential of feeding and marketing of cull beef cows over a 3-yr period. From 65 to 81 thin cows were purchased in October (over a 2- to 3-wk period) each year from an auction barn. Cows were allocated by BW, body condition score, and breed type to 4 treatments (TRT) with 2 replicates per TRT. The TRT were 1) 80% composted broiler litter (BL) and 20% corn (C), 2) 80% BL and 20% soybean hulls (S), 3) 70% BL and 30% C, and 4) 70% BL and 30% S. The BL diets and hay were provided ad libitum. Length of trials ranged from 99 to 113 d, beginning in mid- or late-November and ending in early- or mid-March. Cows removed from each trial due to mortality or morbidity ranged from 9.6 to 16.0%. There were no differences (P = 0.16) among TRT for BL diet or hay DMI. Diet costs varied (P < 0.005) with BL diets including C having greater (P < 0.05) costs than BL diets
1
Approved for publication by the Director of Louisiana Agricultural Experiment Station as manuscript No. 05-54-0725. 2 To whom correspondence should be addressed: [email protected]
with S. Average daily gain, body condition score gain, and final BW were not different (P > 0.13) among TRT. At the end of each trial, cows were sold individually at a local auction barn. Overall final sale price ($0.99/kg) was 25% greater than overall purchase price ($0.79/kg). Final sale price (P = 0.10) and income generated (P < 0.05) tended to be greater or were greater for TRT 1 and 4 than for TRT 2 and 3. In conclusion, health status of cull cows purchased from an auction barn and seasonality in market value are important factors to consider for feeding and marketing of cull beef cows. Key words: cull cows, economics, management, marketing
Introduction Sales of cull beef cows represent 15 to 30% of the gross revenue of cow-calf enterprises (Little et al., 2002). Marketing of cull cows is often overlooked even though a significant proportion of total income is generated from these animals. The cull cow market fluctuates within a year and generally follows a seasonal pattern. Little et al. (2002) indicated that seasonal price variance is the primary economic
factor affecting cull cow profitability. Value is also affected by cow grade, with increased body condition generally increasing price (Gadberry et al., 2002). Apple (1999) concluded that increasing condition of cull cows to a body condition score (BCS) of 6 (1 to 9 scale; Richards et al., 1986) optimized live animal value. There are several by-products available that may serve as an economical feedstuff for feeding thin, cull cows. Composted broiler litter (BL) is one such by-product that is readily available in the southeastern United States. Currently there is an interim rule that bans the use of poultry litter as a feed ingredient for ruminant animals. This study was conducted prior to this ruling, so feeding of BL to cattle is currently not recommended. However, information gained from this study will still be useful. An energy supplement is usually added to BL diets to provide the desired level of gain. Corn is most commonly used, but soybean hulls are another energy feed source that are usually less costly than corn. Cows are generally culled from breeding herds following periods of undernutrition. When realimented, they fre-
Management and Marketing of Cull Beef Cows
quently have greater than normal rates of BW gain, thus resulting in compensatory gains (Wright and Russell, 1984). Swingle et al. (1979), Matulis et al. (1987), Cranwell et al. (1996), Schnell et al. (1997), and Sawyer et al. (2004) reported on feeding of thin cull cows with relatively high-concentrate diets for short durations. Studies are limited that evaluated cull cows consuming by-product diets over longer feeding periods. Therefore, the objectives of this study were to evaluate live animal performance and determine the economic implications of feeding different BLbased diets to purchased cull beef cows.
Materials and Methods Animals and Adjustment Period. All methods, conditions, and management procedures employed in this study were in compliance with the guidelines established by Louisiana State University Institutional Animal Care and Use Committee (IACUC #AE 99-19). This study was conducted in 3 consecutive yr, with 3 separate trials. From 65 to 81 thin cows were purchased each October over a 2- to 3-wk period from area livestock auction barns and transported to the Louisiana State University AgCenter Hill Farm Research Station near Homer, Louisiana. In general, breed composition of the cows was British, British-Brahman, Continental, Continental-Brahman, and British-Continental-Brahman. Cows exhibiting evidence of dairy breeding or more than 50% Brahman inheritance were not purchased. Only cows that were classified as 10 yr old or younger were purchased. Cows were processed at time of arrival at the station. Cows were individually identified with an identification ear tag, and received a vaccine for respiratory complex pathogens, viral diarrhea, parainfluenza, and rhinotracheitis (Vira Shield, Grand Laboratories, Novartis Ani-
mal Vaccines, Inc., Larchwood, IA) and were dewormed (Ivomec Plus, Merial Ltd., Iselin, NJ). Also at the time of arrival, cows were administrated a low dosage of a broad-spectrum antibiotic treatment (Maxim200, Phoenix Scientific, Inc., St. Joseph, MO). After processing, cows were offered bermudagrass hay ad libitum, had free access to clean water and minerals, and were supplemented daily with 1.0 to 1.5 kg of an equal amount of ground corn (C) and soybean hulls (S) for 5 d. The S were fed in the loose form during the adjustment and trial periods throughout the study. Thereafter, cows were supplemented daily with 2.27 kg of 85% C and S (equal amounts of each) and 15% composted BL for 3 d. The proportion of BL was increased by 15% every third day until the mixture was 75% BL and 25% C and S. The mixture was offered ad libitum when it was 60% BL and 40% C and S on d 9. Hay was provided ad libitum during the entire adjustment period. During processing and the 2-wk adjustment period, cows were observed frequently for health status. Any cows that exhibited anorexia, dehydration, or depression were not considered for the study. Due to mortality or health problems observed at processing or during the adjustment period, 1 to 4 cows per trial were not put in the study. Once the trial was initiated, cows were observed frequently (at least daily) for sickness. Animals that exhibited any health problems were removed from the study. Broiler Litter Diet Treatments. Cows were allocated by BW, BCS, and breed type to eight 0.81-ha paddocks (dormant bermudagrass paddocks) with 2 replicates for each of 4 BL diet treatments (TRT). The TRT were: 80% BL and 20% C (80BL-20C); 80% BL and 20% S (80BL-20S); 70% BL and 30% C (70BL-30C); and 70% BL and 30% S (70BL-30S). The ingredient and nutrient composition of the 4BL
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diets as well as the nutrient composition of hay provided by TRT are presented in Table 1. In addition to the cows having access to the BL diets and hay, they were also provided clean water and minerals. Lengths of feeding trials were 113, 100, and 99 d for trials 1, 2, and 3, respectively, with initiation occurring in mid- or late-November and ending in early- or mid-March. The BL diets were mixed every 7 to 14 d and placed in weather-protected feeders. The BL diets were offered ad libitum to the cows throughout the duration of the trial. Bermudagrass hay was also provided ad libitum to the cows for the duration of the trial. An effort was made to ensure that the hay provided to cows in all 8 paddocks was of similar quality based on CP and energy compositions. Measurements. Cows were purchased over a 2- to 3-wk period in October of each year. Purchase price ($/kg) and purchase cost ($/ head) were recorded for each cow. Purchasing and processing charges for buyer fees, hauling, medicine, and feed and hay consumed during the adjustment period were tracked and assessed on a per-cow basis. The sum of these purchasing, processing, and adjustment period charges is the start-up cost ($/ head). At the initiation of the trial, BCS were assigned by a minimum of 2 individuals, and the mean of the scores were recorded for initial BCS. On the following day, the cows were weighed again and the mean was used for initial BW. The cows were stratified by initial BW, BCS, and breed type (5 classifications) and randomized into treatment-replicate groups. Diet consumption was tracked on a per paddock basis. Orts were weighed and recorded and subtracted from the paddock’s total BL diet delivery. Amount of hay delivered to each paddock was also recorded. Round hay bales were weighed and placed in a hay ring. Amount of hay wastage was fac-
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Table 1. Ingredient (% of DM) and nutrient composition of broiler litter-based diets and hay by treatment diet.a Item
80BL-20C
80BL-20S
70BL-30C
70BL-30S
79.9 19.9 — 0.2
79.9 — 19.9 0.2
69.9 29.9 — 0.2
69.9 — 29.9 0.2
Nutrient composition of broiler litter dietsc DM, % 85.5 CP, % of DM 23.4 ADF, % of DM 31.6 1.26 NEm, Mcal/kg DMd NEg, Mcal/kg DMd 0.69
86.1 22.8 36.6 1.11 0.55
86.0 22.5 32.6 1.38 0.80
85.9 22.0 39.2 1.16 0.59
Nutrient composition of hayc DM, % CP, % of DM ADF, % of DM NEm, Mcal/kg DMd NEg, Mcal/kg DMd
90.3 10.2 40.1 0.90 0.40
90.0 10.2 40.9 0.93 0.39
90.1 10.0 39.6 0.94 0.41
Ingredients Broiler litter, % Ground corn, % Soybean hulls, % Vitamins A, D, and E, %b
89.9 9.9 40.3 0.91 0.38
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Provided 4,410 IU vitamin A, 1,322 IU vitamin D, and 36 IU vitamin E per kilogram of diet. c Nutrient composition averaged over the 3 trials. d Values calculated based on tabular values (NRC, 1996).
tored as 25% of delivery amount. Hay costs were determined based on the amount delivered. Diet intake and diet cost data were recorded on a per-paddock basis. Diet intake was tracked for all paddocks and diet costs were based on ingredient costs and amount delivered to the paddocks. Actual feed (as is) costs were used to calculate diet costs. Costs ($/Mg) of BL were $14.33, $18.74, and $9.92 for trials 1, 2, and 3, respectively. Costs ($/Mg) of ground C were $158.77, $143.33, and $143.33 for trials 1, 2, and 3, respectively. Costs ($/Mg) of S were $126.79, $102.54, and $104.74 for trials 1, 2, and 3, respectively. Hay cost remained constant over the 3 trials and was $55.13/Mg. The cows were weighed and scored for body condition at 28-d intervals for trial 1 or near the mid-point (d 49) for trials 2 and 3.
At the end of each trial, cows were scored for body condition (by a minimum of 2 individuals) and weighed on 2 consecutive days; the mean was used for final BW. After the termination of the trial, cows were transported to a local livestock auction barn and sold individually. Final sale price, final net sale value, and income generated were determined. Final net sale value is the gross final sale value less auction barn sale commission and other auction barn deductions including hauling. Income generated is the final net sale value less startup and diet costs. Interest on purchase of cow or feed as well as labor costs were not included for estimating income. Statistical Analysis. All data were analyzed as a randomized block design with BL diet as the treatment effect and year or trial as the block effect. Year × treatment
interaction was also included in the model and preliminary analysis found this effect was not important (P > 0.12) for any of the response traits studied. Paddock was the experimental unit for all measurements; however, data are expressed on a per-animal basis. All data were analyzed using a generalized linear mixed model procedure (PROC MIXED) of SAS (v. 9.0; SAS Inst., Inc., Cary, NC). Paddock within treatment was designated as a random effect and served as the error term for determining treatment effects. Least squares means were computed. When a significant F-test was detected, treatment differences were determined using selected linear contrasts (ESTIMATE procedure of SAS). Cows that exhibited any health problems were removed from the study and were not included in the analysis.
Results and Discussion Feeding of Composted Broiler Litter to Cattle. On January 26, 2004, responding to the first bovine spongiform encephalopathy case in the U.S. that occurred in December 2003, the Food and Drug Administration announced an interim rule that included a ban on the use of poultry litter as a feed ingredient for ruminant animals. This study was conducted prior to this ruling, so any feeding of BL to cattle is presently not recommended. However, regardless of ingredients used, information ascertained from this study will be useful for consideration in managing and marketing of cull beef cows. Health Status of Cull Cows. Six to 12 cows per trial were removed from the study during the course of the adjustment and feeding trial periods due to death or health problems (Table 2). Six of the 14 cows that died were the result of respiratory infections. One cow died due to a uterine prolapse and 2 other cows died due to complications from a uterine infection. The
Management and Marketing of Cull Beef Cows
Table 2. Number and percent of cull cows removed from the study due to health problems by trial.a
Item Trial 1 Trial 2 Trial 3
Mortality
Morbidity
No.
%
No.
%
4 8 2
5.0 9.8 3.2
8 4 4
11.0 4.9 6.4
a
Includes 1 to 4 cows per trial that died or were morbid during the adjustment period.
remaining 5 cows died from unknown causes. Percent mortality of cows over the 3 trials ranged from 3.2 to 9.8%. Cows classified as chronically ill were removed from the study upon diagnosis. Besides poor performance being exhibited by these chronically ill cows, other symptoms were anorexia, dehydration, or depressive behavior. The distribution of death losses and morbidity were fairly evenly distributed across TRT. Percent of cows that died or were morbid across the trials ranged from 9.6 to 16.0%. Sawyer et al. (2004) reported overall mortality and removal rates due to health reasons of 1.7 and 6.9%, respectively, although cows used in their study were obtained from a cooperating ranch. Purchase and Start-up Costs. Observed means and ranges for purchase price, purchase cost, and start-up cost are presented in Table 3 by trial. Purchase prices and costs were similar in trials 1 and 3, whereas in trial 2, prices and costs were 11 to 13% greater. The initial value of the cow (purchase cost) is the greatest cost of a cull cow feeding enterprise (Sawyer et al., 2004). Buyer fees and costs for hauling and medicine that were included in the start-up costs tended to increase each year. These purchase and start-up costs more importantly provide the basis to determine
income generated at the end of the trial. Broiler Litter Diet Intake, Hay Intake, and Diet Costs. The DMI of the BL diets and hay offered ad libitum, and the diet costs associated with each TRT are presented in Table 4. The BL diets and hay DMI were not influenced (P = 0.16) by TRT. However, BL diet DMI were numerically greater and hay DMI were numerically less for cows fed BL with 30% C and 30% S compared with cows fed BL with 20% C and 20% S. This indicates that cows offered a greater proportion of C or S in their diets consumed more of the BL diets and less of the hay. The levels of DMI of the BL diets and hay were 1.97, 2.05, 2.22, and 2.12% of BW for 80BL-20C, 80BL-20S, 70BL-30C, and 70BL-30S, respectively. Intake levels were greater in short-duration studies that fed primarily concentrate diets (Swingle et al., 1979; Matulis et al., 1987; Brown and Johnson, 1991; Cranwell et al. 1996; Sawyer et al. 2004). Diet costs varied (P < 0.005) among BL diets (Table 4). Diet costs were $14.10 less (P < 0.01) for cows fed 80BL-20C than for cows fed 70BL-30C. Likewise, diet costs tended to be less (P < 0.10) for cows fed 80BL-20S than for cows fed 70BL-30S. These greater diet costs with 30% C and 30% S would be expected due to greater ingredient costs of C and S and numerically greater DMI of these diets. The greater C prices relative to S resulted in $5.97 less (P < 0.05) diet costs for cows fed BL diets with S than those fed BL diets with C. Sawyer et al. (2004) reported numerically greater diet costs for cull cows fed conservative (greater roughage level) feeding strategies compared with cows fed standard and aggressive feeding strategies. Live Animal Performance. Body weights, BCS, ADG, and BCS gains of cows by BL diet are summarized in Table 5. Weight gains did not differ (P = 0.13) among the BL
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diets. There tended to be an advantage of 0.067 kg in ADG (P < 0.07) for cows fed BL diets with C compared with cows fed BL diets with S. Furthermore, cows fed BL diets with 30% C and 30% S had numerically greater ADG than cows fed BL diets with 20% C and 20% S. Final BW did not differ (P = 0.25) among the BL diet, which ranged from 496 to 507 kg. Swingle et al. (1979) reported that feeding thin cull range cows with greater levels of concentrates resulted in significantly greater rates of gain. Sawyer et al. (2004) indicated no significant differences among conservative, standard, and aggressive feeding strategies with cull cows; however, the more energy dense diets (standard and aggressive) had numerically greater ADG. Body condition scores and BCS gains by BL diet are shown in Table 5. Initial BCS ranged from 4.04 to 4.10 by BL diet indicating that cows were quite thin at the start of the trial. The BCS gains did not differ (P = 0.27) among BL diets. As was observed for ADG differences, there was a tendency for cows fed BL diets with C having numerically greater (P < 0.09) BCS gains than cows fed BL diets with S. The overall final BCS mean was < 5.0, indicating that the optimal BCS of 6 for finishing cull cows (Apple, 1999) was not achieved in this study. In general, live animal performance of the cows fed these BLbased diets was less than expected based on the nutrient composition of the diets and level of diet intake (NRC, 1996). Based on NRC (1996) nutrient requirements, cows fed these BL diets would be expected to achieve approximately 0.68 kg ADG. One factor that may have contributed to less than expected live animal performance is the large variation observed in BW and BCS gains of these cows whose background was unknown prior to purchasing. The variation in performance of these cows may also be
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Table 3. Observed means and ranges for purchase price, purchase cost, and start-up cost of cull cows by trial. Purchase price, $/kg Item Trial 1 Trial 2 Trial 3
Purchase cost, $/head
Start-up cost, $/heada
Mean
Range
Mean
Range
Mean
Range
0.76 0.85 0.77
0.74–0.80 0.83–0.87 0.69–0.85
325 373 331
311–345 361–387 305–360
348 401 363
335–369 390–415 337–394
a
Costs are the sum of purchasing, buyer fees, hauling, medicine, feed, and hay delivered during processing and adjustment period.
partially explained by individual variation of diet intake; it was observed that some cows consumed very little if any amount of the BL diets. Even when removing cows from the study due to detectible health reasons, there were those cows that responded with minimal BW and BCS gains without exhibiting apparent health problems,
whereas some cows responded with exceptional BW gains and improved BCS, regardless of BL diet. Final Sale Price, Final Net Sale Value, and Income Generated. The final sale price and net sale value of cows sold at a local auction barn and income generated by BL diet are summarized in Table 6. Overall final sale price ($0.99/kg)
Table 4. Broiler litter diet and hay DMI and diet costs of cull cows by treatment. Itema 80BL-20C 80BL-20S 70BL-30C 70BL-30S SEc P-valued
Broiler litter diet DMI, kg/d 3.86 3.95 5.40 4.92 0.495 0.16
Hay DMI, kg/d
Diet cost, $/headb
5.58 5.82 5.31 5.25 0.175 0.16
55.34 53.38 69.45 59.48 2.338 0.005
Broiler litter diet treatment contrastse 20C vs 30C 20S vs. 30S C vs. S a
−1.54 ± 0.71 −0.97 ± 0.71 0.20 ± 0.50
0.27 ± 0.24 0.57 ± 0.24 −0.09 ± 0.17
−14.10 ± 3.31** −6.10 ± 3.31† 5.97 ± 2.34*
80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Broiler litter cost = $14.33/Mg; corn cost = $148.48/Mg; soybean hulls cost = $111.36/Mg; and hay = $55.13/Mg. c Two paddocks per treatment. d The probability value for the treatment effect. e 20C vs 30C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/2 minus (80BL-20S + 70BL30S)/2. **P < 0.01; *P < 0.05; †P < 0.10.
was 25% greater than overall purchase price ($0.79/kg) reflecting the seasonality of cull cow market prices (fall market value < spring market value). There was a tendency for final sale price to vary (P = 0.10) by TRT. Those cows fed 80BL-20C tended to receive greater (P < 0.10) prices than cows fed 70BL-30C. In addition, cows fed 70BL-30S tended to receive greater (P < 0.10) prices than cows fed 80BL-20S. There is no apparent explanation for these sale price differences by BL diet especially when considering that final BW and BCS of cows did not differ (Table 5). As with final sale price, the net sales of cows fed 80BL-20C and70BL-30S had numerically greater values than cows fed 80BL-20S and 70BL30C. Income generated differed (P < 0.01) by BL diet. Cows fed 80BL20C generated $28.79 more (P < 0.05) income than cows fed 70BL30C. In addition, cows fed 70BL30S generated $36.70 more (P < 0.01) income than cows fed 80BL20S. The principal factors resulting in greater income for 80BL-20C and 70BL-30S diets were greater final sale prices (P < 0.10) as well as less diet costs (P < 0.01) for 80BL20C treatment.
Implications Health status of cows when obtained from an auction barn with unknown background needs to be considered and closely monitored
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Management and Marketing of Cull Beef Cows
Table 5. Body weight and body condition score (BCS) of cull cows by broiler litter diet treatment. Itema
Initial BW, kg
80BL-20C 80BL-20S 70BL-30C 70BL-30S SEd P-valuee
459 459 458 459 1.63 0.88
ADG, kgb
Final BW, kg
0.406 0.351 0.475 0.397 0.0324 0.13
Initial BCSc
500 496 507 500 4.7 0.25
BCS gain
4.07 4.04 4.10 4.09 0.036 0.57
0.70 0.47 0.72 0.60 0.091 0.27
Final BCS 4.77 4.51 4.82 4.69 0.093 0.61
Broiler litter diet treatment contrastsf 20C vs. 30C 20S vs. 30S C vs. S
0.4 ± 2.3 −0.3 ± 2.3 −0.8 ± 1.6
−0.069 ± 0.046 −0.046 ± 0.046 0.067 ± 0.032
6.93 ± 6.61 −4.50 ± 6.61 5.89 ± 4.67
−0.03 ± 0.05 −0.05 ± 0.05 0.02 ± 0.04
−0.02 ± 0.13 −0.13 ± 0.13 0.18 ± 0.09
−0.05 ± 0.13 −0.18 ± 0.13 −0.19 ± 0.09
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b ADG for entire trial period; trial 1 = 113 d, trial 2 = 100 d, and trial 3 = 99 d. c One to nine scale; Richards et al. (1986). d Two paddocks per treatment. e The probability value for the treatment effect. f 20 C vs 30 C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/ 2 minus (80BL-20S + 70BL-30S)/2.
Table 6. Final sale price, final net sale value, and income generated from cull cows by broiler litter diet treatment. Itema 80BL-20C 80BL-20S 70BL-30C 70BL-30S SEd P-valuee
Final sale price, $/kg 1.02 0.96 0.97 1.02 0.016 0.10
Final net sale value, $/headb
Income, $/headc
464.16 435.97 442.95 464.82 8.834 0.15
36.16 2.33 7.37 39.03 7.143 0.01
Broiler litter diet treatment contrastsf 20C vs. 30C 20S vs. 30S C vs. S
0.04 ± 0.022† −0.04 ± 0.022† 0.01 ± 0.016
21.21 ± 12.49 −28.85 ± 12.49 3.16 ± 8.83
28.79 ± 10.11* −36.70 ± 10.11** 9.79 ± 7.14
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Final net sale value = gross auction barn sale value minus commission and other auction barn deductions. c Income = final net sale value minus start-up and diet costs. d Two paddocks per treatment. e The probability value for the treatment effect. f 20 C vs 30 C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/2 minus (80BL-20S + 70BL30S)/2. **P < 0.01; *P < 0.05; †P < 0.10.
if a feeding program with cull cows is conducted. Capitalizing on seasonal price fluctuations associated with the cull cow market should be considered. Cow-calf enterprises may consider delaying the marketing of cows if they are normally culled and sold in the fall after weaning, particularly if these cows are thin and exhibit no apparent health concerns. Employing a feeding regimen for thin cull cows over the fall and winter that is designed to increase BW and BCS to optimal levels for marketing could substantially increase the value of these cull animals.
Literature Cited Apple, J. K. 1999. Influence of body condition score on live and carcass value of cull beef cows. J. Anim. Sci. 77:2610. Brown, W.F., and D. D. Johnson. 1991. Effects of energy and protein supplementation of ammoniated tropical grass hay on the growth and carcass characteristics of cull cows. J. Anim. Sci. 69:348.
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Cranwell, C. D., J. A. Unruh, F. R. Brethour, and D. D. Simms. 1996. Influence of steroid implants and concentrate feeding on performance and carcass composition of cull beef cows. J. Anim. Sci. 74:1770. Gadberry, M. S., T. R. Troxel, D. Urell, J. Foley, R. Wiedower, S. Cline, and G. Ford. 2002. Factors affecting the market value of cows sold through Arkansas auction barns. Part 1: Management. J. Anim. Sci. 80(Suppl. 1):103. Little, R. D., A. R. Williams, R. C. Lacy, and C. S. Forrest. 2002. Cull cow management and its implications for cow-calf profitability. J. Range Manage. 55:112. Matulis, R. J., F. K. McKeith, D. B. Faulkner, L. L. Berger, and P. George. 1987. Growth
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and carcass characteristics of cull cows after different times-on-feed. J. Anim. Sci. 65:669. NRC. 1996. Nutrient Requirements of Beef Cattle. 7th ed. Natl. Acad. Press, Washington, D.C. Richards, M. W., J. C. Spitzer, and M. B. Warner. 1986. Effect of varying levels of postpartum nutrition and body condition at calving on subsequent reproductive performance in beef cattle. J. Anim. Sci. 62:300. Sawyer, J. E., C. P. Mathis, and B. Davis. 2004. Effects of feeding strategy and age on live animal performance, carcass characteristics, and economics of short-term feeding programs for culled beef cows. J. Anim. Sci. 82:3646.
Schnell, T. D., K. E. Belk, J. D. Tatum, R. K. Miller, and G. C. Smith. 1997. Performance, carcass, and palatability traits for cull cows fed higher-energy concentrate diets for 0, 14, 28, 42, or 56 days. J. Anim. Sci. 75:1195. Swingle, R. S., C. B. Roubicek, R. A. Wooten, J. A. Marchello, and F. D. Dryden. 1979. Realimentation of cull range cows. I. Effect of final body condition and dietary energy level on rate of efficiency and composition of gains. J. Anim. Sci. 48:913. Wright, V. A., and A. J. Russel. 1984. Partition of fat, body composition, and body condition score in mature cows. Anim. Prod. 38:338.
Effects of Feeding Broiler LitterBased Diets on Live Animal Performance and Economics 1 with Cull Beef Cows S. M. DeROUEN,*2 PAS, and D. H. FOSTER† *Hill Farm Research Station, Louisiana State University Agricultural Center, Homer 71040, and †Louisiana Department of Agriculture and Forestry, Baton Rouge 70821
Abstract The objectives of this study were to evaluate the potential of feeding and marketing of cull beef cows over a 3-yr period. From 65 to 81 thin cows were purchased in October (over a 2- to 3-wk period) each year from an auction barn. Cows were allocated by BW, body condition score, and breed type to 4 treatments (TRT) with 2 replicates per TRT. The TRT were 1) 80% composted broiler litter (BL) and 20% corn (C), 2) 80% BL and 20% soybean hulls (S), 3) 70% BL and 30% C, and 4) 70% BL and 30% S. The BL diets and hay were provided ad libitum. Length of trials ranged from 99 to 113 d, beginning in mid- or late-November and ending in early- or mid-March. Cows removed from each trial due to mortality or morbidity ranged from 9.6 to 16.0%. There were no differences (P = 0.16) among TRT for BL diet or hay DMI. Diet costs varied (P < 0.005) with BL diets including C having greater (P < 0.05) costs than BL diets
1
Approved for publication by the Director of Louisiana Agricultural Experiment Station as manuscript No. 05-54-0725. 2 To whom correspondence should be addressed: [email protected]
with S. Average daily gain, body condition score gain, and final BW were not different (P > 0.13) among TRT. At the end of each trial, cows were sold individually at a local auction barn. Overall final sale price ($0.99/kg) was 25% greater than overall purchase price ($0.79/kg). Final sale price (P = 0.10) and income generated (P < 0.05) tended to be greater or were greater for TRT 1 and 4 than for TRT 2 and 3. In conclusion, health status of cull cows purchased from an auction barn and seasonality in market value are important factors to consider for feeding and marketing of cull beef cows. Key words: cull cows, economics, management, marketing
Introduction Sales of cull beef cows represent 15 to 30% of the gross revenue of cow-calf enterprises (Little et al., 2002). Marketing of cull cows is often overlooked even though a significant proportion of total income is generated from these animals. The cull cow market fluctuates within a year and generally follows a seasonal pattern. Little et al. (2002) indicated that seasonal price variance is the primary economic
factor affecting cull cow profitability. Value is also affected by cow grade, with increased body condition generally increasing price (Gadberry et al., 2002). Apple (1999) concluded that increasing condition of cull cows to a body condition score (BCS) of 6 (1 to 9 scale; Richards et al., 1986) optimized live animal value. There are several by-products available that may serve as an economical feedstuff for feeding thin, cull cows. Composted broiler litter (BL) is one such by-product that is readily available in the southeastern United States. Currently there is an interim rule that bans the use of poultry litter as a feed ingredient for ruminant animals. This study was conducted prior to this ruling, so feeding of BL to cattle is currently not recommended. However, information gained from this study will still be useful. An energy supplement is usually added to BL diets to provide the desired level of gain. Corn is most commonly used, but soybean hulls are another energy feed source that are usually less costly than corn. Cows are generally culled from breeding herds following periods of undernutrition. When realimented, they fre-
Management and Marketing of Cull Beef Cows
quently have greater than normal rates of BW gain, thus resulting in compensatory gains (Wright and Russell, 1984). Swingle et al. (1979), Matulis et al. (1987), Cranwell et al. (1996), Schnell et al. (1997), and Sawyer et al. (2004) reported on feeding of thin cull cows with relatively high-concentrate diets for short durations. Studies are limited that evaluated cull cows consuming by-product diets over longer feeding periods. Therefore, the objectives of this study were to evaluate live animal performance and determine the economic implications of feeding different BLbased diets to purchased cull beef cows.
Materials and Methods Animals and Adjustment Period. All methods, conditions, and management procedures employed in this study were in compliance with the guidelines established by Louisiana State University Institutional Animal Care and Use Committee (IACUC #AE 99-19). This study was conducted in 3 consecutive yr, with 3 separate trials. From 65 to 81 thin cows were purchased each October over a 2- to 3-wk period from area livestock auction barns and transported to the Louisiana State University AgCenter Hill Farm Research Station near Homer, Louisiana. In general, breed composition of the cows was British, British-Brahman, Continental, Continental-Brahman, and British-Continental-Brahman. Cows exhibiting evidence of dairy breeding or more than 50% Brahman inheritance were not purchased. Only cows that were classified as 10 yr old or younger were purchased. Cows were processed at time of arrival at the station. Cows were individually identified with an identification ear tag, and received a vaccine for respiratory complex pathogens, viral diarrhea, parainfluenza, and rhinotracheitis (Vira Shield, Grand Laboratories, Novartis Ani-
mal Vaccines, Inc., Larchwood, IA) and were dewormed (Ivomec Plus, Merial Ltd., Iselin, NJ). Also at the time of arrival, cows were administrated a low dosage of a broad-spectrum antibiotic treatment (Maxim200, Phoenix Scientific, Inc., St. Joseph, MO). After processing, cows were offered bermudagrass hay ad libitum, had free access to clean water and minerals, and were supplemented daily with 1.0 to 1.5 kg of an equal amount of ground corn (C) and soybean hulls (S) for 5 d. The S were fed in the loose form during the adjustment and trial periods throughout the study. Thereafter, cows were supplemented daily with 2.27 kg of 85% C and S (equal amounts of each) and 15% composted BL for 3 d. The proportion of BL was increased by 15% every third day until the mixture was 75% BL and 25% C and S. The mixture was offered ad libitum when it was 60% BL and 40% C and S on d 9. Hay was provided ad libitum during the entire adjustment period. During processing and the 2-wk adjustment period, cows were observed frequently for health status. Any cows that exhibited anorexia, dehydration, or depression were not considered for the study. Due to mortality or health problems observed at processing or during the adjustment period, 1 to 4 cows per trial were not put in the study. Once the trial was initiated, cows were observed frequently (at least daily) for sickness. Animals that exhibited any health problems were removed from the study. Broiler Litter Diet Treatments. Cows were allocated by BW, BCS, and breed type to eight 0.81-ha paddocks (dormant bermudagrass paddocks) with 2 replicates for each of 4 BL diet treatments (TRT). The TRT were: 80% BL and 20% C (80BL-20C); 80% BL and 20% S (80BL-20S); 70% BL and 30% C (70BL-30C); and 70% BL and 30% S (70BL-30S). The ingredient and nutrient composition of the 4BL
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diets as well as the nutrient composition of hay provided by TRT are presented in Table 1. In addition to the cows having access to the BL diets and hay, they were also provided clean water and minerals. Lengths of feeding trials were 113, 100, and 99 d for trials 1, 2, and 3, respectively, with initiation occurring in mid- or late-November and ending in early- or mid-March. The BL diets were mixed every 7 to 14 d and placed in weather-protected feeders. The BL diets were offered ad libitum to the cows throughout the duration of the trial. Bermudagrass hay was also provided ad libitum to the cows for the duration of the trial. An effort was made to ensure that the hay provided to cows in all 8 paddocks was of similar quality based on CP and energy compositions. Measurements. Cows were purchased over a 2- to 3-wk period in October of each year. Purchase price ($/kg) and purchase cost ($/ head) were recorded for each cow. Purchasing and processing charges for buyer fees, hauling, medicine, and feed and hay consumed during the adjustment period were tracked and assessed on a per-cow basis. The sum of these purchasing, processing, and adjustment period charges is the start-up cost ($/ head). At the initiation of the trial, BCS were assigned by a minimum of 2 individuals, and the mean of the scores were recorded for initial BCS. On the following day, the cows were weighed again and the mean was used for initial BW. The cows were stratified by initial BW, BCS, and breed type (5 classifications) and randomized into treatment-replicate groups. Diet consumption was tracked on a per paddock basis. Orts were weighed and recorded and subtracted from the paddock’s total BL diet delivery. Amount of hay delivered to each paddock was also recorded. Round hay bales were weighed and placed in a hay ring. Amount of hay wastage was fac-
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Table 1. Ingredient (% of DM) and nutrient composition of broiler litter-based diets and hay by treatment diet.a Item
80BL-20C
80BL-20S
70BL-30C
70BL-30S
79.9 19.9 — 0.2
79.9 — 19.9 0.2
69.9 29.9 — 0.2
69.9 — 29.9 0.2
Nutrient composition of broiler litter dietsc DM, % 85.5 CP, % of DM 23.4 ADF, % of DM 31.6 1.26 NEm, Mcal/kg DMd NEg, Mcal/kg DMd 0.69
86.1 22.8 36.6 1.11 0.55
86.0 22.5 32.6 1.38 0.80
85.9 22.0 39.2 1.16 0.59
Nutrient composition of hayc DM, % CP, % of DM ADF, % of DM NEm, Mcal/kg DMd NEg, Mcal/kg DMd
90.3 10.2 40.1 0.90 0.40
90.0 10.2 40.9 0.93 0.39
90.1 10.0 39.6 0.94 0.41
Ingredients Broiler litter, % Ground corn, % Soybean hulls, % Vitamins A, D, and E, %b
89.9 9.9 40.3 0.91 0.38
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Provided 4,410 IU vitamin A, 1,322 IU vitamin D, and 36 IU vitamin E per kilogram of diet. c Nutrient composition averaged over the 3 trials. d Values calculated based on tabular values (NRC, 1996).
tored as 25% of delivery amount. Hay costs were determined based on the amount delivered. Diet intake and diet cost data were recorded on a per-paddock basis. Diet intake was tracked for all paddocks and diet costs were based on ingredient costs and amount delivered to the paddocks. Actual feed (as is) costs were used to calculate diet costs. Costs ($/Mg) of BL were $14.33, $18.74, and $9.92 for trials 1, 2, and 3, respectively. Costs ($/Mg) of ground C were $158.77, $143.33, and $143.33 for trials 1, 2, and 3, respectively. Costs ($/Mg) of S were $126.79, $102.54, and $104.74 for trials 1, 2, and 3, respectively. Hay cost remained constant over the 3 trials and was $55.13/Mg. The cows were weighed and scored for body condition at 28-d intervals for trial 1 or near the mid-point (d 49) for trials 2 and 3.
At the end of each trial, cows were scored for body condition (by a minimum of 2 individuals) and weighed on 2 consecutive days; the mean was used for final BW. After the termination of the trial, cows were transported to a local livestock auction barn and sold individually. Final sale price, final net sale value, and income generated were determined. Final net sale value is the gross final sale value less auction barn sale commission and other auction barn deductions including hauling. Income generated is the final net sale value less startup and diet costs. Interest on purchase of cow or feed as well as labor costs were not included for estimating income. Statistical Analysis. All data were analyzed as a randomized block design with BL diet as the treatment effect and year or trial as the block effect. Year × treatment
interaction was also included in the model and preliminary analysis found this effect was not important (P > 0.12) for any of the response traits studied. Paddock was the experimental unit for all measurements; however, data are expressed on a per-animal basis. All data were analyzed using a generalized linear mixed model procedure (PROC MIXED) of SAS (v. 9.0; SAS Inst., Inc., Cary, NC). Paddock within treatment was designated as a random effect and served as the error term for determining treatment effects. Least squares means were computed. When a significant F-test was detected, treatment differences were determined using selected linear contrasts (ESTIMATE procedure of SAS). Cows that exhibited any health problems were removed from the study and were not included in the analysis.
Results and Discussion Feeding of Composted Broiler Litter to Cattle. On January 26, 2004, responding to the first bovine spongiform encephalopathy case in the U.S. that occurred in December 2003, the Food and Drug Administration announced an interim rule that included a ban on the use of poultry litter as a feed ingredient for ruminant animals. This study was conducted prior to this ruling, so any feeding of BL to cattle is presently not recommended. However, regardless of ingredients used, information ascertained from this study will be useful for consideration in managing and marketing of cull beef cows. Health Status of Cull Cows. Six to 12 cows per trial were removed from the study during the course of the adjustment and feeding trial periods due to death or health problems (Table 2). Six of the 14 cows that died were the result of respiratory infections. One cow died due to a uterine prolapse and 2 other cows died due to complications from a uterine infection. The
Management and Marketing of Cull Beef Cows
Table 2. Number and percent of cull cows removed from the study due to health problems by trial.a
Item Trial 1 Trial 2 Trial 3
Mortality
Morbidity
No.
%
No.
%
4 8 2
5.0 9.8 3.2
8 4 4
11.0 4.9 6.4
a
Includes 1 to 4 cows per trial that died or were morbid during the adjustment period.
remaining 5 cows died from unknown causes. Percent mortality of cows over the 3 trials ranged from 3.2 to 9.8%. Cows classified as chronically ill were removed from the study upon diagnosis. Besides poor performance being exhibited by these chronically ill cows, other symptoms were anorexia, dehydration, or depressive behavior. The distribution of death losses and morbidity were fairly evenly distributed across TRT. Percent of cows that died or were morbid across the trials ranged from 9.6 to 16.0%. Sawyer et al. (2004) reported overall mortality and removal rates due to health reasons of 1.7 and 6.9%, respectively, although cows used in their study were obtained from a cooperating ranch. Purchase and Start-up Costs. Observed means and ranges for purchase price, purchase cost, and start-up cost are presented in Table 3 by trial. Purchase prices and costs were similar in trials 1 and 3, whereas in trial 2, prices and costs were 11 to 13% greater. The initial value of the cow (purchase cost) is the greatest cost of a cull cow feeding enterprise (Sawyer et al., 2004). Buyer fees and costs for hauling and medicine that were included in the start-up costs tended to increase each year. These purchase and start-up costs more importantly provide the basis to determine
income generated at the end of the trial. Broiler Litter Diet Intake, Hay Intake, and Diet Costs. The DMI of the BL diets and hay offered ad libitum, and the diet costs associated with each TRT are presented in Table 4. The BL diets and hay DMI were not influenced (P = 0.16) by TRT. However, BL diet DMI were numerically greater and hay DMI were numerically less for cows fed BL with 30% C and 30% S compared with cows fed BL with 20% C and 20% S. This indicates that cows offered a greater proportion of C or S in their diets consumed more of the BL diets and less of the hay. The levels of DMI of the BL diets and hay were 1.97, 2.05, 2.22, and 2.12% of BW for 80BL-20C, 80BL-20S, 70BL-30C, and 70BL-30S, respectively. Intake levels were greater in short-duration studies that fed primarily concentrate diets (Swingle et al., 1979; Matulis et al., 1987; Brown and Johnson, 1991; Cranwell et al. 1996; Sawyer et al. 2004). Diet costs varied (P < 0.005) among BL diets (Table 4). Diet costs were $14.10 less (P < 0.01) for cows fed 80BL-20C than for cows fed 70BL-30C. Likewise, diet costs tended to be less (P < 0.10) for cows fed 80BL-20S than for cows fed 70BL-30S. These greater diet costs with 30% C and 30% S would be expected due to greater ingredient costs of C and S and numerically greater DMI of these diets. The greater C prices relative to S resulted in $5.97 less (P < 0.05) diet costs for cows fed BL diets with S than those fed BL diets with C. Sawyer et al. (2004) reported numerically greater diet costs for cull cows fed conservative (greater roughage level) feeding strategies compared with cows fed standard and aggressive feeding strategies. Live Animal Performance. Body weights, BCS, ADG, and BCS gains of cows by BL diet are summarized in Table 5. Weight gains did not differ (P = 0.13) among the BL
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diets. There tended to be an advantage of 0.067 kg in ADG (P < 0.07) for cows fed BL diets with C compared with cows fed BL diets with S. Furthermore, cows fed BL diets with 30% C and 30% S had numerically greater ADG than cows fed BL diets with 20% C and 20% S. Final BW did not differ (P = 0.25) among the BL diet, which ranged from 496 to 507 kg. Swingle et al. (1979) reported that feeding thin cull range cows with greater levels of concentrates resulted in significantly greater rates of gain. Sawyer et al. (2004) indicated no significant differences among conservative, standard, and aggressive feeding strategies with cull cows; however, the more energy dense diets (standard and aggressive) had numerically greater ADG. Body condition scores and BCS gains by BL diet are shown in Table 5. Initial BCS ranged from 4.04 to 4.10 by BL diet indicating that cows were quite thin at the start of the trial. The BCS gains did not differ (P = 0.27) among BL diets. As was observed for ADG differences, there was a tendency for cows fed BL diets with C having numerically greater (P < 0.09) BCS gains than cows fed BL diets with S. The overall final BCS mean was < 5.0, indicating that the optimal BCS of 6 for finishing cull cows (Apple, 1999) was not achieved in this study. In general, live animal performance of the cows fed these BLbased diets was less than expected based on the nutrient composition of the diets and level of diet intake (NRC, 1996). Based on NRC (1996) nutrient requirements, cows fed these BL diets would be expected to achieve approximately 0.68 kg ADG. One factor that may have contributed to less than expected live animal performance is the large variation observed in BW and BCS gains of these cows whose background was unknown prior to purchasing. The variation in performance of these cows may also be
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Table 3. Observed means and ranges for purchase price, purchase cost, and start-up cost of cull cows by trial. Purchase price, $/kg Item Trial 1 Trial 2 Trial 3
Purchase cost, $/head
Start-up cost, $/heada
Mean
Range
Mean
Range
Mean
Range
0.76 0.85 0.77
0.74–0.80 0.83–0.87 0.69–0.85
325 373 331
311–345 361–387 305–360
348 401 363
335–369 390–415 337–394
a
Costs are the sum of purchasing, buyer fees, hauling, medicine, feed, and hay delivered during processing and adjustment period.
partially explained by individual variation of diet intake; it was observed that some cows consumed very little if any amount of the BL diets. Even when removing cows from the study due to detectible health reasons, there were those cows that responded with minimal BW and BCS gains without exhibiting apparent health problems,
whereas some cows responded with exceptional BW gains and improved BCS, regardless of BL diet. Final Sale Price, Final Net Sale Value, and Income Generated. The final sale price and net sale value of cows sold at a local auction barn and income generated by BL diet are summarized in Table 6. Overall final sale price ($0.99/kg)
Table 4. Broiler litter diet and hay DMI and diet costs of cull cows by treatment. Itema 80BL-20C 80BL-20S 70BL-30C 70BL-30S SEc P-valued
Broiler litter diet DMI, kg/d 3.86 3.95 5.40 4.92 0.495 0.16
Hay DMI, kg/d
Diet cost, $/headb
5.58 5.82 5.31 5.25 0.175 0.16
55.34 53.38 69.45 59.48 2.338 0.005
Broiler litter diet treatment contrastse 20C vs 30C 20S vs. 30S C vs. S a
−1.54 ± 0.71 −0.97 ± 0.71 0.20 ± 0.50
0.27 ± 0.24 0.57 ± 0.24 −0.09 ± 0.17
−14.10 ± 3.31** −6.10 ± 3.31† 5.97 ± 2.34*
80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Broiler litter cost = $14.33/Mg; corn cost = $148.48/Mg; soybean hulls cost = $111.36/Mg; and hay = $55.13/Mg. c Two paddocks per treatment. d The probability value for the treatment effect. e 20C vs 30C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/2 minus (80BL-20S + 70BL30S)/2. **P < 0.01; *P < 0.05; †P < 0.10.
was 25% greater than overall purchase price ($0.79/kg) reflecting the seasonality of cull cow market prices (fall market value < spring market value). There was a tendency for final sale price to vary (P = 0.10) by TRT. Those cows fed 80BL-20C tended to receive greater (P < 0.10) prices than cows fed 70BL-30C. In addition, cows fed 70BL-30S tended to receive greater (P < 0.10) prices than cows fed 80BL-20S. There is no apparent explanation for these sale price differences by BL diet especially when considering that final BW and BCS of cows did not differ (Table 5). As with final sale price, the net sales of cows fed 80BL-20C and70BL-30S had numerically greater values than cows fed 80BL-20S and 70BL30C. Income generated differed (P < 0.01) by BL diet. Cows fed 80BL20C generated $28.79 more (P < 0.05) income than cows fed 70BL30C. In addition, cows fed 70BL30S generated $36.70 more (P < 0.01) income than cows fed 80BL20S. The principal factors resulting in greater income for 80BL-20C and 70BL-30S diets were greater final sale prices (P < 0.10) as well as less diet costs (P < 0.01) for 80BL20C treatment.
Implications Health status of cows when obtained from an auction barn with unknown background needs to be considered and closely monitored
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Management and Marketing of Cull Beef Cows
Table 5. Body weight and body condition score (BCS) of cull cows by broiler litter diet treatment. Itema
Initial BW, kg
80BL-20C 80BL-20S 70BL-30C 70BL-30S SEd P-valuee
459 459 458 459 1.63 0.88
ADG, kgb
Final BW, kg
0.406 0.351 0.475 0.397 0.0324 0.13
Initial BCSc
500 496 507 500 4.7 0.25
BCS gain
4.07 4.04 4.10 4.09 0.036 0.57
0.70 0.47 0.72 0.60 0.091 0.27
Final BCS 4.77 4.51 4.82 4.69 0.093 0.61
Broiler litter diet treatment contrastsf 20C vs. 30C 20S vs. 30S C vs. S
0.4 ± 2.3 −0.3 ± 2.3 −0.8 ± 1.6
−0.069 ± 0.046 −0.046 ± 0.046 0.067 ± 0.032
6.93 ± 6.61 −4.50 ± 6.61 5.89 ± 4.67
−0.03 ± 0.05 −0.05 ± 0.05 0.02 ± 0.04
−0.02 ± 0.13 −0.13 ± 0.13 0.18 ± 0.09
−0.05 ± 0.13 −0.18 ± 0.13 −0.19 ± 0.09
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b ADG for entire trial period; trial 1 = 113 d, trial 2 = 100 d, and trial 3 = 99 d. c One to nine scale; Richards et al. (1986). d Two paddocks per treatment. e The probability value for the treatment effect. f 20 C vs 30 C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/ 2 minus (80BL-20S + 70BL-30S)/2.
Table 6. Final sale price, final net sale value, and income generated from cull cows by broiler litter diet treatment. Itema 80BL-20C 80BL-20S 70BL-30C 70BL-30S SEd P-valuee
Final sale price, $/kg 1.02 0.96 0.97 1.02 0.016 0.10
Final net sale value, $/headb
Income, $/headc
464.16 435.97 442.95 464.82 8.834 0.15
36.16 2.33 7.37 39.03 7.143 0.01
Broiler litter diet treatment contrastsf 20C vs. 30C 20S vs. 30S C vs. S
0.04 ± 0.022† −0.04 ± 0.022† 0.01 ± 0.016
21.21 ± 12.49 −28.85 ± 12.49 3.16 ± 8.83
28.79 ± 10.11* −36.70 ± 10.11** 9.79 ± 7.14
a 80 BL-20C = 80% broiler litter + 20% corn; 80BL-20S = 80% broiler litter + 20% soybean hulls; 70 BL-30C = 70% broiler litter + 30% corn; 70 BL-30S = 70% broiler litter + 30% soybean hulls. b Final net sale value = gross auction barn sale value minus commission and other auction barn deductions. c Income = final net sale value minus start-up and diet costs. d Two paddocks per treatment. e The probability value for the treatment effect. f 20 C vs 30 C = 80 BL-20C minus 70BL-30C; 20S vs 30S = 80BL-20S minus 70BL-30S; and C vs S = (80BL-20C + 70BL-30C)/2 minus (80BL-20S + 70BL30S)/2. **P < 0.01; *P < 0.05; †P < 0.10.
if a feeding program with cull cows is conducted. Capitalizing on seasonal price fluctuations associated with the cull cow market should be considered. Cow-calf enterprises may consider delaying the marketing of cows if they are normally culled and sold in the fall after weaning, particularly if these cows are thin and exhibit no apparent health concerns. Employing a feeding regimen for thin cull cows over the fall and winter that is designed to increase BW and BCS to optimal levels for marketing could substantially increase the value of these cull animals.
Literature Cited Apple, J. K. 1999. Influence of body condition score on live and carcass value of cull beef cows. J. Anim. Sci. 77:2610. Brown, W.F., and D. D. Johnson. 1991. Effects of energy and protein supplementation of ammoniated tropical grass hay on the growth and carcass characteristics of cull cows. J. Anim. Sci. 69:348.
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Cranwell, C. D., J. A. Unruh, F. R. Brethour, and D. D. Simms. 1996. Influence of steroid implants and concentrate feeding on performance and carcass composition of cull beef cows. J. Anim. Sci. 74:1770. Gadberry, M. S., T. R. Troxel, D. Urell, J. Foley, R. Wiedower, S. Cline, and G. Ford. 2002. Factors affecting the market value of cows sold through Arkansas auction barns. Part 1: Management. J. Anim. Sci. 80(Suppl. 1):103. Little, R. D., A. R. Williams, R. C. Lacy, and C. S. Forrest. 2002. Cull cow management and its implications for cow-calf profitability. J. Range Manage. 55:112. Matulis, R. J., F. K. McKeith, D. B. Faulkner, L. L. Berger, and P. George. 1987. Growth
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and carcass characteristics of cull cows after different times-on-feed. J. Anim. Sci. 65:669. NRC. 1996. Nutrient Requirements of Beef Cattle. 7th ed. Natl. Acad. Press, Washington, D.C. Richards, M. W., J. C. Spitzer, and M. B. Warner. 1986. Effect of varying levels of postpartum nutrition and body condition at calving on subsequent reproductive performance in beef cattle. J. Anim. Sci. 62:300. Sawyer, J. E., C. P. Mathis, and B. Davis. 2004. Effects of feeding strategy and age on live animal performance, carcass characteristics, and economics of short-term feeding programs for culled beef cows. J. Anim. Sci. 82:3646.
Schnell, T. D., K. E. Belk, J. D. Tatum, R. K. Miller, and G. C. Smith. 1997. Performance, carcass, and palatability traits for cull cows fed higher-energy concentrate diets for 0, 14, 28, 42, or 56 days. J. Anim. Sci. 75:1195. Swingle, R. S., C. B. Roubicek, R. A. Wooten, J. A. Marchello, and F. D. Dryden. 1979. Realimentation of cull range cows. I. Effect of final body condition and dietary energy level on rate of efficiency and composition of gains. J. Anim. Sci. 48:913. Wright, V. A., and A. J. Russel. 1984. Partition of fat, body composition, and body condition score in mature cows. Anim. Prod. 38:338.