Nonwithdrawal Molting Programs
K. W. Koelkebeck[1], C. M. Parsons, P. Biggs, and P. Utterback
Department of Animal Sciences, 1207 W. Gregory Dr., University of Illinois, Urbana, IL 61801
SUMMARY
In the commercial egg industry the management practice using feed withdrawal to induce a flock to molt has been under extreme scrutiny. This is because animal rights groups have voiced their concern about using this practice. Thus, about 5 yr ago, the United Egg Producers (UEP) commissioned five universities to conduct induced molting experiments in order to develop alternative molting programs which employed non-feed withdrawal to molt laying hens. The studies conducted to date used techniques ranging from feeding hens without added salt in the diet to using readily available, low cost feed ingredients to develop molt diets that are low in energy level and protein content. The results of these studies indicated that molting laying hens without feed withdrawal can be done successfully. Research at the University of Illinois found that feeding laying hens diets consisting of wheat middlings, soybean hulls, in combination with corn (low protein and low energy) were successful in providing for acceptable postmolt egg production performance and economical benefit compared to using a standard feed withdrawal method. Therefore, after five years of experimenting with non-feed withdrawal molting methods done in several university settings, the egg industry has successfully adopted these methods of molting laying hens. In addition, based on the finding of these experiments, the UEP has revised their recommended molting guidelines to state that only non-feed withdrawal molting methods will be permitted after January 1, 2006. Thus, these guidelines will apply to approximately 82% of the U.S. egg industry.
DESCRIPTON OF PROBLEM
There are several types of induced molting programs that are currently used in today’s commercial egg industry. These programs vary mainly in the length of feed withdrawal and the type of molt diet fed following the feed withdrawal period. All of these programs involve the use of feed withdrawal to produce a cessation of egg production. These programs recommend using feed withdrawal periods of varying lengths. In one study, the flock was deprived of feed until they reached a target body weight loss. The length of feed withdrawal in this program is usually at least 10 d and possibly longer [1]. Other molting programs that have involved the use of a short feed withdrawal period (4 to 5 d) have yielded good postmolt egg performance results, but long-term egg shell quality is often compromised [2].
In recent years, concern for the well-being of hens during an induced molt has been expressed by animal activists groups. Two such groups, United Poultry Concerns and the Association of Veterinarians for Animal Rights, have petitioned the USDA and FDA to eliminate induced molting of laying hens in the U.S. They contend that hens experience stress and “extreme cruelty” due to the removal of feed which is necessary to induce a molt. As a result of these concerns, industry organizations have called for research to be conducted in this area. The UEP has recommended that producers and university researchers work together to develop alternative molting techniques that do not involve the use of feed withdrawal to initiate a molt. Many food companies such as McDonalds, Burger King and Wendy’s International have told companies that supply them with eggs not to use feed withdrawal programs to initiate a molt. Currently, many legislators in Washington, DC are being pressured by animal rights groups to force the egg industry to disallow the practice of induced molting. Thus, the development of viable and economical methods of induced molting without feed withdrawal is very important.
Previous research which has been conducted on non-feed withdrawal laying hen molt programs have utilized various techniques to induce a molt. Among them has been the feeding of high levels of zinc and the use of alternative feed ingredients. In one study, laying hens were fed very high levels of zinc and found that egg production was slightly better and egg weights were heavier for hens induced to molt when fed 1% zinc acetate and 1% zinc propionate compared to a conventional feed withdrawal method [3]. In a study using cottonseed diets researchers found that feeding hens a diet containing 50% finely ground cottonseed produced voluntary feed intake reduction. This method was determined to be equivalent in effectiveness to one produced by a complete feed withdrawal program [4]. In another study, the feeding of a diet composed mostly of grape pomace containing 10 ppm thyroxine was effective in supporting similar postmolt performance as a conventional feed withdrawal method [5]. Thus, the above mentioned studies and many others have documented that laying hens can be molted by other means besides a conventional feed withdrawal.
Because of the previously mentioned pressures of animal rights groups on the egg industry to ban the practice of induced molting of hens by feed withdrawal, in 1999 the UEP commissioned five universities to conduct research in this area. The purpose of this was to have each university develop alternative molting programs which could be presented to the egg industry and easily adopted by the producers themselves. The five universities included, University of Nebraska, North Carolina State University, University of California, University of Arkansas, and the University of Illinois.
Research on alternative molting programs at the University of Nebraska revolved around the feeding of “nutrient balanced” diets (1250 MEn kcal/lb, 10 and 12.5% protein, 1.5% calcium, and .5% available phosphorus) with 0% added salt compared to a conventional feed withdrawal program [6]. Their program also called for increasing the photoperiod to 16 or 24 h of light for one wk prior to the initiation of the molt treatments. In their research, the level of sodium did not affect feed intake, however, cessation of lay and body weight loss was not as complete as those hens molted by an 8- to 10-d fasting method. In addition, they found that fasted birds had better egg shell quality in the postmolt production period. In the work conducted at North Carolina State University four molting techniques which consisted of a no molted group; a long fast (12 d followed by a full-fed diet, 16% protein, 2% calcium); a short fast (5 d followed by feeding a low protein/energy maintenance diet (10% protein, 1650 MEn kcal/kg) containing corn, soybean hulls, and wheat middlings to 28 d; and feeding the low protein/energy diet full-fed to 28 d were compared [7]. In this work, all hens (66 wk of age) were given 24 h of light one wk prior to the start, then placed on 9 h of total light per day until Day 28. The photoperiod was increased to 14 h on Day 28 and 16.5 h on Day 31 and the hens were fed a standard layer diet from Day 28 to the end at 107 wk of age. The results indicated that using a low protein/energy molt diet without fasting provided good postmolt results and is feasible for the industry to use. Furthermore, the non-fasting method resulted in comparable egg production, egg income, and feed costs compared to the fasting methods. In the research at the University of California, five field tests using paired houses on three California commercial egg farms were conducted [8]. Relative flock performance of flocks molted by traditional feed removal methods compared to using diets with low levels of sodium, calcium, and protein was evaluated. In general, egg production and body weight losses differed between the two molting methods during the first 4 wk of the test, but performance after that was similar. Mixed economic results were noted between the two methods used. In the work done at the University of Arkansas, the approach was to feed hens a molt diet containing supplemental iodinate thyroxine (T4) [9]. This work has shown promise and the authors have been granted a patent license agreement to continue doing the work.
Our approach at the University of Illinois has been to develop a non-feed withdrawal molting program which is easy for the industry to implement, uses feed ingredients that are inexpensive, and ones which are readily available. Our hypothesis has been that an acceptable non-feed withdrawal molting program could be implemented by feeding a molt diet that is low in energy and protein and one which is palatable to the birds. We have used non-feed withdrawal molting diets that have been composed of wheat middlings, soybean hulls, corn gluten meal, and other ingredients by themselves and in combination with corn. Thus, the following report is a summary of research that we have done. Funding for this research was provided by a number of sources [10].
MATERIALS AND METHODS
In the studies that we have conducted, DeKalb Whites and Hy-Line W-36 hens were used and housed in a commercial-type cage layer facility with 3 hens per cage (72 in.2 per hen). In all studies, the photoperiod was reduced from 17 to 10 h per d at the start of each study that began in the summer months and lasted for 44 wk (4 wk for the molt period and 40 wk for the postmolt lay period). After the molt period all hens were fed a layer diet (16% protein, 2,865 kcal/kg MEn) from Weeks 5 to 44, and the photoperiod was gradually increased back to 17 h following the molt period. Experimental set-up, data measurement and collection, and statistical analysis for all studies reported herein were previously described in our earlier work [11]. For all studies reported herein, all data were analyzed by ANOVA procedures appropriate for a one-way completely randomized design. The Fisher’s protected least significant difference test was used to determine significant differences among treatment means [12].
RESULTS AND DISCUSSION
Study 1. In the first study, DeKalb White strain hens at 60 wk of age were used [11]. They were either continually fed a corn diet, a wheat middlings diet, fasted for 4 d, then fed a corn diet, or fasted for 10 d, then fed a corn diet (Table 1). The results of this study showed that feeding a high wheat middlings diet produced a reduction in egg production by Day 8 and the hens stayed out of production until Day 15 (Figure 1). The return to egg production after the initiation of feeding the layer diet is summarized in Table 2. Postmolt egg production was generally higher for those hens fed the wheat middlings molt diet and 10-d feed removal treatments than for the corn and 4-d feed removal treatments. Hens fed the wheat middlings molt diet reached 50% egg production the soonest with peak egg production being 89.6% and 90.7% for the 10-d feed removal treatment. Postmolt hen-day egg production was significantly greater for hens deprived of feed for 10 d compared to those fed the corn molt diet and deprived of feed for 4 d during Weeks 5 to 44 (Table 2). In addition, egg production was not significantly different for hens fed the wheat middlings molt diet and those deprived of feed for 10 d. There were no differences in postmolt mortality between any of the treatments during Weeks 5 to 44 (data not shown). These results indicated that postmolt egg production of hens fed a high wheat middlings molt diet equaled that for hens that were deprived of feed for 10 d.
Finally, Table 3 depicts the effect of the molt treatments on postmolt egg income minus feed costs for Weeks 1 to 44. Egg income minus feed costs were compared using the total number of eggs produced and total feed (molt plus layer) consumed for all hens in each treatment. Egg income was based on a price of $.70 per dozen [13]. As noted in Table 3, the hens which were deprived of feed for 10 d had the highest egg income minus feed costs, with hens fed the wheat middlings molt diet producing the second highest profit. Thus, this study indicated that feeding a diet that was high in wheat middlings would induce hens to molt and postmolt performance was nearly equal to a program which utilized a conventional feed withdrawal molting technique.
Study 2. After discovering that a non-feed withdrawal molting program that used wheat middlings would work, we decided to use other feed ingredients and combinations. In this study, we tested the feeding of wheat middlings, corn, corn gluten feed, corn distillers grain, and combinations of wheat middlings and corn [14]. Again we fed hens the molt diets which were low in energy and the combinations of wheat middlings and corn was implemented to improve flowability in a commercial feeding system. The composition of the molt diet treatments used in this study is depicted in Table 4.
Table 5 shows the molt period and overall egg production from Weeks 5 to 44 following the molt period. The hens that were without feed for 10 d, then fed a 16% protein corn-soybean diet had the highest egg production from Weeks 5 to 44, while those fed the 71:23% wheat middlings/corn diet had slightly lower egg production. For hen-housed egg production, the hens that were subjected to feed withdrawal for 10 d, then fed a 16% protein diet produced the most eggs per hen housed (200), followed by those hens fed the 71:23% wheat middlings/corn diet (194) (data not shown).
Table 6 depicts the economic comparisons between treatments for egg income minus feed costs for Weeks 1 to 44 [15]. These results indicate that the most profitable molting program occurred for those hens that had feed withdrawn for 10 d, then fed the 16% corn-soybean meal molt diet. The next best profitable program was the one where hens were continuously fed the 71:23% wheat middlings:corn molt diet.
Study 3. After examining the results of the previous studies, we noticed that using a non-feed withdrawal molt diet program using wheat middlings, soybean hulls, and various combinations of the two with corn we could not induce the hens to go completely out of production. This would in turn affect production and egg shell quality late in the postmolt production period, although it was difficult to actually observe this in our previous work. Therefore, in an ongoing study, we are evaluating six treatments that include feeding wheat middlings and corn combinations, and soybean hulls and corn combinations compared to a conventional 10-day fasting treatment (10-d fast). In the six diet combinations we are feeding two of them full fed (C:WM and C:SH), two combinations are fed at a rate of 12 lbs/100 hens/d for 28 d (C:WM limit and C:SH limit), and two combinations are full fed the first 7 d, then fed at a rate of 12 lbs/100 hens/d for Days 8 to 28 (C:WM combo and C:SH combo). All the combination diets are 47% corn with either 47% wheat middlings or 47% soybean hulls plus vitamins and minerals. The partial results of this study shows that the hens which were limit fed the corn:soybean hulls combination diets went out of production the soonest (data not shown).
How to Use a Non-Feed Withdrawal Molt
Based on the work that we and others have done, the use of non-feed withdrawal molting programs has merit in the commercial laying hen industry. It is important to note that commercial producers who adopt such a molting program need to adapt it to their own situation and conditions. For example, different results would probably be obtained depending on the strain of birds used, the time of year the molt is done and many other factors. The price and availability of feed ingredients would also be a factor. However, in every situation, a standard type molting protocol should be followed. Thus, the following recommendations or guidelines are provided. On Day -7, the lights could be increased to 24 h per d and on that d approximately 100 to 125 hens from different locations in the house should be tagged and weighed. On Day 0, all previously fed layer feed should be removed from the feed troughs and the photoperiod reduced to 8 h per d. The molt feed diets should then be fed. On Day +7 and Day +14 the 100 to 125 hens should be weighed. On Day 21, the lights should be increased to 12 h per d, then on Day 28, the hens should be switched from the molt feed to a layer diet. Hens on this program should still lose about 15% of their starting body weight and egg production should approach between 0 and 5% during this period. Two example molt diets which might be considered in a non-feed withdrawal molt program are depicted in Table 7.
Examples of Using a Non-Feed Molting Program in Industry
From direct conversations with several egg production companies, different techniques have been implemented depending on their conditions. The first company fed a pre-molt diet 1 wk prior to starting, then on Day 1 they switched to feeding 57% corn and 40% wheat middlings at a rate of 10-12 lbs per 100 hens for 28 d. With this program they achieved good postmolt performance results. The second egg producer said that they were feeding a 60% wheat middlings:40% corn molt diet. They commented that postmolt egg production was similar to using a fasting method and mortality was lower than the fasting method. However, they commented that reduced egg shell quality occurred during the last 10 wk of the second cycle. This company plans to initiate their molting program at an earlier age.
Commercial Application of Non-Feed Withdrawal Molting Programs
In the summer of 2004, the UEP conducted a survey of 46 companies to determine what type of molting program they were using (Table 8) [16]. Of those surveyed, 22 said that they used a feed withdrawal program and 24 said they used non-feed withdrawal program. Of those producers who have tried a non-feed withdrawal molt program about 80% said they would continue using some type of non-feed withdrawal program. Most of the producers using the non-feed withdrawal program adapted their program using some variation of the methods we and others have done. Most of the programs used a combination of wheat middlings, soybean hulls, and corn as the molt diets. In general, most companies reported that slightly lower egg production occurred with a non-feed withdrawal program compared to a feed withdrawal program, however, the non-feed withdrawal program produced lower mortality with comparable egg shell quality.
United Egg Producers (UEP) Molting Guidelines
Due to the egg industry adoption of the findings of ours and other university research projects for non-feed withdrawal molting programs, the UEP’s scientific advisory committee modified their recommended molting guidelines in February 2005. Based upon those guidelines, the UEP amended the “Animal Husbandry Guidelines for U.S. Egg Laying Flocks” which is listed below:
1. Only non-feed withdrawal molt methods will be permitted after January 1, 2006.
2. The hens should be able to consume nutritionally adequate and palatable feed suitable for a non-producing hen.
3. Body weight loss should be sufficient so as not to compromise hen welfare.
4. Mortality during the molt should not substantially exceed normal flock mortality.
5. Water must be available at all times.
6. Reduce light period to no less than 8 h in closed houses or to natural day length in open houses for the duration of the rest period. When the flock is placed back on a layer diet, lights should be returned to the normal layer program.
It is interesting to note that the failure of an Animal Care Certified egg production company to meet the above guidelines will result in a failed audit in the audit year 2007. It is also interesting to note that these guidelines will apply to approximately 82% of the U.S. egg industry.
CONCLUSIONS AND APPLICATIONS
1. Based on experiments evaluating non-feed withdrawal molting techniques, it is apparent that using molt diets containing wheat middlings or soybean hulls in combination with corn would be feasible as an alternative molting program compared to using a feed withdrawal program.
2. The exact combination of wheat middlings or soybean hulls with corn has truly not been firmly established yet.
3. Based on the 2004 UEP molt survey, egg production companies have successfully adapted the non-feed withdrawal molting programs that researchers have developed to their own specific circumstances.
REFERENCES AND NOTES
1. Brake, J.T., and J.B. Carey. 1983. Induced molting of commercial layers. North Carolina Agricultural Extension Service Poultry Science and Technical Guide No. 10. North Carolina Agricultural Extension Service, Raleigh, NC.
2. Ruszler, P.L. 1996. The keys to successful force molting. Virginia Cooperative Extension Service, Publication 408-026 (revised), Blacksburg, VA.
3. Park, S.Y., S.G. Birkhold, L.F. Kubena, D.J. Nisbet, and S.C. Ricke. 2004. Effects of high zinc diets using zinc propionate on molt induction, organs, and postmolt egg production and quality in laying hens. Poult. Sci. 83:24-33.
4. Davis, A.J., M.M. Lordelo, and N. Dale. 2002. Use of cottonseed meats in molting programs. J. Appl. Poult. Res. 11:175-178.
5. Keshavarz, K., and F.W. Quimby. 2002. An investigation on different molting techniques with an emphasis on animal welfare. J. Appl. Poult. Res. 11:54-67.
6. Scheideler, S.E., M.M. Beck, and L. LaBrash. 2003. Non-feed withdrawal programs for laying hen molt. Proc. of 2003 Midwest Poultry Federation Convention, pages 50-53.
7. Anderson, K.E. 2003. The heterophil: lymphocyte ratio and behavioral response of present day SCWL laying hens during the first cycle and molt. Final Report to United Egg Producers.
8. Bell, D.D., and D.R. Kuney. 2004. Farm evaluation of alternative molting procedures. J. Appl. Poult. Res. 13:673-679.
9. Hooge, D.M., R.F. Wideman, and W.J. Kuenzel. 2005. License granted for new molting technology. Feedstuffs, January 24, page 6.
10. Funding for our research reported herein has come from the United Egg Producers, California Egg Commission, Ridley Feed Ingredients, Purina Mills, and the Midwest Poultry Consortium.
11. Biggs, P.E., M.W. Douglas, K.W. Koelkebeck, and C.M. Parsons. 2003. Evaluation of nonfeed removal methods for molting programs. Poult. Sci. 82:749-753.
12. Steel, R.G.D., and J.H. Torrie. 1980. Principles and Procedures of Statistics: A Biometrical Approach. 2nd ed. McGraw-Hill Book Company, New York, NY.
13. Urner Barry’s Price Current. 2000. Midwest egg price quote.
14. Biggs, P.E., M.E. Persia, K.W. Koelkebeck, and C.M. Parsons. 2004. Further evaluation of nonfeed removal methods for molting programs. Poult. Sci. 83:745-752.
15. Urner Barry’s Price Current. 2001. Midwest egg price quote.
16. Bell, D.D. 2004. United Egg Producers molt method survey. Personal Communication.
17. National Research Council. 1994. Nutrient Requirements of Poultry. 9th rev. ed. National Academy Press, Washington, DC.
ACKNOWLEDGEMENTS
The authors would like to acknowledge the work of Robert Leeper (deceased), Chet Utterback, and Steve Heffernan for their daily management of the birds and data collection.
TABLE 1. Composition of experimental molt diets and layer diet (Study 1) | |||
Ingredients and analysis | Corn molt diet | Wheat middlings molt diet | Layer diet |
——————————–(%)——————————— | |||
Ground yellow corn
WM1 Soybean meal (dehulled) Limestone Meat and bone meal2 Dicalcium phosphate Iodized salt Trace mineral mix3 Vitamin premix4 Calculated analysis5: Crude protein (%) MEn (kcal/kg) Calcium (%) Av. phos. (%) |
94.70
0.00 0.00 4.00 0.00 0.65 0.30 0.15 0.20 8.10 3,172.00 1.68 0.20 |
0.00
95.35 0.00 4.00 0.00 0.00 0.30 0.15 0.20 14.30 1,900.00 1.63 0.28 |
68.70
0.00 18.40 8.50 2.50 1.25 0.30 0.15 0.20 16.00 2,865.00 3.80 0.45 |
1WM = wheat middlings.
2Meat and bone meal = 50% protein, pork meal, source from Effingham FS, Effingham, IL.
3Provided per kilogram of diet: manganese, 75 mg from manganese oxide; iron, 75 mg from iron sulfate; zinc, 75 mg from zinc oxide; copper, 5 mg from copper sulfate; iodine, 0.75 mg from ethylene diamine dihydroiodide; selenium, 0.1 mg from sodium selenite.
4Provided per kilogram of diet: vitamin A from vitamin A acetate, 4,400 IU; cholecalciferol, 1,000 IU; vitamin E from a-tocopheryl acetate, 11 IU; vitamin B12, 0.011 mg; riboflavin, 4.4 mg; d-pantoghenic acid, 10 mg; niacin, 22 mg; menadione sodium bisulfite complex, 2.33 mg.
5Based on NRC (1994) feed composition tables [17].
TABLE 2. Effect of non-feed vs feed withdrawal molting methods on subsequent egg production (Study 1) | ||||
Days to 50% production | Peak hen-day production | Egg production
(wk 5-44) (wk 1-44) |
||
(days) | (%) (wk) | ——–(%H-D)——– | ||
Corn
WM1 4-d feed withdrawal, then corn 10-d feed withdrawal, then corn Pooled SEM |
49
43 50 47 – |
84.3 (12)
89.6 (14) 85.4 (15) 90.7 (14) – |
66b
74ab 68b 77a 1.6 |
61b
68ab 62ab 70a 1.7 |
a,bMeans within a column with no common superscript differ significantly (P < 0.05).
1WM = wheat middlings. |
TABLE 3. Effect of non-feed vs feed withdrawal molting methods on egg income minus feed costs (wk 1 to 44) (Study 1) | ||||
Treatment | Egg income1 | Feed cost | Profit | Profit per hen-housed |
($) | ($) | ($) | ($) | |
Corn
WM2 4-d feed withdrawal, then corn 10-d feed withdrawal, then corn |
838.72
991.78 880.02 1016.69 |
330.14
343.52 337.76 351.33 |
508.58
648.26 542.26 665.36 |
6.05
7.72 6.46 7.92 |
1Based on $.70 per dozen produced (Urner Barry Price Current, midwest grade A large white eggs) [13].
2WM = wheat middlings. |
TABLE 4. Composition of experimental molt diets (Study 2) | ||||||
Ingredients and analysis | Corn | Wheat middlings | Corn gluten feed | Distiller’s dried grains | 71% WM:23% corn | 47% WM:47% corn |
—————————-(%)—————————- | ||||||
Corn
WM1 Corn gluten feed DDGS2 Limestone Dicalcium phosphate Iodized salt Mineral mix3 Vitamin mix4 Insecticide5 Calculated Analysis6: Crude protein (%) MEn (kcal/kg) Calcium (%) Av. phos. (%) |
93.68
— — — 4.67 — 0.30 0.15 0.20 0.05 8.0 3,138 2.0 0.25 |
—
94.34 — — 4.87 0.38 0.30 0.15 0.20 0.05 14.2 1,887 2.0 0.28 |
—
— 95.00 — 4.20 0.10 0.30 0.15 0.20 0.05 20.0 1,663 2.0 0.25 |
—
— — 94.46 4.84 — 0.30 0.15 0.20 0.05 25.9 2,343 2.0 0.37 |
22.99
71.25 — — 4.96 0.10 0.30 0.15 0.20 0.05 12.6 2,195 2.0 0.25 |
47.05
47.00 — — 4.87 0.38 0.30 0.15 0.20 0.05 11.1 2,516 2.0 0.25 |
1WM = wheat middlings.
2DDGS = distillers dried grains with solubles.
3Provided per kilogram of diet: manganese, 75 mg from manganese oxide; iron, 75 mg from iron sulfate, zinc, 75 mg from zinc oside; copper, 5 mg from copper sulfate; iodine, 0.75 mg from ethylene diamine dihydroiodide; selenium, 0.1 mg from sodium selenite.
4Provided per kilogram of diet: vitamin A from vitamin A acetate, 4,400 IU; cholecalciferol, 1,000 IU; vitamin E from a-tocopheryl acetate, 11 IU; vitamin B12, 0.011 mg; riboflavin, 4.4 mg; D-pantothenic acid, 10 mg; niacin, 22 mg; menadione sodium bisulfite complex, 2.33 mg.
5Commercially available insecticide.
6Based on NRC (1994) feed composition tables [17].
TABLE 5. Effect of non-feed vs. feed withdrawal molting treatments on hen-day egg production during the 4-wk molt period and 40 wk postmolt (Study 2) | ||||||
Week | ||||||
Treatment | 1 | 2 | 3 | 4 | 1 to 4 | 5 to 44 |
————————(%)————————- | ||||||
10-d feed withdrawal, 16% CP
10-d feed withdrawal, corn Corn WM1 71% WM1:23% corn 47% WM1:47% corn Corn gluten feed DDGS2 Pooled SEM |
25d
25d 55a 37c 44b 52a 44b 58a 2.2 |
0d
0d 20b 7cd 13bc 19b 9c 31a 2.9 |
0d
0d 7c 11bc 11bc 14b 8c 27a 1.8 |
9bc
0d 5cd 11bc 16b 12bc 11bc 29a 2.6 |
8e
6e 22bc 16d 21bcd 24b 18cd 36a 1.8 |
71a
68a 64a 67a 70a 62a 67a 64a 2.4 |
a-eMeans within a column with no common superscript differ significantly (P < 0.05).
1WM = wheat middlings.
2DDGS = distillers dried grains with solubles.
TABLE 6. Effect of non-feed vs feed withdrawal molting methods on egg income minus feed costs (wk 1 to 44) (Study 2) | ||||
Treatment | Egg income1 | Feed
cost2 |
Profit | Profit per hen-housed |
——————-($)——————- | ||||
Corn
WM3 WM3/corn (47:47%) WM3/corn (71:23%) Corn gluten feed DDGS4 10-d feed withdrawal, then 16% corn-soybean 10-d feed withdrawal, then 8% corn |
662.90
690.25 624.10 718.95 682.55 676.35 719.00 650.75 |
286.98
277.67 285.81 282.10 264.66 275.26 281.61 277.07 |
375.92
412.58 338.29 436.85 417.89 401.09 437.39 373.68 |
5.22
5.73 4.70 6.07 5.80 5.57 6.08 5.19 |
1Based on $.60 per dozen produced (Urner Barry Price Current, midwest grade A large white eggs [15]).
2Molt plus layer feed costs. 3WM = wheat middlings. 4DDGS = distillers dried grains with solubles. |
TABLE 7. Example molt diets for a non-feed withdrawal program | ||
Molt diets | ||
Ingredients | Wheat middlings/corn (71:23%) | Soybean hulls/corn (47:47%) |
—————-(Pounds Per Ton)—————- | ||
Corn
WM1 Soybean hulls Limestone Dicalcium phosphate Salt Mineral mix Vitamin mix Insecticide2 |
460
1425 – 99 2 6 3 4 1 |
942
– 942 82 20 6 3 4 1 |
1WM = wheat middlings.
2Commercially available insecticide. |
TABLE 8. UEP molt survey (Summer, 2004) | |||
Frequency of response1 | |||
Parameter | Higher | Lower | Same |
——————(% of total companies)—————– | |||
Mortality
Egg Production Egg Quality |
4.2
8.3 Better 8.3 |
54.2
41.7 Worse 20.8 |
41.7
50.0 70.8 |
1Responses come from commercial egg companies and independent egg producers and represent the evaluation of non-feed withdrawal molting methods compared to a conventional feed withdrawal molting technique [16].
CAPTION FOR FIGURE
FIGURE 1. Hen-day egg production for Days 1 to 28 (Study 1). Treatment 1 (■) fed corn molt diet. Treatment 2 (●) fed wheat middlings diet. Treatment 3 (◆) feed withdrawn for 4 days. Treatment 4 (▲) feed withdrawn for 10 days.
[1] To whom correspondence should be addressed: kkoelkeb@uiuc.edu