2016 SOUTHERN POULTRY SCIENTIFIC FORUM

The effect of pasture vs indoor rearing on the breast filet shelf-life of commercial-meat chickens and alternative breeds
M. Bear, G. Rentfrow, J. Jacob, A. Pescatore, T. Fisher, M. Paul, M. Ford
This study looked at the effect of pasture-rearing on breast filet shelf-life of commercial-type meat chickens (BR) and three alternative breeds, Rhode Island Red (RIR), Barred Plymouth Rock (BPR) and Black Australorp (BA). All chickens received the same diets (2866 kcal/kg and 19.2% CP) throughout the study. All the alternative breeds started on the floor at the same time and half placed on pasture at 4 weeks of age. To adjust for the expected faster growth rate, the BR were started on the floor 7 weeks later and half placed on pasture at 3 weeks of age. The study was a 4 x 2 factorial design with 4 breeds raised with or without pasture. There were 3 replications of 24 chicks per treatment. All chicks were placed straight run and weights adjusted for differences in sex ratios at the end of the 14 week trial. As expected, the BR were ready to harvest at 7 weeks of age while the other breeds required 14 weeks and still weighed significantly less. At the end of the trial 1 male and 1 female from each replication for each of the treatments. Whole carcasses were ice chilled then the right breast filets were removed. Breast filets were frozen (-20°C) until analysis could be performed. Breast filets were allowed to thaw (48h; 4°C) before the breast filet shelf-life was determined. The filets were placed of a styrofoam tray, PVC overwrapped, and displayed in a retail window case (4°C) under constant cool white florescent lighting (1300 LUX) for 7d. To determine lipid peroxidation, 2-Thirobarbituric Acid Reactive Substances (TBARS) were measured on a 3 gm samples removed longitudinally from each breast filet and then rewrapped on d 0, 3, and 7. No differences were detected (p>0.05) between sex, breed or days of retail display within pasture vs those raised without pasture. Data was pooled to compare pasture vs non-pasture shelf-life. Pasture-raised chickens had lower TBARS values at d 0 and 7 (p<0.001). These data suggest that pasture-raised chickens have lower breast lipid peroxidation during 7 days for retail display which may transfer into increased shelf life.

FIELD OBSERVATIONS: Insect populations on mixed grasses versus alfalfa pastures
J. Jacob, B. Newton, A. Pescatore, H.D. Gillespie, S. Dasgupta
One of the perceived benefits of pasturing poultry is access to a variety of insects that the birds are able to consume to supplement a mixed feed. The observations reported here are from sweep net collections from three sites on a grass or alfalfa field on two different dates during the same summer. For the first collection the sites were 10 ft x 10 ft, but the area was expanded to 15 ft x 15 ft for the second collection. The collections were frozen and later identified by an entomologist and sorted by taxonomical order. For both the grass and the alfalfa the main insects identified were from the order Hemiptera and more so in the alfalfa (32.8% for grass plots and 89.2% for the alfalfa), although they varied in suborder grouping. For the grass, the majority of insects in the order Hemiptera were from the suborder Auchenorrhyncha (free-living insects) while for the alfalfa the majority of the insects were divided between the Suborder Heteroptera (true bugs) and Auchenorrhyncha. The grass had the highest number of insects collected (610 in the grass and 408 in the alfalfa). The grass also had the highest number of spiders collected (44 in grass versus 1 in the alfalfa). The results confirm earlier observations that insect populations vary depending on the pasture crop but in this study the grass had more insects and spiders (654) than the alfalfa (409). The observations confirm that different pasture crops will attract different insects and spiders. The number of insects and spiders varied between days (1.3/sq ft in the first collection and 34.9/sq ft in the second for the grass and1.0/sq ft in the first collection and 20.5/sq ft in the second for the alfalfa). The low collection of insects in the first collection vs. the second collection illustrates the seasonality of insect populations; therefore, pasture poultry producers cannot depend on insect consumption as a significant nutrition source for their birds.

FIELD OBSERVATIONS: Effect of pasture crop selection on insect population
J. Jacob, B. Newton, A. Pescatore, H.D. Gillespie, S. Dasgupta
A commonly asked question from free-range poultry producers is “Which crop should I use?” Two factors to consider include the nutrients obtained from the plants as well as the nutritional value of the insects attracted to that crop. This study pertained to the latter factor and looked at what insects are attracted to different pastures typically selected for pasture poultry production. There were three pasture treatments, each with three sites of 1,000 ft2. The treatments included legumes (Crimson clover, Birdsfoot trefoil, and Alfalfa), grasses (Ryegrass, Bromegrass, and Tall fescue), and a combination of the legumes and grasses previously indicated. Sweep net collections of 225 ft2 areas within each plot were conducted. The collected items were frozen and later identified by an entomologist. The insects and spiders collected were sorted by taxonomical order. The collections from the three sites for each treatment were combined and compared. The plots with legumes had the most insects (231) with the grasses the least (123). The combination of legumes and grasses were in between (166). For all the pastures, insects from the order Hemiptera were the most predominant (76.6%, 60.2%, 72.9% for the legumes, grasses and combination plots, respectively). This includes insects that have a proboscis and capable of sucking sap from plants and would include the cicadas, aphids, plant hoppers, leaf hoppers and shield bugs. A similar finding occurred with the spiders with 21, 47 and 35 spiders identified in the legumes, grasses and combination plots, respectively. These observations indicate that different pasture crops will attract different insects. Similar observations are required to confirm the findings, and to see how the populations were distributed in similar pasture crops in different locations at different times of the year. The low number of insects and the variability between pasture types indicate that insect populations are not a reliable nutrition source for pasture poultry.

Carcass traits of heritage chicken breeds using sorghum and field peas to replace corn and soybean meal in diets
T. Fisher, A. Pescatore, J. Jacob, A. Cantor, M. Ford, T. Ao.
The objective of this study was to evaluate the carcass yield and composition of Rhode Island Reds (RIR) and Barred Plymouth Rocks (BPR) using alternative feed ingredients (sorghum and field peas). A 2 x 5 factorial arrangement of breeds and dietary treatments was used with the following diets: 1) a CSM-based control, 2) 100% of corn and 20% of soybean meal in CSM diet replaced with sorghum (SSM), 3) SSM diet with a dietary enzyme complex (Allzyme® SSF, Alltech Inc.) added at 0.02% of diet (SSM+), 4) complete replacement of CSM with a 2:1 ratio of field peas to sorghum (SFP), and 5) SFP diet with Allzyme® SSF added at 0.02% of diet (SFP+). Replacement of soy limited dietary protein levels; therefore, CSM contained 20% CP, SSM/SSM+ contained 18.5% CP, and SFP/ SFP+ contained 15.3% CP. Birds were housed in floor pens at 0.2 m2/bird with diet and water provided on an ad libitum basis. At 98 days of age, two male birds per pen were processed and the carcasses were chilled for at least two hours. The parameters measured at processing included live weight, chilled WOG weight, part weights (boneless skinless breasts, tenders, leg quarters, and wings), and breast meat color. Live weight did not differ between breeds, but it differed significantly among diets. The live weight of birds fed CSM was similar to those fed SSM or SSM+ (2017 g); however, birds fed CSM were significantly heavier than birds fed SFP or SFP+ (2088 vs. 1860 g, P<0.05). As a percentage of live weight, the chilled WOG weights (70.4%) were similar among breeds and diets. As a percentage of the chilled WOG weight, there were no significant (P>0.05) differences in relative parts weights. The breast meat of RIR birds was yellower than the BPR breast meat (2.82 vs. 1.93; P<0.05), but there was no significant difference between breeds for lightness or redness. A significant (P<0.05) dietary effect was also noted – as corn and soybean meal were reduced in the diet, lightness and yellowness of the breast meat decreased while redness increased. No breed x diet interactions were noted for the parameters measured. In conclusion, the use of sorghum and field peas with or without a dietary enzyme complex to replace corn and soybean meal may reduce the live weight and alter the breast meat color of heritage breeds, but it does not affect their carcass composition.

2015 POULTRY SCIENCE ASSOCIATION MEETING

Use of sorghum and field peas to replace corn and soybean meal in diets for heritage chicken breeds
T. Fisher, A. Pescatore, J. Jacob, A. Cantor, M. Ford and T. Ao
This study evaluated the use of sorghum and field peas as replacements for corn and soybean meal in diets for 2 heritage breeds: Rhode Island Red (RIR) and Barred Plymouth Rock (BPR). A 2 × 5 factorial arrangement of breeds and dietary treatments was used with the following diets: (1) a CSM-based control, (2) 100% of corn and 20% of soybean meal in CSM diet replaced with sorghum (SSM), (3) SSM diet with a dietary enzyme complex (Allzyme SSF, Alltech Inc.) added (SSM+), (4) complete replacement of CSM with a 2:1 ratio of field peas to sorghum (SFP), and (5) SFP diet with Allzyme SSF added (SFP+) . Replacement of soy limited dietary protein levels; therefore, CSM contained 20% CP, SSM/SSM+ contained 18 .5% CP, and SFP/SFP+ contained 15 .3% CP. Three replicate groups of 11 straight-run chicks per treatment were housed in floor pens at 0.2 m2/bird. Diets and water were provided on an ad libitum basis. Body weight and feed intake were monitored until birds were processed at 98 d. Before analysis, all values were corrected for the ratio of males:females in the pen . At processing, RIR birds were heavier than BPR birds (1,775 vs 1,668 g, P < 0 .01) and a breed × diet interaction was noted – RIR birds fed SSM diets were heavier (P < 0 .05) than BPR birds fed those same diets. However, ADFI (70 .5 g/bird/d) and feed:gain (4 .2 g feed/g gain) were similar between the breeds . To account for differences in diet composition, dietary effects were analyzed on a nutrient intake to gain basis. Feed:gain for birds fed CSM, SSM, and SSM+ (3.8 g feed/g gain) was significantly (P < 0 .01) better than for birds fed SFP or SFP+ (4 .7 g feed/g gain) . A similar pattern was observed for energy intake to gain. No significant differences were observed for protein intake to gain, but birds fed SSM diets consumed less methionine than birds on other diets. In conclusion, total replacement of CSM with sorghum and field peas reduced bird performance. However, sorghum replaced corn and partially replaced soy without detrimental effects for one of the breeds. This breed interaction indicates a possible difference in dietary requirements between breeds.

2015 SOUTHERN POULTRY SCIENTIFIC FORUM

Effects of alternative feedstuffs and dietary enzyme on the performance of alternative breeds of chickens
T. Fisher, A. Pescatore, J. Jacob, A. Cantor, M. Ford, T. Ao
This study was conducted to evaluate the replacement of corn and soybean meal (CSM) with alternative feedstuffs and dietary enzyme on the performance of straight-run commercial broilers (Cobb700) and two alternative breeds of chickens: males from a Black Sex-Link cross (BSL) and straight-run Rhode Island Reds (RIR). Each breed was fed five diets using a 3 x 5 factorial arrangement of treatments. The following isocaloric (2000 kcal AMEn/kg) and isonitrogenous (20% CP) diets were used: 1) CSM based diet; 2) ~30% of CSM in diet 1 replaced with field peas; 3) Diet 2 + Allzyme SSF (Alltech Inc.); 4) ~50% of CSM in diet 1 replaced with a mixture of field peas, buckwheat, and flax seed; 5) Diet 4 + Allzyme SSF. For each treatment, three replicate groups of 12 chicks were housed in floor pens at a density of 0.19 m2/bird. Diets and water were provided on an ad libitum basis. ADG, ADFI and feed:gain ratio (F:G) were monitored from 1 d of age until processing (42 d for broilers and 96 d for BSL and RIR). At processing, average BW was 1994 g for broilers, 1860 g for BSL males, and 1577 g for RIR birds. Broilers had higher (P<0.01) overall ADG (37.5 vs. 17.6 vs. 14.9 g/bird/d) and lower (P<0.01) F:G (2.3 vs. 4.2 vs. 4.4) compared with the BSL males and RIR birds respectively. BSL males had higher (P<0.05) ADG (17.6 vs 14.9 g/bird/d) and ADFI (75.8 vs. 65.4 g/bird/d) compared with RIR birds, while F:G was similar for both breeds. Replacing 30% of the CSM with field peas did not alter performance of chicks. Replacing 50% of the CSM with field peas, buckwheat and flax seed reduced (P<0.05) ADG (21.0 vs. 24.6 g/bird/d) and increased (P<0.05) ADFI (87.1 vs. 71.6 g/bird/d) resulting in poorer (P<0.05) F:G (4.6 vs. 3.3). These negative effects were alleviated by adding Allzyme SSF. No breed x diet interactions were observed. In summary, broilers had better growth performance than BSL males and RIRs. For all three breeds, field peas replaced 30% of the CSM diet without reducing performance. However, a 50% replacement of CSM with field peas, buckwheat, and flax seed resulted in reduced performance that was mitigated by adding Allzyme SSF.

2014 POULTRY SCIENCE ASSOCIATION MEETING

Growth and nutrient intake patterns of meat-type strains and heritage breeds of chickens using a self-selection feeding program
T.M. Fisher, A.J. Pescatore, J.P. Jacob, M.A. Paul, M. van Benschoten, L.R. Good, A.H. Cantor and M.J. Ford
The objective of this study was to model nutrient intake patterns and growth performance of different types of chickens when given a selfselection feeding program. Birds used were 3 meat-type birds (Cornish Cross males, Cornish Cross females, Red Ranger males) and males of 3 heritage breeds (Rhode Island Red, Barred Plymouth Rock, and Black Australorp). For each type of bird, 3 replicate groups of 25 chicks, 1 d of age, were randomly assigned to floor pens at 929 cm2/bird. All chicks received a complete diet for the first 14 d, and then were given a cafeteria-style self-selection feeding program consisting of 4 feed choices provided on ad libitum basis. Feed choices included a protein concentrate (39% CP) without added methionine and 3 grains (cracked corn, naked oats, and pearl millet) that were similar in energy content, but differed in protein content. Feeds were randomly allocated to 4 identical feeders within each pen. Two to 3 times per week, consumption for each feeder was recorded and the feeder locations were rotated. Body weight was recorded weekly. Linear and nonlinear models were constructed to describe the growth and nutrient intake patterns for each type of bird from 3 wk of age to processing at a BW of 2,300 g. All of the linear models for growth vs. time provided a good fit to the data (R2 = 0.98–0.99). Models for the meat-type birds had significantly steeper slopes than those for the heritage breeds (P < 0.01). At any given age, the meat-type birds were heavier than the heritage breeds (P < 0.01). Intake of feed, kcal of ME, CP, and methionine all showed linear relationships to BW for meat-type birds (R2 = 0.78–0.95) and a quadratic (P < 0.01) relationship to BW for the heritage breeds (R2 = 0.96). At any given BW, the meat-type birds consumed more energy, CP, and Met than the heritage breeds (P < 0.01). At any given feed intake, the meat-type birds consumed less energy, more CP, and more methionine than the heritage breeds (P < 0.01). Based on self-selection, the growth and nutrient intake patterns varied among the different types of chickens and should be considered when rearing these heritage breeds.

Evaluation of the methionine requirement for three dual-purpose chicken breeds
J.P. Jacob, A.J. Pescatore, A.H. Cantor, T.M. Fisher, and M.J. Ford
Methionine (Met) is typically the limiting amino acids in poultry diets. To meet the dietary methionine requirement without over feeding total protein synthetic Met is added to commercial poultry diets. Limited levels of synthetic Met are currently allowed in organic poultry diets in the United States, with the plan to prohibit it completely in the future. There has been some speculation that dual-purpose breeds have lower Met requirements making them an alternative breed for use in organic chicken meat and egg production. This study looked at the Met requirement of 3 alternative breeds – Black Australorp (BA), Rhode Island Red (RIR) and Black Plymouth Rock (BPR). There were 4 dietary treatments with Met levels analyzed as 0.31, 0.36, 0.48 and 0.52% Met in a low density diet (3,047 kcal of ME/kg of diet). There were 5 replications per diet and breed combination with 10 chicks (straight run) per replication. The feed was available ad libitum for 4 wk and the body weight and feed consumption measured daily and feed efficiency calculated. At placement the RIR chicks were statistically larger than the BA and BPR chicks but the lowest at wk 1. There were no significant differences in body weight for the remainder of the trial. There were no significant differences in feed efficiency with regards to breed or diet. There was no significant effect of Met level on body weight or feed efficiency. At 4 wk of age, chicks from all breeds reached body weights of 300 g and overall feed efficiency of 2.48. The level of 0.31% Met of diet 1 was the lowest level of dietary Met that could be achieved with the corn/ soybean meal low-density diets. Typical Met requirements range from 0.28% for brown egg layers and 0.50% for broilers. The growth and feed efficiency achieved in this study indicated that for dual purpose breed chicks, the Met requirement for a diet containing 3,047 kcal of ME/kg is less than 0.31%. Unfortunately the poor overall performance of the dual purpose breeds does not make them an economically viable alternative for organic chicken meat production. However, they may be necessary if synthetic Met cannot be added in the future.

2014 SOUTHERN POULTRY SCIENTIFIC FORUM

Potential of alternative egg producing breeds for small-scale poultry production
J. Jacob, A. Pescatore, T. Fisher, M. Ford, A. Cantor, M. Paul, M. van Benschoten, L. Good
Many small-scale egg producers, especially those raising hens on pasture, are looking for alternatives to the commercial brown-shelled egg laying breeds. A study was conducted to assess the production potential of the dual breeds Rhode Island Reds (RIR), Barred Plymouth Rocks (BPR), and Black Australorps (BA) compared to a commercial brown layer (ISA), a black-sex link (BSL) and a red sex-link (RSL). Pullet chicks were fed a starter broiler diet for the first 2 weeks and then fed cafeteria-style till 20 weeks of age. At 20 weeks of age 65 pullets per breed were randomly assigned to one of five pens per breed, and placed on a layer feed. During a 28 week production cycle average egg production and egg weight were determined in 4 week periods. The ISA Browns out performed all the other breeds. The hens peaked higher and maintained egg production longer than any of the other breeds. Over the 28 weeks of production, the ISA hens average 85.2% Hen-Day (HD) egg production. The RSL and BSL hens averaged only 69.3 and 70.8%, respectively. The RIR and BPR were similar to the sex-link crosses with 70.9 and 65.6% production, respectively. The BA hens were the poorest producers, averaging only 59.4% production. Egg size was also higher for the ISA hens. The ISA hens produced larger eggs throughout the study, averaging 64.9 g. The BSL and RSL average 57.5 and 56.5 g, respectively. The RIR were similar to the sex-link crosses with an average egg weight of 56.7 g. The BPR and BA produced the smallest eggs with 53.8 and 54.8 g, respectively. At the end of the 28 week trial, the BPR hens were the heaviest at 2342 g and the ISA hens weighed the least at 1922 g. The RSL and BSL hens weighed more than the ISA at 2108 and 2340 g, respectively. The RIR and BA hens weighed 2089 and 2208 g, respectively. While the ISA hens out performed all the other hens in the study, it is possible that the alternative breeds will do comparatively better in a pasture production system which is commonly used with small-scale poultry production.

Grain preferences of alternative breeds used for meat production determined through a self-selection feeding program
T. Fisher, A. Pescatore, J. Jacob, M. Paul, M. van Benschoten, L. Good, A. Cantor, M. Ford
This study was conducted to determine the grain preferences of alternative chicken breeds/strains used for meat production. Seventy-five dayold chicks from each of six breeds/strains (Cornish Cross males (CCM), Cornish Cross females (CCF), Red Ranger males (RR), and males from three heritage breeds: Rhode Island Red (RIR), Barred Plymouth Rock (BPR), and Black Australorp (BA)) were divided into three replicate groups and randomly assigned to floor pens at 929 cm2/bird. The chicks received a complete diet for two weeks, and were then transitioned to a self-selection feeding program with four feed choices fed ad libitum: a 39% CP protein concentrate, cracked corn, rolled naked oats, and pearl millet. The feeds were randomly allocated to four identical feeders within each pen and the feeders were rotated 2-3 times per week. Grain preferences were calculated for each breed/strain over two body weight periods: 1) 500 to 1500g and 2) 1500 to 2300g. Differences were considered significant at p<0.05. Averaged over the two BW periods, BPR consumed significantly more cracked corn than either pearl millet or naked oats. BA followed the same pattern, except they consumed significantly less naked oats during the first BW period. RR and RIR showed a significant preference for cracked corn and pearl millet over naked oats during the first BW period. During the second BW period, RR and RIR showed a significant preference for pearl millet over cracked corn, with extremely low consumption of naked oats. CCM showed a significant preference for cracked corn over naked oats during the first BW period, but pearl millet was not significantly different from the other grains. However, in the second BW period, CCM showed a significant preference for cracked corn over both pearl millet and naked oats. CCF preferred cracked corn over the other grains during both BW periods, with a significant difference between pearl millet and naked oats during the second BW period. Overall, cracked corn was the grain of choice for four of the six breeds/ strains during both BW periods, pearl millet was preferred by RR and RIR during the second BW period, and naked oats were the least preferred for all breeds/strains. These grain preferences, which differed between growth periods and among breeds/strains, should be considered when formulating diets for alternative breeds/strains.

2013 POULTRY SCIENCE ASSOCIATION MEETING

Growth performance, nutrient and energy intake of alternative breeds used for meat production provided through the use of a self-selection feeding program
T.M. Fisher, A.J. Pescatore, J.P. Jacob, M.A. Paul, M. van Benschoten, L.R. Good, A.H. Cantor and M.J. Ford
This study was conducted to determine the nutrient and energy intake of alternative chicken breeds used for meat production through a selfselection feeding program. Seventy-five day-old chicks per breed/strain (Cornish Cross males (CCM), Cornish Cross females (CCF), Red Rangers males (RR), and males from 3 heritage breeds of Rhode Island Red (RIR), Barred Plymouth Rock (BPR), and Black Australorp (BA)) were divided into 3 replicate groups and randomly assigned to floor pens at a density of 929 cm2/bird. All chicks received a complete diet for the first 2 weeks, and then were transitioned to a self-selection feeding program using 4 feed choices provided on an ad libitum basis. The feed choices included a protein concentrate (39% CP) without added methionine and 3 grains that were similar in energy content, but differed in protein and methionine content (cracked corn, naked oats, and pearl millet). The feeds were randomly allocated to 4 identical feeders within each pen and the location of the feeders was rotated 2–3 times per week. All birds were grown to 2300 g. CCM, CCF, RR, and the heritage breeds reached this weight at 7, 8, 9, and 20 weeks respectively. During the self-selection feeding program, the average daily gain was 51.0, 45.1, 35.2, and 10.5 g/bird/day for CCM, CCF, RR, and the heritage breeds respectively (P < 0.0001). The heritage breeds had a significantly poorer (P < 0.0001) feed efficiency (feed/gain = 5.79) than CCM (2.00), CCF (2.07), and RR (2.56). CCM, CCF, and RR selected diets lower in energy (2887 vs. 2950 vs. 2982 vs. 3068 kcal/kg, P < 0.0001), and higher in protein (20.8 vs. 19.2 vs. 18.3 vs. 16.2%, P < 0.0001) than the heritage breeds. Methionine intake varied significantly (P < 0.0001) by breed/strain with CCM having the highest (0.32%), followed by the CCF and RR (0.31%), and was lowest in the heritage breeds (0.27%). Based on self-selection, the nutrient and energy intake varied by breed/strain and should be taken into consideration when formulating diets for alternative breeds/strains.

Growth performance, nutrient and energy intake of alternative breed replacement pullets provided through the use of a self-selection feeding program
T.M. Fisher, A.J. Pescatore, J.P. Jacob, M.A. Paul, M. van Benschoten, L.R. Good, A.H. Cantor and M.J. Ford
The objective of this study was to determine the nutrient and energy intake of alternative chicken breeds as replacement pullets through a self-selection feeding program. Seventy-five day-old chicks per breed/ strain (Rhode Island Red, Barred Plymouth Rock, Black Australorp, Black Sex-Link, Red Sex-Link, and ISA Brown) were divided into 3 replicate groups which were randomly assigned to floor pens at a density of 929 cm2/bird. All chicks received a complete diet for the first 2 weeks, and then were transitioned to a self-selection feeding program using 4 feed choices provided on an ad libitum basis. The feed choices included a protein concentrate (39% CP) without added methionine and 3 grains similar in energy content, but differing in protein and methionine content (cracked corn, naked oats, and pearl millet). The feeds were randomly allocated to 4 identical feeders within each pen and the location of the feeders was rotated 2–3 times per week. At 19 weeks of age, individual body weight averaged 1630 g for Red Sex-Link, 1623 g for Black Sex-Link, 1612 g for Black Australorp, 1565 g for Barred Plymouth Rock, 1523 g for ISA Brown, and 1444 g for Rhode Island Red pullets. The body weights of the Red Sex-Link, Black Sex-Link, and Black Australorp pullets were significantly different (P = 0.0026) from that of the ISA Brown and Rhode Island Red pullets. The body weights for the Barred Plymouth Rock pullets were significantly different from the Rhode Island Red pullets. Average daily feed intake (52.8 g/bird/ day) from placement (1d of age) through the end of the study was not significantly different among the breeds/strains (P = 0.27). Additionally, there were no significant differences in diet selection between breeds (P > 0.05). Free-choice feed selection for all breeds/strains resulted in a diet containing approximately 3098 kcal/kg, 15.4% protein, 0.26% methionine, 0.51% calcium, and 0.29% phosphorus. Self-selection resulted in diets that were sufficient in protein, methionine, and phosphorus, but lower in calcium and higher in energy than NRC requirements.

Carcass traits of alternative breed meat birds provided either a selfselected feeding program or a complete broiler starter diet
T M. Fisher, A.J. Pescatore, J.P. Jacob, M.A. Paul, M. van Benschoten, L.R. Good, A.H. Cantor and M.J. Ford
The objective of this study was to evaluate the carcass yield and composition of alternative chicken breeds/strains raised for meat production. Birds were raised on a self-selection feeding program that included a protein concentrate (39% CP) without added methionine and 3 grains that were similar in energy content, but differed in protein and methionine content (cracked corn, naked oats, and pearl millet). The breeds utilized were Cornish Cross males (CCM), Cornish Cross females (CCF), Red Rangers males (RR), and males from 3 heritage breeds (Rhode Island Red (RIR), Barred Plymouth Rock (BPR), and Black Australorp (BA)). Birds were processed when the average body weight for the breed/strain reached 2300 g. CCM, CCF, and RR reached this weight at 7, 8, and 9 weeks respectively. At 10 weeks of age, the heritage breeds had not yet reached target weight and were split into 2 groups – one remaining on self-selection and one placed on a complete broiler starter diet (3084 kcal/kg, 22% CP). The heritage breeds reached target weight at 20 weeks of age. The parameters measured at processing included live weight, WOG weight, part weights (boneless breasts with skin, whole legs, and wings), fat pad weight, and giblet weight. CCM and CCF had significantly higher WOG yields when compared with the other breeds/strains (73.7 vs. 67.5%, P < 0.0001). CCF had significantly higher boneless breast yields than CCM, and both had significantly higher yields than the other breeds/strains (25.4 vs. 23.0 vs. 13.0%, P < 0.0001). Conversely, leg and wing yields were lower for the CCM and CCF than for the other breeds/strains. As a percentage of live weight, liver weights were higher for the CCM, CCF, and RR than for the heritage breeds. CCM, CCF, and RR had significantly smaller gizzards than the heritage breeds on self-selection diets. Fat pad weight varied by breed with no consistent pattern. Heritage breeds switched to broiler starter had significantly smaller gizzards (1.92 vs. 2.28%, P = 0.0262) and smaller fat pads (0.94 vs. 1.77%, P = 0.0014) than those remaining on self-selection.