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SUMMARY Salmonella and Campylobacter are the two pathogens commonly associated with raw poultry meat, as poultry products are frequent vehicles of these bacteria. The objective of the current research was to determine the optimal contact time for 6 antimicrobial treatments, including water, 0.003% chlorine, 0.07% peracetic acid (PAA), 0.1% PAA, 0.35% cetylpyridinium chloride (CPC), and 0.6% CPC. Drumsticks (n = 192) were inoculated with Salmonella Typhimurium and Campylobacter jejuni, and allowing some bacterial attachment time, drumsticks were treated with the 6 antimicrobials mentioned above for 10, 20, and 30 s contact time. The recoveries of Salmonella Typhimurium and Campylobacter jejuni were determined after plating. The results of this study indicated the antimicrobial effect on reducing Salmonella and Campylobacter on poultry parts, and the impact of contact time on the efficacy. This could be a guide for industrial application of which antimicrobial to use and how to control the contact time.

SUMMARY The prevalence and severity of footpad dermatitis (FPD) and gait score (GS) as an indicator of lameness in commercial broiler production in the United States has not been widely reported. The objectives of this field study were to determine the prevalence and severity of FPD and lameness in commercial broilers, as well as the relationship between FPD and GS under the production conditions typical of the southeastern United States. Observations were collected from an integrated broiler complex producing a light broiler (1.94 to 2.22 kg) and an integrated broiler complex producing a heavier broiler (3.62 to 3.76 kg). Data were collected from 554 farms, 16,697 houses, and 166,977 broilers, representing over 328 million birds over the 3-year span of the study. Light broilers had significantly better FPD and GS than heavier broilers. Additionally, there was a strongly significant association between FPD and GS within a complex. There were significantly greater odds of GS worsening as FPD worsened and significantly high odds of FPD becoming more severe as GS worsened.

Flue gas desulfurization (FGD) gypsum may be a viable low-cost alternative bedding material for broiler production. In order to evaluate FGD gypsum’s viability, a study was conducted to determine its influence on live performance (body weight, feed consumption, feed efficiency, and footpad dermatitis), litter characteristics (caking, moisture percentage, and surface temperature) and ammonia volatilization in 3 successive flocks. FGD gypsum was compared with pine shaving (PS), pine bark (PB), PS + FGD gypsum (second material was top dressed over first), PB + FGD gypsum, PS + PB, FGD gypsum + PS, and FGD gypsum + PB. Bedding had no significant influence on feed consumption (FC), feed efficiency (FE), and mortality (M). Body weight and adjusted feed efficiency (AFE) were significantly lower with FGD gypsum compared to that of PS for flock 1, with no differences being observed among the other bedding materials. No differences were noted in live performance for flocks 2 or 3. Incidences of footpad lesions were lower with FGD gypsum than the other bedding materials, but only for flock 1. Bedding treatment had no influence on litter surface temperature. Gravimetric moisture content of gypsum treatments was lower than that of non-gypsum treatments; however, visually, the FGD gypsum was more compacted and had a surface crust. Reductions in ammonia volatilization also were observed during the initial flock with FGD gypsum; however, its effectiveness had diminished by flock 2 and 3.

Summary Current regulatory guidelines to control poultry-borne pathogens, more specifically Campylobacter jejuni, necessitate the need for novel applications of antimicrobials during poultry processing. The objective of this study was to evaluate and compare the efficacy of peracetic acid (PAA; 100 and 200 ppm) and sodium hypochlorite (SH; 25 and 50 ppm) as antimicrobial interventions to reduce C. jejuni on fresh poultry using 2 separate application methods (spray and immersion). Broiler carcasses were inoculated with 10 mL of C. jejuni (ca. 7 log10 CFU/mL) and allowed 30 min for bacterial attachment, followed by either a 60-s immersion or 62-s (460 mL) spray treatment with PAA and SH. Following treatment, the carcasses were rinsed and the rinsate was plated (0.25 mL) onto Campylobacter Cefex agar and incubated microaerobically at 42°C for 48 h. Immersion application significantly (P ≤ 0.05) reduced C. jejuni as compared to the spray application. Results also suggested that PAA as an immersion application showed the lowest survival populations (P ≤ 0.05) of C. jejuni irrespective of the application method.

SUMMARY The effects of 4 levels of supplemental dietary biotin (0.05, 0.1, 0.2, 0.4 mg/kg) on live performance, and the incidence and severity of footpad dermatitis (FPD) were investigated in 2 experiments. In experiment 1, 600 one-day-old female broiler chicks were randomly distributed among 40 pens. Ten replicate pens were allotted to each of the 4 treatments, with 15 broilers per pen. In experiment 2, 1,440 one-day-old mixed-sex chicks were placed in 32 pens (45 chicks per pen), with 8 replications per treatment. Pen BW and feed consumption were measured at 21, 42, and 56 d of age in experiment 1 and at 15, 29, 43, and 57 d of age in experiment 2. Mortality was recorded twice daily and weighed to calculate the adjusted FCR in both experiments. In addition to live performance, FPD incidence and severity were evaluated at each of these time periods using a 3-point scale to document the progression of severity of lesions over time. Litter samples were also collected, pooled, and analyzed for moisture on d 1 and 57 in experiment 2. The live performance of broilers did not vary in experiment 2. Moreover, neither incidence nor severity of FPD was affected by dietary biotin supplementation. Litter moisture did not vary in experiment 2, but equaled or exceeded 35% in all treatments by d 57. No dietary biotin supplementation level resulted in the alleviation of FPD. It was concluded, based on these results, that dietary biotin supplementation is not an effective tool in preventing the development of FPD in broiler chickens.

SUMMARY An experiment was conducted to investigate the effects of graded levels of dietary Na (0.15, 0.20, 0.25, and 0.30% Na) on the live performance and development of footpad dermatitis (FPD) in broiler chickens reared to 49 d of age. On the day of hatch, 1,280 mixed-sex chicks were randomly allotted to 4 treatments, with 8 replicate pens of 40 broilers per pen. Feed and water consumption were monitored and litter samples were analyzed for moisture. The incidence and severity of FPD were assessed by examining all birds on d 28 and 49. Dietary supplementation of broiler diets with graded levels of Na improved (P < 0.05) FCR on d 14 (linear and quadratic), BW on d 28 and 49 (linear), decreased mortality on d 49 (linear), and increased total water consumption (linear). Litter moisture level also increased (P < 0.001) linearly from 24% (0.15% Na) to 32% (0.30% Na) on d 49. Moreover, the incidence and severity of FPD on d 28 and 49 were increased linearly with Na levels in the diet. On d 49, FPD severity was the most severe for broilers receiving the highest dietary levels of Na. With these results, we confirm earlier reports that high dietary Na can increase litter moisture and can therefore be a direct trigger of FPD development in broiler chickens.

SUMMARY A reproducible method for inducing deep pectoral myopathy (DPM) in broilers was investigated. To induce DPM, broilers were subjected to encouraged wing flapping (EWF) by repeatedly raising and lowering them a distance of 1 m. Each cycle resulted in 1 bout of 4 to 6 flaps. At 45 d of age, no DPM occurred in control birds subjected to 0 cycles of EWF or those subjected to 5 cycles, whereas the prevalence of DPM (% of pectoralis minor muscles with lesions) was 7 and 33% in those subjected to 10 and 20 cycles of EWF, respectively. The prevalence of DPM in broilers subjected to 25 cycles of EWF at 49 d of age was 56% and was unaffected by sex or a 0.4-kg difference in BW. The involvement of DPM (i.e., % of muscle surface discolored) and the discoloration score (predominant color of lesions) were also unaffected by sex or BW. The prevalence of DPM at 48 or 120 h after EWF averaged 48% and was unaffected by time from EWF. However, involvement of DPM and discoloration increased with time from EWF, reflecting a change in lesion extent or visibility, and color. Susceptibility to EWF-induced DPM was observed at 26 d of age in males and 36 d of age in females. The prevalence of DPM was greater in males at 33 and 36 d, but was similar thereafter and was unaffected by BW. Therefore, the EWF method of DPM induction is useful for accentuating the occurrence of the disease to facilitate further study and that susceptibility to DPM is primarily associated with age above certain thresholds for each sex.

SUMMARY The physicochemical properties of dietary nonstarch polysaccharides in barley and soybean meals have been correlated with increases in excreta viscosity and adherence, and hence footpad dermatitis (FPD), in broiler chickens. Moreover, high litter moisture has been identified as a possible causative agent of FPD. A total of 448 birds were raised in floor pens in a design involving a 2 × 2 × 2 factorial arrangement of barley (0 or 25% of diet), feed enzyme mixture (supplementation with 0 or 0.1% of Farmazyme BR-M), and litter moisture (with or without added water) and a 3-stage feeding program (8 treatments; 32 replicates; 4 replicate pens per treatment combination, with 14 birds per pen). In addition to measuring live performance, the feet were scored on all birds at 14, 28, and 42 d of age, and the severity of FPD lesions was recorded as none, mild, or severe. A subsample of birds was processed at the end of the experiment to evaluate carcass yields. Pooled litter samples were collected for moisture determination (d 5 and 42) and pH (d 42). The incidence and severity of FPD on d 14 and 28 were due only to litter moisture. No effects on litter moisture or pH were due to barley, although growth performance was adversely affected at 25% dietary inclusion. Carcass yields did not differ between treatments (P > 0.05). Performance of birds was significantly improved by supplementing the feed enzyme mixture, irrespective of the addition of barley or the wetting treatment. Hence, management factors play a significant role in the etiology of FPD in broilers.

SUMMARY a high incidence of footpad dermatitis (FPD) is undesirable in broiler chicken production in terms of both animal welfare and profitability. Bedding type and bedding quality have been identified as possible causative agents of FPD. Four randomized block trials were conducted to determine whether bedding type and transient elevation in moisture influenced the incidence and severity of FPD in broiler chickens. in addition to broiler growth performance and litter moisture, the incidence and severity of FPD was assessed at different ages. the incidence of FPD was significantly increased when the litter moisture was increased by wetting at 14 d of age, but not when the broilers were older than 56 d of age. the severity of FPD was reduced with the improvements in bedding quality. Moreover, particle size of the litter had a direct effect on the occurrence of FPD. Wetting treatment and litter type had little influence on the live performance of broilers in 4 successive trials. From the standpoint of FPD etiology, litter moisture level and particle size may be crucial factors in the development of FPD. Similarly, FPD may be occurring early in the grow-out period, and subsequent improvements in litter quality could reverse the severity of lesions in market-age broilers.

SUMMARY In this study, the influence of complexed Zn (C-Zn) supplementation on live performance (BW, feed conversion, and mortality), skin quality (incidence of sores, scabs, and scratches; footpad dermatitis), processing yields, and meat quality of broiler chickens was assessed at 49 d of age. A total of 1,440 male broilers were assigned to 3 dietary treatments: 1) an inorganic Zn control diet (IC; 80 ppm of ZnSO4), 2) 40 ppm of ZnSO4 in the IC diet replaced with C-Zn (IC-C-Zn), and 3) an additional 40 ppm of C-Zn added on top of the IC diet (IC+C-Zn). Each treatment was provided in a 3-stage feeding program. Body weight and feed conversion were significantly (P 0.05) due to dietary treatments. Inclusion level and source of dietary Zn had a significant influence on broiler live and processing performance in this study.

SUMMARY Bedding availability issues are arising rapidly in the broiler industry that may alter the type and quality of bedding available to growers to rear broiler chickens. Because birds are in direct contact with the litter, the potential impact of bedding materials on footpad health is of concern. In 3 successive trials, 8 different bedding sources (pine shavings, pine bark, chipped pine, mortar sand, ground hardwood pallets, chopped straw, ground door filler, and cotton-gin trash) were compared in side-by-side experimental pens by rearing mixed-sex birds. In addition to broiler growth performance and litter characteristics (moisture, caking, and ammonia volatilization), the incidence and severity of footpad dermatitis (FPD) was assessed at 6 wk of age. Bedding materials had little influence on the live performance of broilers in 3 successive trials. Prevalence of FPD varied significantly (P < 0.05) among the bedding materials. The incidence of FPD paralleled high litter moisture and caking scores, with chipped pine, chopped straw, cotton-gin trash, and pine shavings showing the highest severity scores and mortar sand and ground door filler showing the lowest. From an FPD etiology standpoint, the ability of the bedding to absorb (i.e., ground door filler) and quickly release (i.e., mortar sand) moisture may be the most important characteristics.

SUMMARY Litter is a common source of infectious agents in poultry production environments. Typical sampling methods only examine bacteria on the surface; however, bacteria recovered with these methods may not be representative of the population in the litter. To test this hypothesis, both shallow (top 2 in.) and deep (bottom 2 in.) litter samples were taken and compared with a surface sampling method (i.e., surgical shoe covers). Escherichia coli isolates were recovered from all 3 sample types and examined using an automated ribotyping system to determine the genetic diversity of the isolates. Twenty-six unique E. coli strains were recovered from the 3 different sampling methods. There was no correlation among strains between visit age, house, flock, or farm and ribogroups. Based upon the patterns of E. coli recovery among the different sample types, our results suggest that surface sampling methods are equally capable of recovering common isolates from the litter. Surgical shoe covers were easy to use, provided the same core population of isolates, and were comparable to shallow litter in the number of strains recovered.

The incidence and severity of pododermatitis in broiler chickens is of great concern to the broiler industry, both from product quality and animal welfare standpoints. A total of 1,600 birds were raised in floor pens in a design involving a 2 × 2 × 2 arrangement of protein level [high or low], protein source [all vegetable (VEG) or vegetable plus animal (VEG + ANI)], and sex (male and female) on a 4-stage feeding program (50 birds per pen; 4 pens of males and 4 pens of females per treatment). In addition to live performance, the feet were scored on all birds on 29, 43, and 54 d of age, and the severity of lesions was recorded as none, mild, or severe. A subsample of birds was processed at the end of the experiment to evaluate carcass yields. Pooled litter samples were collected on 29, 43, and 54 d of age for total and NH3-N analysis. Protein level had a significant (P 0.05). Footpad lesions were significantly affected by protein level, protein source, and sex. At 29 d of age, all lesions were mild in severity and varied significantly in incidence by protein source (31% for VEG vs. 41% for VEG + ANI). At 54 d of age, both protein level and protein source significantly increased the incidence and severity of footpad lesions. Incidence of pododermatitis was higher for males (61%) than females (55%). Litter total N was significantly affected by protein level and protein source. The litter NH3-N content, although not significant, except for 29 d of age, showed an increasing trend for each feeding period. The incidence and severity of pododermatitis was significantly affected by protein level, protein source, sex, and age. Hence, nutritional factors play a significant role in the etiology of pododermatitis in broilers.

Broiler house environment, especially volatile NH3 content, has a significant effect on pododermatitis in chickens. The efficacy of NaHSO4 in reducing pododermatitis in broiler chickens was investigated in this study. A total of 960 straight-run 1-d-old chicks were randomly assigned to 16 environmental chambers with 4 different levels of NaHSO4 (4 chambers/treatment). The treatments (TRT) comprised of TRT 1 (control), TRT 2 with NaHSO4 applied at 1 × rate (0.22 kg/m2) on the day of placement of chicks, TRT 3 with NaHSO4 applied at 2 × rate on the day of placement of chicks, and TRT 4 with NaHSO4 applied at 1 × rate on the day of placement of chicks and at 1 × rate on 21 d. Birds were raised to 49 d of age on a 4-stage feeding program with diets formulated to contain high protein levels and all-vegetable ingredients. At 35 d of age, the litter was moistened artificially to see the effect of NaHSO4 on NH3 volatilization. In addition to assessing live performance, feet were scored on 42 and 49 d of age for incidence and severity of pododermatitis. Ammonia concentration (ppm) in the chambers was measured before placement of chicks and on a weekly basis throughout the experiment. No differences in live performance of the birds were observed throughout the study (P > 0.05). Sex had significant effects on incidence of pododermatitis (P 0.05), using NaHSO4 as a litter amendment numerically reduced the incidence of pododermatitis by 10 or more percentage points.

SUMMARY Nutritional and management interventions are needed to reduce the incidence of pododermatitis in poultry. In this study, enzyme (Allzyme Vegpro) supplementation of corn-soybean meal-based broiler diets was evaluated in an effort to reduce total N and NH3 production and its effect on pododermatitis in broiler chickens. A total of 1,600 mixed-sex chicks were raised on floor pens in a design involving 2 × 2 × 2 arrangement of protein level [high or low], protein source [all vegetable (Veg) or vegetable plus animal (Veg + Ani)], and enzyme [with or without enzyme supplementation (0.06%)], on a 4-stage feeding program (4 replicate pens/treatment; 50 birds/pen). In addition to live performance, the feet were scored for incidence of lesions on all birds on 28, 42, and 57 d of age, and the severity was recorded as none, mild, and severe. Pooled gut samples were collected at 57 d of age to determine viscosities of fore- and hindgut contents. Pooled litter samples were analyzed for moisture, total N, and NH3 production at 14, 28, 42, and 57 d of age. Live performance of birds did not vary among the treatments (P > 0.05). The incidence of pododermatitis was significantly affected by protein source at 42 d (P < 0.05), with birds fed all-vegetable diets showing higher incidence and severity than those fed vegetable plus animal diets. At 57 d of age, birds reared on all-vegetable diets with enzyme supplementation showed a lower incidence of mild footpad lesions compared with other treatments. Enzyme supplementation reduced viscosity of the gut contents irrespective of the protein level or protein source. Higher levels of litter NH3 were observed with high-protein diets (28 and 42 d), all-vegetable diets (28 d), and with enzyme supplementation (28 and 42 d). In this study, enzyme supplementation had little effect on litter total N and NH3 production levels, but reduced viscosity of the gut contents and severity of pododermatitis in older birds.

SUMMARY Placing 1-d-old chicks on used litter may lead to unexpected health problems due to high bacteriological counts. Composting litter between flocks is one possible method of decreasing bacteriological counts. At the end of two 7-wk broiler growouts, in-house composting of pine shaving litter was performed, and bacterial counts were taken. In the first trial, composted pine shavings attained an internal temperature of 55°C that lasted for 40 h. After the initial temperature gain,thecompostedlittermaintainedasteadytemperatureof35°C.Aerobicandanaerobicbacterial counts were lower in composted vs. uncomposted litter. Moisture content was lower in the uncomposted pile than the compost pile. Water activity was higher in the composted pile than in the uncomposted litter. Among the 8 treatments in the second trial, litter that was composted, wetted, and covered achieved the highest internal temperatures of >50°C, which was sustained until trial termination (7 d). The other treatments did not achieve a temperature increase of this magnitude and, if not wetted, the observed temperature increase lasted

SUMMARY The effect of age and sex on live performance, processing yields, and footpad quality of broiler chickens was evaluated by rearing 2 commercial strain-crosses (SC) to 56 d of age on 2 diets varying in nutrient density. Each strain cross was placed in 10 replicate pens of 50 birds (25 males and 25 females per pen). Equally distributed among the replicate pens were high- and low-density starter (0 to 21 d) and grower (22 to 42 d) diets with a common finisher fed from 43 to 56 d to all birds. Body weights, adjusted feed conversion, and mortality were determined at 21, 42, and 56 d of age. Processing yields, foot weights, and yields, and the incidence and severity of footpad dermatitis were evaluated on d 35, 42, 49, and 56. No differences (P > 0.05) were seen in mortality between the SC and diet density treatments throughout the course of the study. Strain-cross had a significant effect on body weights at d 21 and feed conversion at d 42, but no differences remained at d 56. Significant SC effects were present for carcass without giblets at d 35, 42, and 56. Diet density effects were limited to carcass withoutgibletsatd35andabdominalfatcontentatd56.Asexpected,femaleshadhigherabdominal fat yields than males at all ages examined. Foot weight and yields were significantly affected (P < 0.05) by SC and sex at d 42, 49, and 56. As expected, foot weights increased with age. The proportion of birds with footpad dermatitis tendedtoincreaseuntil49dofageafterwhichtheystartedtodecline.Malebroilershadsignificantly higher incidence of footpad dermatitis than female broilers at d 49 and 56. Footpad dermatitis response to diet density and pigmentation of the feet was dependent on SC.

SUMMARY Reducing the contamination of poultry houses requires adequate sampling of the environment. Sampling regimens that assess the Salmonella status of broilers prior to processing can be used to identify and process negative flocks first. The current study was designed to evaluate the efficacy of surgical shoe covers vs. drag swabs in the recovery of Salmonella from poultry house litter. Current methods of determining the colonization status of a flock include drag swabs of the litter surface. This method requires significant time and labor in drag swab assembly preparation. The time and cost involved with drag swab assembly, sterilization, and use decreases the likelihood that the number of samples needed to adequately assess the health of a flock will be taken. A simple solution to the sampling problem is the use of surgical shoe covers. Our results indicate that surgical shoe covers are more effective (12.5%) in recovering Salmonella from an infected flock than drag swabs (2.1%). Three Salmonella serotypes were recovered with surgical shoe covers, whereas only one serotype was recovered with drag swabs. The Salmonella serotypes from drag swabs that matched the serotypes from surgical shoe covers were genetically identical. Poultry supervisors often travel to farms to assess a flock prior to processing, and to aid in this evaluation, surgical shoe covers may be worn over disposable plastic boots as supervisors walk through the house. Surgical shoe covers cost $0.70/pair and may be kept in vehicles along with disposable plastic boots.

SUMMARY Bacterial loads associated with sand and pine shavings litter were determined in 2 grow-out experiments with broilers that lasted 7 wk. These experiments consisted of 8 pens each of pine shavings and sand. Birds were placed with 1.16 ft 2 /bird. Litter samples were collected weekly and plated to enumerate (cfu/g) aerobic, anaerobic, and enteric bacterial counts. In addition each sample was analyzed for water activity and percentage moisture levels. Overall, sand litter had lower bacterial counts, water activity, and moisture level compared with pine shavings litter. This work illustrates that, bacteriologically, sand can be a viable litter alternative to pine shavings if locally available.

SUMMARY There has been increasing need for alternative bedding sources for rearing broilers. Sand has been evaluated as a potential bedding source. One problem that might be encountered using sand could be excessive buildup of nutrients, because broilers are typically reared on sand longer than other materials without complete litter removal. High levels of nutrients in poultry litter could create environmental problems when applied to pastures or agronomic crops. This study was designed to quantify the progression of nutrient buildup in sand litter for subsequent flocks. Pooled litter samples were obtained after each flock from broiler houses using sand. The samples were evaluated at the Auburn University Soil Testing Laboratory. Results are reported on a dry-matter basis. Nutrients were measured and minerals were evaluated with a spectrometer. Results showed a significant increase (P < 0.05) in nutrient content in sand houses over time (N 0.74 and 2.26%; P 0.32 and 1.25%; K 0.45 and 1.93%, for flocks 1 and 5, respectively). Nutrient levels in sand litter were similar or lower than those on pine shavings. In general, nutrients in sand increased over time. Sand litter when compared with pine shaving litter had slightly lower nutrient levels on a percentage or parts per million basis after 9 flocks.

Feed restriction programs reduce early growth and decrease mortality in broilers. Observations of subsequent compensatory growth are conflicting and may be influenced by sex and strain. This study examined effects of sex, strain, and early skip-a-day feed removal on broiler performance and meat yield. In experiment 1, males and females were fed ad libitum to 54 d or subjected to 24-h feed removal periods at 8, 10, 12, 14, and 16 d. On d 16, BW was suppressed 44%. Although some compensatory growth occurred and feed conversion was improved, early feed removal adversely affected final BW and meat recovery. Mortality was unaffected by skip-a-day feed removal program. Sex did not affect responses to early feed removal; however, males had greater BW, feed consumption, and weights of all carcass parts. In experiment 2, males from 2 diverse strains were fed ad libitum to 54 d or subjected to 24-h feed removal periods at 9, 11, 13, 15, and 17 d. Body weight was suppressed 44% at the end of feed removal. The reduction of early growth of broilers did not allow for complete recovery of final BW and carcass parts. However, feed conversion was improved by early feed removal. Strain source did not influence responses to early feed removal; the yield strain had superior live performance and meat yield. These data indicate broilers subjected to 5 d of feed removal in a skip-a-day program do not attain equivalent final BW and meat recovery, and although feed conversion was improved, responses were not affected by sex or strain.

SUMMARY Sand is being evaluated in broiler houses as a potential bedding material. A concern regarding sand temperature has arisen as a possible brooding problem. In this study, surface and subsurface temperatures of bedding materials were evaluated for sand and pine shavings (PS) when used as litter in broiler houses. Temperatures were evaluated for new and used sand compared to new and used PS. Sand and PS were placed into 61 × 61 cm (2 × 2 ft) plastic trays 7.62 cm (3 in) deep. Electric brooders wereplaced 38.10 cm (15in) above the beddingsurface and set at45°C. Maximum temperature and time to reach maximumtemperature were measured. Temperature measurements were taken on the surface and 7.62 cm below the surface with an electric temperature/logger. Results showed a significant maximum surface temperature difference (P < 0.05) only when new sandandnewPSwerecompared(38.0vs.43.5°C).Therewerenosignificantdifferencesinmaximum temperature at 3 in below the surface (33.0 vs. 32.7°C) for PS and sand. Time to reach maximum temperature for new PS and sand surfaces were also NS (9.1 vs. 7.6 h), along with the measurements at 7.62 cm below surface (11.6 vs. 9.7 h). No significant differences were found when comparing maximum temperature and time to maximum temperature between used sand and PS at surface or 7.62 cm deep. In conclusion, new sand does not require extra heating time before chick placement in warm weather. Due to a lower maximum temperature (5.5°C less than PS), new sand should be placed during summer months. Used sand with adequate organic matter was numerically, but not significantly, cooler than new or used PS.

Microbiological quality of broiler carcasses, with or without visible ingesta contamination, was compared at pre- and postimmersion chilling sites. A total of 1,080 carcasses was sampled in seven commercial processing plants and analyzed for aerobic bacteria (aerobic plate count; APC), Escherichia coli and Campylobacter spp. counts (log10 cfu/mL), and incidence of Salmonella based on USDA approved microbiological procedures. In all plants, the APC (4.22 vs. 3.27), E. coli (2.36 vs. 1.22) and Campylobacter spp. (1.69 vs. 0.83) counts (log10 cfu/mL), and Salmonella incidence (20.7 vs. 5.7%) were significantly (P 0.05) in microbial counts between carcasses with or without visible contamination at both sampling sites. Overall, immersion chilling resulted in about a 1-log reduction in microbial load on carcasses, compared to prechill levels. These results demonstrate the lack of a direct correlation between the presence of visible ingesta and microbial contamination on poultry carcasses.

SUMMARY Programs that limit early growth of broilers are widely used to reduce mortality and culling and to improve feed conversion. Skip-a-day feed removal is a technique for limiting early growth and has not been extensively examined for broilers. This technique may be more easily implemented than other commonly used programs. Broilers were subjected to one of the following regimens: provided feed ad libitum to 54 d of age (AL); ad libitum except for 24-h removal periods at 8 and 10 d of age (R2); 24-h removal periods at 8, 10, 12, and 14 d of age (R4); or 24-h removal periods at 8, 10, 12, 14, 16, and 18 d of age (R6). Body weights at the end of feed removal were reduced 29, 35, and 41% by R2, R4 and R6 treatments, respectively, when compared with the AL treatment for the same periods. Average daily gains on R4 and R6 treatments were greater upon resumption of feeding ad libitum. Feed removal for a total of 2 or 4 d did not decrease final body weight, feed consumption, or carcass weight; however, removal for a total of 6 d decreased these variables. Cumulative feed conversion, BW, uniformity, mortality, carcass yield, carcass weight, abdominal fat pad, and feed costs per pound of body and carcass weights were not affected by feed removal. These results indicate subjecting broilers to 4 d of feed removal significantly reduced early growth without compromising final weight or meat recovery.

Live performance, carcass quality, and deboning yields of broilers reared on sand as a litter source were investigated in two consecutive trials. Viability of coccidial oocysts in litter was monitored in Trial 1 by placing 320 seeder birds (20/pen) for 10 days prior to the growout. In addition to live performance, chilled carcass grade, foot pad lesions, deboning yields, and gizzard weights were also determined after processing. No differences were found for litter moisture, litter temperature, mortality, or average body weight, between the two litter treatments. Gizzard yields were significantly lower for birds reared on sand than for birds reared on pine shavings. No significant differences were observed in litter coliforms, aerobic plate counts, molds, or oocyst counts between the two treatments. The results obtained in this study confirm earlier findings that sand can be used as a litter material for rearing broilers.

Sand was used as a litter material for broilers in three successive trials, in which 1600 straight-run chicks were reared either on sand or pine shavings as litter source. Body weight (by sex), feed conversion, and mortality were determined at 51 days (Trial 1), 49 days (Trial 2), and 50 days (Trial 3). Chilled carcass grade, foot pad lesions (all trials), and yield (Trial 3) were determined after processing. Litter ammonia production rate (Trial 2) and microbiological quality (Trial 3) were also evaluated. No differences were found for litter moisture, temperature, ammonia production, mortality, feed conversion, or foot pad lesions between the two litter treatments. Broilers reared on sand had significantly greater straight-run (Trial 1) and male body weights (Trials 1 and 2) than birds reared on pine shavings. Abdominal fat yields for birds reared on sand were significantly lower than for birds reared on pine shavings, whereas no significant differences were present in chilled carcass yields (Trial 3). Coliforms (including E. coli) and aerobic plate counts were significantly lower for sand than for pine shavings. Sand has shown good potential as an alternative litter material for rearing broilers.

Poultry processors are concerned that small changes made in the procedures used to grow broilers will affect the quality of the meat, such as the texture. This survey attempted to determine how much the texture was affected by small changes in the diet fed to the bird, the strain of the bird, the age of the bird when it is processed, and the gender of the bird. The cooked fillets were tested for texture using two different devices. No effects on texture were detected due to the diets, strains, or gender used in this study. All meat samples regardless of age, gender, diet, strain, or texture-assessing device would be considered tender. This data indicates that minor changes in diet, strain, and age that could happen in industry would have minimal effects on the ultimate meat quality of the fillets.

Length of preslaughter feed withdrawal has been linked to contamination problems in broiler processing plants. Also, excessive feed withdrawal times are often subjectively associated with increased intestinal fragility during automated evisceration. In addition to intestinal breakage, bile contamination also increases in flocks subjected to long feed withdrawal periods. In this study, tensile strength of the intestines increased with age, with male broilers exhibiting greater hindgut strength than females. On the other had, tensile strength of the intestines decreased and gall bladder size increased significantly as the length of feed withdrawal extended beyond 14 hr. Feed withdrawal programs must be designed to maintain the integrity of the digestive system in addition to targeting physical emptying.

Removing the large breast muscle from broiler carcasses prior to the resolution of rigor mortis results in tough cooked meat. However, the practice of holding carcasses or front halves 8 to 24 hr after chilling prior to deboning to ensure tenderness in the cooked meat is costly with regard to refrigerated space, equipment, and labor. This study determined the effect of extending the chilling time (1, 2, or 3 hr) and subjecting the deboned breast muscles to belt flattening on subsequent physical dimensions (length and width), yield, and tenderness of the cooked meat. Maximum length, width, and weight of each muscle were recorded before and after flattening, and cooked yield and objective texture (tenderness) were evaluated to determine if a combination of the two treatments would eliminate the need to age carcasses for prolonged times prior to deboning. For objective texture, increasing the chilling time resulted in less force necessary to shear the cooked meat, and flattened breasts required less force to shear than did the unflattened breasts. Belt flattening resulted in a loss in weight and an increase in surface area (length and width) of the raw muscle. The combination of carcass chilling for 2 hr followed by belt flattening resulted in cooked meat that would be considered “very tender.”

Male and female broilers were housed during warm weather at varying placement densities to determine the influence of density on carcass grade and yield. Males were reared to 49 days of age at densities of 0.8, 0.9, or 1.0 ft. 2/bird; females were raised at densities of 0.65, 0.75, or 0.91 ft. 2/bird to 42 days. All birds (ten replicate pens/treatment) were graded for carcass defects after processing, while ten birds/pen were held for cone deboning. Live performance of males was influenced by increasing placement density with negative influences on 49-day body weight and feed conversion. Females showed a similar non-significant trend in body weight. The percentage of grade “A” carcasses was reduced at the highest density in females, but due to the offsetting effect of back bruises, this result was not repeated in males. Breast fillet yield was reduced at the highest density in male birds, while this and other yield parameters were not influenced in females. The results of this study confirm that placement density can impact carcass quality, yield, and live performance.

This study collected and retained fifty-eight matching feed samples from spiking mortality and non-spiking flocks for mod and mycotoxins evaluation. Either ELISA or HPLC technology identified and quantified aflatoxin, T-2, fumonisin, and zearalenone in the samples. Twenty samples were further examined using HPLC for a wide range of fusariotoxins and derivatives. Researchers found Aspergillus flavus and Fusarium moniliforme in low incidence. The most prevalent mold identified was Penicillium chrysogenum; however, no differences were noted between spiking mortality or non-spiking farms. No aflatoxins were found in any of the feed samples tested. Fumonisins and deoxynivalenol occurred at low levels but could not be related to spiking mortality. Two unknown HPLC peaks were identified correlating to farms exhibiting spiking mortality.

This study considered the effect of dietary sodium zeolite A (SZA) on processing yields and tibia characteristics of male and female broilers divergently selected over three generations for high and low incidence of tibial dyschondroplasia (TD). Genetic lines included high and low incidence of TD and an unselected control line. Birds (ten replicate pens/line; thirty-five birds/pen) were fed either a standard diet or SZA-supplemented diet at levels of 0.25% and 0.50% from 1-21, 22-50, and 51-56 days of age, respectively. After the study, the high TD line had significantly (P .05) among the lines. The SZA effect was significant (P

The loss in body weight with the transportation of broilers from live production to slaughter has always influence final product yield and quality. This study explored the extent of that influence. Both sexes of two diverse broiler strain-crosses, reared on common feed to 39 and 53 days of age, had feed withdrawn from each group for four hours followed by cooping. Birds were then either held stationary or transported for six hours with a four-hour preslaughter rest. After “on-line” processing, carcasses were cone deboned at either four or twenty-four hours post-chill. This study found that birds lost more weight when transported than if kept stationary. This live weight differential was maintained through post-chill with the whole carcass and all cuts from deboning. Moisture uptake with chilling and subsequent losses from weepage and cutting were unaffected by livehaul. Carcass bruising was more extensive when birds had been kept stationary than if transported. Responses to livehaul were similar for each strain, with both sexes, and at both light and heavy weights.

Male and female broilers from slow- and fast-feathering strain-crosses were grown to 56 days of age to assess skin strength using a punch technique. Broilers were grown under standard management procedures and were provided starter, grower, finisher, and withdrawal diets from 1-21, 22-35, 36-49, and 50-56 days of age, respectively. Skin strength measurements were made weekly on dry, hand-picked skin from the pelvic back region. In addition to live performance, significant differences in skin strength were observed. Skin puncture strength was higher for males than females, and increased linearly with age for both sexes. Skin from slow-feathering strain-crosses appeared to be less elastic than those from fast-feathering strain-crosses. Maturational differences in skin strength due to feathering rate, sex, and age may partially explain skin-related downgrading problems in the processing plant.

Current USDA reprocessing procedures were evaluated in five commercial broiler processing facilities. Reprocessing procedures included a carcass wash/rinse in 20 ppm chlorine at a USDA approved reprocessing station. Results suggest that in most plants current reprocessing procedures are microbiologically justified; however, there does appear to be some plant variation regarding the effectiveness of these procedures. In four of five plants total plate counts, Coliform levels, and E. coli counts were significantly lower on the reprocessed prechill carcasses compared to inspection-passed carcasses. There was no difference in incidence of Salmonella spp. (P=0.18) or Campylobacter jejuni/coli (P=0.57) between the two groups of carcasses. However, in two of the five plants reprocessed carcasses had higher levels of Salmonella spp. than did inspection-passed carcasses. Levels of C. jejuni/coli were either not affected or were significantly lower on the reprocessed carcasses.

Electrical stunning continues to be the method of choice for immobilizing broilers prior to slaughter. Recent research as well as personal observations in commercial broiler processing plants indicate a rather broad spectrum of ideas, concepts and approaches to stunning broilers with electrical currents. Basic concepts of electricity, electrical circuits and the physiology of electrical stunning are reviewed in parallel with current research data. Maintenance of humane slaughter conditions and carcass quality attributes of broilers require integration and application of this knowledge in modern-day processing plants.