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The influence of three dietary metabolizable energy (ME) levels and two light regimes on broiler performance was studied in three feeding experiments. Broiler chicks were fed starter diets containing 3086 (23.5% protein), 3197 (24.6% protein), or 3307 (25.1% protein) kcal of ME/kg of ration. An intermittent lighting (IL) program of 15 min light:45 min darkness was compared to a continuous lighting (CL) control. Light treatment had a significant effect on body weight with CL controls weighing 8.2 and 24.0 g heavier than IL birds at 28 and 56 days of age, respectively. However, IL improved feed efficiency over CL by .040 at 28 days and .019 units of feed per unit of weight at 56 days of age. Although the effects of light X diet interactions were nonsignificant, the higher energy rations increased body weight more in CL than in IL. As the dietary energy of the ration increased, feed utilization at 56 days of age improved proportionally more with IL than with CL. Differences in total mortality, disease condemnations, and downgrades were also nonsignificant. Both male and female broilers grown in IL had less abdominal fat than those grown in CL, but differences were significant only between the female groups (P

The influence of broiler age, litter type, and particle size was studied to determine their effects on litter consumption in two battery trials involving 240 broilers each. In Experiment 1, broilers were provided no litter, wood chips, sawdust, wood fibers, processed newspaper, or newspaper fibers ad libitum from 1 to 49 days of age. In Experiment 2, sawdust was provided free choice daily as the only litter source to broilers starting at 1, 7, or 14 days of age until the 21st day. Broilers consumed significantly greater quantities of sawdust and wood fibers than other litter types and sizes. The consumption rate of all materials decreased after 21 days of age. In Experiment 2, consumption of sawdust was highest when provided any time up to 14 days of age. Based on litter intake and the presence of litter in the gizzards, the data revealed significantly greater consumption of sawdust and high concentrations of sawdust in the gizzard; broilers provided wood fibers also had high intakes but low levels in the gizzard; consumption of wood chips was low but the particles were present in the gizzard; and consumption of newspaper based litter was low and little foreign material was found in the gizzard.

In three floor pen trials involving a total of 14,400 broilers, three particle sizes of processed newspaper (PN) were compared to sawdust as broiler litter. Litter treatments consisted of: hardwood sawdust (SD) as a control, a large particle processed newspaper (L-PN) ranging from 1.27 to 2.54 cm diameter, a medium size (M-PN) of .64 to 1.27 cm, and a small size (S-PN) with particles less than .64 cm diameter. The M-PN and S-PN were used both as a base layer and as a topping agent over a SD base in Trials 2 and 3. In all trials, broilers reared on the S-PN and M-PN used as a base or as a topping had numerically or statistically improved body weights over SD at 10, 28, and 49 days of age. In addition, the birds reared on SD had significantly higher mortality than all other treatments in Trial 2. Litter treatment had no significant effect on feed efficiency, litter cake, or total disease condemnations. The effect on conformation was not consistent between trials. The incidence of breast blisters was comparable to that of SD when the particle size of PN was reduced or when the PN was used as a topping. Broilers reared on PN had improved feathering, but the intensity of yellow color of the skin was reduced more than for broilers reared on SD.

Litter-Aid, a product consisting primarily of ferrous sulfate but also containing propionic acid and magnesium and copper sulfate was incorporated into litter at three application rates (0, .73, and 1.46 kg/m2) to determine its effects on broiler chicken performance and various aspects of litter quality. In Trial 1, litter treatments were applied to litter used for two previous flocks with a 10-week layout period. In Trial 1, there were 10 replicate pens of 175 birds per treatment. In Trial 2, litter used in Trial 1 was retreated, after a 26-week layout period, at the same application rates as Trial 1 with five replicate pens of 175 birds per treatment. This product in Trial 1 at .73 kg/m2 and in Trial 2 at 1.46 kg/m2 significantly (P less than .05) increased body weight without affecting feed conversion or mortality. The product did not significantly (P less than .05) affect litter moisture or litter nitrogen levels, but significantly (P less than .05) decreased litter pH. However, even at the application rate of 1.46 kg/m2, litter pH values rose above 8 as the birds reached 7 weeks of age. This product had no effect on bacteria counts and significantly (P less than .05) increased mold counts. These data indicate that Litter-Aid can be used without detrimental effects on broiler performance or litter quality.

The suitability of three types of recycled paper products for use as broiler litter was studied in three trials using a total of 9,600 broilers. Litter, consisting of hardwood sawdust (SD) as a control, shredded newspaper (SN), processed newspaper (PN), or processed cardboard (PC), was placed in each of four replicate pens in the first trial and reused in subsequent trials. Body weights at 28 and 49 days were significantly influenced by treatment with broilers reared on SN weighing more than SD controls. Broilers on PC were the lightest. Statistically, the PN broilers were heavier than SD broilers at 28 days but similar to controls by market age. Feed conversion was improved with SN at 28 days but did not differ by 49 days. Mortality was not significantly affected by litter material. The moisture content of paper litters was numerically higher than that of the SD control with significantly greater litter caking occurring in the paper litters. However, only broilers on PC had a greater incidence of breast blisters. Overall and total disease condemnation were not influenced by litter material. Skin color scores were improved with the PN treatment.

The effect of floor types on the incidence of feather follicle infection and breast blisters in caged broilers was investigated in two trials. Broilers were reared on corn-soybean meal diets with warm-room brooding. Floor types included litter (control), wire, wire covered with various types of plastic mats, and wire woven with surgical tubing. In trial 1, the effect of a coccidiostat (monensin, 120 mg/kg of feed) was investigated for broilers not on litter, and in trial 2, the effect of supplemental zinc was investigated. Broilers were processed in the laboratory processing plant when they were 51 (trial 1) and 53 days old (trial 2). Carcasses were evaluated for the occurrence of fleshing downgrades, crooked keels, feather follicle infection, and breast blisters. Incidence of feather follicle infection was low for broilers on litter or wire floor and high for broilers reared on plastic mats. Breast blister incidence was low for broilers on litter and plastic mats and was high for broilers on the wire floor. Overall carcass quality for litter (control) was superior to any of the cage treatments. Neither the coccidiostat nor supplemental zinc affected the incidence of breast blisters or feather follicle infection.

A total of 21,000 broilers was used in four experiments (one experiment per season) to evaluate the grow-out performance and carcass quality of five commercially available broiler crosses. The crosses were Hubbard × Hubbard, Hubbard × H&N, Hubbard × Shaver, Ross × Hubbard and Ross × Arbor Acre. Each experiment consisted of three replicate pens (175 birds/pen) per sex per cross. Egg weight differences for the combined experiments were nonsignificant. However, a summary of the four experiments revealed significant broiler cross differences in both day-old male and female chick weights. Both Hubbard × Shaver and Ross × Arbor Acre crosses had lower percentages of saleable chicks. At 28 days of age, male progeny differed statistically in both body weight and feed conversion. At 56 days, Hubbard × Hubbard and Ross × Hubbard females were significantly heavier than other crosses. Numerically, the combined sexes weighed 2063, 2053, 2019, 2013, and 2003 g for Hubbard × Hubbard, Ross × Hubbard, Hubbard × Shaver, Hubbard × H&N, and Ross × Arbor Acre, respectively. Male and combined sex feed utilization differed statistically at this age. No significant broiler cross differences were found in 28 or 56 day mortality or disease condemnations. Carcass quality, as determined by causes of downgrading, revealed Ross sired male progeny had fewer downgrades due to conformation, breast blisters and breast bruises than did Hubbard paternal crosses. In females, statistical paternal cross differences were found only in conformation downgrades. No significant differences were recorded in fleshing, leg bruises and broken or dislocated bones downgrades.

A completely random design consisting of three replicates of 25 broiler chickens (Hubbard x Hubbard) at each of four treatments was used to evaluate the effects of low level, chronic aflatoxicosis on performance and various processing parameters. The treatments in Trial 1 were control, .075, .225, and .675 and in Trial 2 control, .3, .9, and 2.7 micrograms/g toxin in feed (ppm). The chickens were maintained on these treatments from day-old to 7 weeks of age with feed and water available ad libitum. All aflatoxin dose levels in Trial 1 significantly (P less than .05) decreased live, dressed, and chilled eviscerated weight, whereas only 2.7 ppm significantly (P less than .05) decreased live and dressed weight in Trial 2, with chilled eviscerated weight being significantly (P less than .05) decreased at .3 and 2.7 ppm in Trial 2. Parts weights and dimension measurements reflected the aflatoxin-induced decrease in dressed weight. Breast yield (%) was significantly (P less than .05) decreased by aflatoxin while back, wing, drum, and thigh yields were significantly increased by aflatoxin. No effect of aflatoxin was seen on the incidence of crooked keel, feather follicle infection, breast blisters, or conformation. A hypocarotenoidemia and hepatic hyperlipemia were clearly a result of chronic aflatoxicosis in these broiler chickens. These data demonstrate that the toxicity of aflatoxin is dependent on the environment in which broiler chickens are exposed.(ABSTRACT TRUNCATED AT 250 WORDS)

Feeder space requirements were studied in two intermittent lighting (IL) regimes and compared to a continuous lighting (CL) control. Both IL programs were initiated at one week of age. In Experiments 1 and 2 (totaling 12,000 chicks), 1.8, 2.3, and 2.7 cm of circular feeder space per bird were evaluated in a 15 min light: 45 min dark IL (15:45 IL) schedule. In Experiments 3, 4, and 5 (18,000 chicks total), two levels of feeder space (1.8 and 2.3 cm/bird) were studied in a 2 hr light: 4 hr dark IL (2:4IL) program. Compared to CL, IL reared broilers in Experiment 1 weighed significantly less at 27 and 54 days of age while no differences were observed in Experiment 2. Differences in feed conversion at these ages were nonsignificant in Experiment 1 but IL had statistically superior feed efficiency (P In Experiments 3, 4, and 5, broilers in the 2:4 IL program were significantly heavier and had better feed efficiency than CL controls at both 27 and 54 days of age. At 27 days of age, there was a light × feeder space interaction with IL broilers responding better to higher feeder space than CL with respect to feed conversion. Neither light nor feeder space treatment had a significant effect on mortality. The 2:4 IL carcasses had significantly more breast blister downgrades than did CL. In both IL programs, leucosis condemnations were significantly higher than the controls. Airsacculitis and septicemia/toxemia condemnations were slightly less in the IL group than in the CL birds.

Composted municipal garbage (CMG) from two sources was evaluated as broiler litter in three experiments involving a total of 33,920 broilers. An aerobically digested CMG and a windrow processed CMG were each compared to a wood shavings control. Broilers reared on the CMG had statistically or numerically improved body weights compared to the wood shavings control in all trials (31, 12, and 44 g heavier in Experiment 1, 2 and 3, respectively). Feed efficiency was also improved with CMG, whereas litter treatments did not differ in other production or carcass characteristics. Based on limited published reports with wood base litter materials, select trace elements and pesticide levels in CMG litter and tissue were generally within previously reported levels. Exceptions were high mercury, lead, chromium, and nickel in CMG litter, which will require additional research to quantitate significance.

Male broilers (Hubbard X Hubbard) were placed at hatching into a completely randomized 2 X 2 X 2 factorial experimental design with the treatments consisting of 0 and 2.5 micrograms aflatoxin/g of feed (ppm) and 0 and 2.0 ppm ochratoxin A. In Trial 1, there were four replicate pens of 10 broilers per replicate at each treatment level. At 3 weeks of age two replicate pens were randomly selected and placed on control feed (0 to 3 weeks), the remaining two replicate pens were maintained on treatment (full-term). In Trial 2, there were three replicates of 38 broilers per replicate at each treatment level. At 3 weeks of age 13 broilers from each replicate pen were randomly selected and placed in separate housing and fed control diets (0 to 3 weeks). The remaining 25 broilers were kept on mycytoxin treatments until the conclusion of this trial (full-term). Data collected in these trials indicate that body weights of broilers were significantly (P less than .05) decreased by aflatoxin, ochratoxin A, and the combination treatments of the full term feeding regimen. Broilers partially recovered body weight in the 0 to 3-week feeding regimen; however, recovery was less rapid during ochratoxicosis compared to aflatoxicosis. Body weights of broilers in the combination treatment remained significantly (P less than .05) depressed throughout the trials. As body weight decreased, parts weights decreased accordingly. Carcass yield was significantly (P less than .05) decreased by all treatments, primarily by a decrease in breast yield.(ABSTRACT TRUNCATED AT 250 WORDS)