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Broilers grown at three different locations were evaluated with a reflectance colorimeter to determine the effects of robenidine (30 g./ton of feed) and roxarsone (45 g./ton of feed), fed individually and in combination, on shank and skin pigmentation. Sampling consisted of the shanks of birds grown in Missouri and the shanks and skin of birds grown in Georgia and at the Florida Agricultural Experiment Station. Robenidine produced significant increases in pigmentation of broiler shanks and skin (both over and between the ventral feather tracts). Roxarsone alone resulted in a slight increase in shank pigmentation but none in the skin; however, when roxarsone was used in combination with robenidine the birds were better pigmented than those receiving robenidine alone. Females were generally more highly pigmented than the males; this was especially true of the area of the skin over the feather tract.

Two series of experiments were conducted to study the effect of Flavomycin and 3-Nitro-10 on broiler pigmentation in the presence of two different coccidiostats. Monensin was used in all diets in the first series and zoalene in the second series. Flavomycin was included in the feed at 0, 1, 2 and 4 mg./kg. and 3-Nitro-10 was added at levels of 0, 25.0, 37.5, and 50.0 mg./kg. The broilers were grown in the states of Mississippi, Colorado, Arkansas and Florida. Shank pigmentation evaluations were made with a reflectance colorimeter to obtain values for dominant wavelength (DWL), excitation purity (EP) and luminosity. These measurements characterize the shank color in terms of hue, intensity and brightness, respectively. In one series (Monensin) the addition of Flavomycin to the diet resulted in significantly improving shank EP in Exp. 2 and numerically improving it in Exp. 1. No response was obtained in the third and there was a slight decrease in the fourth which may have been due to a significant Flavomycin × 3-Nitro-10 interaction. In the other series (Zoalene) the addition of 3-Nitro-10 resulted in significantly improving shank EP in all four experiments. It did not affect DWL. These responses in shank EP appear to be independent of the response in growth or feed efficiency. The addition of Flavomycin to the diet resulted in significantly, increasing shank EP and DWL in two of four experiments and a numerical increase was obtained in the other two. Again, these responses appeared to be independent of the growth and feed efficiency responses.

JOHNSON and Merritt (1955) suggested that, to be economically sound, selection for improved egg quality should have no adverse effects on the egg producing ability of the strain. The reverse is likewise true; yet these two criteria have received major emphasis in both the breeding and advertising of commerical strains of hens. It has been well confirmed that negative genetic correlations exist between albumen quality and egg production (Goodman and Godfrey, 1955; Johnson and Merritt, 1955; and King et al., 1961). This appears to be verified in the industry as it is accepted that there are strain differences in rate of production and in egg quality. A strain that is lower than average in one criterion tends to be higher than average in the other. A recent important area of research is that of the relationship of initial interior quality to the rate of quality decline during storage. Also important…

Two experiments were conducted to determine the importance of xanthophyll in the diet of growing egg-type pullets. The experiments were designed so that both the rate of xanthophyll depletion from the body and the amount of xanthophyll deposited in the yolk from feed sources could be determined. Pullet chicks were fed diets varying in xanthophyll content during the growing period. Birds fed a diet containing yellow corn and alfalfa were placed on a xanthophyll-free diet at sexual maturity. Birds grown on a xanthophyll-free diet were placed on a layer diet containing yellow corn and alfalfa either at 20 weeks of age or at the time of sexual maturity of the individual bird. Rate of depletion of yolk xanthophyll of birds placed on a xanthophyll-free layer diet at 24 weeks of age was most rapid during the first nine days of the experiment. Birds placed on a diet containing yellow corn and alfalfa at 20 weeks of age, after being grown on a xanthophyll-free diet, produced commercially acceptable eggs at sexual maturity. Those placed on the yellow corn-alfalfa diet at sexual maturity produced yolks essentially equivalent to those of the controls by the time they reached 30 weeks of age.

Hens previously depleted of pigment were fed a white corn basal diet containing 11, 22, 44 and 66 mg./kg. of feed of either beta-apo-8′-carotenal (a yellow pigment) or canthaxanthin (a red pigment). Additional birds were maintained on the basal without added pigments. Seven collections of eggs were made at seven-day intervals beginning after the birds had received the experimental feed for 14 days. All eggs were stored at 13°C. until one week after the last collection at which time all eggs were graded (based on yolk shadow only) by a Federal-State Grader. All eggs were broken out and Haugh units determined. Pooled samples from each group that had been stored for one, three, five and seven weeks were evaluated with a reflectance colorimeter. The dietary level of the pigments had a pronounced effect on downgrading with canthaxanthin resulting in greater downgrading than beta-apo-8′-carotenal. The addition of eight mg. of canthaxanthin per kg. of feed produced as much yolk shadow as 30 to 31 mg. of beta-apo-8′-carotenal. The dietary pigments did not significantly affect Haugh unit values. The hue of the yolk (as measured by dominant wavelength) was directly proportional to downgrading; as dominant wavelength increased from 576.5 nm. (yellow) to 594.5 nm. (reddish-orange), eggs were more severely downgraded.

YOLK mottling first received extensive study shortly after Nicarbazin was placed on the market; among the first studies reporting Nicarbazin mottling were those of Baker et al. (1956) and Polin and Porter (1956). Several reports followed and Nicarbazin is now carefully kept out of layer feeds, but the problems it created have stimulated the interest in yolk defects. However, occasional severe cases of mottling have resulted in considerable economic loss to poultrymen and a corresponding inconvenience and loss to handlers and retailers. Beane et al. (1960) reported a brownish darkening of yolks due to the feeding of piperazine citrate. This report and field cases of yolk mottling in Florida and the Midwest prompted the initiation of the study herein reported. Recently, Beane et al. (1965) reported that three forms of piperazine (citrate, dihydrochloride, and sulfate) caused significantly greater yolk discoloration than that of the controls. This discoloration has been described …

BROILER producers and processors claim that there is a lack of correlation between skin and shank color (Painter, 1969). Work reported by Davies et al. (1969) showed this to be true when pigmentation of skin and shanks was measured using a Hunterlab D-20 color difference meter. Runnels et al. (1966) also found no correlation; however, Culton and Bird (1941), Hammond and Harshaw (1941) and Fry et al. (1969) showed shank color to be highly indicative of skin color. The studies reported herein were conducted to determine whether differential rates existed in the repletion and depletion of pigmentation in the skin and shanks of broilers. MATERIALS AND METHODS (EXPERIMENT 1) Eighteen floor pens were used, each containing five male and five female broiler-type chicks (Peterson × Peterson). Two replicate groups of each treatment were used. The diets (Table 1) were designed to be of low, medium and high xanthophyll content. A…

MANY strains of Bronze and White turkeys are raised and marketed in Kansas and other states but little information is available as to possible differences in edible yield that might be attributable to either strain or variety. Breeders, processors, and consumers are interested in receiving the best value in goods produced or received. Thighs and boneless breasts comprise between 45 and 50 percent of the total ready-to-cook weight of turkeys, Fry et al. (1962). These parts demand the highest price on a per pound basis. Since they are the largest pieces of turkey, they are the parts that are used most often when sliced roasted turkey is served. The purpose of this study was to investigate cooking losses and edible yields of thighs and of boneless breasts of each of 6 commercial strains of Bronze and of White turkeys. EXPERIMENTAL PROCEDURE Thighs and boneless breasts were obtained from 4 toms …

BONE fragility of caged layers often results in bone breakage during processing, causing down-grading of ready-to-cook hens. Many processors with batch-type pickers discriminate against or even refuse to buy caged layers. As the number of cage operations increases, bone fragility will become a more important economic factor to the poultry industry. As the hen lays, she depletes her skeletal system of calcium. Common (1938) showed that up to 24% of the total body calcium of hens laying on a low-calcium diet can be withdrawn from the skeleton for shell formation. Taylor and Moore (1954) reported that there was a reduction in percent shell immediately after pullets were placed on a low-calcium diet; the reduction became progressively greater with each egg laid. They also found that the percent bone ash of pullets dropped when they were placed on a low-calcium diet. Jones et al. (1965) reported that administration of dienestrol diacetate . . .

Two experiments were conducted utilizing 312 egg production-type hens which had been maintained for ten months of lay in individual cages. A depletion diet of 0.11% calcium was fed to cause the hens to go out of production. After production ceased, diets containing graded levels (0.02, 0.06, 0.10, 0.18 and 0.54%) of calcium were fed. It was found that hens fed 0.54% calcium started to come back into production, but that lower levels down to 0.02% did not adversely affect tibia breaking strength or tibia ash. It was concluded that the non-laying hen’s calcium requirement for bone maintenance is 0.02% or less. There was a highly significant correlation between breaking strength and tibia ash, and between body weight and breaking strength.

In two experiments commercial egg-type hens were fed a corn-soy diet to which up to 4.00 percent tannic acid was added. Additional diets used bird-resistant and non-bird-resistant sorghum grains to replace 60 percent of the yellow corn. The sorghum grains comprised 40 percent of the diet and their tannin content ranged from 0.75 percent for the non-bird-resistant variety to 2.44 percent for one of the bird-resistant varieties harvested in the dough stage. Yolk mottling was significantly increased only when the hens were fed tannic acid as 2.00 and 4.00 percent of the diet. These yolks also exhibited a greenish tint. This study shows that bird-resistant sorghum grain can replace 60 percent of the yellow corn of laying hen diets without affecting yolk mottling scores and that a 100 percent substitution of a mature stage bird-resistant variety would not be likely to have any deleterious effect on yolk mottling or discoloration.

BLOOD spots in chicken eggs result in a sizeable economic loss to the poultry industry. In addition, eggs with blood spots which escape detection during candling and enter market channels have a deterrent effect on egg consumption. Although some progress has been made in devising methods for detection of blood spots, the problem of controlling or eliminating these inclusions still exists. Several reports have been published on the factors influencing the incidence of blood spots; heredity, nutritional factors, environment and even management practices have been blamed for high blood spot incidence. From the nutritional standpoint, green feed, alfalfa, vitamin A and vitamin K have been shown to reduce the incidence of blood spots (Nalbandov and Card, 1944, 1947; Carver and Henderson, 1948; Sauter et al., 1952; Bearse, 1955; Bearse et al., 1960, and Berruti and Dedrick, 1961), whereas recent work by Bearse et al. (1962) has shown blood spot incidence…

Three experiments were conducted utilizing 12 strains of egg production-type pullets to determine if tibia breaking strength and tibia ash varied among strains. The data indicate that there was a significant strain difference in tibia strength but that there was no apparent difference in tibia ash among strains. It was found that caged hens had a significantly lower tibia breaking strength when compared to floor hens of the same strain; there were, however, some strains of pullets that were maintained in cages that had a higher breaking strength than other strains maintained on the floor. Floor hens were observed to lay at a slightly higher rate than the caged birds and in the third experiment had higher tibia ash values.

Two experiments were conducted to determine the effects of various levels of potassium chloride (KC1) in the feed on broiler dressing percentages. Feeding KC1 at a level of 0.5% in the diet for two or five days had no significant effect on weight gain, shrink, dry yield, moisture uptake, or overall ready-to-cook (R-T-C) yield. Feeding a level of 0.75% KC1 for two days and 1.00% KC1 for two or five days immediately prior to slaughter increased R-T-C yield significantly; however, there was a trend for these treatments to decrease weight gain during the experimental period.

THE use of synthetic chemicals with estrogenic properties has recently received much attention from both commercial producers and research workers. Numerous reports are in the literature concerning the effect of hormonization on the flavor, tenderness, chemical composition, and body weight of chickens of various ages. This study was made in an effort to determine the effect of hormone treatment, as well as sex and age, on the ash content of chicken bones. Reports from commercial processors, and observations in the University processing plant have indicated that the bones of hormonized birds are more prone to break during handling and processing than are those of non-hormonized birds. It was felt that bone ash percentages might give some clarification of this bone breakage. LITERATURE Holmes, Piggett and Moore (1932) found the percentage ash of chicken bones to be greater in males than in females at three weeks of age. They also found . . .

SummaryAn attachment was designed which made it possible to use the Allo-Kramer shear press to determine the breaking strength of the tibia of 4-week old chicks. Breaking strength determined in this manner was found to be highly correlated with tibia ash. It is suggested that the breaking strength is as good a measure of dietary calcium and phosphorus levels as is tibia ash. Also the breaking strength of bones as determined in this manner may be useful in evaluating factors influencing fragility of bones.