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Four groups of 70-wk-old broiler breeder females were fed once daily at 0600, 1000, 1400, and 1800 h to determine the effect of feeding time and eating on body temperature. The photoperiod was from 0430 to 1930 h. Four floor pens of 30 hens each were assigned per feeding time. Following a 9-day adjustment period, body temperature was determined, in series, by rectal probe of 5 birds/pen at 7 and 3 h prefeeding and 1, 5, 9, and 13 h postfeeding. Body temperature was increased .5 C at 1 h postfeeding in all groups and at 5 h postfeeding in the 0600-h fed group. The rate of feed consumption was fastest with afternoon feeding. Four 1-yr-old broiler breeder males were implanted with an FM radio transmitter for monitoring body temperature and housed in an environmental control chamber. Body temperature was monitored when the birds were fed at 0600, 1000, 1400, and 1800 h. The chamber temperature cycled from 22.2 to 33.3 C (22.2 C: 2200 to 0800 h; 33.3 C: 1200 to 1600 h; 27.8 C: 0800 to 1200 h and 1600 to 2200 h). Lights were on from 0430 to 1930 h. Body temperature changes were also monitored under constant temperature (27.8 C) and light for birds fed ad libitum or at 1000 h. Body temperature increased as much as 1.5 C following feeding and reached a maximum at 5, 4, 3, and 2 h postfeeding at feeding times of 0600, 1000, 1400, and 1800 h, respectively. Males unable to feed displayed a significantly increased body temperature when they observed other birds eating. A specific body temperature response to feeding activity was observed only when males were fed once daily under constant environment.

INTRODUCTION CALCULATIONS of surface area of irregularly or asymmetrically shaped objects may involve complex measuring methods or mathematical computations. In those structures exhibiting symmetry, the procedure may be less complicated; for example, the total surface of a parallelepiped is equal to the summation of the areas of its sides. On the other hand, the surface area of objects has been reckoned using adhesive tape, weights of peelings, or by considering the surface as a function of the two-thirds power of the weight (Mueller and Scott, 1940). The surface area of avian eggs has been estimated in similar ways (Dunn and Schneider, 1923; Murray, 1925; Marshall and Cruickshank, 1938; and Romanoff and Romanoff, 1949), but the most useful and accurate methods have been based on the volume (Romanoff and Romanoff, 1949). However, if the object forms a surface of revolution, like an egg shell, it is possible to perform these measurements utilizing . . .

INTRODUCTION IT IS well known among those who examine egg contents that the blastoderm is found on the upper surface of the yolk—and more-or-less independently of the position of the egg’s major axis with respect to gravity. This characteristic location results from density gradients in the yolk and a general association of the blastoderm and the pole of minimum density. However, in a series of experiments on the effect of mechanical forces on embryo development (Besch, 1964; Besch et al., 1965), it was observed that the pole of minimum density did not coincide with the blastoderm position on the surface of the yolk. The present study was undertaken to determine these positional differences of the yolk and the influence of various factors on them. METHOD The egg used in these experiments were from Single Comb White Leghorns (Gallus domesticus), usually abbreviated S.C.W.L., and from Japanese quail (Coturnix japonica). After …

IT IS perhaps paradoxical that the quality of the non-edible portion of an egg is a primary factor in the production of market eggs. However, the importance of shell strength is indicated by its frequent study. In a recent review of the subject (Tyler, 1961), 16 methods of shell strength determination were reported. Subsequently different methods have been reported by Rehkugler (1962) and Frank et al. (1964). In general, quantitative studies of shell strength have been made by either static loading of eggs, or impacting some moving object against them. None of these methods simulate the more frequent conditions of shell failure—dynamic situations involving impact deceleration of the egg. Dynamic testing of egg shell strength requires large and complex machines—drop testers—which are not ordinarily available to those interested in shell quality. However, impact deceleration can be simulated by increasing the hydrostatic pressure of the egg contents. A…

Adult, male Single Comb White Leghorn chickens (SCWL) were housed unrestrained in individual cages in a controlled environment room with a photoperiod of 12L:12D. By means of surgically implanted radio transmitter, body temperatures were recorded hourly for five consecutive days at each of six experimental temperatures: 23, 26, 29, 32, 35, and 38 C. The data were evaluated statistically by correlogram, periodogram, and harmonic analysis. Period length of each cycle was about 24 hr at all ambient temperatures. No significant differences in deep body temperature were observed until the ambient temperature reached 32 C; but highly significant increases were detected between 32, 35, and 38 C. Diurnal differences in body temperature ranged from .6 to 1.1 C. It has been suggested that the body temperature of male chicken may be under the control of a biological clock that synchronizes with the solar day.

Thirty anesthetized, male White Leghorn chickens, approximately six months old (average body weight, 2.030 ± 0.048 kg.), individually inhaled radioactively labeled (I-128) monodispersed latex particles. Six birds each were exposed to one of five particle sizes (0.091, 0.176, 0.312, 1.1, and 3.7 to 7 microns). During exposure, the respiratory rate and tidal volume were monitored by a whole-body plethysmograph. Inhaled aerosol was detected externally for each of seven, equal-length sections along the axis of the body. Percentages of deposition for each section were calculated from the corrected time-decay activity. Significant differences (P