Feather Length Research Articles

Control of contour feather growth of Japanese quail

AbstractGrowth of a contour feather on a dorsal spinal tract of Japanese quail was investigated using a logistic model, in which feather length is determined by two factors, growth rate and growth period. Final feather lengths were constant under most experimental conditions including those under which the growth rate decreased while the growth period increased. Another experimental condition was discovered in which a feather elongated owing to an increase in growth period.Once a feather had fully grown, its length remained constant. After plucking a feather, a new feather grew and its final length was correlated with the old one. Shortening a growing feather by cutting off a distal part did not affect its growth pattern. In addition, shortening a fully grown feather by cutting off the distal part did not activate its follicle. Plucking a feather during growth stopped and erased the present growing phase and initiated feather growth from the beginning to form a complete feather. Repetition of plucking four or five times did not affect the final length of a feather, but did decrease the growth rate, which was complemented by an elongation of the growth period. Feather formation under a short photoperiod condition (8L:16D) resulted in a longer feather which resulted from elongation of the growth period while the growth rate remained constant.

Growth of mallards fed phosphamidon for 13-day periods during three different developmental stages

Mallard ducklings ( Anas platyrhynchos) were exposed to a 13-day dietary treatment of 0, 0·5 or 5·0 ppm phosphamidon at one of three successive age intervals (5–17 days, 18–30 days, or 31–43 days) during a 10-week growth period. Weekly measurements of body weight, wing length, primary feather length, and bill length revealed slower development of primary feathers in those birds treated from 5 to 17 days; treatment effects on body weight and wing length from 6 to 8 weeks of age were observed among those birds treated from 18 to 30 days of age. Some differences in growth patterns among birds treated with the same phosphamidon level, but at different growth stages, were attributed to the varying size of the group with which a duckling was housed at different times in the growth process. No brain cholinesterase depression was observed in any group either 24h after phosphamidon treatment was terminated or at 10 weeks of age.

Age Determination of Mallards

A technique for distinguishing adult from yearling wild mallards (Anas platyrhynchos), from late winter through the nesting season, was developed by applying discriminant analysis procedures to selected wing feather characters of 126 yearlings and 76 adults (2-year-olds) hand-reared from wild eggs during 1974, 1975, and 1977. Average values for feather characters generally increased as the birds advanced from yearlings to adults. Black-white surface area of greater secondary covert 2 was the single most reliable aging character identified during the study. The error rate was lowest in females (3%) when discriminant functions were used with measurements of primary 1 weight and black-white area cf greater secondary covert 2 and in males (9%) when the functions were used with black-white area of greater secondary coverts 1, 2, and 3. Methodology precludes aging of birds in the field during capture operations. J. WILDL. MANAGE. 43(2):384-393 Although the mallard has been studied widely, only limited information has been published on age-related aspects of its life cycle, especially age-related productivity. This paucity of information can be attributed, in part, to the lack of a reliable aging technique applicable during the nesting season. Although keys have been developed on the basis of certain wing feather characters to determine age of mallards during the fall and winter (Carney and Geis 1960, Carney 1964), the reliability of these characters during the breeding season is diminished because of feather replacement and wear before and during the nesting season. The present study was undertaken to develop a technique for reliably separating yearling from older (adult) mallards from late winter to the onset of wing molt in late summer. Several feather measurements were chosen for establishing discriminant functions for each group. Wing feathers were selected on the basis of observed patterns of variation in feather characters, with knowledge of age-related feather variation based on published 1 Present address: Division of Wildlife Research, U.S. Fish and Wildlife Service, Washington, DC 20240. literature, and on the basis of pattern and timing of molt. Variation in primary feather lengths of yearlings and adults was recognized in blue-winged teal, Anas discors (Dane 1968), and redhead, Aythya americana (Dane and Johnson 1975). Wing covert markings were used to age yearlings of certain species, including gadwall, Anas strepera (Oring 1968); common merganser, Mergus merganser (Anderson and Timken 1971); redhead (Smart 1962, Dane and Johnson 1975); and blue-winged teal (Dane 1968). We thank C. W. Shaiffer, who made most of the measurements; B. A. Hanson for assistance in data collection; T. J. Dwyer for his encouragement and help during development of the study; D. C. McGlauchlin, Manager, Audubon National Wildlife Refuge, for support in obtaining mallard eggs for aging studies; F. B. Lee for supervising the rearing of known-age mallards; and R. J. Greenwood for critically reviewing the manuscript.

Growth of nestling sparrowhawks (Accipiter nisus)

Growth rates, mortality and parental care of nestling sparrowhawks were studied in southwest Scotland. Ae Forest was a conifer plantation 200–400 metres above sea‐level, while the Annan valley consisted of farmland, woods, and small plantations on low ground.Nestling sparrowhawks were measured daily from hatching for 21–24 days. Weight, tarsus length and outermost primary feather length were recorded. Nestlings could be sexed by the age of 16 days from the larger size of females, which were significantly heavier than males at one day, had longer tarsi at nine days, and longer primaries at 18 days. Growth rates were calculated using linear regression over standardized periods of about 10 days.Growth rates were independent of brood size, and were negatively correlated with hatching date in one area. Hatching order and growth rate were correlated within broods. The greatest differences in growth rates were found between zones of Ae Forest, and between forest and valley.Twenty‐one per cent of nestlings over two days old died. Causes of mortality were starvation, wet weather, predation and desertion. Most of the mortality occurred in parts of Ae Forest remote from valley woodlands.The presence or absence of the adult female was noted on nest visits. When habitually brooding, until the young were 11 days old, the hen was present on about 85% of visits. By fledging this figure fell to 66% in the valley, and to 32% in the forest.The development of sexual dimorphism is discussed; females gained weight and body size faster than males, which developed various skills sooner.It is suggested that differences in growth rates between parts of the study area were related to food supply. Poor growth rates, high mortality, and lack of parental care all occurred in areas which were remote from sources of abundant prey, as measured by song‐bird censuses.

Growth of the Swainson's Hawk

individuals of .many bird species, and for North American species of Buteo he could discuss only the Red-tailed Hawk (B. jamaicensis). Ricklefs' (1968, 1973) emphasis on the importance of growth rates in avian reproductive biology illustrates the need for continued fieldwork on bird growth and prompts me to report the growth of a brood of Swainson's Hawks (B. swainsoni). No published data describe the growth of wild-raised Swainson's Hawks, although Olendorff (1971) studied captive juveniles and tabulated all references of growth studies of raptors then available. In 1970 I studied the nesting of a pair of Swainson's Hawks 6.4 km east of Arnett, Ellis County, Oklahoma. The nest was a mass of sticks typical for this species, about six dm in diameter and four m up in a 6-m osage orange tree (Maclura pomifera) on the south side of a shelterbelt woodlot. A colony (six nesting attempts) of Mississippi Kites (Ictinia misisippiensis) used the same group of trees. When found, the hawk nest held two nestlings and one egg that did not hatch and eventually disappeared. The ages of the two nestlings were estimated at three and five days on the basis of my experience and comparison with Olendorff's (1971: 234, 243) data for weight and tarsal length. Weight and several body dimensions of the nestlings were measured at irregular intervals (table 1). Tarsal length was measured as the distance along the posterior surface of the tarsus from the base of the first digit to the posterior side of the distal head of the tibiotarsus at the heel; the tarsometatarsus was held perpendicular to the tibiotarsus. I measured the culmen as the chord from the anterior dorsal edge of the cere to the tip. The third-toe claw measurement was the chord from the tip of the claw to the proximal-most ventral surface of the claw at the toe pad. The greatest weights of the juveniles were estimates because the tares for a triple-beam balance were not available, and a spring scale graduated in English units was used to weigh the nestlings. Feather length was the distance from the point where the shaft exited the skin to the tip of the rachis minus natal down. The seventh primary remex and the longer of the two central rectrices were used. The younger nestling was recently dead in the nest when it would have been 32 days old. Its condition did not indicate malnutrition; rather, it died of injuries suggesting either intentional or unintentional

Protection Against Zinc Deficiency by Prior Excess Dietary Zinc in Young Japanese Quail

Three experiments were designed to determine whether an excess of zinc during the first week of life would afford any protection to young Japanese quail during a subsequent period of zinc deprivation. Day-old birds of both sexes were fed an adequate purified diet containing soybean protein with requirement (25-30 mg/kg of diet) or higher levels of zinc for 1 week. The zinc level was reduced during the second week to the deficient level of 1mg/kg of diet, except for the controls which continued to receive an adequate or higher level of zinc (25, 30 or 75 mg/kg of diet). With this low zinc intake, birds that received an initial level of zinc in excess of requirement grew significantly better (body weight and length of primary wing feathers) than those that initially received the required amount of zinc. Data on zinc content of liver, breast muscle, tibia and whole body retention suggest that bone may store zinc consumed in excess of requirement and that this zinc may be available for utilization during a subsequent period of zinc deprivation in a growing animal that has rapidly remodeling bones.

Age Determination of Female Redhead Ducks

Eighty-seven fall-collected wings from female redhead ducks (Aythya americana) were assigned to the adult or juvenile group based on and tertial shape and wear. To obtain spring age-related characters from these fall-collected groupings, we considered parameters of flight feathers retained until after the first breeding season. Parameters measured included: markings on and width of greater secondary coverts, and length, weight, and diameter of primary feathers. The best age categorization was obtained with discriminant analysis based on a combination of the most accurately measured parameters. This analysis, applied to 81 wings with complete measurements, resulted in only 1 being incorrectly aged and 3 placed in a questionable category. Discriminant functions used with covert markings and the three 5th primary parameters were applied to 30 known-age juvenile, handreared redhead females; 28 were correctly aged, none was incorrectly aged, and only 2 were placed in the questionable category. J. WILDL. MANAGE. 39(2):256-263 To estimate the production of a given waterfowl breeding population, information is needed on the expected productivity of various age cohorts. Of particular importance is the productivity of yearling birds compared with that of older females. Most of the techniques used to distinguish firstyear birds from adults are not valid for most ducks in the spring, because adult growth and sexual development have been attained and identifying feathers have been replaced. Even with those external characters of waterfowl that are age-related in in the spring (e.g., eye color [Trauger 1974] and bill spots [Kuroda 1937, Dane 1968]), the overlap between adult and first-year birds diminishes the usefulness of these

Quantitative and Qualitative Age and Sex Criteria of the Starling, Sturnus Vulgaris, in March

Age and sex criteria are studied of 74 Starlings, 39 ♂ ♂ (14 first-year) and 35 ♀ ♀ (27 first-year), in March. Weight, bill length, wing length, lengths of the iridescent parts of the throat and breast feathers, lengths of the white tips on the breast and abdomen and the amount of black colour on the bill are treated quantitatively. Qualitatively treated are: gloss of the plumage, gloss on the lesser secondary coverts, gloss on the breast, pointedness of breast and abdominal feathers, length of the throat feathers, gloss on the end of the outer web of the secondaries, colour of the under wing coverts and form of the upper tail coverts. Skull ossification was expected to be completed in March, but finding 7 birds with an incompletely ossified skull, this character has been included in our study.

The Food of Nesting Double-Crested and Pelagic Cormorants at Mandarte Island, British Columbia, with Notes on Feeding Ecology

without ocelli showed faster growth from the fourth to eighth week than plumes with ocelli. Table 4 shows that the size of the after shaft of plumes increased with plume size. Sizes of barbs were not proportional to plume size. Heads of plumes showed no remarkable difference in size with size of plumes, but instead the size decreased beyond a feather length of 50 cm. Brown ocelli are largest (6 cm wide) in smaller-sized plumes, i.e., 50 cm, and they decrease with plume length. Green and blue ocelli are largest (3.5 and 2.5 cm, respectively) in medium-sized (98 cm) plumes, then the sizes decrease with further plume length. Embedment of plumes is directly proportional to plume size.

Snow goose primaries as indicators of age and sex.

Significant differences were found, by age and sex, in mean vane length and mean weight of the fourth primary flight feathers of lesser snow geese (Chen caerulescens) collected in the Mackenzie River delta in September, 1971. Such differences might have research or management applications.

Influence of date of egg production and diet on pheasant chick development

Ring-necked pheasant (Phasianus cokhicus) chicks were hatched at weekly intervals for 14 weeks from eggs laid by hens fed two diets of different protein and energy levels. Chicks from each hatch were subjected to two different nutritional planes by feeding them a control diet yielding 2.91 kcal of metabolizable energy per gram and 23.7% protein, and an experimental diet yielding 1.88 kcal of metabolizable energy per gram and 14.3% protein. Weight of the chicks at hatching, and three indices of growth, increase in body weight, length of the tarsal bone, and length of the seventh primary feather, were taken during the first 3 weeks of life. Weights of day-old chicks and their rates of development were unrelated to the chronology of egg production, the sex of chicks, and the diets fed to the parent hen. Differences between rates of development of the chicks were attributed to differences between the amount of protein and energy metabolized from their diets.

Statistical Analysis of Character Correlations in Brewer's Blackbirds

Power, D. M. (Dept. of Ornithology, Royal Ontario Museum and Dept. of Zoology, University of Toronto, Toronto, Ontario, Canada) 1971. Statistical analysis of character correlations in Brewer's Blackbirds. Syst. Zool., 20:186-203.-Character correlations among 37 skin and skeletal characters within a statistically homogeneous sample of Brewer's blackbirds (Euphagus cyanocephalus) were analyzed by component analysis and average linkage cluster analysis in order to isolate structural and/or functional character sets. Associations were assessed using product-moment correlation coefficients, partial correlations that corrected for a general size factor, and a subset of special partial correlations that corrected for a group factor defining high intercorrelations among limb bone length measurements. With ordinary correlations separate associations were identified for limb bone length, flight feather length, bill length, sternum size, bill width, and limb bone thickness. Some characters were predominantly independent. Partial correlations that corrected for covariation due to the group limb bone length factor indicated special associations among wing bones. An overall size factor is defined as that component which accounts for most of the covariation among all characters. Partial correlations correcting for this factor were analyzed and several size-independent associations emerged. The limb bone length assemblage is in part size-dependent. Size-independent associations include wing bone length, flight feather length, bill length, bill width, and limb bone thickness assemblages, and possibly a partial leg bone length set. Association of three sternal characters appears size-dependent, however a special size-independent association between sternum length and keel height was found. In addition, low-level, size-independent associations are found for pelvis width and bill height characters, as well as between the scapula and coracoid in the pectoral girdle. Results suggest the existence of selective factors that affect the development of functional complex as a whole. Comments are given concerning redundant characters in systematic studies and a temporary solution is offered concerning the problem of adequate sample size in studies of character correlations. [Character correlations; Brewer's blackbirds.] Character correlations within populations are the result of individual ontogenetic processes and natural selection. Perhaps the greatest contributions to the quantitative assessment of character relationships, particularly in terms of size and shape, have been in the study of allometry. Gould (1966), in his review of concepts and methods in t-his field, and in his own work, has shown the contributions that can be made here in understanding ontogeny and phylogeny. In the last several years relatively few papers have dealt in depth with covariation in non-growing systems, but the single underlying generality that can be made seems to be that characters related in structure or function tend to be more highly correlated than are others (e.g., Berg, 1960; Olson and Miller, 1958). As Van Valen (1965) has pointed out, it seems necessary to postulate selection for developmental patterns that affect functional complexes as a whole. For populations of adult, non-domesticated birds, very few attempts have been made to investigate correlations or to isolate structural or functional subsets for more *than just a few morphological characters. Nor have there been attempts to investigate covariation independent of sizeoTr general factors at the population level. The present study is an analysis of correlations among a number of morphological characters from four subsamples (two sexes and two localities, treated separately and in combination) of adult Brewer's blackbirds (Euphagus cyanocephalus; Icteridae), a common species widespread in western and central

Age Determination of Blue-Winged Teal

Primary freater secondary coverts, and the degree of bill spotting were evaluated as characters for use in the spring to distinguish first-year, blue-winged teal (Aras discors) females from older ones. The length of the 10th primary feather did not prove suitable to separate different aged females. Extreme primary lengths might be used to determine the age of some males. In females that have been through a postnuptial molt the greater secondary coverts have a more symmetrical, and more acutely angled, white, inverted V-marking. Any female with a V subjectively classified as good has gone through at least one postnuptial molt, and a female with no sign of a V on the coverts is a juvenile or yearling before her first postnuptial molt. By measuring the longest bill spot on the upper mandible of each known-age female, it was possible to determine the age of some female teal. Because the spots fade during the breeding season, no lower size limit could be set to delineate first-year females at that time of year, but any nest-trapped hen with a spot longer than 10 mm was considered to be older than 1 year. Upper and lower limits were also established to distinguish some yearlings and 2year-olds in the fall. E DETERMINATION OF BLUE-WINGED TEAL1 RLES W. DANE, Purdue University, Lafayette, Indiana2 This evaluation of age characters was prompted by a need to establish a means of distinguishing first-year, blue-winged teal females from older females during the breeding season, so that reproductive in1 This work was financed by the Purdue Research Foundation and the North American Wildlife Foundation, and the field research was conducted at the Delta Waterfowl Research Station, Delta, Manitoba. 2 Present address: Northern Prairie Wildlife Research Center, Jamestown, North Dakota. is evaluation of age characters wa o pted by a need to establish a me ns distinguishing first-year, blue-winged al females from older females during the eeding season, so that rep oductive inhis work was fina ced by the Purdue Research formation from nest-trapped females could be used in a study of the influence of age on reproductive capability. Cloacal characters (Gower 1939, Hochbaum 1942), notched rectrices (Pirnie 1935:275), and markings and condition of tertials (Carney and Geis 1960) are characters used in distinguishing juvenile waterfowl from adults in the fall, but these are not valid for separating first-year ducks from older birds in the breeding season. Tarsi and bills of redheads (Aythya americana) attain full est-trapped females could of the influence of age i e ca ability. Cloacal charThis content downloaded from 40.77.167.35 on Wed, 28 Jun 2017 17:57:48 UTC All use subject to http://about.jstor.org/terms 268 Journal of Wildlife Management, Vol. 32, No. 2, April 1968

A New Method for Sexing Ruffed Grouse in Late Summer

The need for objective criteria to determine the sex of molting ruffed grouse (Bonasa umbel- lus) in late summer (juveniles 13 weeks or older, and adults) led me to measure the length of a single barb of the central tail feather at a point 50 mm from the tip of the tail. In a sample of 1,518 birds whose sex and age were determined by plumage characteristics, I found that sex of individual grouse whose barb measurements fell outside the overlap (middle) size range could be determined by barb length, with an error of about 1-4 percent. Birds with barb length outside the overlap range comprised about two-thirds of the adults and one-half of the juveniles. Methods for determining sex and age of fully grown ruffed grouse by using the plucked length of the central tail feather, the shape of the outer three primaries of the wing, the diameters of primary 9 and the central tail feather, and the sheathing at the base of primaries 8 to 10 have been carefully authenticated in Wisconsin (Hale et al. 1954, Dorney and Holzer 1957). How- ever, molting adult and juvenile grouse in late summer have incompletely grown rec- trices, making it necessary to develop other criteria for determining sex. Palmer (1959) in Michigan noted that the eye patch of juvenile males had vivid to moderate pig- mentation while that of the females was colorless; he relied principally on this dif- ference in eye patch color to determine sex in molting juveniles. Palmer's eye-patch method for determining the sex of molting grouse was not published when I was con- ducting field studies on ruffed grouse in Wisconsin, but because the determination of relative color intensity is subjective, it appears useful to describe a more definitive method at this time.

Stuffing an Emperor Penguin

The author stuffed an Emperor Penguin in May, 1953. He obtained several informations from the salt-pickled penguin which was brought from the Antarctic Sea. So fatty were both the exterior and interior of the skin that the stuffing was difficult.The greater part of the body was about to shed its feathers, and new feathers were growing half the length of the old feathers. Feather sheeth in the subcutaneous part resembled the hairs of mammalian fur, and did not like the feathers of average birds.To my surprise, a roughly one-inch scar was found on the left-thigh, which had already healed. On the new skin were growing feathers. Under the subcutaneous fat, the wounded and broken skin was found buried with its feathers. All over the tongue were rough and strong spines which resembled a twoothbrush. The penguin completely sets its two heels on the ground. Its skeleton was solid. Though dry enamelled wires were used in stuffing, they melted when it touched the fat of the penguin.

Relative potencies of thyroxine and triiodothyronine based on various criteria in thiouracil-treated chickens.

Relative sensitivities of various criteria, which were found to be suitable qualitative indicators of thyroxine and triiodothyronine, were determined by calculating and comparing the amounts of each hormone necessary to maintain the control level of each criterion in thiouracil-treated chicks. Relative sensitivities of the criteria used for determining action of thyroxine were: feather length > rectal temperature > weight of the thyroid > oxygen consumption rate > heart rate > suffocation time; of triiodothyronine: feather length > rectal temperature > suffocation time > thyroid weight > oxygen consumption rate > heart rate. Relative potencies of thyroxine and triiodothyronine were determined by comparing the magnitudes of responses of each of the above criteria to equal or equivalent quantities of these two hormones. Thyroxine and triiodothyronine exhibited equal potency in affecting the above criteria in thiouracil-treated chicks except for a) antigoiterogenic action in which case thyroxine was more potent than triiodothyronine and possibly b) elevation of rectal temperature for which action triiodothyronine appeared to be the more potent hormone.

HYBRIDIZATION OF THE PHEASANT AND FOWL

Pheasant males produced by crossing Mongolian pheasant males with Ringneck pheasant females were mated naturally and by artificial insemination with Dark Cornish and Silver Cornish females. Among 1,409 eggs, 3.48 percent exhibited development when incubated. The hatchability of these “fertile” eggs was 6.12 percent. One female and four male hy brids developed sufficiently to pip the shell. Two chicks died in the shell and both proved to be males. The remaining female and two male hybrids hatched and were raised to ma turity. The incubation period was 26 days. The behavior and general appearance was more pheasant-like than chicken-like. Body weight and tail feather length were intermediate between the parent species. The hybrids had none of the comb, wattle or earlobe char acteristics of the chicken parent. The ear tufts and velvety red feathered areas on the sides of the face of the pheasant sire were also absent. The shank color was slate like that of pheasants, and the spurs were intermediate in shape and location between the parent species. No sexual activity was observed and subsequent dissections showed infantile or degenerate gonads.

The clinical significance of photic stimulation

The visual systems of birds are hypothesized to have higher temporal resolution than those of humans, suggesting that they may be able to perceive the flicker emitted from conventional low-frequency fluorescent lights (LF; 100 Hz in Europe, 120 Hz in the U.S.A.). These lights are commonly used in the housing of captive birds and this may affect both their welfare and performance in experiments. We carried out mate choice experiments on European starlings, Sturnus vulgaris, under both low- and high-frequency fluorescent lights (HF; >30 kHz, at which flicker is imperceptible). Indicators of male condition and size, together with the reflectance spectra and length of the males' throat feathers, were also recorded to ascertain which variables correlated with female preference. Females ranked males consistently under HF, but not LF, lighting, and individual females chose different males under the two lighting types. Under HF lighting, females chose to spend more time with males that had longer throat feathers. The flicker rate of the light clearly affected the choices made by the females, possibly because of nonspecific stress effects or decreased discrimination ability. Our results imply that careful interpretation of mate choice experiments is needed, especially with regard to the lighting types used, to elucidate the real cause behind any variation shown.

Californian Flicker-Quill Headbands in the Light of an Ancient Colorado Cave Specimen

ROM MANTLES CAVE, in Dinosaur National Monument, in the northwestern corner of Colorado, Burgh and Scoggin (1948) report a buckskin pouch which contained a remarkably well preserved flicker-quill headband turned up with miniver. The similarity of this ancient ceremonial headdress, apart from its fur trimming, to the ethnographic flicker-quill headbands of California, raises a challenging culture-historical problem. The evidence suggests that the similarity may rest on cultural connections and that the flickerquill headband may be an important key for the understanding of Californian-Great Basin relationships during the first millennium of this era. Burgh and Scoggin (1948, pp. 38-41) have described the archaeological circumstances of the Colorado find in detail. Mantles cave is one of several non-residential caves in Yampa Canyon, containing small chambers dug into the silt or sand of their floors. The culture represented in the caves and open sites has been identified in part with the Fremont culture of east-central Utah, a basically Basketmaker manifestation extending along the Green River and its tributaries, and dating from about 400 to 800 A.D. (Morss, 1931; Lister, 1951). The Mantles cave headband and other Yampa Canyon specimens are now in the Henderson Museum, University of Colorado, Boulder. The Colorado headband merits a detailed description. Fundamentally, the technique of manufacture is the same as that employed in the making of the California specimens: the central tail feathers of the Red-shafted Flicker, Colaptes cafer collaris, have been trimmed of thei vanes so as to leave the red-orange shaft or quill bare for about 8 cm. of the total feather length of about 12.5 cm. The remaining untrimmed 4.5 cm. of the feather at the distal end forms a roughly diamond-shaped tuft. The trimmed feathers, placed side by side, form a continuous elongated mat of quills. The Mantles cave band is 58.5 cm. long, and contains 370 or more feathers, which would have required some 60 birds. The quills are arranged so that their ventral or undersurface portions face the front of the headdress-i.e., the surface not in contact with the wearer's head. The quills are held together by two horizontal threads of sinew, which pass through perforations which pierce each quill at two points below the diamond-shaped tuft. The uppermost of these threads stops 14 cm. from the right end, and 12 cm. from the left end of the band, in terms of the wearer's right and left. The lower thread runs the whole length of the band. The quills are also anchored by the basal binding strips. Along the front edge of the band this consists of a trimming of ermine, made from the pelts of three weasels (Mustela frenata, probably nevadensis) in winter pelage, averaging 2.25 to 2.50 cm. in width. Along the back edge is a buckskin backing strip, of the same width as the ermine band, which would be in contact with the wearer's forehead. These strips hold the bases of the row of quills between them, and they are firmly united by stout sinew lashings a about 1 cm. intervals, both along the lower edge of the headdress and along the upper laptes cafer collaris, have b en trimmed of ir vanes so as to leave the r d-orange shaft 147 HEWES]

Sparing effects in the biosynthesis of the aromatic amino-acids in Escherichia coli

Stress in animals is a concern in conservation breeding programs and livestock production facilities. The biological stress response is mediated by the release of glucocorticoids, which can suppress reproduction, growth, and immunity if recurrently activated. Feathers can be used to extract and monitor concentrations of corticosterone, a primary glucocorticoid in birds. However, current techniques for extracting feather corticosterone present challenges, including difficulty assessing extraction efficiency or hormone recovery, inconsistent extraction across feather lengths or pieces, and several uncertainties regarding the mechanisms of hormone deposition into feathers. To overcome such challenges and to provide tools useful for facilitating conservation breeding and livestock production, we developed and validated an alternative procedure for extracting feather glucocorticoids. We first developed a protocol to enzymatically digest the protein matrix of feathers using a keratinase, such that non-protein analytes could be isolated by organic extraction. We then developed an extraction protocol and evaluated techniques by measuring extraction efficiency and by testing parallelism and hormone recovery (accuracy) using radioimmunoassay. Our results demonstrated high and consistent extraction efficiency, as well as high accuracy and reliable parallelism to a standard curve upon measurement of corticosterone concentrations from extracts. By dissolving feather material into solution prior to extraction, we were able to replicate hormone deposition into the feather matrix and ensure consistent extraction across feathers. This work provides additional support for the validity and practicality of extracting glucocorticoids from feathers. Our extraction protocol is likely to extend to other applications as well, including the isolation of numerous non-protein analytes from various keratinized tissues.