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The U.S. Congress has passed legislation requiring the U.S. Environmental Protection Agency (U.S. EPA) to develop, validate, and implement screening tests for identifying potential endocrine-disrupting chemicals within 3 years. To aid in the identification of methods suitable for this purpose, the U.S. EPA, the Chemical Manufacturers Association, and the World Wildlife Fund sponsored several workshops, including the present one, which dealt with wildlife species. This workshop was convened with 30 international scientists representing multiple disciplines in March 1997 in Kansas City, Missouri, USA. Participants at the meeting identified methods in terms of their ability to indicate (anti-) estrogenic/androgenic effects, particularly in the context of developmental and reproductive processes. Data derived from structure-activity relationship models and in vitro test systems, although useful in certain contexts, cannot at present replace in vivo tests as the sole basis for screening. A consensus was reached that existing mammalian test methods (e.g., with rats or mice) generally are suitable as screens for assessing potential (anti-) estrogenic/ androgenic effects in mammalian wildlife. However, due to factors such as among-class variation in receptor structure and endocrine function, it is uncertain if these mammalian assays would be of broad utility as screens for other classes of vertebrate wildlife. Existing full and partial life-cycle tests with some avian and fish species could successfully identify chemicals causing endocrine disruption; however, thcse long-term tests are not suitable for routine screening. However, a number of short-term tests with species from these two classes exist that could serve as effective screening tools for chemicals inducing (anti-) estrogenic/androgenic effects. Existing methods suitable for identifying chemicals with these mechanisms of action in reptiles and amphibians are limited, but in the future, tests with species from these classes may prove highly effective as screens. In the case of invertebrate species, too little is known at present about the biological role of estrogens and androgens in reproduction and development to recommend specific assays.

The toxic properties of naturally weathered Exxon Valdez crude oil (WEVC) were assessed in a battery of acute and subchronic toxicity tests using mallards, Anas platyrhynchos, and European ferrets, Mustela putorius. Adult mallard acute oral toxicity study results indicated no mortalities or signs o toxicity, i.e., no-observed-adverse-effect level (NOAEL) and median lethal dose (LD50) > 5,000 mg/kg. Acute oral feeding and food avoidance tests with ducklings also indicated no toxicity (NOAEL and LC50 > 50,000 mg/kg diet) with no evidence of food avoidance (FAC50 > 20,000 mg/kg diet). No mortalities or toxic signs were noted in a 14-d feeding study with adult birds at dietary concentrations up to 100,000 mg WEVC/kg diet. Among clinical and physiological end points evaluated, the only significant difference noted was an increase in liver: body weight ratios in the 100,000-mg WEVC/kg diet dose group. No differences in clinical chemistry or hematological parameters were noted, and there were no consistent differences in histological evaluations of organ tissues. Daily oral doses of up to 5,000 mg/kg of WEVC over 5 d resulted in minimal effects on ferrets. Increased serum albumin concentrations were observed in the 5,000-mg/kg dose group females and decreased spleen weights were noted in femalesmore » of all WEVC treatment groups. No other significant observations were noted.« less

The toxic properties of naturally weathered Exxon Valdez crude oil (WEVC) to avian and mammalian wildlife species were evaluated using the surrogate species, mallard duck, Anas platyrhynchos, and European ferret, Mustela putorius. This study was conducted to evaluate the potential for toxic (rather than physical) injury to wildlife species that may have been exposed to WEVC, either through external contact or through dietary uptake. Previous studies have assessed the toxicity of unweathered crude oils, including Alaska North Slope Crude, but little information exists regarding the toxicity of a naturally weathered crude oil, typical of that encountered following a spill. A battery of laboratory toxicity tests was conducted, in compliance with standard and published test procedures, to evaluate acute and subchronic toxicity of WEVC. These included tests of food avoidance, reproductive effects, and direct eggshell application toxicity. Naturally weathered EVC, recovered postspill from Prince William Sound, was used as the test material. 36 refs., 7 figs., 4 tabs.

Standard 8-day toxicity experiments were conducted with mallards ( Anas platyrhynchos L .) and northern bobwhite ( Colinus virginianus L .) exposed to a range of dietary sodium monofluoroacetate (Compound 1080) concentrations. Food LC50 estimates for mallards and northern bobwhite were 527 and 385 ppm, respectively. Food avoidance tests in which birds were given free choice between equal amounts of clean and contaminated food indicated that mallards and northern bobwhite avoided consumption of 1080-treated food at levels equal to or greater than 236 ppm and 95 ppm, respectively. Although water LC50 estimates for both species were approximately an order of magnitude less than those estimated from the food LC50 experiments, these differences could largely be attributed to the fact than, on a w/w basis, both species utilize from 5 to 10 times as much water as food. Water avoidance tests showed that mallards avoided consumption of 1080-contaminated water at concentrations between 13 and 24 ppm. Bobwhite avoided consumption of 1080-contaminated water at concentrations greater than 9 ppm.

Avian dietary toxicity tests were conducted with seven pesticides, two age groups (2 and 16 weeks old) of northern bobwhite (Colinus virginianus) and two durations (5 and 28 days) of exposure. Results were analyzed with an emphasis placed upon comparing mortalities on similar test conditions. An analysis that used the entire dose-time-response results led to the calculation of a common measure (asymptotic rate e) of temporal development of the response surface and served as a basis of comparison of diverse test results. The asymptotic median lethal concentrations were designated by ALC50 and the median lethal concentrations at the end of a test period by LC50. It was found that: (1) Young birds in 5- and 28-day tests were more sensitive to incremental increases in the duration of exposure than adults. (2) Young birds were less sensitive to incremental increases of dietary concentration than adults only in the 5-day test and displayed delayed response patterns in six of seven chemicals in those tests. (3) LC50 values of 5-day tests of young birds were greater than LC50 values of 28-day tests, but the corresponding ALC50s were smaller in 5-day tests than 28-day tests. (4) ALC50s for 28-day tests were lower for young birds than for adults. The analysis based on the whole response surface can be used in the design of experiments, in utilizing less than optimum test results due to difficulties encountered during the test in selecting optimum dietary concentration, in linking results of short term exposure with long-term exposure, and in interpreting results of variable exposure tests on a common basis.

A one-generation reproductive toxicity study and a direct eggshell application toxicity study were conducted using the mallard (Anas platyrhynchos) to assess the toxicity of naturally weathered North Slope crude oil (WEVC), obtained following the Exxon Valdez spill. In the reproductive study, birds were fed diets containing 0, 200, 2,000, and 20,000 mg of WEVC/kg diet. No significant differences (p {le} 0.05) in mortality, body weight, food consumption, reproductive parameters, or hatchling parameters were observed. Significant decreases in mean serum phosphorus, serum total protein, albumin, bilirubin, and calcium concentrations were observed in high-dose-group females; no differences were noted among males. Eggshell strength and thickness in the high-dose group were significantly reduced compared to controls. Trends toward increased liver weights and decreased spleen weights were observed in WEVC-treated birds. Applications of WEVC to developing eggs showed it to be less toxic than unweathered North Slope crude oil. Doses covering up to one-third of the shell area of developing mallard eggs (92 mg) resulted in no effects on developing embryos. Eggs treated with the control material, petrolatum, were adversely affected by applications covering approximately one-sixth of the eggshell (24 mg), suggesting inhibition of gas exchange. Neither material affected hatchling survival or growth.

Food avoidance experiments could contribute to assessments of animals' behavioral responses to environmental toxicants. Food avoidance tests with mallards (Anas platyrhynchos L.) and northern bobwhite (Colinus virginianus L.) as the test species were patterned after avian 5-d dietary LC50 tests. Animals in each treatment group were given free access to untreated feed and feed treated with various concentrations of methiocarb (3,5-dimethyl-4-(methylthio)-phenyl methylcarbamate), a widely used bird repellent. Prior to food avoidance testing, 5-d dietary LC50 tests were conducted to provide baseline data for comparison. A measure of avoidance response was estimated from a log (dose)-probit (response) analysis. The percentage of total (treated plus untreated) feed consumption as treated feed consumption was the response variable. The detectable dietary concentration at which mallards and bobwhite began to avoid a specific contaminant was determined by calculating a median food avoidance concentration 50 (FAC50). In the absence of detectable avoidance behavior, test animals' total feed consumption can be expected to consist of equal amounts of treated and untreated feed. An effective avoidance index (EAI), LC50/FAC50, was used as a measure of a toxicant's “margin of safety.” Calculated results for methiocarb were as follows: for mallard, LC50 = 7,469 ppm, FAC50 = 145 ppm, EAI = 51.5; for bobwhite, LC50 = 827 ppm, FAC50 = 95 ppm, EAI = 8.7.

Feeding adult mink and European ferrets diets that contained 1, 5, or 25 mg/kg added hexachlorobenzene (HCB) resulted in reduced reproductive performance as indicated by decreased litter size, increased percentage of stillbirths, increased kit mortality, and decreased early kit growth. Diets treated with 125 or 625 mg/kg HCB were lethal to the adults of both species. In general, the mink were more sensitive to the toxic effects of HCB than were ferrets.

The effects of two ahemeral light-dark (L:D) cycles on ring-necked pheasant egg production were investigated in this experiment. Three groups of 36 female and 12 male 10-month-old birds were exposed to control 24-hr (14L:10D), ahemeral 22-hr (14L:8D), or ahemeral 26-hr (14L:12D) L:D cycle. Average percent hen-day egg production (HDEP) was 63.8 for hens exposed to ahemeral 26-hr L:D cycle compared with 55.6% HDEP for the controls. Although this was not significant (P less than .05). It suggests a trend for pheasants exposed to ahemeral L:D cycles to improve egg production. Ahemeral L:D cycles did not significantly (P greater than .05) affect egg mass, shell-less eggs, cracked eggs, egg hatchability, and embryonic mortality. Shell quality, measured by specific gravity and shell thickness, was significantly (P less than or equal to .05) reduced for eggs obtained from hens exposed to ahemeral 22-hr L:D cycle. Fertility of eggs from hens kept under ahemeral 26-hr L:D cycle was significantly (P less than or equal to .05) improved compared with fertility of eggs from controls (89.3 vs. 78.4). Results of this research suggest that long ahemeral L:D cycles do play a role in the improvement of pheasant egg production and egg fertility.

In a series of polybrominated biphenyl (PBB) feeding trials in White Leghorn cockerel chicks, the effects of PBB on various physiological parameters and organ weights were determined. These measurements included: growth, thyroid function, ECG, cardiac output, blood pressure, hematocrit, erythropoietin levels, and spleen, bursa of Fabricius, thyroid, testes, comb, liver weights. In addition, tissues were histologically examined. PBB, in the commercial grade form of hexabromobiphenyl, was administered continuously in the diet at levels ranging from 50 to 250 ppm. Pair-feeding studies were conducted to ascertain the effects of the drug per se since preliminary trials indicated that PBB administration resulted in decreased feed intake. Chronic administration resulted in depressed body weight as a result of decreased feed intake; decreased comb, testes, spleen, and bursa weights; increased liver and thyroid weight; hydropericardium and ascites; decreased hematological values due to depressed plasma erythropietin levels; decreased heart rate, packed cell volume, hemoglobin and cardiac output; decreased voltage amplitude of the ECG and a shift in the mean electrical axis. No significant differences were found in blood pressure (mean arterial and pulse pressure), stroke volume, or respiratory rate. Images FIGURE 4. A FIGURE 4. B FIGURE 4. C FIGURE 5. A FIGURE 5. B FIGURE 5. C FIGURE 6. A FIGURE 6. B

Adult female ferrets were found to absorb 85.4% of a single dietary dose of the polychlorinated biphenyl (PCB) mixture Aroclor 1254. Excretion in the days immediately following dosing yielded the greatest quantity of PCBs eliminated in a given time period. In general, urinary excretion represented one-tenth or less of the PCBs excreted via the feces. Placental transfer to the ferret kits was 0.01% (per kit) of the female's absorbed dose when exposure occurred during the first trimester of pregnancy and 0.04% (per kit) when the PCBs were administered during the third trimester. Transplacental exposure to PCBs was considerably less than that reaching the kits through the dam's milk. The ratio of placental to mammary transfer, following 1 week of lactation, was calculated to be approximately 1:15 for the offspring of first-trimester-dosed females and 1:7 for the offspring produced by females treated during the third trimester.

Adult female standard dark mink were exposed to hexachlorobenzene (HCB) at concentrations of 0, 1, and 5 ppm in the feed and bred with males on the same treatments. Female offspring were allowed to mature to 16–17 weeks and killed. At 16–17 weeks of age, HCB had no effect on body weights or liver weights. Hepatic cytochrome P-450 and ethoxyresorufin-O-deethylase were significantly increased 2.0- and 1.5-fold, respectively, in the 5-ppm treatment group. Electron microscopy failed to reveal proliferation of the smooth endoplasmic reticulum. No hepatic damage was observed. No changes in in vitro renal function, measured as accumulation of para-aminohippurate and tetraethylammonium by renal cortical slices, were detected in any treatment group. Histological examination of renal slices did not reveal any alterations in morphology. Fat was the predominate site of HCB disposition; samples from the 5-ppm treatment group contained 626.10 ± 12.01 ng HCB/g tissue. Whereas perinatal HCB administration has profound effects on the survival of off-spring born to exposed mink, only induction of hepatic mixed-function oxidases was observed in the surviving kits without any observable frank hepatotoxicity.

1. 1. Evaporative heat loss (E), O2 consumption, CO2 production and internal body temperature (Tb) were measured in bobwhite (1–65 days of age) at specific ambient temperatures (Ta). 2. 2. tb at ta 25°C increased from 27.6° in 1-day-old quail to 41.1°C in the adult. 3. 3. Improvements in thermal stability are attributed to augmented rates of metabolic heat production (H) and a diminution in total thermal conductance. 4. 4. Inability of immature quail to maintain constant tb is not attributed to excessive rates of E. The ratio of E ti H did not change after day 6, when the major increase in thermoregulatory ability occurred in the quail.

A total of 108 pheasant hens was exposed to either a conventional 24-hr (14L:10D), an ahemeral 22-hr (14L:8D), or an ahemeral 26-hr (14L:12D) light-dark (L:D) cycle. Total lag time for each egg sequence was greater in the ahemeral cycles than in the conventional L:D cycle, resulting in significant (P less than .05) differences in egg formation times (EFT) or intraclutch intervals of 26.4, 25.8, and 27.5 hr, respectively. The EFT under the ahemeral 26-hr L:D cycle was synchronized (within 1.5 hr) with the length of the L:D cycle. This light cycle resulted in the longest egg sequences (average 8.5 eggs per sequence) produced under any of the three L:D cycle treatments due to a shorter pause in oviposition. Values were significantly (P less than .05) different from the average values obtained under the conventional 24 hr L:D cycle (4.9 egg per sequence) and ahemeral 22 hr L:D cycle (3.5 eggs per sequence).

Female mink were fed a basal diet supplemented with either 0, 10 100, or 1000 ppm iodine, as potassium iodide, from breeding through lactation. In addition, females were housed in pens sanitized just prior to whelping with 100 or 1000 ppm titratable iodine disinfectant to investigate the effects of these treatments on their reproductive performance. The gestation periods of the iodine-treated mink were shorter than the controls. Kit birth weights were not significantly different from the controls. The average number of kits whelped per female mated in the control group was 5.0. No detrimental effects were observed on litter size or kit survival in the group fed 10 ppm supplemental iodine. Only 2.1 kits per female mated were whelped by the mink fed 100 ppm supplemental iodine and none of the females that received the 1000 ppm supplemental iodine diet whelped. Body weights of kits whelped and nursed by the females that received the 100 ppm supplemental iodine diet were significantly lighter at 4 weeks of age. Kits nursed by females housed in pens sanitized with 100 or 1000 ppm titratable iodine had the greatest biomass at 4 weeks of age.

The toxicity of a polychlorinated biphenyl (PCB) mixture (Aroclor® 1254) to mink (Mustela vison) was evaluated through three dietary LC50 tests. These tests were designed to assess the effects of age of the test animals, composition of the diet, and season and year on the results of 28-day dietary LC50 tests. A dose-dependent weight loss was noted for animals in all tests and similar dietary LC50s were calculated for all three trials, both at the end of the 28-day exposure period (83, 84, and 79 ppm) and after a 7-day withdrawal period (58, 47, and 49 ppm). Based on all test criteria, age, dietary composition, season, and year had little effect on the outcome of the LC50 tests. The withdrawal period was important in determining the toxicity of Aroclor 1254 and should be considered in assessing the toxicity of other slow-acting, lipophilic compounds.

Hexachlorobenzene (HCB) was found to depress the lymphocyte blastogenic response of mink (Mustela vison) and European ferrets (Mustek putorius furo) to the plant lectin Concanavalin A (Con-A). A significant reduction in the incorporation of [3H]thymidine was seen in the lymphocytes from adult animals consuming 25 ppm dietary HCB for 8 months. This effect was observed in animals showing no physical signs of distress or toxicity. The in utero and early postnatal exposure of young mink to HCB also resulted in a significant depression of lymphocyte responsiveness. Exposure levels as low as 1 ppm in the dam's diet caused an impaired T-cell response. In the young ferrets exposed to HCB in utero and during nursing, no change in the stimulation index was seen. The monitoring of immunocompetence in animals exposed to toxicants, either through the diet or indirectly via their dam, provides a sensitive indicator of toxicity. Effects were seen in activation of lymphocytes from the mink and ferrets used in this study without grossly observable clinical signs being present.

The effect of dietary PCBs (50–200 ppm) on some cardiovascular and hematological parameters in the SCWL cockerel was investigated. Heart rate was significantly reduced by PCB 1242 and 1254 at ≥100 ppm and was not altered by PCB 1221 or 1260 at 150 ppm. A significant decrease in arterial blood pH was observed with PCB 1254 at 150 ppm. Mean blood pressure was unaffected by any treatment used. Hemoglobin concentration, HCT, and total erythrocyte count were found to be significantly decreased by PCBs 1242 and 1254 at ≥50 ppm. These same parameters were not affected by PCB 1221 or 1260 at any level used. It was concluded that the anemia observed was due solely to a decrease in total erythrocyte concentration. The possibility that these changes may be due to a decrease in erythropoiesis is discussed. Pericardial fluid volume was increased with PCBs 1242 and 1254; however, there was no correlation between the magnitude of the bradycardia and the amount of pericardial fluid.

The shell quality of eggs produced by northern bobwhite (Colinus virginianus) dosed with sulfanilamide was evaluated by a compression breaking strength test and by the shell thickness measurements that are used in the U.S. Environmental Protection Agency avian reproduction test to determine the effect of a chemical substance on eggshells. The relative sensitivities of the two methods in detecting shell quality changes in sulfanilamide-treated quail were compared by relative response ratios, calculated as treatment period response divided by pretreatment values. The ratios demonstrated a clear shell weakening response and a less apparent shell thinning response. Significant differences in shell thickness of eggs from sulfanilamide-treated hens and those from control hens were not demonstrated (α = 0.32 and 0.34), although highly significant differences in shell strength were demonstrated (α < 0.0001). Scanning electron micrographs of weak shells of normal thickness revealed abnormal ultrastructure, usually poorly formed mammillae. Obtaining both shell thickness and shell strength information may provide better means to evaluate a chemical's effect on shell quality.

Food and water avoidance experiments were conducted on mallards (Anas platyrhynchos L.) and northern bobwhite (Colinus virginianus L.) exposed to a range of dietary carbofuran concentrations. A dietary avoidance concentration 50 (analogous to an LC50) was calculated for each avoidance experiment. This statistic describes the dietary toxicant concentration threshold at which, when exceeded, exposed animals are likely to discriminate between untreated and treated feed or water. The food avoidance concentration 50s (FAC50s) for mallards and bobwhite were 10 and 159 ppm, respectively. The water avoidance concentration 50 (WAC50) for mallards was 3 ppm. For bobwhite the WAC50 for carbofuran was estimated to exceed 50 ppm.

Previous researchers have indicated that birds possess an inelastic arterial tree with a high aortic pulse-wave velocity. The present study establishes the pressure-radius and pressure-volume relationships of thoracic and abdominal aortic segments of chickens and mallards. Each segment was affixed to rigid tubing such that the length could not change. The segment was filled with saline at constant flow by an infusion/withdrawl pump to an intraluminal pressure of 300 mm Hg. The pressure-volume curves for the thoracic segments were sigmoidal with greatest compliance in the physiological pressure range. The abdominal segments were less compliant than thoracic segments. Incremental pulse-wave velocities in the physiological pressure range, calculated from the pressure-volume curves, were similar to those of mammals, i.e., 6 to 10 m/sec. Turkey aortic pulse-wave velocities in the physiological pressure range were calculated from pressure-volume curves in the literature as 8 to 12 m/sec. Thus, the pulse-wave velocities of turkeys, chickens, and ducks are similar to mammals.

This investigation was undertaken to study the acute oral toxicity of PBB to Bobwhite Quail (Colinus virginianus). The median lethal dietary concentration (LC/sub 56/) of PBB was determined over 8 days and clinical signs of intoxication are described.

Ten sexually mature male ferrets were electro-ejaculated at 1, 3 and 5-day intervals to ascertain the effects of ejaculation frequency on semen quality. Semen volume, spermatozoa concentration, spermatozoal motility, as well as the number of stimuli required to obtain an ejaculation were recorded. No significant differences in these parameters were noted between the test intervals for 1 to 3-year-old males. The data indicated that male ferrets from 1 to 4 years of age may be ejaculated as frequently as once per day for short periods of time without any apparent adverse effects on semen quality.

The toxicity of sodium monofluoroacetate (Compound 1080) to mink (Mustela vison) and European ferrets (Mustela putorius furo) was evaluated through LC50 and reproduction tests. Subacute dietary exposure to Compound 1080 resulted in dose-dependent decreases in body weights and feed consumption in both species. The mink were more sensitive to Compound 1080 than were the ferrets. The 28-d dietary LC50 for mink and for ferrets was calculated to be 3.2 and 9.4 ppm, respectively. Dietary exposure to 0.80 ppm Compound 1080 for 2 months prior to breeding severely impaired reproduction in the mink, which was presumed to be due to oligo- or aspermia. In young, rapidly growing ferrets, red and white blood cell counts were adversely affected by dietary concentrations of Compound 1080 as low as 1.08 ppm. The 28-d LC50 test, however, revealed that young, rapidly growing animals may be unsuitable for tests of this duration unless precautions are taken to assure that they do not “outgrow” potentially lethal concentrations of the test chemical.

We have recently reported that hemorrhage to a mean arterial blood pressure (MABP) of 50 mm Hg in the chicken has no effect on total peripheral resistance or skeletal muscle vascular resistance (judged from changes in limb perfusion pressure (P,) during constant blood flow). In the present study we report the effect of a more severe hemorrhagic hypotension (MABP = 25 mm Hg) on skeletal muscle vascular resistance in the constantly perfused hindlimb of the chicken following severance of the sciatic nerve trunk, bilateral cervical vagotomy, a-adrenergic blockade, or during artificial perfusion of the head with arterial blood. Concentrations of serotonin (SER), dopamine (DA), and norepinephrine (NE) in plasma were determined at different levels of hypotension. While hemorrhage to MABP = 50 mm Hg had no effect on P,, a further hemorrhage to MABP = 25 mm Hg produced a sharp rise in P, which was unaffected by severance of the sciatic nerve truck or bilateral cervical vagotomy. This vasoconstriction could be completely eliminated by intraarterial infusion of phentolamine or by pump perfusing the head during the hypotensive interval. Furthermore, concentrations of SER, DA, and NE were significantly elevated only when the rise in P, was evident. We conclude that the vasoconstrictor response to severe hemorrhagic hypotension in the chicken is primarily mediated by an increase in circulating catechol- amines due to cerebral ischemia, rather than a baroreflex.

The toxicity of o-cresol to mink (Mustela vison) and European ferrets (Mustela putorius furo) was evaluated through dietary LC50 and reproduction tests. Twenty-eight-day LC50 tests with each species resulted in no overt signs of toxicity or mortalities, with the highest dietary concentrations being 2,520 ppm for mink and 4,536 ppm for ferrets. Mink were more sensitive to o-cresol than were ferrets, based on feed consumption, body weight data and hematologic parameters. Both species routinely consumed in excess of the estimated oral LD50 in an average day's feed consumption at the highest dietary concentration. Mink in a reproduction test exhibited no significant adverse effects at dietary concentrations as high as 1,600 ppm over 6 months.

INTRODUCTION OSTMANN et al. (1963) found that feathers were loosened by both local and general anesthetics by tranquilizing drugs such as chlorpromazine and promazine and by the neural blocking drugs atropine and yohimbine. On the other hand, adrenergic and cholinergic drugs had no effect on altering feather pulling force. In addition, Ostmann et al. (1964) observed that all levels of spinal transaction significantly reduced feather pulling force posterior to the level of transection. The present investigation was undertaken to determine if the feather muscles have adrenergic (alpha and/or beta) and cholinergic receptors. In addition to the above, the effects of feather muscle receptor stimulation on intrafollicular pressure, feather release and feather shaft movement were also studied. METHODS The pressure within the feather follicle (intrafollicular pressure or IFP) was measured using a technique developed by Peterson and Ringer (1964). Non-molting mature S. C. White Leghorn-type hens were used throughout the experiments. . . .

This experiment was an attempt to define the volume–pressure relationships of the untreated turkey aorta and to evaluate the effect on these relationships of treatment with beta-aminopropionitrile (BAPN) and ascorbic acid. Distensibility values (ΔV/ΔP) were calculated for each of three linear segments of the volume–pressure curve for treated and untreated thoracic and abdominal aortas. In general, the distensibility of the thoracic aorta was greater than that of the abdominal aorta. In both aortic segments addition of BAPN to the ration tended to increase, whereas the addition of ascorbic acid tended to decrease distensibility. The volume–pressure curve of the thoracic aorta was sigmoid in nature and demonstrated the greatest distensibility in the normal physiological systolic blood pressure range of the male Broad Breasted Bronze turkey. Both aortic segments exhibited hysteresis and an isobaric volume change upon successive loading. These phenomena decreased in magnitude with successive loadings.

Two experiments were conducted to study the influence of vitamin A on atherosclerosis. In one experiment quail chicks (Coturnix coturnix japonica) were hatched and immediately placed on diets deficient in vitamin A (880 U.S.P. units/kg. of feed), normal in vitamin A (4,400 U.S.P. units/kg. of feed) or excessive in vitamin A (22,000 and 220,000 U.S.P. units/kg. of feed). In a second experiment, mature male quail were placed on the same diets as in the preceding experiment. All experiments were conducted for 10 weeks. At the end of 10 weeks on experimental rations, blood pressure was measured by cannulation of the carotid artery. The results indicate that birds fed low levels of vitamin A had the highest incidence of coronary atherosclerosis and most severe aortic atherosclerosis. It was determined that a minimum of approximately 15,000 U.S.P. units of the vitamin were needed to minimize atherosclerosis in the thoracic aorta in growing quail chicks. Blood pressure was not significantly altered by varying vitamin A in the diet.

GATES (1946) records a number of human pedigrees showing a high incidence of hypertension which suggested a relatively simple mode of inheritance. More recent studies, however, suggest a complex mode of inheritance and moderate or relatively low heritability. Pickering (1955) who reviews the more recent data indicates a heritability of from 20–23 percent for blood pressure in humans. Alexander, Hinshaw and Drury (1954 Alexander, Hinshaw and Drury (1956) who selected and bred hypertensive rabbits were able to increase level of pressure in the progeny but did not estimate the heritability. Sturtevant (1953) was unable to change mean pressure in rats after two generations of selection for hypertension, but he did report a significant decrease in the variability of pressure. In previous reports it was shown that in unselected populations of chickens, there was a wide range in blood pressures (Sturkie, Weiss and Ringer, 1953, 1956). This range in variability suggested the possibility and feasibility …

INTRODUCTION MANY labels have been tested as indicator substances (Browne, 1922; Bergeim, 1926; Hoelzel, 1930; Henry et al., 1933; Forbes and Garrigus, 1948; Reid et al., 1952; Imabayashi et al., 1956; Mueller, 1956; Hollis and Thompson, 1958; and Tuckey et al., 1958). But the most widely used marker is chromic oxide which was first suggested by Edin (1918) for use in digestion trials. It has since been used in nutritional studies of pigs (Moore, 1957), man (Irwin and Crampton, 1951), cattle (Smith and Reid, 1955), sheep (Johnson et al., 1964), Japanese quail (McFarland and Freedland, 1965), and poultry (Hill and Renner, 1963). Recently, however, radioactive chromium (51-Cr) has been found by several investigators to be useful for digestive studies with mammals. Alternative methods for energy metabolism studies do not use inert food markers. The total collection technique for determining the metabolizability coefficient of a diet can be employed (Kendeigh, 1949; . . .

SCHILLING and Strong (1955) characterized the toxic principle found in sweet pea seeds (Lathyrus odoratus), which produced lathyrism in rats, as beta (N-gamma-L-glutamyl) aminopropionitrile. Barnett et al. (1957) likened the natural occurring condition of dissecting aneurysms (aortic rupture) in turkeys to the dissecting aneurysms observed in rats following the artificial induction of lathyrism by B-aminoproprionitrile (BAPN) feeding. These later workers demonstrated that levels of 0.0313 and 0.04 percent BAPN incorporated into the feed of day-old poults resulted in death as a result of aortic rupture in 15 percent and 33 percent of the poults prior to 28 days of age. Ringer and Rood (1959) reported that the Broad Breasted Bronze turkey has an extremely high normal blood pressure level and suggested that the hypertension may contribute to field cases of aortic rupture in turkeys. Ringer (1959) postulated that the lowering of blood pressure in the turkey by the use of…

ARTERIOSCLEROSIS of aves is similar to that seen in humans (Katz and Stamler, 1953). The normal spontaneous development of avian arteriosclerosis and the ease with which cholesterol can induce this condition have promoted the study of arteriosclerosis in birds. Lofland and Clarkson (1959) studied spontaneous atherosclerosis in pigeons. These workers found Racing Homers and Show Racers to be resistant to atherosclerosis while the White Carneau and Silver King had a high incidence of spontaneous atheromatous lesions in the aorta. The weight and cholesterol content of the aorta paralleled the severity of the disease while the serum cholesterol level was unrelated to the incidence and severity. Aortic rupture, a condition of considerable importance in Broad Breasted Bronze (BBB) turkeys, involves spontaneous aortic atherosclerosis as a possible contributing agent in its development (Carnaghan, 1955). Hemodynamic changes (Ringer and Rood, 1959) have been implicated as contributory agents in the aortic rupture syndrome. Katz …

Methenamine silver, used to detect glycoprotein or mucopolysaccharide, has been applied in this study to Japanese quail (Coturnix coturnix japonica) aortas fixed for transmission electron microscopy. Stainless steel or titanium grids proved to be satisfactory for handling sections. In the procedure outlined in this paper, silver precipitation was prevented by leaving the staining vessels uncovered.

RECENT reviews by Cohen et al. (1964), Kitay and Altschule (1954), Relkin (1966) and Wurtman and Axelrod (1965) describe the progress in pineal research. Little work has been done to elucidate the function of the pineal gland in avian species. Shellabarger (1952 Shellabarger (1953) and Shellabarger and Breneman (1949) did some early work on pineal physiology in chickens. The function most often ascribed to the pineal is an inhibitory action on gonadal development in immature animals or in animals maintained under short daily periods of light. Hoffman and Reiter (1965a, b) recently showed that pinealectomy prevented the usual atrophy of the testes of adult hamsters kept under daily photoperiods consisting of one hour of light and 23 hours of darkness for a period of 4 weeks. Sham-operated controls showed complete testicular atrophy. Since the gonads of birds are known to atrophy in response to short day lengths, a study of the…

In order to establish the age and manner in which the sex difference in blood pressure of the adult white leghorn chicken develops, periodical blood pressure measurements were made on chicks between 3 and 34 weeks of age. There were no consistent differences in pressure between the sexes under 8 weeks of age. Between the 8th and 13th weeks, pressures began to diverge, and within 4–8 weeks a 26–30-mm sex difference in systolic pressure developed. Significant divergences occurred also in diastolic and pulse pressure. The sex divergence was due primarily to a rise in male pressure, the female level remaining comparatively stable. Net changes in male parameters during the period of rapid development of the sex difference in pressure were: body weight + 219 gm, systolic pressure + 26 mm, diastolic pressure + 16 mm and heart rate –22/ min. The age at which the sex difference in pressure begins and its rate of development appear to be related to sexual maturation in the male. However, no significant correlation between the rising male pressure and testes or comb size could be shown. Normal chick blood pressure values prior to the sex divergence differ within strains of white leghorns and for the two groups used here, between 7 and 9 weeks of age, were 150/130 and 162/136 mm Hg.

Two experiments were designed to investigate the development of temperature regulation in Bobwhite quail. In experiment 1, eight groups of chicks were tested at 1, 3, 5, 10, 15, 20, 25 and 30 days of age. Body temperatures showed a curvilinear trend, increasing from 1 to 20 days and then decreasing to 30 days of age. Body temperature within some groups also increased with testing order of the chicks and this effect interacted with age. In experiment 2, one group of chicks was tested at each of the above ages. After determination of body temperature, each chick at each age was cooled for 30 minutes at 24° C. and its body temperature again recorded. The same curvilinear trend in body temperatures with age was evident in this group; however, an increase in body temperature with testing order only occurred at 5 days of age. When cooled, chicks showed a decrease in body temperature of approximately 9°C. at 1 day of age and were able to maintain body temperature by 30 days of age.

THE physiological factors involved in the formation of the albumen, shell membranes and shell of the avian egg have been the subject of numerous researches and controversies. For reviews consult Burmester (1940), Romanoff and Romanoff (1949), Warren (1949), and Sturkie and Polin (1953). Soon after ovulation, the ovum is picked up by the infundibulum of the oviduct. Shortly thereafter, it is forced into the magnum or upper part of the oviduct, where all the protein of the albumen is formed. After the egg leaves the magnum, water is added to the albumen, so that by the time the egg is laid, the volume of albumen has been approximately doubled without added protein. Most observers believe that the albumen is secreted by two types of gland cells in the magnum. Histological studies indicate that the large goblet cells of the unicellular glands secrete mucin fibers, the constituent that makes the albumen …

The cardiac output of untreated mature male Broad Breasted Bronze (BBB) turkeys was determined by an isotope dilution technique using radioactive phosphorus (P32). A Geiger–Mueller tube was connected to a rate meter which in turn was connected to a moving graph to continuously record the indicator concentration, thus obtaining the initial dilution curve. Posterior tibial and common carotid arterial blood pressures were measured directly and were recorded simultaneously with the cardiac output determinations by means of two strain gauges connected to a recording polygraph.From the cardiovascular measurements systemic resistance was calculated. The mean cardiac output of the mature male BBB turkey was 231 ml per kg body weight0.734 per minute. The mean carotid hemodynamic parameters were: systolic BP, 302 mm Hg; diastolic BP, 204 mm Hg; and pulse pressure, 98 mm Hg. Heart rate was 149 beats per minute. The mean tibial hemodynamic parameters were; systolic BP, 286 mm Hg; diastolic BP, 200 mm Hg; and pulse pressure, 85 mm Hg. The mean systemic resistance units were 0.17 and 0.16 for carotid and tibial arteries respectively on a bird basis and 1.13 and 1.08 respectively per kg body weight0.734.

Japanese quail, housed one to a cage, were exposed to reduced living areas caused by an accumulation of their own eggs. After an average of 14 eggs had accumulated, these birds began to destroy their eggs at the same rate they laid them. The effect was to maintain about .026 m.2 of clear floor area. No changes in egg production were found. Behavioral control of living space is suggested by these results.

CCLUSION of both the carotid and ver­ tebral arteries has been shown not to be fatal in all animals tested. This, of course, indicates that collateral circulation is capable of supplying the head with sufficient blood to sustain life. Taylor and Page (1951) ligated both common carotid and vertebral arteries in eleven dogs. Ten of the dogs lived; how­ ever, they appeared dazed, listless and often not interested in food or drink for several days after ligation. Bunce (1960); ligated and then sectioned the carotid and . vertebral arteries in fourteen dogs as fol­ lows: seven dogs, both common carotids and vertebrals; two dogs, both common carotids; two dogs, both vertebrals; two dogs, both internal carotids and vertebrals; one dog, both common carotids and one vertebral. All of the dogs lived for at least four months, but the seven animals with both common carotids and vertebrals sec­ tioned showed impaired intelligence and alertness, poor physical condition, marked emaciation, loss of hair and edema of the extremities. The remaining seven dogs ap­ peared normal in all respects. In contrast to the studies with dogs, Linzell and Waites (1957) reported that after tying off the common carotid and vertebral arteries in anesthetized goats or sheep the cardiac, vasomotor and respira­ tory centers remained functional only up to one hour. The study reported herein was undertak

A PREVIOUS report by Ostmann, Ringer and Tetzlaff (1963) indicated that anesthetics, sympathetic and parasympathetic blocking agents, and tranquilizing drugs caused the feather to loosen within its follicle. These workers did not clarify the exact role played by the muscles and wall of the feather follicle in feather release. An experiment using intrafollicular pressure as a measurement was designed to study the mechanism involved in the loose and tight states within the feather follicle. EXPERIMENTAL PROCEDURE Mature S. C. White Leghorn hens were secured on an operating cradle which held them virtually motionless. A mature feather was randomly selected for studying intrafollicular pressure from either the femoral or caudal feather tract. With procaine used as a local anesthetic, one of the brachial veins was then cannulated for the subsequent injection of sodium pentobarbital. All feather shafts in the immediate area of the chosen feather were cut at the level of…

IT IS thought that the adrenal cortex assumes an important role in an animal’s ability to overcome environmental influences. Therefore, assays capable of indicating adrenal cortical function following changes in management, feed, lighting schedules and weather, among other factors, would possibly be a step toward the elimination of production decreases. Research with rats and guinea pigs (reviewed by Sayers, 1950) has shown that depletion of adrenal ascorbic acid, cholesterol and lipid contents occurs following an injection of pituitary adrenotropic hormone and following stressful conditions such as excessive muscular work or a non-fatal hemorrhage. Reports involving “stressor” agents and their influence on the avian adrenal have been more inconsistent than the reported influence on the mammalian adrenal. Howard and Constable (1958) and Siegel and Beane (1961) produced adrenal cholesterol depletion in chickens following ACTH injection; however, Elton et al. (1959) reported that adrenal cholesterol remained unchanged following ACTH and cold (0–5 …

NUMEROUS reports in the investigational literature demonstrate that certain stress-ameliorating agents may have widespread application and value in the poultry industry where it is deemed desirable to buffer the animal against stress as imposed by adverse environments and alarm stimuli. Carlson (1956) fed reserpine to a mixed group of tom and hen turkeys and observed less fighting; however, weight gains were decreased. Van Matre et al. (1957) found that the survival time of chickens exposed to acute thermal stress could be prolonged significantly by feeding chlorpromazine and reserpine. Both drugs afforded protection against decreases in egg production and shell quality. Burger (1959) and Weiss (1960) confirmed the finding that reserpine (Serpasil) modified favorably the undesirable effects of heat stress in laying chickens kept under laboratory conditions. On the other hand, Burger (1960) reported that Serpasil, at the levels studied, depressed egg production, increased the percentage of floor eggs and accentuated …