Single Comb White Leghorn Males Research Articles

The hepatic extraction of plasma free amino acids and response to hepatic portal venous infusion of methionine sources in anesthetized SCWL males ( Gallus domesticus)

This study was conducted to investigate the hepatic extraction of plasma free amino acids in anesthetized Single Comb White Leghorn (SCWL) males ( Gallus domesticus). SCWL males were anesthetized and implanted with cannulae in the carotid artery, hepatic vein, hepatic portal vein and the left hepatic duct. Free amino acids in plasma and bile were determined before, during and after 30-min infusions of Saline (control), dl-Methionine ( dl-Met) or dl-2-hydroxy-4-methylthio-butanoic acid ( dl-HMB) into the hepatic portal vein. Hepatic extraction rates (HER) of amino acids were calculated based on the concentration of amino acids in plasma multiplied by estimations of blood flow in the hepatic portal vein, hepatic artery and hepatic vein. For the non-essential amino acids, alanine had the highest HER (46%). The liver also removed more than 20% of hepatic inflow of tyrosine and asparagine with substantial extraction (14–18%) of serine, glycine and glutamine, also. In contrast, less than 5% of hepatic inflow of glutamate and cystine were removed by liver. For the essential amino acids, HER for methionine, histidine and phenylalanine were 30, 14 and 17%, respectively, with less than 5% for branched-chain amino acids, lysine, arginine and threonine. Biliary secretion of amino acids represented a small percentage (<0.2%) of total hepatic extraction turnover of the amino acids. Infusion of methionine sources, dl-Met and dl-HMB, had no effect on hepatic metabolism of amino acids other than methionine. The results demonstrated for the first time, the hepatic extraction of circulating free amino acids in avian species in vivo.

Biliary glutathione secretion in male single comb white leghorn chickens after inhibition of gamma-glutamyl transpeptidase

The amount of hepatic export of glutathione into bile and the importance of gamma-glutamyl transpeptidase (gammaGT) activity for catabolizing glutathione in the bile duct, have not been reported previously for domestic fowl. Therefore, the primary objective of this study was to establish baseline values of biliary glutathione, and a secondary objective was to investigate the effect of acivicin (AT-125; a gammaGT inhibitor) on biliary glutathione in the chicken. Cannulae were placed in the carotid artery (to measure blood pressure) and into the left bile duct of anesthetized male Single Comb White Leghorn (SCWL) chickens (n = 5; 17 to 18 wk). The right bile duct was clamped between the liver and gall bladder. Bile samples were collected at 15-min intervals into microcentrifuge tubes (on ice) containing serine borate and iodoacetic acid to prevent glutathione oxidation. After two samples were obtained to establish baseline values, retrograde infusion of AT-125 (30 microLmol/kg BW) was given to inhibit gammaGT activity in the biliary tree. Systemic blood pressure of the birds remained above 100 mm Hg throughout each experiment (90 to 120 min). Bile flow did not change significantly during the experiment and ranged between 0.15+/-0.03 and 0.20+/-0.07 mL/15 min per kg BW. Baseline biliary secretion values of reduced glutathione (GSH), oxidized glutathione (GSSG), and total glutathione (TGSH) were 4.6, 5.9, and 17 nmol/min per kg BW. After AT-125 infusion, biliary GSH levels increased from 15 to 31 nmol/min per kg BW, indicating that considerable gammaGT-mediated catabolism of GSH occurred in the biliary tree of SCWL males. These results indicate that considerable turnover of GSH in the livers of domestic chickens is due to biliary excretion and that substantial recovery of GSH occurs through activity of gammaGT in the biliary tree.

Analysis of Poultry Fertility Data

Single Comb White Leghorn (SCWL) hens were inseminated intravaginally with spermatozoa from either SCWL or subfertile Delaware roosters in three replicate fertility trials. Overall fertility was analyzed with a log odds model following logit transformation. Duration of fertility was analyzed by iterative least squares. Hens inseminated with spermatozoa from SCWL males laid a higher proportion of fertilized eggs over a longer interval than those inseminated with spermatozoa from affected Delawares. Log-odds and logistic models may have advantages over the more traditional methods of evaluation. This is particularly true in regard to the distribution and normalization of error variances via the logit transformation and removal of nonadditivity via logistic regression.

The Influence of Staining Techniques and Examiners on Evaluation of the Morphology of Fowl Spermatozoa

A total of 53 dwarf Single Comb White Leghorn males from the relaxed selection mating of low and high body weight lines and a randombred control line were used to determine the influence of technique (eosin-nigrosin smears or collection of spermatozoa on membrane filters) and examiner on the assessment of sperm morphology. There were significant (P less than .05) line, technique, examiner, and technique X examiner interactions for sperm abnormalities. Total abnormal spermatozoa were higher in the high line than in the other two lines, and this was associated with increased midpiece defects and twisted spermatozoa. Eosin-nigrosin smears showed almost twice the percentage of abnormal spermatozoa compared to stained membrane filters.

Effect of Caponization on Cell-Mediated Immunity of Immature Cockerels

The effect of gonadectomy was determined on cell-mediated immune response of immature male chickens. Single Comb White Leghorn males were castrated at 3 weeks of age. Response to phytohemagglutinin (PHA) injection as well as graft vs. host (GvH) response were measured at 5, 10, and 15 weeks of age to evaluate cell-mediated immunity. The PHA and GvH responses were inhibited in castrated males. The results suggest that physiological levels of testosterone are needed to stimulate cell-mediated immune response in immature male chickens.

Comparison of Two Direct Bioassays Using Adult Cocks and Four Indirect Methods for Estimating the Metabolizable Energy-Content of Different Feedingstuffs ,

Ninety-six adult Single Comb White Leghorn males were divided into two 48-bird groups to assay feedingstuffs for apparent metabolizable energy (AME) and true metabolizable energy (TME). The metabolizable energy contents of corn, wheat, oats, rye, barley, glucose and soybean, rapeseed, sunflower, dehydrated alfalfa, feather, and fish and meat meals were evaluated. The experiment consisted of three replicates in a cross-over design. The excreta voided by birds in both assays was collected quantitatively at 24- and 48-hr intervals after feeding. A set of corrected AME values (AMEC) was obtained by correcting AME results for endogenous excreta losses. A prediction of AME results was also obtained by using the chemical composition of the 13 feedingstuffs.Birds trained for the AME assay to eat their feed requirements in 1 hr consumed less than ad libitum fed birds even after 14 days of training. Introduction of experimental diets caused a further reduction in intake even though all feeds were pelleted and of similar color. Thirty-nine of 117 AME values were discarded because intakes were less than 50 g/bird. Two TME values were discarded due to problems unrelated to feed. The AME values for the feedingstuffs tested were different (P<.05) from the AMEC and TME results; the latter were not different (P>.05) from each other. Differences (P>.05) in the AME, AMEC, and TME values between the 24-and 48-hr excreta collections indicated that there were differences in clearance rates of feed residues. When AME values were predicted from chemical composition, the error of prediction ranged from .28 to .40 kcal/g, depending upon the equation used.The results of this experiment show that the “rapid method” for AME determinations produces highly variable dat a due to variation in voluntary intake. Although chemical methods provide a more rapid estimation of AME values than bioassays, the results obtained are not reliable.

The Effect of the Age of the Assay Bird on the True Metabolizable Energy Values of Feedingstuffs

Two experiments were made to measure the effect of bird age on the true metabolizable energy (TME) values of four diets. The diets consisted of a basal supplemented with 10% of beef tallow, rapeseed oil, and wheat shorts. In the first experiment broiler chicks aged 24, 38, and 58 days were used as were adult Single Comb White Leghorn (SCWL) roosters. The second experiment was similar, but the birds used were SCWL males aged 29, 43, and 57 days together with adults. The diets used in the two experiments had the same formulations but were prepared from different lots of ingredients.Most of the variance within the TME data was associated with the differences between the diets. Significant age effects were observed within certain diets but they were not consistent. A simple trend with age was apparent in only two instances; these occurred only in the second experiment. Many of the age effects could be explained by the atypical value of a single treatment group within the diet group. It was observed that TME values for adult birds on the same diet were less variable than those for chicks.It seems probable that TME values obtained with adult roosters can be used in the formulation of diets for younger birds; however, additional confirmatory work is required.

Motor Unit Recruitment Pattern in a Respiratory Muscle of Unanesthetized Chickens

THE amplitude of electrical activity of respiratory muscles of the chicken, as recorded with a needle electrode, seems to be related to the level of anesthesia. Fedde et al. (1964) have shown that motor unit potentials of large amplitude are absent when chickens are deeply anesthetized. Since many investigations of the pattern of motor unit recruitment have used anesthetized animals (Sears, 1964; Fedde et al., 1969), we attempted to determine the motor unit recruitment pattern in unanesthetized chickens.METHODSA biopolar, electromyographic electrode (Fig. 1) was implanted in the transversus abdominis muscle (TA) in six, lightly anesthetized (20 mg./kg. of body weight of sodium pentobarbital administered intravenously) Single Comb White Leghorn males, 12 to 16 weeks old. The skin was incised along the ventro-lateral surface of the abdominal wall; then the fibers of the external abdominal oblique and rectus abdominis muscles were separated by blunt dissection to expose the lateral…

Liver, Heart and Adrenal Weights of Broilers Reared Under Constant Temperatures

GARREN and Shaffner (1952, 1956) exposed New Hampshire chicks to 6.7°C. for periods up to 4 weeks starting at 7 weeks of age and found the adrenals larger and the bursa and spleen smaller than in birds at room temperature. Wolford and Ringer (1962) used Single Comb White Leghorn hens and exposed them to 1.7°C. for short periods and concluded that adrenal weights appear to be unreliable as stress indicators in the mature hens. Francis et al. (1967) reared three strains of Single Comb White Leghorn males at 15, 182 and 2,215 meters above sea level and concluded this significantly affected relative heart weight.A study was conducted to determine the development of broilers reared under various constant temperatures from 1 to 56 days of age as measured by liver, heart, and adrenal weights.EXPERIMENTAL PROCEDUREImmediately after hatching, 120 commercial broiler chicks were placed in each of four environmental…

The Relationship of Vitamin K to Mortality from Cecal Coccidiosis

ABSTRACT HARMS and Tugwell (1956) reported that mortality from cecal coccidiosis in chicks could be significantly increased by the addition of dicumarol to the diet. This increased mortality was attributed to prolonging blood clotting time, since the addition of one gram per ton of menadione sodium bisulfite 2 (hereafter referred to as MSB) significantly reduced mortality when added to the diet containing dicumarol. In view of these findings experiments were designed to study the possibility of reducing mortality from cecal coccidiosis by the addition of MSB to a vitamin K low diet. EXPERIMENTAL PROCEDURE Ten pens of males and ten pens of females (Lancaster×New Hampshire) were used in the first experiment. Twenty pens of Single Comb White Leghorn males were used in the second experiment. In either experiment each pen contained twenty, day-old birds. Five experimental treatments were used resulting in four replicates being used with each treatment. Eight pens of birds . . .

Rib Abnormalities in Fowls

EXAMINATION of hundreds of young chicks in making hormone assays revealed that the number of ribs is variable, including deficiencies and additions of portions of ribs. To determine more definitely the nature of these variations, a new series of chicks was examined for this purpose.A total of 522 chicks were examined, 335 of which were Single Comb White Leghorn males and females. The others were crosses of Leghorns and heavy breeds. Of the 522 chicks examined, 89.6 percent were considered normal and 10.4 percent abnormal in rib structure. Chicks from three different hatcheries showed no significant differences in the incidence of abnormalities and there was no difference between males and females.In the usual arrangement, the first two ribs are floating and composed of a single portion each. The next four are articulated to the sternum and each is composed of a dorsal and a ventral portion with a …

Control of the Northern Feather Mite, Bdellonyssus sylviarum, on Chickens in Cages and on Litter

DURING the past 3 years the northern feather mite, Bdellonyssus sylviarum (Canestrini and Fanzago) ( = Liponyssus sylviarum C. & F.), has become increasingly common on poultry farms in Alabama. The increase is probably due to the expansion of the poultry industry in this area leading to the practice of some poultrymen of importing started chicks or adult birds without proper quarantine and treatment for mites.This mite was seen for the first time on the Alabama Agricultural Experiment Station Poultry Farm at Auburn during the fall of 1951, having been introduced on several Single Comb White Leghorn males imported from Mississippi. In a short time all hens that were in contact with these cockerels were infested with the mite. Since several poultrymen in Alabama and adjoining states had experienced difficulty in eradicating this mite from their premises after having tried several recommended measures, it was decided that the miticide …

Morphology of the So-Called “Breast Blisters”

During the past 10 years, breast blisters in chickens and turkeys have aroused interest, but the cause as well as the morphology of these formations is as yet unknown. Apparently, this problem has been approached only from a practical standpoint. As far as this author is aware, the only data available are those of Hodgson and Gutteridge (1941). They concluded that such environmental conditions as types of roosts, size and shape of body, and restriction of feed intake do not influence the development of blisters. However, they state that there is a sex and breed difference, the females of the more common breeds being practically free as are the Single Comb White Leghorn males. The males of the other breeds tested varied in their incidence from year to year.Other observations made by these authors were that, to a certain extent, the genetic constitution of the bird influenced the incidence .