White Leghorn Male Chicks Research Articles

Biological Efficacy of Liquid Methionine and Methionine Hydroxy Analogue-Free Acid in Chicks

An experiment was conducted to determine biological efficacies of DL-methionine-Na (Liquimeth®) and DL-methionine hydroxy analogue (MHA)-free acid (Alimet®) relative to DL-methionine in Single Comb White Leghorn male chicks. A crystalline amino acid mixture devoid of sulfur-containing amino acids was used for the basal diet, and the test substances were added at .1, .2, and .3% levels, equivalent to DL-methionine on a molar basis, in place of cornstarch. By a slope ratio assay using chick growth as a criterion, the relative biological efficacies of DL-MHA-free acid and DL-methionine-Na to DL-methionine were found to be 70 and 113%, respectively, on a molar basis.

Microscopic Postmortem Changes in Kidneys of the Domestic Fowl

Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of postmortem microscopic changes in the kidneys of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. Microscopic postmortem changes in the different segments of the nephron underwent a different rate and sequence of cellular changes. Cellular changes occurred earlier at 29 C than at 18 C and earlier in chickens not wetted with detergent solution. The decrease in body temperature of wetted chickens over dry chickens was significant (P less than 0.05). The proximal convoluted tubule (PCT) underwent the earliest postmortem changes, followed by the distal convoluted tubule (DCT), collecting tubule (CT), medullary loop (ML), medullary collecting duct (MCD), and glomerulus. The PCT, DCT, and thin and thick segments of the ML underwent a sequential nuclear change of chromatin margination, progressive shrinkage, pyknosis, karyorrhexis, and karyolysis. Nuclei were pyknotic if cytoplasmic changes were severe. Primary karyorrhexis was the predominant feature of collecting tubules and ducts. As early as one hour after death, some PCT cells of all kidney sections were pyknotic, emphasizing that immediate tissue fixation was necessary for critical evaluation. By 9 and 18 hr postmortem, PCT of dry and wet chickens, respectively, held at 29 C had pyknotic and karyorrhectic nuclei with slight karyolysis and moderate to marked cytoplasmolysis that extended until 36 hr. At this time, DCT were hardly distinguishable because of loss of basophilia. Karyorrhectic nuclei were already evident in collecting tubules and ducts. At 48 hr postmortem, all tubular cells were non-nucleated with homogeneous, acidophilic cytoplasm. Basement membranes no longer stained with periodic acid-Schiff (PAS). Erythrocytes were pyknotic with unstained cytoplasm. Pyknotic glomeruli were first observed at 9 hr postmortem in dry chickens and 12 hr in wet chickens. Histologic appearance of dry chickens at 9 hr and wet chickens at 18 hr when held at 29 C was similar to that of dry chickens at 12 hr and wet chickens at 24 hr when held at 18 C, with minor differences in some tubular changes. At 18 C, pyknotic glomeruli appeared by 6 hr in dry chickens and 24 hr in wet chickens. Widespread bacterial invasion was noted at 72 hr in dry chickens and at 96 hr in wet chickens.(ABSTRACT TRUNCATED AT 400 WORDS)

Bursectomy and Its Influence on Circulating Corticosterone, Triiodothyronine, and Thyroxine in Immature Male Chickens

This investigation was carried out to determine the effect of bursectomy on circulating corticosterone, triiodothyronine (T3), and thyroxine (T4) in immature male chickens. One-day-old Single Comb White Leghorn male chicks were surgically bursectomized (BSX). Sham-operated chicks were used as control. Blood samples were collected from different BSX and sham birds at 2, 3, and 4 weeks of age. Serum concentrations of corticosterone, T3, and T4 were measured using radioimmunoassays. Serum concentrations of corticosterone and T3 were higher in BSX than sham-operated birds at all ages. Concentrations of T4, however, were similar in both groups. It was concluded that the bursa, directly or indirectly, affected hormone secretion from the thyroid and adrenal glands.

Microscopic Postmortem Changes in Adrenal Glands of the Domestic Fowl

Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of microscopic postmortem changes in the adrenal glands of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. The sequence of microscopic postmortem changes was similar in all chickens except at 18 C, when karyorrhexis of cortical and medullary cells was observed. Cellular changes occurred earlier at 29 C than at 18 C and in dry chickens but not in chickens wet with detergent solution before storage, although slight quantitative and qualitative differences between wet and dry chickens were noted. Medullary cells underwent postmortem changes earlier than cortical cells. Nuclei of medullary cells decreased in size, with chromatin clumping leading to pyknosis, followed by cytoplasmic vacuolation, cellular shrinkage, and finally karyolysis and cell dissociation. Cortical cells had nuclear chromatin marginated, nuclei reduced in size initially, and some nuclear fading, followed by pyknosis and karyolysis. Karyorrhexis was not a prominent feature of cortical and medullary cells, although it occasionally occurred before pyknosis. Cytoplasm of cortical cells remained eosinophilic, granular, and vacuolated, but vacuoles became finer later. Pyknotic medullary cells with vacuolated cytoplasm were observed as early as 3 hr postmortem, regardless of the temperature. Diffuse pyknosis of medullary cells was noted at 18 hr in chickens held at 29 C and at 48 hr in chickens held at 18 C. Marked cortical pyknosis was noted only at 36 hr in wet chickens held at 29 C, when bacterial invasion started. Dry chickens held 36 hr at 29 C had diffuse cellular dissociation, karyolysis and cytoplasmic acidophilia, and marked bacterial invasion. Erythrocytes were pyknotic and had cytoplasmolysis. It was concluded that adrenal glands may still be useful for histopathological examination before 18 hr at 29 C and before 48 hr at 18 C.

The valine, leucine and isoleucine requirements of white Leghorn chicks.

The requirements for leucine, isoleucine and valine were determined in 8- to 18-d-old White Leghorn male chicks. The requirements were estimated from body-weight gains. The estimated requirements for leucine, isoleucine and valine were 200, 115 and 125 mg/bird d, or 12.0, 5.0 and 8.0 g/kg diet, respectively. In terms of concentration in the diet, they are broadly similar to results for broiler-type chicks. When body-weight gain was plotted against daily intakes of each amino acid, significant (P less than 0.01) quadratic regression equations were obtained. The equations showed some characteristics of the individual amino acids.

Nutritional value of earthworms and grasshoppers as poultry feed.

Using 72 one-week-old male White Leghorn chicks, an attempt was made to study whether or not earthworms and grasshoppers can replace fish meal in chick diets.Earthworms had protein content as high as and amino acid content similar to fishmeal except the content of methionine, glycine, valine and proline. Crude protein of grasshoppers was much higher than that of fish meal but its amino acid content was lower. The digestibility and feeding experiment showed that earthworms can be practically used for poultry feed as a dietary protein source. Although it is suspected that the protein would be further improved by supplementing methionine. The TDN level and the ME level of lyophilized earthworms were 81.9% and 3.76kcal/g, respectively. There were little differences in weight of organs (liver, kidney, muscle, spleen and pancreas) among the chicks fed earthwrms, grasshoppers and fish meal.

Colestipol and energy restriction as an approach to hasten removal of PBBs from chickens.

Male White Leghorn chickens were fed either 0.1 or 1.0 ppm fireMaster FF-1 (FF-1) for 21 d. During the withdrawal phase, the chickens were fed 0, 0.5, or 2.5% colestipol hydrochloride, and anion exchange resin. Also, calories were restricted to 80% of control intake within certain groups during the first 14 d in each of 2 consecutive 21-d withdrawal periods. In the caloric-restricted groups, colestipol was fed at 0, 0.625, or 3.125% to yield equal daily intake of colestipol to those fed 0, 0.5, or 2.5% concentrations. During the first 21 d of withdrawal, colestipol at 2.5-3.125%, but not 0.5-0.625%, hastened excretion of polybrominated biphenyls (PBBs) by 50%. During d 22-42 of withdrawal, a background level of PBBs contamination was detected, which tended to confound the results. Despite this, higher levels of colestipol lowered overall body burdens of PBBs by 80% in comparison to the overall level of residues in the other groups of chickens, and by 20% in comparison to their own levels 21 d earlier. Dietary colestipol resulted in chickens with lower carcass lipid content. The combination of energy restriction plus colestipol at 2.5-3.125%, which had the greatest impact in reducing body weight gain and carcass lipid, seemed to be the most favorable treatments for hastening excretion of PBB residues.

Laboratory Model with Chicks for Assay of Nutritional Factors Affecting Hepatic Lipid Accumulation in Laying Hens

A laboratory model with chicks is described that is suggested as an assay for dietary factors affecting liver lipid accumulation in laying hens. The model utilizes growing White Leghorn male chicks injected with estrogen. Diets to be tested were fed ad libitum for 4 days following 2 days starvation. Liver lipid deposition was increased with increasing level of estradiol injected. Lipid deposition in livers of estrogenized chicks fed a diet containing fish meal, alfalfa meal, and torula yeast (FAY) was significantly less than that in chicks fed a corn-soybean meal (CS) diet. This correlated with a similar response in laying hens fed ad libitum FAY and CS diets for 30 days, suggesting the response of livers to dietary changes in fasted-refed-estrogenized chicks reflects the responses obtained with laying hens. Using the proposed laboratory model, fish meal, distillers dried grains with solubles, and alfalfa meal were shown to contain activity that reduced liver lipid deposition

Hepatic lipid deposition and plasma transaminase activity influenced by oral administration of carbon tetrachloride in growing chicks.

Lipid and triglyceride contents in liver and plasma, and plasma transaminase activities were determined in growing White Leghorn male chicks orally administered with carbon tetrachloride (CCl4). Fourteen day administration of CCl4 at rates of 2.5, 5 and 10ml/kg body weight and the single administration at rate of 15 to 30ml/kg body weight increased, with increasing CCl4 doses, liver weight, total lipid and triglyceride contents in the liver, plasma triglyceride concentration and plasma GOT activity but reduced body weight gain and plasma total lipid concentration. Seven out of eight chicks died by 14 day administration of 10 ml CCl4. The maximum increase of the hepatic lipid deposition was demonstrated at 2 or 3 days after whereas that of plasma GOT activity was observed at 1 day after the single administration. It is suggested that a large dose of CCl4 in chicks induces degeneration of hepatic cells, subsequently leading to the hepatic lipid deposition.

Hypothyroidism and antibody production in immature male chickens.

This study was conducted to determine if hypothyroidism has an effect on humoral immunity in immature male chickens. Two week old Single Comb White Leghorn male chicks were used as experimental animals. Two experiments were conducted using different methods to induce hypothyroidism. In Experiment 1, birds were surgically thyroidectomized (Tx group) and in Experiment 2, hypothyroidism was induced by supplementing the feed throughout the experiment with 0.1% propylthiouracil (PTU group). Antibody production against sheep red blood cells (SRBC) (thymus-dependent antigen) and Brucella abortus (BA) (thymus-independent antigen) was tested at 4 weeks of age. Serum concentrations of T4 and T3 were measured in birds from each treatment group at 5 and 9 weeks of age. Body weights were recorded and birds were then autopsied and thyroid gland weights were measured. Hypothyroidism was successfully induced in both Tx and PTU birds, as reflected by significant reduction in body weights in both groups, enlargement of thyroid glands in PTU birds and absence of thyroid glands in Tx birds. Though T4 and T3 were reduced in sera of treated birds, considerable amounts of these hormones were detected. Hypothyroidism did not seem to have profound or consistent effects on antibody production against SRBC or BA. The possibility that thyroid hormones play a role in antibody production was not ruled out. However, it was suggested that within the physiological range of thyroid gland activity, thyroid hormones may not significantly regulate antibody production.

Effects of Dietary Excess Tyrosine and Level of Feed Intake on Nitrogen and Energy Utilization in Chicks

The present study using 8-day-old White Leghorn male chicks, was made to determine whether retarded growth of chicks fed a tyrosine excess (Tx) diet ad lib was due to the depression in feed intake or the reduced efficiency of feed utilization. A Tx diet was prepared by supplementing a 20% crude protein basal diet with 5% L-tyrosine. The levels of feed intake prepared for 10 days were as follows: 160 (corresponding to the amounts of the basal diet the chick would consume ad lib), 140, 120 (corresponding to the amounts of the Tx diet the chick would consume ad lib), 100, and 80 g per bird. Body weight gain, gainrfeed ratio, and energy retention rate of chicks fed the basal or Tx diet decreased proportionally as the level of feed intake was decreased. The addition of Tx to the basal diet significantly reduced the body weight gain, gain:feed ratio, metabolizable energy (ME) value, and nitrogen and energy retention rates at all levels of feed intake. Body composition was not significantly affected by the addition of Tx to the basal diet at all levels of feed intake. The plasma free tyrosine concentration was markedly increased by the addition of Tx to the basal diet and also with increments in feed intake. Dietary Tx per se had a decreasing effect on body weight gain, efficiencies of dietary nitrogen, energy utilization, and ME value. The growth retardation of chicks fed a Tx diet ad lib was due to the combined effects of the depression in feed intake and the reduced efficiency of feed utilization.

Coccidial Infections and Manganese Absorption

Four-week-old Single Comb White Leghorn male chicks were infected with 1,000,000 sporulated oocysts of Eimeria acervulina, or with 50,000 sporulated oocysts of E. necatrix, or with 50,000 sporulated oocysts of E. brunetti, or with 50,000 sporulated oocysts of E. tenella, or were left uninfected as the controls. On Days 1, 3, 6, 10, 14, 21, and 28 following the infection, 5 birds from each group were randomly selected and administered 2.0 μCi of 54Mn orally. At 1, 2, and 4 hr after administration of the radiotracer, the amount of radioactivity appearing in the bloodstream was measured.The absorption of manganese 6 days after the beginning of the E. acervulina infections was decreased to 23 to 34% of that in the uninfected birds, whereas E. necatrix infections resulted in a smaller and more variable decrease in manganese absorption. The other coccidial infections did not decrease manganese absorption significantly. On the 14th day of the infections, all four coccidial infections increased manganese absorption two- to fourfold that found in the controls in one trial but not in the second trial. At other times during the coccidial cycle, no effects were seen on manganese absorption.

Growth, Heart Weight, Cardiac Lipid, and Pathology of Chickens Fed Soybean Oil or Oil Extracted from Different Rapeseed Cultivars

A total of 384 male Single Comb White Leghorn chicks of the Hyline strain were randomized in 24 Petersime battery units of 16 birds per unit. Four replicate pens were fed either a basal (control) diet containing no added oil or a diet supplemented with 20% by weight of either soybean oil or rapeseed oil (RSO) from cultivars Tower, Candle, Regular, or R-500. Levels of erucic acid (22:1) in the RSO's ranged from.1 to 51.6%. Four birds from each unit were killed at 4, 8, 12, and 16 weeks for cardiac lipid analysis and pathology. Feeding RSO had no consistent effect on body weights, heart weights, or the heart-to-body weight ratio. Only the diet containing R-500 (51.6% 22:1) consistently increased cardiac lipid levels as measured gravimetrically. Maximum deposition of the long-chain monoenes (22:1) and eicosenoic acids (20:1) occurred in the cardiac lipids by 8 weeks, and the levels remained high throughout the 16-week trial. The relative concentration of these long-chain monoenes in the cardiac lipids was positively correlated to the dietary levels of these acids. The incidence of lesions found in heart, liver, and skeletal muscle was significantly higher in chickens fed RSO's high in 22:1 than in chickens fed control or soybean oil, and the incidence significantly correlated to the level of 22:1 in the diet. The incidence of heart and muscle lesions and sinusoidal distention in chickens fed RSO's low in 22:1 was not significantly different from that of chickens fed the control diet or soybean oil, but the incidence of hepatic necrosis was significantly higher for chickens fed RSO's low in 22:1 compared to those fed the control diet or soybean oil.

Multiple Regression and Response Surface Analyses of the Effects of Dietary Protein, Fat and Carbohydrate on the Body Protein and Fat Gains in Growing Chicks

Multiple regression analysis of biological response as a function of three factors having a common denominator, on a triangular graph, was investigated for qualitative and quantitative evaluation of nutritional phenomena. As an example of its application, 33 groups of White Leghorn male chicks were isocalorically force-fed purified diets consisting of 5–47% protein, 6–86% fat and 2–89% carbohydrate on a metabolizable energy basis for 10 days, and prediction equations for the body weight gain, protein gain and fat gain were formulated by multiple regression techniques. Perspective views, contour maps and cross-sectional views of the response surfaces constructed from the equations revealed 1) that both body weight gain and protein gain increased with an increase in the metabolizable energy of dietary protein, and were not much affected by the calorie ratio of dietary carbohydrate to fat, showing a convex configuration of the response surfaces; 2) that fat gain decreased and appeared to become more dependent on the calorie ratio of dietary carbohydrate to fat with an increase in the metabolizable energy of dietary protein, giving a combined configuration of convex and concave surfaces, and 3) that dietary protein, fat and carbohydrate were replaceable with one another in the range of 40–50% protein metabolizable energy with respect to body weight gain and protein gain, while replaceability of fat and carbohydrate with each other seemed to decrease with an increase in protein metabolizable energy with respect to fat gain. These results demonstrated that the proposed method is a valuable tool in nutrition studies.triangular graph dietary composition growing chicks multiple regression

Re-evaluation of requirement of Calcium and available Phosphorus for starting meat-type chicks.

Since availability of phosphorus in some of the important feed ingredients of plant origin, such as yellow corn and soybean meal was found to be almost negligible by the bioassay based on toe ash content, re-examination of requirement of phosphorus in Japanese Feeding Standard, which was shown as percent of total phosphorus, was required.In 3 experiments, total 720 one-day-old White Leghorn male chicks were fed diets containing graded levels of calcium from 0.6 to 1.8% and available phosphorus from 0.21 to 1.29% for 3 weeks. Growth responses and toe ash content were determined. By multiple regression analyses, quadratic equation1) to describe the responses of the chicks (y) against dietary levels of calcium (x1%) and available phosphorus (x2%) was obtained, and they=b0+b1x1+b2x2+b11x12+b22x22+b12x1x2…(1)equations were transformed into standard ellipsoidal equations. The response surfaces were given by contour lines. The square root of residual from regression, S, and the maximum response, y, among others were calculated. The responses within the contour line corresponding to ys-S were suspected to be optimum.Two response surfaces for body weight gain and feed intake were quite similar. High levels of dietary available phosphorus, particularly at low levels of calcium, decreased feed intake, resulting in depression of growth rate. This depression of feed intake and growth rate did not change feed efficiency (gain/feed).The maximum toe ash content was calculated to be 15.6%. The contour line corresponding to ys-S, which was 15.1%, indicated that the content will be obtained at the calcium levels over 0.95% and available phosphorus levels over 0.56%. A combination of 1.4% of calcium and 0.56% of available phosphorus was recommended to keep toe ash content of 3-week-old egg-type chicks over 15.1%. If toe ash content could be at least 14%, combinations of calcium and available phosphorus of 1.0-0.35 or 0.8-0.5 were selected to keep growth rate and feed intake maximum.

Effect of dietary energy level on methionine toxicity in chicks.

To investigate the effect of dietary energy level on chicks fed excess methionine, 8-day-old Single Comb White Leghorn male chicks were fed 8 experimental diets for 12 days involving 2 levels of methionine (adequate and 1.5% excess)×4 levels of corn oil (4% to 16% in 4% increments). Supplementation of excess methionine significantly depressed body weight gain, feed intake and utilization of energy and nitrogen, independent of the dietary energy level. Supplementation of corn oil at the expense of corresponding amounts of cornstarch improved the efficiency of nitrogen utilization in both methionine-adequate and-excess diets. However, the growth rate was not improved because feed intake was not accelerated by the additional fat. When the chicks were fed the methionine-adequate diet, feed intake was gradually decreased with the progressive increase in the dietary energy level, so that metabolizable energy intake was kept constant. These chicks required several days to complete the adjustment for energy intake, while the depression in feed intake due to excess methionine was observed within 2 days after feeding.

Influence of ascorbic acid on the adverse effect of feeding a diet containing excess tyrosine to chicks.

1. The effects of dietary or parenteral administration of ascorbic acid on the adverse effects of excess tyrosine were investigated with young male White Leghorn chicks in a 2-week experiment. 2. Addition of 10 g ascorbic acid/kg to the control diet (without excess tyrosine) produced no beneficial effects on performance. Excess dietary tyrosine caused depressions in all measures of performance. 3. Adding 0.1, 1, 10 or 20 g ascorbic acid/kg to the diet containing excess tyrosine tended to improve performance. 4. Subcutaneous injection of 50 mg ascorbic acid/bird d to chicks receiving excess tyrosine brought about a significant improvement in body-weight gain. 5. The elevation of plasma free tyrosine caused by excess dietary tyrosine decreased as dietary ascorbic acid increased. 6. Ascorbic acid can alleviate, though not completely counteract, the adverse effect of excess dietary tyrosine.

Comparison of Brachial Venous and Mixed Venous Blood Gas Tensions and pH Values in the Chicken

Differences in blood gas tensions and pH between brachial venous blood (BVB) and mixed venous blood obtained from the pulmonary artery (PAB) were compared in anesthetized male White Leghorn chickens to determine if BVB as obtained in routine venipuncture could be used to estimate mixed venous values of pO2, pCO2, and pH.When paired samples were compared over the range of 25 to 68 mm Hg, brachial pO2 was 5.7 mm Hg higher (P<.001) than PAB pO2. Brachial pCO2 was 4.25 mm Hg higher (P<.001) than PAB pCO2 over the range of 17 to 56 mm Hg. Brachial pH was .066 units lower (P<.001) than comparable values for PAB over the range of 7.2–7.6 pH units.Regression equations are given for estimating mixed venous blood gas tensions and pH values from blood samples taken from the brachial vein.

A method for the determination of available fluoride from marine products using young chicks.

AbstractA method is described for the determination of available fluoride in biological materials. Groups of 1‐day‐old male White Leghorn chicks were fed a low fluoride diet for 14 days (2.3 mg F− kg−1) to which graded levels of fluoride were added as sodium fluoride, or in the form of fluoride‐containing foods. The drinking water did not contain any detectable amount of fluoride. Water and feeds were provided ad lib. The response was measured as the concentration of fluoride in the three bones of the third toe from both feet on a fat‐free dry matter basis. A linear accumulation was observed for the addition of up to 500 mg F− kg−1 to the diet. An experimental dose range between 0 and 8 mg kg−1 was chosen. The availability of fluoride was measured as the slope ratio between highly correlated regression lines for test material and a standard. The lines had a common intersection on the y‐axis. Relative to sodium fluoride, the biological availability of fluoride from different types of fish protein concentrate showed values of 110‐151%. The corresponding values for krill (Meganyctiphanes norvegica) and a fluoridated toothpaste containing sodium monofluoro‐phosphate were 112 and 145%, respectively.

The Effect of the Thyroidal State on the Immunological State of the Chicken

Effects of the thyroidal state on certain immunological parameters were studied in four groups of male White Leghorn chicks. One group was fed with commercial chick mash and served as control, the second was supplemented with 0.1 % Propylthiouracil (PTU) in food, the third was supplemented with 0.025 % thyroxine in food, and the fourth was supplemented with 0.1 % PTU and 0.025 % thyroxine. Treatment with PTU (29 days) resulted in hypothyroidism evidenced by low T4 level, decreased oxygen consumption rate and decreased weight gain. Thyroxine treated group reached hyperthyroidism shown by high T4 level and increased oxygen consumption rate. When all chicks were immunized with SRBC, hemagglutinating antibody titer of PTU treated group was significantly lower than that of the other group while thyroxine treatment resulted in increased, but statistically not significant titers. At 36 days of age the chicks were killed. PTU treated group exhibited decreased thymus, spleen and bursa weights and low 3H thymidine incorporation after Con A stimulation of both spleen and thymus cells. Thyroxine treatment resulted as well in low 3H thymidine incorporation. These findings indicated that hypothyroidism depressed the immunological system, while hyperthyroidism had no effect on antibody formation but depressed reactivity to Con A stimulation.