Requirements Of Chicks Research Articles

Prefledging mass recession and timing of fledging in Rhinoceros Auklets Cerorhinca monocerata

. First, by provisioning older orheavier chicks, the parental gain in fitness through increasedpost-fledging survival of chicks may be smaller than ifthey provisioned younger or lighter chicks. Parents shouldtherefore induce older or heavier chicks to fledge. Secondly,older or heavier chicks are less likely to remain in theirnests during mass recession because their survival pros-pects should be greater away from the nest than theyshould be for younger or lighter chicks.Parental regulation of provisioning according to the ageand growth of the chick is the key assumption of thesehypotheses. However, parental responses to chick age ormass have varied among experiments carried out onAtlantic Puffins

Manganese and Iron Interrelationship in the Chick

Experiments were conducted to investigate the Mn-Fe interrelationship in the chick. Graded levels of Fe and two levels of Mn were added to a corn-soybean meal diet (157 mg Mn/kg; 372 mg Fe/kg) and to an Fe-deficient casein-dextrose diet containing 15.4 mg Mn/kg and 5.0 mg Fe/kg. Dietary Fe had little effect on the Mn status of the chick, regardless of the level of Fe supplementation. Conversely, Mn supplemented at 1,000 mg/kg reduced blood hemoglobin concentration, but only when the dietary Fe level was at or below the chick's requirement Levels of supplemental Fe up to 2,500 mg/kg had no effect on performance of chicks fed the corn-soybean diet, but a supplemental level of 5,000 mg Fe/kg diet reduced both weight gain and bone ash concentration. These data suggest that the interaction between Mn and Fe in the chick is a unidirectional phenomenon, in which excess Mn impairs Fe utilization but excess Fe does not antagonize Mn.

Effects of protein concentration on responses to dietary tryptophan by chicks

1. Chicks were fed from 4 to 18 d on 40 diets containing all combinations of 8 crude protein (CP) concentrations (from 160 to 300 g/kg) and 5 tryptophan concentrations (from 7.5 to 13.5 g tryptophan/kg CP). 2. At each protein concentration there were responses in growth rate and in efficiency of food utilisation to supplementation with tryptophan. Curves were fitted to estimate the maximum response at each protein concentration. 3. The amounts of tryptophan required (g/kg) for maximum growth and maximum food efficiency were each linear functions of dietary protein concentration. The chick's requirement for tryptophan can be expressed as 12 g/kg CP. 4. It is concluded that a fixed ratio of tryptophan to protein should be specified in practical diet formulation, rather than a minimum dietary concentration of tryptophan.

Blood and Liver Concentrations of Glutathione, and Plasma Concentrations of Sulfur-Containing Amino Acids in Chicks Fed Deficient, Adequate, or Excess Levels of Dietary Cysteine

Experiments were conducted with young male chicks to examine the influence of cysteine status on blood and liver glutathione (GSH) concentrations and plasma sulfur amino acids. The equivalence of cystine, cysteine, and GSH as sources of dietary cysteine for the chick was reconfirmed. Whole-blood GSH was unresponsive to dietary cysteine level, but liver GSH increased as dietary cysteine increased from a deficient level to the required level. Excess levels of cysteine (two or four times the chick's requirement) elicited no further increase in hepatic GSH. Plasma cystine concentration increased markedly (i.e., ninefold) and in a linear fashion while plasma cysteine increased only modestly (i.e., twofold) as dietary cysteine level increased.

Zinc Toxicity, Zinc Deficiency and Zinc-Copper Interrelationship in Eimeria acervulina-Infected Chicks

Three experiments were conducted with young chicks to investigate the effect of duodenal coccidiosis caused by Eimeria acervulina infection on Zn toxicity, Zn deficiency and the interrelationship between Zn and Cu. The coccidial infection depressed both rate and efficiency of weight gain. Dietary Zn addition at 2000 mg/kg depressed performance only slightly, but the 4000 mg/kg reduced both gain and gain/feed markedly. The coccidial infection appeared to have an ameliorative effect on Zn toxicity as assessed by performance and by hematological parameters. Excess Zn (2000 and 4000 mg/kg) dramatically increased liver, pancreas and bone Zn levels. The cocidial infection, however, decreased tissue Zn levels. Copper toxicity caused by feeding 500 mg Cu per kilogram diet was exacerbated by E. acervulina infection. A Zn-Cu antagonism was observed in both control and in coccidiosis-infected chicks. Excess dietary Zn decreased tissue Cu deposition, but excess Cu did not affect tissue Zn deposition. Copper partially ameliorated Zn toxicity symptoms. The efficacy of Cu in overcoming the Zn-induced depressed hematological parameters, however, was enhanced slightly by coccidiosis. E. acervulina infection did not affect the chick's Zn requirement. Growth data were more reliable as indicators of the Zn requirement than were blood or bone parameters.

Eimeria acervulina Infection in the Chicken: Sulfur Amino Acid Requirement of the Chick During Acute Coccidiosis

Five assays were conducted to determine whether Eimeria acervulina infection would alter the chick's sulfur amino acid (SAA) requirement. Chicks were housed in heated starter batteries with raised wire floors and fed completely purified crystalline amino acid diets.With light to moderate E. acervulina infection, data were somewhat inconclusive. In Assay 1, infected birds responded to levels of SAA above those required by healthy birds; but in two subsequent assays, no difference in SAA requirements due to infection could be detected. Therefore, two additional assays were conducted in birds inoculated with a heavy dose of E. acervulina oocysts. In neither of these assays did E. acervulina infection show any indication of altering SAA utilization. When data from the five studies are viewed together, it is clear that E. acervulina infection did not increase the chick's SAA requirement.

The influence of microorganisms and of stress on the chick's requirement for pantothenic acid

1. The responses of germ-free (GF) and conventional (CV) chicks to suboptimal amounts of dietary calcium pantothenate (CaPa) were compared. At the lower levels of supplementation the signs of deficiency were more severe in the CV chicks. 2. Calculations based on mean body-weights of chicks given graded dietary supplements of calcium pantothenate (CaPa) in both environments showed that, to achieve the same body-weight and freedom from signs of deficiency, the GF birds required only approximately two-thirds the amount of CaPa as was needed by corresponding CV birds. 3. Increasing the dietary supplement of CaPa resulted in increased contents of PaA in the livers. GF birds had more PaA per liver than their CV counterparts. In both instances the effect was due to the larger liver size. Concentration of PaA in the liver was not affected by dietary supplement nor by the environment. 4. CV birds were deemed to be under greater stress than GF birds because their adrenal glands were heavier and contained less cholesterol. 5. CV chicks deliberately stressed by injections of adrenocorticotrophic hormone had heavier adrenals with lower cholesterol contents than unstressed controls, but the condition was not altered by increasing the dietary supply of CaPa.

Nutritive value of mixed proteins. 1. In cereal-based diets for poultry.

1. Two series of protein feeding-stuffs each consisting of a fish meal, meat-and-bone meal, soya-bean meal, groundnut meal and sunflower-seed meal were analysed for total amino acid composition and evaluated, both individually and combined in all possible pairs, as supplements to cereal-based diets for growing chicks by the total protein efficiency (g weight gain/g protein consumed; TPE) procedure. Each pair of feeding-stuffs provided 120 g supplementary protein/kg diet and the diet was made up so that the relative amounts of protein provided by each of the pair of constituents were (w/w): 120:0, 100:20, 80:40, 60:60, 40:80, 20:100 and 0:120 respectively, in addition to 60 g protein/kg provided by cereals.2. In all but one of the twenty pairs of feeding-stuffs studied the mixtures exhibited a marked synergistic effect in that the TPE value was higher than the appropriately weighted mean of the TPE values obtained with the individual components.3. Neither chemical score ([amount of limiting amino acid/the chick's requirement for the same amino acid] × 100) nor essential amino acid index; geometric mean for the ratio, amount of essential amino acid: the chick's requirement for that amino acid, for all ten essential amino acids) calculated from the amino acid composition of the dietary constituents could be used routinely to predict the results of the chick growth test, although chemical score did parallel the TPE values in some instances. In a number of instances, mixtures containing an apparently less favourable amino acid composition than one of the components of the mixture gave a higher TPE value.4. It seems likely that the relative proportions of a number of amino acids determine the optimum combination of a mixture of proteins. The removal of amino acid deficiencies alone is not sufficient to ensure that a given mixture of proteins produces optimum performance in growing chickens.

Effect of Feeding “Carbohydrate-free” Diets on the Chick's Requirement for Vitamin B-12

Experiments were conducted to study the effect of fat on the chick's requirement for vitamin B-12 when fat was substituted isocalorically for carbohydrate in a semipurified diet in which protein was supplied by isolated soybean protein and in which methionine was supplied in limited amounts. Using growth as the criterion, the chick's requirement for vitamin B-12 was shown to increase when hydrogenated fat was substituted isocalorically for glucose. Pair-feeding studies showed that vitamin B-12 stimulated growth of chicks fed either carbohydrate-containing or carbohydrate-free diets by stimulating appetite and not by increasing utilization of either protein or energy. J. Nutr. 104: 394-399, 1974.

Effect of Feeding “Carbohydrate-free” Diets on the Chick's Requirement for Methionine

Effect of Feeding “Carbohydrate-free” Diets on the Chick's Requirement for Methionine

Effect of Phytate on the Calcium Requirement of Chicks

THE primary interest in plant-origin phytic acid or phytate in animal nutrition has been directed toward the availability of the phosphorus it contains. Although it has long been known that phytic acid chelates calcium, little or no research effort has been expended to determine the quantitative effect of this compound on the level of dietary calcium needed to supply the chick's requirement for this mineral element. Bruce and Callow (1934) suggested that phytic acid could cause a calcium deficiency in a low-calcium diet. Common (1940) emphasized the significance of phytic acid in the calcium metabolism of the fowl. Both natural phytate in foods and sodium phytate reduced calcium absorption in dogs (Hoff-Jorgensen, 1946) and in humans (Bronner et al., 1954; McCance and Widdowson, 1942a, b; Krebs and Mellanby, 1943; Hoff-Jorgensen et al., 1946a, b).The amount of calcium needed to satisfy the physiological requirement of chicks should, therefore, vary with .

Iron Utilization and Metabolism in the Chick

Experiments were conducted with chicks to determine whether the iron-containing tissues and tissue enzymes show iron deficiency before a reduction in hemoglobin and packed cell volume is obtained. The results indicate that these latter parameters were reduced earlier than myoglobin level, ferritin and hemosiderin iron levels and cytochrome c and succinic dehydrogenase activities. Iron deficiency in the chick was characterized by poor growth, and reduction in hemoglobin, packed cell volume, myoglobin, ferritin, hemosiderin and succinic dehydrogenase activity. The amount of hemosiderin iron exceeded the amount of ferritin iron in both deficient and normal chicks. The ratio of hemoglobin to ferritin plus hemosiderin indicated that after 3 weeks the iron stored in the liver was being utilized for hemoglobin formation by the iron-deficient chick. Nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA), combined equimolarly with iron, had little if any effect on body weight, hemoglobin, packed cell volume, myoglobin and ferritin and hemosiderin-iron in the liver or succinic dehydrogenase activity. When NTA and EDTA were fed in the uncomplexed form in the basal diet or in the diet with 10 mg/kg of added iron, the values for hemoglobin and packed cell volume indicated that the former compound improved iron utilization slightly and EDTA interfered with it somewhat. When body weight, hemoglobin and packed cell volume were used as the criteria, the chick's requirement for iron was found to be 79.0, 77.5 and 77.0 mg/kg of diet, respectively. A realistic estimate of the chick's requirement for iron is, therefore, 75 to 80 mg iron/kg of diet. No evidence was obtained that the soybean protein basal diet reduced the utilization of iron. Thus, the possibility that the phytic acid in the soybean protein interfered with the availability of iron was ruled out.

Changing the chick's requirement of arginine by selection.

Changing the chick's requirement of arginine by selection.

Interrelationship of Plasma Amino Acid Levels and Weight Gain in the Chick as Influenced by Suboptimal and Superoptimal Dietary Concentrations of Single Amino Acids

The concentration of either lysine, arginine or valine was varied over a wide range, in a basal diet containing crystalline amino acids in order to study the relationship between weight gain and the concentration of free amino acids in the blood plasma of chicks. It was shown that the first-limiting amino acid in the diet remains at a very low and constant level in the blood irrespective of the severity of the deficiency. Increments in excess of the amount needed to maximize weight gain resulted in a rapid and linear accumulation of that amino acid in the blood. Since the point at which the amino acid starts to accumulate in the plasma coincides with the break in the growth curve, it is concluded that the plasma technique can be used to determine the chick's requirement for amino acids.

Available Biotin Content of Barley

MOST ingredients used in poultry feeds are considered to contain enough biotin so that biotin supplementation of most practical rations is not needed. The National Research Council's Publication 585 (1958) gives the biotin content of barley as 0.08 milligrams per pound or 0.18 micrograms per gram. This would mean that a ration containing 50% or more of barley should contain adequate biotin to meet the chick's requirement of 0.04 milligrams per pound (National Research Council, 1954). In some of the experiments conducted at this station to study the value of certain enzyme preparations in rations with a new variety of hulless barley, a semi-purified type of diet was fed which contained 75% hulless barley and no added crystalline biotin. Chicks fed this diet developed typical biotin deficiency symptoms, similar to those described by Hegsted et al. (1940), within three weeks. The symptoms did not appear when 100 micrograms of biotin …

Dietary Interrelations Between Methionine, Glycine, Choline, Protein Level and Energy Content of the Chick Diet , ,

METHIONINE and choline have been shown to be beneficial additives to a broiler diet by several workers; however, there are differences of opinion concerning the level required and the degree of response obtained from these materials. Information concerning glycine is even more controversial since workers fail to agree as to whether or not glycine is a beneficial additive. Many workers in the field of nutrition today feel that the requirement of a bird for a given nutrient is not a definite figure, but that it varies with the level of other nutrients in the diet. This is particularly true with respect to protein level and energy content.Rosenberg et al. (1955a) reported that the benefits obtained from the addition of fish meal and methionine together to chick diets, that contained protein levels which were calculated to supply the chick's requirement of sulfur containing amino acids, were greater than would be …

Amino Acid Requirements of the Chick: 2. Effect of Total Essential Amino Acid Level in the Diet on the Arginine and Lysine Requirements

THE chick's arginine requirement is higher when a purified type ration containing casein as the main source of protein is fed, than it is when a practical type corn-soybean oil meal ration is fed. It has been proposed that the practical type diet contains substance(s) which spare arginine. Several substances are known which will increase the growth rate of chicks fed arginine-deficient rations, but no one has claimed that these substances account for the difference in arginine requirement noted on the two types of rations mentioned. Reports supporting these statements have been reviewed in a previous paper on the effect of thyroxine on the chick's requirements for three amino acids (Fluckiger and Anderson, 1959). In the experiments on arginine requirement reported in the previous paper, three different purified type rations were fed. The three rations contained about the same percent protein, but differed in the kind of proteins included. The …

Amino Acid Requirements of the Chick: I. Effect of Thyroxine and Kind of Protein on the Arginine, Methionine and Glycine Requirements

NUMEROUS reports have appeared which indicate that arginine is essential in the diet of the chick. Almquist (1947) estimated the chick's arginine requirement to be 1.2% in a 20% protein diet. A later report by Almquist and Merritt (1950) indicated the requirement to be 6% of the dietary protein in diets with from 15 to 30% protein. Several investigators (Young et al., 1953; Wietlake et al., 1954; Griminger et al., 1955; Snyder et al., 1956; Fisher et al., 1956; Krautmann et al., 1957; and Hogan et al., 1957) have reported that the chick's requirement for arginine is higher than this when fed a diet in which casein provides most of the protein. Snyder et al. (1956) and Krautmann et al. (1957) obtained no growth response by the addition of arginine to practical type corn-soybean diets although they calculated the arginine level of these diets to be below 1.2%. They suggest …

Economies in the use of animal by-products in poultry rations I. Vitamin and amino-acid provision for starting and growing chicks

1. Chicks from commercial sources were housed intensively and fed on a series of rations containing decorticated extracted groundnut meal as the main supplementary source of protein, with and without additions of animal by-products and aureomycin. Parallel groups received rations conforming to Government regulations in their content of sources of animal protein.2. Growth and feed efficiency up to point of lay were as good in groups fed on all-vegetable rations, containing 18% of crude protein in the starting ration and 16% in the growing ration, as in groups fed on regulation rations of the same protein content.3. Performance on the all-vegetable ration up to 6 weeks of age was not as good as on the regulation ration. This inferiority could be largely or wholly corrected by adding extra groundnut meal and condensed fish solubles to the ration. Growth and feed efficiency over the whole rearing period were not improved by the addition of these supplements.4. Addition of aureomycin stimulated growth over the whole rearing period but failed to improve feed efficiency.5. Protein levels in the ration, the provision of animal protein factor(s) and aureomycin were without effect on the age at which laying began.6. Current estimates of the chick's requirement for certain amino-acids appeared to be too high when this type of ration was used.7. The addition of riboflavin to these starting rations was essential. When this was done mortality was low, leg weakness absent and feathering rate normal.