Heat production and lipid metabolism in broiler and layer chickens during embryonic development

We compared heat production (HP) and lipid metabolism in broiler and layer chickens (Gallus gallus) during embryonic development. To investigate HP and respiratory quotient (RQ), oxygen (O2) consumption and carbon dioxide (CO2) production were measured using an open-circuit calorimeter system. HP consistently had a tendency (P = 0.06) to be lower in broilers than in layers during embryonic development, and HP gradually decreased with developmental stage in both strains. RQ values of both strains were approximately 0.7 at every embryonic stage investigated. These results suggest that chicken embryos mainly use lipid for energy, and the RQ was significantly lower in broilers than in layers during embryonic development. Consumption of the yolk sac as a lipid source was faster in broilers than in layers. Plasma D-3-hydroxybutyrate (D3HB) and glycerol concentrations, associated with fatty acid oxidation, were lower in broiler than layer embryos. These results demonstrate that HP and lipid metabolism are different between the strains during embryonic development, and may be one factor for the growth difference between broiler and layer embryos.     

Dynamics of free amino acids in rat brain tissue during hypothermia

A comparative study is conducted for the effect of one-, three- and six-hour artificial deep (20-19 degrees C) hypothermia on the content of free amino acids in the blood serum, tissue, nuclei and mitochondria of the rat brain. It is found out that the content is the highest in the blood serum after a three-hour cooling. In the brain tissue the amount of amino acids lowers, especially under conditions of a six-hour hypothermia. In nuclei a three-hour effect of hypothermia decreases sharply the content of free amino acids and the six-hour one increases the amount of most of them. Under hypothermia the content of nearly all amino acids in the brain mitochondria is higher than in the intact animals.     

Role of volatile fatty acids in development of the cecal microflora in broiler chickens during growth

It is known that volatile fatty acids can inhibit growth of species of the family Enterobacteriaceae in vitro. However, whether these volatile fatty acids affect bacterial populations in the ceca of chickens is unknown. Therefore, a study was conducted to investigate if changes in volatile fatty acids in ceca of broiler chickens during growth affect bacterial populations. Results showed that members of the Enterobacteriaceae and enterococci are present in large numbers in 3-day-old broilers and start to decrease when broilers grow older. Lactobacilli are present in large numbers as well in 3-day-old broilers, but they remain stable during the growth of broilers. Acetate, butyrate, and propionate increase from undetectable levels in 1-day-old broilers to high concentrations in 15-day-old broilers, after which they stabilize. Significant negative correlations could be calculated between numbers of Enterobacteriaceae and concentrations of undissociated acetate, propionate, and butyrate. Furthermore, pure cultures of Enterobacteriaceae isolated from the ceca were grown in the presence of volatile fatty acids. Growth rates and maximal optical density decreased when these strains grew in the presence of increasing volatile fatty acid concentrations. It is concluded that volatile fatty acids are responsible for the reduction in numbers of Enterobacteriaceae in the ceca of broiler chickens during growth.     

Changes in blood chemistry in broiler chickens during the fattening period

The aim of the study was to determine the changes in the selected biochemical serum parameters in male Ross 308 broilers during the fattening period. The birds were kept under standard farm conditions and they were fed on commercial mixtures. The blood for analysis was taken from the jugular vein on the 14th, 21st, and 42nd days of age. The concentration of serum protein (total protein, albumins, uric acid, creatinine), lipid (TG, TCHL, HDL) and mineral (Ca, P(i), Mg, Fe) indices were determined. The measurements were carried out with the use of Epoll 20 photometer. The content of LDL and VLDL lipoprotein fractions was calculated on the basis of the Friedewald equation. Most of the estimated parameters, except for LDL and Pi, were age-dependent (P<0.05). Total protein, albumins and total Ca levels showed a constant increase between the 14th and 42nd days of life. A lower (P<0.05) concentration of TG, TCHL, HDL, VLDL, Mg and Fe was determined at the end of the fattening period compared to 14-day-old broilers. A significant decrease of TG, VLDL, Mg and Fe content was noted already in the first age range (days 14-21) while in the case of TCHL and HDL a significant decrease was found between the 21st and 42nd days of fattening. The obtained results may be helpful in the evaluation of changes in the metabolic profile, health condition and production patterns in growing broiler chickens reared under farm conditions.     

Changes of free amino acids in media during the culture of mosquito cells

The utilization of free amino acids in culture media by two mosquito cell lines derived from Aedes aegypti (Peleg, 1969) and Culex molestus (Kitamura, 1970), were studied. Amino acids which showed a marked decrease with increasing period of culture were aspartic acid, cystine, and ornithine in both cell lines. Asparagine and glutamine decreased markedly in Culex cell culture, but only slightly in Aedes cell culture. In contrast isoleucine, leucine, proline, tyrosine and valine decreased more in the Aedes cell culture than in the Culex cell culture. Arginine, glycine, lysine, phenylalanine, serine, threonine and tryptophan did not change significantly in the culture media of either cell lines. α-Alanine increased markedly in the culture of both cell lines. Glutamic acid increased to some extent in the Culex cell culture, but not in the Aedes cell culture. β-Alanine and histidine increased slightly in the Aedes cell culture, whereas they remained almost unchanged in Culex cell culture.     

Changes in the amino acids content of almond buds during their hibernation and development

Auto?i p?edkládají výsledky chromatografického stanovení volných aminokyselin a aminokyselin bílkovinných frakcí rozpustných v ethanolu a louhu, a nerozpustných, v květních a vegetativních pupenech dvou r?zně v??i zimě odolných odr?d mandloně Non-plus-ultra a Voch?aberdi, odebraných v r?zn?ch termínech od podzimu do jara. Chromatografické stanovení aminokyselin v pupenech ukázalo :

1. 1.
   V květních a vegetativních pupenech se projevuje béhem podzimu a zimy dosti dob?e pozorovatelný rozdíl v obsahu a poměru aminokyselin skoro v?ech frakcí. Nejvýrazněj?í rozdíl se projevuje v kvalitativním obrazci a poměru volných aminokyselin a aminokyselin frakcí rozpustnych v ethanolu, slaběji u frakcí rozpustnych v louhu a nerozpustných.     
   
   

Quantitative changes in free amino acids in Polytrichum formosum during development

The concentrations of each free amino acid in Polytrichum formosum have been determined for female gametangia at different developmental stages of     

Analysis of free amino acids in mammalian brain extracts

An optimized method for analysis of free amino acids using a modified lithium-citrate buffer system with a Hitachi L-8800 amino acid analyzer is described. It demonstrates clear advantages over the sodium-citrate buffer system commonly used for the analysis of protein hydrolysates. A sample pretreatment technique for amino acid analysis of brain extracts is also discussed. The focus has been placed on the possibility of quantitative determination of the reduced form of glutathione (GSH) with simultaneous analysis of all other amino acids in brain extracts. The method was validated and calibration coefficient (K _GSH) was determined. Examples of chromatographic separation of free amino acids in extracts derived from different parts of the brain are presented.     

Changes in free fatty acids and diglycerides in mouse brain at birth and during anoxia

Abstract: Within the first few hours of life in the mouse, marked changes were seen in brain endogenous free fatty acids (FFA). A 21% decrease in the total FFA pool occurred during the 1st h of life, and a constant value was maintained thereafter to 10 h. Polyunsaturated fatty acids displayed a different pattern of change. There was 27% less free ararhidonic acid at birth (0 h) than 1 h later. Similar values were obtained for docosahexaenoic acid at birth and at 10 h, although palmitoleic and oleic acids decreased markedly after 1 h. The polyunsaturated fatty acyl chains of diglycerides (DG) showed a statistically significant increase as a function of time after birth, despite an unchanged total DG pool size. The brains of pups subjected to 40 min of N₂-anoxia immediately after delivery exhibited a decrease in FFA, especially the monoenoic components, but 60 min of anoxia yielded higher FFA levels. Anoxia induced at 10 h increased FFA and arachidonic acid was higher than when anoxia was induced at 0 h. FFA accumulation was further stimulated by raising the environmental temperature during anoxia. When anoxia was induced, DG exhibited a net increase in palmitate, oleate, and palmitoleate at 0 and 10 h. No arachidonoyl-DG accumulated at 0 h, even after 60 min of anoxia, and stearate was unchanged at 0 and 10 h. The lipid changes observed in the brain during the first hours of life suggest that the enzymatic reactions that promote accumulation of free arachidonic and docosahexaenoic acids and arachidonoyl-DG in the mature brain are present at low levels at the time of delivery. The sluggish modifications found in our study may be related to the longer resistance of newborns to oxygen deficiency.     

Changes in free and bound amino acids in experimental silicosis.

The amino acid composition of lung, serum and liver in silicotic rats was studied in order to assess the availability of precursors in lung for fibrogenesis. It was observed that the pool of ornithine, arginine, alanine, leucine, valine, glutamic acid, lysine, proline and glycine underwent marked alterations. Free arginine, proline and leucine were only detectable in silicotic lung, while free glycine, glutamic acid and glutamine pools decreased significantly in liver. Changes in amino acid metabolism as a result of silicosis are discussed.     

Metabolism of hibernating reptiles. Changes of free amino acids in blood, liver and brain.

1. Glutamic acid showed a significant decrease during hibernation in brain cortex. This is attributed to: (a) Transformation to glutamine to detoxicate ammonia. (b) The synthesis of GABA from glutamic acid. (c) It is suggested that the enzyme GAD is active during hibernation. 2. GABA showed a significant increase in liver and brain cortex. It was absent in the blood serum. (a) The present results show that non-neural tissues contain lower GABA than neural tissues. (b) GABA may be formed locally in tissues by decarboxylation of glutamate as well as from pathways connected with tricarboxylic acid cycle. 3. Aspartic acid showed increased levels in blood serum, liver and brain cortex, the greatest increase was observed in liver. 4. A significant increase was recorded in the level of arginine in brain cortex and liver, whilst a smaller percentage increase was recorded in ornithine level. It is assumed that transformation of arginine to ornithine was depressed during hibernation.     

Huntington's disease: studies on brain free amino acids

We studied the levels of free amino acids in putamen and Brodmann's area 10 of 12 patients who died with Huntington's disease and 13 non-neurologic controls. GABA, glutamate and alpha-amino-n-butyric acid concentrations were found to be reduced in putamen of Huntington's disease patients. In Brodmann's area 10 the levels of glutamate, histidine and lysine were decreased, but the content of aspartate, GABA, glycine, serine and taurine was increased in the same group of patients.