Wyniki wyszukiwania

1

A morphophysiological conception and model of animal growth

100%

Cherepanov G. G.

Journal of Animal and Feed Sciences

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2001

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tom 10

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nr 3

2

Evaluation of methods used in vivo to estimate the transfer of amino acids and other substrates into the cells of mammary gland

63%

Cherepanov G. G., Makar Z. N.

Journal of Animal and Feed Sciences

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2010

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tom 19

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nr 2

183-194

In recent years some approaches were developed to estimate the parameters of transport of amino acids and other substrates into the cell in vivo using arteriovenous concentration difference and volume blood flow data with their recalculation according to kinetic model of the system: capillary - interstitium - cell. With the use of literature data and the own results the authors analysed the present feasibility of this method in the studies of mammary metabolism in productive ruminants The model estimates were compared with independent measurements (with 13С-amino acids), the verifying experiments were conducted and some unresolved problems and errors of interpretation were investigated. The method is recommended to study the adaptive shifts in the activity of amino acid transport into the mammary secretory cells during milk formation in various nutritional states.

3

Estimation of substrate-energetic fluxes in lactating cows

63%

Cherepanov G. G., Agaphonov V. I.

Journal of Animal and Feed Sciences

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2010

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tom 19

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nr 1

13-23

In this article an algorithm estimating the basic metabolic fluxes in lactating cows is described that uses data of substrates absorption, heat production, respiratory quotient and milk productivity. The flux diagram permits to estimate parameters which are very difficult to measure in physiological experiments, including rates of oxidation of substrates to CO2 and their interconversions (synthesis of long-chain fatty acids from acetate, gluconeogenesis from amino acids, etc.). The developed model was verified in an experiment carried out on two groups of lactating cows with measurements of energy balance, heat production and respiratory quotient (СО2 /О2) during the periods of 40-45, 60-65 and 90-95 days of lactation. The estimates of oxidation rates obtained for amino acids, glucose, long chain fatty acids and acetate do agree with literature data. The analysis of combined data revealed a negative correlation between oxidation rates of glucose and acetate (r=0.91) and between substrate groups (long chain fatty acids + butyrate) and (glucose + acetate) (r=0.75).

Ograniczanie wyników

3 Journal of Animal and Feed Sciences

3 Cherepanov G. G.

1 Agaphonov V. I.

1 Makar Z. N.

2 2010

1 2001

A morphophysiological conception and model of animal growth

Evaluation of methods used in vivo to estimate the transfer of amino acids and other substrates into the cells of mammary gland

Estimation of substrate-energetic fluxes in lactating cows