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| Author(s): |
Letícia Graziele Pacheco
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Jaboticabal. 2022-11-04. |
| Institution: | Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal |
| Defense date: | 2022-04-05 |
| Advisor: | Aulus Cavalieri Carciofi |
| Abstract | |
To develop better study protocols to access protein metabolism, four methods to estimate protein flux was compared in adult and old dogs. The dietary supply of docosahexaenoic acid (DHA), branched-chain amino acids (BCA), and arginine was also evaluated. The first study aimed to investigate and standardize methods of study protein metabolism with stable isotopes. The second experiment compared the methods of 13CLeucine, 13C-Phenylalanine, 15N-Glycine in adult and old dogs. Nutrient digestibility, nitrogen balance, and protein flow were evaluated in a 4 (methods) x 2 (ages) factorial arrangement. The third study compared two diets in adult and old dogs, a control and a test diet supplemented with DHA, arginine, and BCA. A cross over design and a 2 (diets) x 2 (ages) factorial arrangement was adopted. The test diet presented analyzed values of DHA, arginine, leucine, isoleucine and valine 100%, 35%, 72%, 22% and 18% higher, respectively, than the control treatment. In the first study, similar results of protein synthesis and degradation was observed for all evaluated methods (P>0.05). After this experience, the protocol of the stable isotopes’ application was improved for the other studies. On study two, an age effect was observed for protein flow (P>0.05), without effect of method (P<0.05). Considering the four methods studied, the mean rates of protein synthesis and breakdown was, respectively, 19% and 21% lower in old than adult dogs (P<0.05). No age effect was observed for nutrient digestibility and nitrogen balance (P>0.05). These results support the hypothesis that metabolic alterations are involved on sarcopenia development in old dogs. On the third study a diet effect was observed: both in adult and old dogs fed the supplemented food higher protein flow was observed than for animals fed the control diet (P>0.05). Although statistically similar, this increase in protein flow was 42% higher for adult than for old dogs. In addition, at the end of the period of diet intake a tendency for higher lean body mass was observed for old dogs fed the supplemented food in comparison to control (P=0.06). As conclusion, the four methods evaluated was adequate with similar results of protein synthesis and degradation. A diet supplementation with DHA, arginine and BCA increased the protein flow rate, possibly reducing sarcopenia development, deserving future studies. (AU) | |
| FAPESP's process: | 19/00790-8 - Methods to study protein turnover in adult and aging dogs |
| Grantee: | Letícia Graziele Pacheco |
| Support Opportunities: | Scholarships in Brazil - Doctorate |