Digestive Enzymes in two Species of Marine Cinclodes (Passeriformes: Furnariidae)

AbstractChanges in digestive enzyme activity along the intestine may be related to changes in substrate concentration in the intestine. We examined the distribution of digestive enzymes along the intestine in two species of carnivorous passerine birds from the genus Cinclodes. Both species lacked sucrase activity, suggesting that these species are unable to feed on sucrose-rich diets. Distribution of maltase and aminopeptidase-N activity differed from that found in other passerines, including omnivorous species, but resembled those found in herbivorous and frugivorous birds. We hypothesize that the type of prey items that Cinclodes consume may explain the pattern of maltase and aminopeptidase-N expression.Enzimas Digestivas en Dos Especies de Cinclodes Marinos (Passeriformes: Furnariidae)Resumen. Los cambios en los niveles de actividad enzimática digestiva a lo largo del intestino de aves pueden estar relacionados con cambios en la concentración de substratos en el intestino. En este estudio examinamos la distribución de enzimas digestivas a lo largo del intestino en dos especies de aves paseriformes del género Cinclodes. Ambas especies carecen de actividad de sacarasa lo que sugiere que estas especies son incapaces de consumir dietas ricas en sacarosa. La distribución de la actividad de maltasa y aminopeptidasa-N difiere de la documentada para otros paseriformes, incluyendo especies omnívoras, y es similar a la encontrada en aves herbívoras y frugívoras. Se sugiere que el tipo de presas consumidas por Cinclodes explicaría el patrón de expresión de maltasa y aminopeptidasa-N.

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Composition of gastrointestinal content, protease and lipase activities in summer and winter of four freshwater siluriforms (Teleostei: Actinopterygii) with two different feeding habits

Zoologia (Curitiba) ◽

10.3897/zoologia.35.e13286 ◽

2018 ◽

Vol 35 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Ana Paula Gottlieb Almeida ◽

Everton Luis Zardo ◽

Candida Toni ◽

Everton Rodolfo Behr ◽

Leila Picolli da Silva ◽

...

Keyword(s):

Enzyme Activity ◽

Gastrointestinal Tract ◽

Nutrient Availability ◽

Enzyme Activities ◽

Digestive Enzymes ◽

Feeding Habits ◽

Digestive Enzyme ◽

Digestive Enzyme Activity ◽

The Relationship ◽

Over Time

The aim of this study was to determine the composition of gastrointestinal content and protease and lipase activities in summer and winter as well as to evaluate the relationship between digestive enzyme activity and centesimal composition of gastrointestinal content and feeding habits of two omnivorous species, Rhamdiaquelen (Quoy & Gaimard, 1824) and Pimelodusmaculatus (LaCèpede, 1803), and of two detritivorous species, Loricariichthysanus (Valenciennes, 1835) and Hypostomuscommersoni (Valenciennes, 1836). The activities of pepsin, trypsin, chymotrypsin, and lipase, and the levels of proteins and lipids in the gastrointestinal tract, were evaluated. The enzyme activities were not related to the centesimal composition of gastrointestinal content or feeding habits. This finding could be associated with the variations of nutrient availability over time in the environment, as was observed in the centesimal composition of food ingested by the fish in summer and winter. The analyzed enzymes exhibited a constitutive character in these species; that is, the digestive enzymes are always available in the gastrointestinal tract to digest any food that the fish may find as an adaptation to better utilize the nutrients available in the environment in winter and summer.

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Interplay among energy metabolism, organ mass and digestive enzyme activity in the mouse-opossum Thylamys elegans: the role of thermal acclimation

Journal of Experimental Biology ◽

10.1242/jeb.205.17.2697 ◽

2002 ◽

Vol 205 (17) ◽

pp. 2697-2703 ◽

Cited By ~ 4

Author(s):

Roberto F. Nespolo ◽

Leonardo D. Bacigalupe ◽

Pablo Sabat ◽

Francisco Bozinovic

Keyword(s):

Enzyme Activity ◽

Energy Metabolism ◽

Metabolic Rate ◽

Digestive Enzyme ◽

Thermal Acclimation ◽

Aminopeptidase N ◽

Digestive Enzyme Activity ◽

Organ Mass ◽

Significant Difference

SUMMARY The potential for thermal acclimation in marsupials is controversial. Initial studies suggest that the thermoregulatory maximum metabolic rate (MMR)in metatherians cannot be changed by thermal acclimation. Nevertheless, recent studies reported conspicuous seasonality in both MMR and in basal metabolic rate (BMR). We studied the role of thermal acclimation in the Chilean mouse-opossum, Thylamys elegans, by measuring MMR and BMR before and after acclimation to cold or warm conditions. Following acclimation we also measured the mass of metabolically active organs, and the activity of a key digestive enzyme, aminopeptidase-N. No significant effect of thermal acclimation (i.e. between cold- and warm-acclimated animals) was observed for body mass, MMR, body temperature or factorial aerobic scope. However, the BMR of cold-acclimated animals was 30 % higher than for warm-acclimated individuals. For organ mass, acclimation had a significant effect on the dry mass of caecum, liver and kidneys only. Stepwise multiple regression using pooled data showed that 71 % of the variation in BMR is explained by the digestive organs. Overall, these results suggest that MMR is a rather rigid variable, while BMR shows plasticity. It seems that T. elegans cannot respond to thermal acclimation by adjusting its processes of energy expenditure (i.e. thermogenic capacity and mass of metabolically active organs). The lack of any significant difference in aminopeptidase-N specific activity between warm- and cold-acclimated animals suggests that this response is mainly quantitative (i.e. cell proliferation) rather than qualitative (i.e. differential enzyme expression). Finally, as far as we know, this study is the first to report the effects of thermal acclimation on energy metabolism, organ mass and digestive enzyme activity in a marsupial.

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