Gastric function in Caiman crocodilus (Crocodylia: Reptilia)—I. Rate of gastric digestion and gastric motility as a function of temperature

Abstract

A cannulation method was devised that allows continuous safe gastric sampling and recording of intragastric pressure in Caiman crocodilus.2. In C. crocodilus, fed 5 per cent of the body weight, complete gastric emptying takes an average of 99 (+_ 10) hr at 30°C, to an average of 315 (4-16) hr at 15°C.3. Two types of gastric contractions were recorded in C. crocodilus, by means of intragastric pressure measurements, at 20, 25 and 30°C.4. The two types of contractions were recorded regardless of the feeding state of the animals. 5. Their frequency and amplitude increase with temperature or upon feeding.

The Right‐to‐Left Shunt of Crocodilians Serves Digestion

“…We found that in American alligators, preferred T b was significantly greater and less variable after feeding than when fasting. Although our results differ from those in prior research, which found no change in preferred body temperature with feeding in a crocodilian (Diefenbach 1975a(Diefenbach , 1975b, in the former study, the animals were handled daily to introduce them to the thermal gradient. If the animals were unaccustomed to this handling, it could have altered their behavior and may explain the discrepancy between the studies.…”

The Right‐to‐Left Shunt of Crocodilians Serves Digestion

“…We found that in American alligators, preferred T b was significantly greater and less variable after feeding than when fasting. Although our results differ from those in prior research, which found no change in preferred body temperature with feeding in a crocodilian (Diefenbach 1975a(Diefenbach , 1975b, in the former study, the animals were handled daily to introduce them to the thermal gradient. If the animals were unaccustomed to this handling, it could have altered their behavior and may explain the discrepancy between the studies.…”

Digestion versus abrasion features in rodent bones

“…D). These results confirm observations by Diefenbach () and Fisher () about the effects of crocodile digestion, where gastric juices are almost exclusively HCl with extremely reduced enzyme activity. As a result, the digested bones displayed mild rounding but heavy decalcification, to the point that they are almost reduced to its organic matrix (Andrews & Fernández‐Jalvo ).…”

Integrating physiology into conservation: an approach to help guide translocations of a rare reptile in a warming environment

“…Prey‐catching and prey‐handling times were maintained at a relatively similar level between 20 and 12 °C by all species excluding skinks, but showed a large decrease in performance at 5 °C. The increased gut‐passage time observed at cool temperatures was also expected, given previous studies demonstrating reduced gastro‐intestinal motility, secretion and absorption at low temperatures in other reptiles (Licht, 1964; Diefenbach, 1975). Notably, digestion of mealworms by tuatara was not completed at 12 °C within the timeframe of the trial (5–6 weeks), although faeces containing digested mealworms were produced two to three days after tuatara had access to a heat source.…”

The Right‐to‐Left Shunt of Crocodilians Serves Digestion

“…We found that in American alligators, preferred T b was significantly greater and less variable after feeding than when fasting. Although our results differ from those in prior research, which found no change in preferred body temperature with feeding in a crocodilian (Diefenbach 1975a(Diefenbach , 1975b, in the former study, the animals were handled daily to introduce them to the thermal gradient. If the animals were unaccustomed to this handling, it could have altered their behavior and may explain the discrepancy between the studies.…”

Digestion versus abrasion features in rodent bones

“…D). These results confirm observations by Diefenbach () and Fisher () about the effects of crocodile digestion, where gastric juices are almost exclusively HCl with extremely reduced enzyme activity. As a result, the digested bones displayed mild rounding but heavy decalcification, to the point that they are almost reduced to its organic matrix (Andrews & Fernández‐Jalvo ).…”

Integrating physiology into conservation: an approach to help guide translocations of a rare reptile in a warming environment

“…Prey‐catching and prey‐handling times were maintained at a relatively similar level between 20 and 12 °C by all species excluding skinks, but showed a large decrease in performance at 5 °C. The increased gut‐passage time observed at cool temperatures was also expected, given previous studies demonstrating reduced gastro‐intestinal motility, secretion and absorption at low temperatures in other reptiles (Licht, 1964; Diefenbach, 1975). Notably, digestion of mealworms by tuatara was not completed at 12 °C within the timeframe of the trial (5–6 weeks), although faeces containing digested mealworms were produced two to three days after tuatara had access to a heat source.…”

The Right‐to‐Left Shunt of Crocodilians Serves Digestion

“…We found that in American alligators, preferred T b was significantly greater and less variable after feeding than when fasting. Although our results differ from those in prior research, which found no change in preferred body temperature with feeding in a crocodilian (Diefenbach 1975a(Diefenbach , 1975b, in the former study, the animals were handled daily to introduce them to the thermal gradient. If the animals were unaccustomed to this handling, it could have altered their behavior and may explain the discrepancy between the studies.…”

Digestion versus abrasion features in rodent bones

“…D). These results confirm observations by Diefenbach () and Fisher () about the effects of crocodile digestion, where gastric juices are almost exclusively HCl with extremely reduced enzyme activity. As a result, the digested bones displayed mild rounding but heavy decalcification, to the point that they are almost reduced to its organic matrix (Andrews & Fernández‐Jalvo ).…”

Integrating physiology into conservation: an approach to help guide translocations of a rare reptile in a warming environment

“…Prey‐catching and prey‐handling times were maintained at a relatively similar level between 20 and 12 °C by all species excluding skinks, but showed a large decrease in performance at 5 °C. The increased gut‐passage time observed at cool temperatures was also expected, given previous studies demonstrating reduced gastro‐intestinal motility, secretion and absorption at low temperatures in other reptiles (Licht, 1964; Diefenbach, 1975). Notably, digestion of mealworms by tuatara was not completed at 12 °C within the timeframe of the trial (5–6 weeks), although faeces containing digested mealworms were produced two to three days after tuatara had access to a heat source.…”