A parthenogenetic Varanus.

Amphibia-Reptilia 26(4):507-514. DOI:10.1163/156853805774806296.

Abstract:

We report on a case of parthenogenesis in the varanid lizard Varanus panoptes. Parthenogenesis was observed in a female kept alone for three years. A clutch was deposited from which a single egg could be secured and incubated. Incubation was successful and a male specimen hatched. Obviously the newborn was produced without contribution of a father. After the unisexual reproduction, the mother was kept with males and bisexual reproduction was observed, too. We performed DNA Fingerprinting and showed that the parthenogen and its mother exhibit almost identical DNA patterns. The bisexually produced offspring has only a subset of bands in common with the mother and another subset in common with the father. Thus DNA Fingerprinting is in accordance with our observations and confims parthenogenesis.We compare our results with existing cytological models of parthenogenesis and point out the following: 1. The mode of parthenogenesis described here is facultative, as the mother was able to reproduce in the bisexual mode as well. 2. The parthenogen is male and hence not a clone of the mother. 3. Almost complete heredity of maternal Fingerprint markers. All these points considered our case seem to fit to no known model of parthenogenesis exactly. But an additional recombination could result homogamety (would explain the sex of the parthenogen) while expressing almost all maternal bands.

lenk-biblio

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Spawning behavior of garden eels, Gorgasia preclara and Heteroconger hassi (Heterocongrinae), observed in captivity.

Marine Behaviour and Physiology 48(5). DOI:10.1080/10236244.2015.1064213

Zusammenfassung:

The behavior and reproductive ecology of typically nocturnal marine eels is poorly known but garden eels (Congridae, Heterocongrinae) are familiar tropical marine eels. They live in colonies and protrude their bodies from burrows during the daytime to feed on zooplankton. Apparent daytime courtship/spawning-like behavior has been observed within the colonies but actual spawning and fertilized egg production has not been confirmed. This study describes observations of splendid garden eels (Gorgasia preclara) and spotted garden eels (Heteroconger hassi) spawning in low light at night and producing fertilized eggs in a large multispecies public-display tank in the Sumida Aquarium. Video recordings of 5 of 17 detected spawning or egg or sperm release events documented the spawning behavior of G. preclara, and positively buoyant fertilized eggs of both species were collected. Their spawning behavior while protruding from widely spaced burrows confirms that garden eels likely spawn within their colonies with their pelagic eggs drifting away with currents.

kakizaki-biblio

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Haltung und Vermehrung des Kleinen Armmolchs Siren intermedia mit Berichten zum Fortpflanzungs- und Brutpflegeverhalten.

amphibia 14(1): 16-24

Volltext

reinhard-biblio

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Goliath frogs build nests for spawning – the reason for their gigantism?

Journal of Natural History  53(21-22): 1263-1276.
doi:org/10.1080/00222933.2019.1642528

Abstract:

In contrast to its popularity, astonishingly few facts have become known about the biology of the Goliath Frog, Conraua goliath. We herein report the so far unknown construction of nests as spawning sites by this species. On the Mpoula River, Littoral District, West Cameroon we identified 19 nests along a 400 m section. Nests could be classified into three types. Type 1 constitutes rock pools that were cleared by the frogs from detritus and leaf-litter; type 2 constitutes existing washouts at the riverbanks that were cleared from leaf-litter and/or expanded, and type 3 were depressions dug by the frogs into gravel riverbanks. The cleaning and digging activities of the frogs included removal of small to larger items, ranging from sand and leaves to larger stones. In all nest types eggs and tadpoles of C. goliath were detected. All nest types were used for egg deposition several times, and could comprise up to three distinct cohorts of tadpoles. Nests seemed to be clustered. Camera trapping revealed that nests are guarded by adult frogs at night. The breeding nests may allow the frogs to deposit their eggs away from the torrent rivers, and potential egg and tadpole predators. As nest construction, at least in some cases, requires the removal of large and heavy items, we hypothesize that this can only be achieved by decent sized frogs, possibly explaining the unique size of the species.

schäfer-biblio

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The reproductive behaviour of the suni Neotragus moschatus zuluensis in captivity.

Koedoe 39 (1) 123-126.

Volltext (PDF)

pretorius-biblio

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Montag, 09 November 2020 11:47

LANDOWSKI, J. (1961)

Breeding the Pine Marten (Martes martes L. 1758) in captivity.

International Zoo Yearbook 3: 21-23.

https://doi.org/10.1111/j.1748-1090.1962.tb03376.x

Inhalt:

Seit 1949 hat der Warschauer Zoo intensiv über den Baummarder geforscht, um Kenntnisse über die Fortpflanzungspyhsiologie zu gewinnen und Methoden für eine erfolgreiche Haltung und Zucht zu erarbeien. Am 28.03.1953 kam es zur ersten Geburt und danach wurden bis 1961 zehn weitere Würfe großgezogen.

landowski-biblio

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Donnerstag, 06 August 2020 13:14

CSAR, D., SCHAUER, M. & GUMPINGER, C. (2012)

Long-term investigation on fish migration patterns between pre-alpine lakes and their major tributaries with special focus on protected species within SAC areas.

Conference Paper 9th ISE 2012, Vienna. (PDF)

Abstract:

In the designated SAC (Special Area of Conservation) site“Mond-und Attersee” (comprising two large pre-alpine lakes in Upper Austria and the mouths of their major tributaries) the spawning migration of the protected species pearlfish (Rutilus meidingeri) and Danube bleak (Alburnus mento) was investigated in the years 2004 and 2010. For this purpose, a dynamic fishweir with an integrated trap for catching upstream migrating fish was installed near the mouths of the respective rivers. The main factor correlating with the spawning migration turned out to be the water temperature of the rivers. Furthermore, differences between sexes were found concerning body length and weight as well as the main immigration period into the streams.

csar-biblio

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Maintenance and breeding of duikers Cephalophus spp. at Gladys Porter Zoo, Brownsville.

International Zoo Yearb. 20: 93-98.
https://doi.org/10.1111/j.1748-1090.1980.tb00949.x

Inhalt:

Der Gladys Porter Zoo hielt damals eine der größten Ducker-Kollektionen bestehend aus 30 Tieren in 6 Arten (C. jentinki, C. Sylvicultor, C. niger, D. dorsalis, C. zebra und P. maxwelli). Es wird über die Haltung und Zucht dieser Tiere berichtet, insbesondere über den erhöhten Kupferbedarf des Zebraduckers.

farst-biblio

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Donnerstag, 18 Juni 2020 08:36

UDELL, C. C. (1981)

Breeding the Zebra Cephalophus zebra duiker at the Los Angeles Zoo.

International Zoo Yearb. 21: 155-158.
https://doi.org/10.1111/j.1748-1090.1981.tb01972.x

Inhalt:

Es wird über die Haltung, Fütterung und Zucht von Zebraduckern im Los angeles Zoo berichtet sowie von einem Versuch, die Tiere mit Zwergmeerkatzen zu vergesellschaften, der daran scheiterte, dass die Meerkatzen nach einigen Monaten beganndne, den ducker-Bock anzugreifen.

udell-biblio

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Donnerstag, 18 Juni 2020 08:05

SCHWEERS, S. (1972)

Zur Fortpflanzungsbiologie des Zebraduckers Cephalophus zebra (Gray,1838) im Vergleich zu anderen Cephalophus-Arten.

Zeitschrift für Säugetierkunde 38: 303-313.

Zusammenfassung:

Die Ergebnisse zur Fortpflanzungsbiologie des Zebraduckers nach einer zehnmonatigen Untersuchung im Rahmen einer Staatsexamensarbeit werden dargestellt und mit bisher Bekanntem anderer Cephalophus-Arten verglichen. Dabei wurde ein Postpartum-Ostrus zehn Tage nach einer vorausgegangenen Geburt wahrscheinlich. Das Paarungsverhalten wurde beschrieben sowie Veränderungen des Weibchens während der Trächtigkeit. Es wurde eine Tragzeit von 221-229 Tagen festgestellt. Weiterhin wurden zwei Geburten von C. zebra skizziert, die Eltern-Kind-Beziehungen untersucht sowie die Jungtierentwicklung detailliert beschrieben: Gewichtsentwicklung, Reifung des Körpers, Reifung von Verhaltensweisen, Entwicklungsphasen der Nahrungsaufnahme, Abliegeperiode, Neugier-und Spielverhalten.

schweers-biblio

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