Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching
The causes of embryonic mortality in Hermann’s tortoises (<i>Testudo hermanni</i>) during artificial incubation were determined. Total egg failure at the end of the hatching period was investigated. The hatching artefacts represented 19.2% (N = 3557) of all eggs (N = 18,520). The viabili...
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| Format: | Article |
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MDPI AG
2021-02-01
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| Series: | Animals |
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| Online Access: | https://www.mdpi.com/2076-2615/11/2/478 |
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| author | Alenka Dovč Mateja Stvarnik Renata Lindtner Knific Gordana Gregurić Gračner Igor Klobučar Olga Zorman Rojs |
| author_facet | Alenka Dovč Mateja Stvarnik Renata Lindtner Knific Gordana Gregurić Gračner Igor Klobučar Olga Zorman Rojs |
| author_sort | Alenka Dovč |
| collection | DOAJ |
| description | The causes of embryonic mortality in Hermann’s tortoises (<i>Testudo hermanni</i>) during artificial incubation were determined. Total egg failure at the end of the hatching period was investigated. The hatching artefacts represented 19.2% (N = 3557) of all eggs (N = 18,520). The viability rate of incubated eggs was 80.8%. The eggs, i.e., embryos, were sorted according to the cause of unsuccessful hatching and subsequently analyzed. Some of the eggs were divided into two or more groups. Unfertilized eggs were confirmed in 61.0%, infected eggs in 52.5%, and eggs in various stages of desiccation in 19.1%. This group also included mummified embryos. <i>Pseudomonas aeruginosa</i>, <i>Bacillus</i> sp., <i>Purpureocillium lilacinum</i>, and <i>Escherichia coli</i> were frequently confirmed in infected eggs. Embryos were divided into three groups: embryos up to 1.0 cm—group 1 (2.2%), embryos from 1.0 cm to 1.5 cm—group 2 (5.4%) and embryos longer than 1.5 cm—group 3 (7.3%) of all unhatched eggs. Inability of embryos to peck the shell was found in 1.3%. These tortoises died shortly before hatching. Embryos still alive from the group 2 and group 3 were confirmed in 0.7% of cases. Dead and alive deformed embryos and twins were detected in the group 3 in 0.5% and 0.1% of cases, respectively. For successful artificial hatching, it is important to establish fumigation with disinfectants prior to incubation and elimination of eggs with different shapes, eggs with broken shells, and eggs weighted under 10 g. Eggs should be candled before and periodically during artificial incubation, and all unfertilized and dead embryos must be removed. Heartbeat monitor is recommended. Proper temperature and humidity, incubation of “clean” eggs on sterile substrate and control for the presence of mites is essential. Monitoring of the parent tortoises is also necessary. |
| first_indexed | 2024-03-09T00:58:15Z |
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| institution | Directory Open Access Journal |
| issn | 2076-2615 |
| language | English |
| last_indexed | 2024-03-09T00:58:15Z |
| publishDate | 2021-02-01 |
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| spelling | doaj.art-0f2f1acd11d64d918bfd37d8272437e62023-12-11T16:45:42ZengMDPI AGAnimals2076-26152021-02-0111247810.3390/ani11020478Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in HatchingAlenka Dovč0Mateja Stvarnik1Renata Lindtner Knific2Gordana Gregurić Gračner3Igor Klobučar4Olga Zorman Rojs5Institute for Poultry, Birds, Small Animals and Reptiles, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, SloveniaClinic for Reproduction and Large Animals, Veterinary Faculty, Gerbičeva 60, 1000 Ljubljana, SloveniaInstitute for Poultry, Birds, Small Animals and Reptiles, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, SloveniaDepartment of Animal Hygiene, Behaviour and Welfare, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, CroatiaClinic for Reproduction and Large Animals, Veterinary Faculty, Gerbičeva 60, 1000 Ljubljana, SloveniaInstitute for Poultry, Birds, Small Animals and Reptiles, Veterinary Faculty, University of Ljubljana, Gerbičeva 60, 1000 Ljubljana, SloveniaThe causes of embryonic mortality in Hermann’s tortoises (<i>Testudo hermanni</i>) during artificial incubation were determined. Total egg failure at the end of the hatching period was investigated. The hatching artefacts represented 19.2% (N = 3557) of all eggs (N = 18,520). The viability rate of incubated eggs was 80.8%. The eggs, i.e., embryos, were sorted according to the cause of unsuccessful hatching and subsequently analyzed. Some of the eggs were divided into two or more groups. Unfertilized eggs were confirmed in 61.0%, infected eggs in 52.5%, and eggs in various stages of desiccation in 19.1%. This group also included mummified embryos. <i>Pseudomonas aeruginosa</i>, <i>Bacillus</i> sp., <i>Purpureocillium lilacinum</i>, and <i>Escherichia coli</i> were frequently confirmed in infected eggs. Embryos were divided into three groups: embryos up to 1.0 cm—group 1 (2.2%), embryos from 1.0 cm to 1.5 cm—group 2 (5.4%) and embryos longer than 1.5 cm—group 3 (7.3%) of all unhatched eggs. Inability of embryos to peck the shell was found in 1.3%. These tortoises died shortly before hatching. Embryos still alive from the group 2 and group 3 were confirmed in 0.7% of cases. Dead and alive deformed embryos and twins were detected in the group 3 in 0.5% and 0.1% of cases, respectively. For successful artificial hatching, it is important to establish fumigation with disinfectants prior to incubation and elimination of eggs with different shapes, eggs with broken shells, and eggs weighted under 10 g. Eggs should be candled before and periodically during artificial incubation, and all unfertilized and dead embryos must be removed. Heartbeat monitor is recommended. Proper temperature and humidity, incubation of “clean” eggs on sterile substrate and control for the presence of mites is essential. Monitoring of the parent tortoises is also necessary.https://www.mdpi.com/2076-2615/11/2/478<i>Testudo hermanni</i>eggsartificial incubationhatching artefacts |
| spellingShingle | Alenka Dovč Mateja Stvarnik Renata Lindtner Knific Gordana Gregurić Gračner Igor Klobučar Olga Zorman Rojs Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching Animals <i>Testudo hermanni</i> eggs artificial incubation hatching artefacts |
| title | Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching |
| title_full | Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching |
| title_fullStr | Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching |
| title_full_unstemmed | Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching |
| title_short | Monitoring of Unhatched Eggs in Hermann’s Tortoise (<i>Testudo hermanni</i>) after Artificial Incubation and Possible Improvements in Hatching |
| title_sort | monitoring of unhatched eggs in hermann s tortoise i testudo hermanni i after artificial incubation and possible improvements in hatching |
| topic | <i>Testudo hermanni</i> eggs artificial incubation hatching artefacts |
| url | https://www.mdpi.com/2076-2615/11/2/478 |
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