Reproductive Traits of an Invasive Alien Population of Grey Squirrel (Sciurus carolinensis) in Central Italy
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Animal Capture and Sample Collection
2.2. Morphometric Evaluation of the Female Genital System and Uterine Scar Analysis
2.3. Morphometric Evaluation of the Testicles
2.4. Statistical Analysis
3. Results
3.1. Morphometric Evaluation of the Female Genital System
3.2. Uterine Scar Analysis
3.3. Morphometric and Histological Evaluation of the Testicles
4. Discussion
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Reproductive Phase | Body Weight (g) | Ovary Status | Ovary Weight (mg) | Ovary Length (cm) | Ovary Width (cm) | Uterus Appearance | Uterus Weight (g) | Uterine Scar | Uterine Horn Length (cm) | Uterine Horn Width (cm) | Uterine Body Length (cm) | Uterine Body Width (cm) |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Immature | 438.01 a ± 43.24 | No graafian follicle | 0.24 a ± 0.21 | 0.37 a ± 0.10 | 0.24 a,b ± 0.06 | Small, ribbon-like | 0.22 a ± 0.08 | No | 6.4 a ± 1.8 | 0.20 a ± 0.4 | 0.76 a,b,c ± 0.31 | 0.41 a,b,c ± 0.18 |
Follicular | 521.54 a,b ± 55.5 | Graafian follicle | 0.23 a ± 0.04 | 0.38 a ± 0.06 | 0.27 a,b ± 0.05 | Round, oedematous, tonic in the oestrous phase | 0.82 a ± 0.49 | Yes/No | 9.6 b ± 3.1 | 0.35 b ± 0.11 | 1.01 a,b,c ± 0.38 | 0.64 a,b,c ± 0.16 |
Luteal | 562.99 b ± 19.49 | Corpus luteum | 0.64 a ± 0.48 | 0.49 a ± 0.19 | 0.36 b.c ± 0.19 | Round, oedematous, tonic | 2.08 b ± 0.53 | Yes/No | 13.3 c ± 2.8 | 0.46 c ± 0.08 | 1.24 a,b,c ± 0.29 | 0.76 b ± 0.15 |
Pregnant | 550.02 b ± 11.55 | Corpus luteum in the first period | 0.21 a ± 0.05 | 0.42 a ± 0.06 | 0.32 b,c ± 0.03 | Round, oedematous, tonic, with embryonic vesicles/embryos/foetuses | 3.28 b ± 1.05 | No | 15.5 c ± 3.9 | 0.51 c ± 0.13 | 1.45 b ± 0.33 | 0.98 b ± 0.40 |
Anoestrous | 495.38 a,b ± 57.99 | No graafian follicle | 0.33 a ± 0.20 | 0.39 a ± 0.07 | 0.26 a,b ± 0.05 | Small, ribbon-like | 0.57 a ± 0.30 | Yes/No | 9.4 b ± 2.2 | 0.34 b ± 0.08 | 0.96 c ± 0.26 | 0.56 c ± 0.09 |
Reproductive Phase | ||||||
---|---|---|---|---|---|---|
Catch period | Immature | Follicular | Luteal | Pregnant | Anoestrus | Total |
Winter 15/12–15/03 | 1 | 4 | 6 | 7 | 4 | 21 |
Spring 15/03–15/06 | 1 | 9 | 6 | 2 | 6 | 24 |
Summer 15/06–15/09 | 1 | - | - | 1 | - | 2 |
Autumn 15/09–15/12 | 2 | - | - | - | 14 | 16 |
Total | 5 (7.81%) | 13 (20.31%) | 12 (18.75%) | 10 (15.65%) | 24 (37.5%) | 63 |
Litter Presence | No. of Females | Litter Size | ||
---|---|---|---|---|
None | 14 (31%) | Period | Number of scars/female | Uterine scars range |
One | 17 (38%) | 15/12–15/03 | 3.55 ± 1.88 * | 1−7 |
Two | 14 (31%) | 16/03–15/06 | 2.14 ± 1.46 | 2−6 |
Total | 45 | Annual | 4.52 ± 1.88 | 1−7 |
Reproductive Phase | Body Weight (gr) | Testicle Weight (gr) | Testicle Length (cm) | Testicle Width (cm) | Epididymis Weight (gr) | ST Diameter (µm) | Testicle Position | Germinative Epithelium Morphotype | SG |
---|---|---|---|---|---|---|---|---|---|
Immature | 399.25 a ± 70.11 | 0.10 a ± 0.03 | 0.84 a ± 0.23 | 0.44 a ± 0.15 | 0.19 a ± 0.16 | 79.93 a ± 18.70 | ABD | Mp1 | No |
Pubertal | 460.18 a,b ± 43.67 | 0.69 b ± 0.29 | 1.82 b ± 0.18 | 0.88 b ± 0.17 | 0.85 b ± 0.60 | 151.49 b ± 20.05 | SCR | Mp2 | No |
Spermatogenesis | 502.31 b ± 46.37 | 2.52 c ± 0.26 | 2.00 b ± 0.46 | 1.34 c ± 0.46 | 2.01 c ± 0.62 | 241.18 c ± 26.38 | SCR | Mp3 | Yes |
Regression | 515.40 b ± 36.11 | 1.85 d ± 0.17 | 2.01 b ± 0.22 | 1.11 b,c ± 0.16 | 0.36 a,b ± 0.22 | 166.52 b ± 55.35 | SCR | Mp4 | No |
Reproductive Phase | |||||
---|---|---|---|---|---|
Immature | Pubertal | Spermatogenesis | Regression | Total N | |
Winter 15/12–15/03 | 4 | 9 | 10 | 3 | 26 |
Spring 15/03–15/06 | 5 | 1 | 6 | ||
Summer 15/06–15/09 | 5 | 2 | 7 | ||
Autumn 15/09–15/12 | 7 | 2 | 2 | 1 | 12 |
Total | 16 (31.37%) | 11 (21.57%) | 19 (37.26%) | 5 (9.80%) | 51 |
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Maranesi, M.; Bufalari, A.; Dall’Aglio, C.; Paoloni, D.; Moretti, G.; Crotti, S.; Manuali, E.; Stazi, M.; Bergamasco, F.; Cruciani, D.; et al. Reproductive Traits of an Invasive Alien Population of Grey Squirrel (Sciurus carolinensis) in Central Italy. Animals 2020, 10, 738. https://doi.org/10.3390/ani10040738
Maranesi M, Bufalari A, Dall’Aglio C, Paoloni D, Moretti G, Crotti S, Manuali E, Stazi M, Bergamasco F, Cruciani D, et al. Reproductive Traits of an Invasive Alien Population of Grey Squirrel (Sciurus carolinensis) in Central Italy. Animals. 2020; 10(4):738. https://doi.org/10.3390/ani10040738
Chicago/Turabian StyleMaranesi, Margherita, Antonello Bufalari, Cecilia Dall’Aglio, Daniele Paoloni, Giulia Moretti, Silvia Crotti, Elisabetta Manuali, Marica Stazi, Francesca Bergamasco, Deborah Cruciani, and et al. 2020. "Reproductive Traits of an Invasive Alien Population of Grey Squirrel (Sciurus carolinensis) in Central Italy" Animals 10, no. 4: 738. https://doi.org/10.3390/ani10040738
APA StyleMaranesi, M., Bufalari, A., Dall’Aglio, C., Paoloni, D., Moretti, G., Crotti, S., Manuali, E., Stazi, M., Bergamasco, F., Cruciani, D., Di Meo, A., Boiti, C., Zerani, M., & Mercati, F. (2020). Reproductive Traits of an Invasive Alien Population of Grey Squirrel (Sciurus carolinensis) in Central Italy. Animals, 10(4), 738. https://doi.org/10.3390/ani10040738