Reproductive characteristics of wild native Australian Rattus (Rodentia : Muridae)

1973 ◽  
Vol 21 (4) ◽  
pp. 437 ◽  
Author(s):  
JM Taylor ◽  
BE Horner
Keyword(s):  
Sexual Maturity ◽  
Reproductive Potential ◽  
Field Conditions ◽  
Museum Specimens ◽  
Seasonal Breeding ◽  
Reproductive Characteristics ◽  
Accessory Sex Glands

Reproduction in field populations of the five species and 13 of 14 subspecies of native Australian Rattus is compared, using both materials personally collected and museum specimens. We have separated each subspecies into juvenile and adult categories, the dividing point reflecting the approximate size at which sexual maturity is reached. Occurrence of pregnancies and juveniles, treated monthly, permit estimates of time and length of seasonal breeding for each subspecies. Information on gonads and accessory sex glands is given for both breeding and non-breeding adults and for juveniles. All Australian subspecies of Rattus have a fundamentally similar mechanism of reproduction. Those attaining high densities have the highest ovulation rates, the largest litter sizes, and the greatest number of teats. Furthermore, in the two subspecies of high reproductive potential for which we have evidence, females can be precocious in attaining sexual maturity under field conditions.

scholarly journals Growth and reproduction properties of endemic Capoeta kosswigi and Barbus ercisianus in the Deliçay Stream (Van, Turkey)

2021 ◽  
Vol 38 (3) ◽  
pp. 293-302
Author(s):  
Ataman Altuğ Atıcı ◽  
Ahmet Sepil ◽  
Fazıl Şen ◽  
Asude Çavuş
Keyword(s):  
Sexual Maturity ◽  
Condition Factor ◽  
Fork Length ◽  
Lake Van ◽  
Reproductive Characteristics ◽  
Lake Van Basin ◽  
Growth And Reproduction

In this study, the growth and reproductive characteristics of Capoeta kosswigi Karaman, 1969 and Barbus ercisianus Karaman, 1971, which are endemic to the Lake Van Basin, in Deliçay (Van) were investigated. A total of 309 C. kosswigi and 288 B. ercisianus specimens were caught by electrofishing between April and August 2018. The fork length of C. kosswigi and B. ercisianus ranged from 3.7-26.1 cm and from 4.3-22.7 cm, and the total weights ranged from 0.6-227.4 g and from 1.2-140.0 g, respectively. The most intensive catching was in C. kosswigi population of 5.0-6.9 (27.5%) cm and 0-19.9 (67.0%) g in the groups, and 12.0-13.9 (24.7%) cm and 0-9.9 (23.3%) g groups in B. ercisianus. Condition factor was determined as 1.305±0.008 (0.798-1.886) in C. kosswigi and 1.158±0.006 (0.864-1.559) in B. ercisianus. The length-weight relationships were calculated as W = 0.01435 × L2.952 (r2 = 0.996) for C. kosswigi and W = 0.01276 × L2.959 (r2 = 0.994) for B. ercisianus. The M:F ratio was calculated as 1:0.15 in C. kosswigi and 1:0.64 in B. ercisianus. It was established that C. kosswigi attained sexual maturity when they reached to 11 cm fork length for males, 18 cm fork length for females. Maturation of B.ercisianus individuals occurred at 9 cm fork length in males and 12 cm fork length in females. The spawning in C. kosswigi was observed from 1st week of May to 2nd week of July, and in B. ercisianus from 1st week of May to 1st week of August. It may be suggested that minimum catching size must be 20 cm fork length for C. kosswigi and 15 cm fork length for B. ercisianus.

186 QUANTITATIVE ECHOGENICITY AND ECHOTEXTURE ANALYSIS OF THE ACCESSORY SEX GLANDS OF PUBERTAL AND MATURE DORPER RAMS

2016 ◽  
Vol 28 (2) ◽  
pp. 224
Author(s):  
E. S. C. Camela ◽  
R. P. Nociti ◽  
V. J. C. Santos ◽  
B. I. Macente ◽  
G. S. Maciel ◽  
...  
Keyword(s):  
Image Analysis ◽  
Sexual Maturity ◽  
Calculated Data ◽  
Tukey Test ◽  
Statistical Procedures ◽  
Accessory Sex Glands ◽  
Linear Transducer ◽  
Computerised Image Analysis ◽  
Levene Test ◽  
Transducer Frequency

This study aimed to analyse the ultrasonographic attributes of vesicular, prostate, and bulbourethral glands in pubertal and mature Dorper rams. Forty-five rams were used in the same day (pubertal: 8–11 months, n = 24; mature: ≥12 months, n = 21). The B-mode ultrasounds examinations were performed using MyLab 30Vet equipment (Esaote, Naples, Italy) connected to transrectal linear transducer (frequency of 7.5 MHz). The echogenicity [(mean numerical pixel values (NPV)] and pixel heterogeneity (standard deviation of NPV) of accessory sex glands parenchymas was determined by computerised image analysis using Image ProPlus® software (Media Cybernetics Inc., Rockville, MD, USA). For the pairs organs a mean for each parameter were calculated. Data were analysed by ANOVA with Tukey test (mean ± s.d.; P < 0.05), after the normality and homoscedasticity of residuals were checked with Shapiro-Wilk test and Levene test, respectively, when necessary log-transformation was applied. All statistical procedures was performed with R® software. The echogenicity of parenchymas were different (P < 0.05) between pubertal and mature rams for vesicular glands (181.51 ± 20.80 v. 164.83 ± 26.79) and bulbourethral glands (166.93 ± 16.93 v. 141.80 ± 29.15); however, there was no difference (P > 0.05) for prostate glands (99.39 ± 36.34 v. 87.47 ± 34.24). The pixel heterogeneity did not differ (P > 0.05) between pubertal and mature rams (29.06 ± 2.67 v. 28.09 ± 3.95, 32.14 ± 8.20 v. 30.28 ± 4.71, and 27.82 ± 4.53 v. 28.74 ± 4.29) for vesicular, prostate, and bulbourethral glands, respectively. In conclusion, the sexual maturity only influenced the echogenicity of vesicular and bulbourethral parenchymas of Dorper rams.

Reproduction in sympatric lizards: comparison of two species of Ctenotus (Scincidae) in south-eastern Australia

2004 ◽  
Vol 52 (6) ◽  
pp. 649 ◽  
Author(s):  
Jennifer E. Taylor
Keyword(s):  
Sexual Maturity ◽  
New South ◽  
Early Spring ◽  
Reproductive Characteristics ◽  
Sparse Vegetation ◽  
South Wales ◽  
Open Forest ◽  
Eastern Australia ◽  
Testis Volume ◽  
Myall Lakes

The scincid lizards Ctenotus robustus and C. taeniolatus occur sympatrically in regenerating, sand-mined areas in the Port Stephens–Myall Lakes region, coastal New South Wales, Australia. They are absent from the unmined open forest of the area. The reproductive characteristics of these two species were compared. Males reached sexual maturity at a smaller snout–vent length (SVL) than females in C. robustus (72 mm v. 78 mm) and C. taeniolatus (49 mm v. 52 mm). Males were reproductive from August to December and maximum testis volume in both species occurred in early spring; minimum testis volume was recorded in early autumn. Females of both species contained yolking follicles or eggs from October to January (spring–summer). Clutch size in C. robustus (4–9) did not differ significantly from that in C. taeniolatus (2–7) when SVL was accounted for. Both species laid eggs in nests dug 4–5 cm deep in open sandy areas with sparse vegetation, and nesting requirements might explain their absence from open forest. At hatching, C. robustus averaged 35.9 mm SVL and C. taeniolatus averaged 29.9 mm SVL. Hatchlings of both species were at field sites from mid-January to early April. Overall, reproductive characteristics of C. robustus and C. taeniolatus were generally similar.

scholarly journals Reproductive biology and embryonic development of Centroscymnus coelolepis in Portuguese mainland waters

2003 ◽  
Vol 60 (6) ◽  
pp. 1335-1341 ◽  
Author(s):  
Ana Veríssimo ◽  
Leonel Gordo ◽  
Ivone Figueiredo
Keyword(s):  
Sex Ratio ◽  
Embryonic Development ◽  
Reproductive Biology ◽  
Sexual Maturity ◽  
Sampling Period ◽  
Yolk Sac ◽  
Pregnant Female ◽  
Reproductive Parameters ◽  
Reproductive Characteristics ◽  
Total Length

Abstract A total of 871 females (76–122 cm) and 86 males (68–100 cm) of Centroscymnus coelolepis caught in Portuguese mainland waters were examined for reproductive characteristics. One hermaphroditic individual of 95 cm was found. Males were few in numbers and dominated by immature specimens. Female length at first sexual maturity was 98.5 cm. Mean ovarian and uterine fecundity were 13.2 oocytes per female and 9.9 embryos per pregnant female, respectively. Total length of embryos with completely absorbed external yolk sacs ranged between 233 and 300 mm. Sex ratio (F/M) of embryos with completely absorbed external yolk sac was 0.9. All stages of reproduction were found during the 12-month sampling period. Results were compared with those from other regions. A hypothesis is formulated on the existence of several regional populations based on morphometric and reproductive parameters observed in different areas.

Reproductive characteristics of the Pyrenean high-mountain lizards: Iberolacerta aranica (Arribas, 1993), I. aurelioi (Arribas, 1994) and I. bonnali (Lantz, 1927)

2005 ◽  
Vol 55 (2) ◽  
pp. 163-190 ◽  
Author(s):  
Pedro Galán ◽  
Oscar Arribas
Keyword(s):  
Clutch Size ◽  
Reproductive Cycle ◽  
Reproductive Potential ◽  
Activity Cycle ◽  
Field Studies ◽  
Climatic Conditions ◽  
Distribution Area ◽  
High Mountain ◽  
Time Data ◽  
Reproductive Characteristics

AbstractThe three lacertid lizards species of the Iberolacerta genus, which have recently been described or recognised as different species, are reptiles that live strictly at the highest altitudes in Europe, from elevations of near 1900 up to more than 3000 m a.s.l. in the Pyrenees (Spain, Andorra, France). In this paper, the reproductive cycle and reproductive characteristics of these species are described for the first time. Data were obtained from field studies carried out in different high-mountain Pyrenean locations from 1989–2002. In addition we also conducted hatching studies in laboratory. Due to the harsh climatic conditions in the high mountains the activity cycle of these species is very short, just over 4 months, from mid-May to late September or beginning of October. This affects their reproductive cycle (i.e., only one annual egg-clutch is produced), as well as other reproductive characteristics, as the existence of a very advanced embryonic development at oviposition, which is interpreted as an advanced stage in the tendency towards viviparity, and diverse life history characteristics as a very little annual growth which greatly delays sexual maturity to 4 years in males and 4–5 years in females. Clutch size correlates significantly with female snout-vent length (SVL) in all three species. The average clutch size is 2.53 eggs in I. aurelioi (the smallest species), 3.03 in I. bonnali and 3.44 in I. aranica (the biggest species). Notwithstanding the differences in egg number the three species have a similar egg volume. The incubation period in the laboratory is very short with an average of 30–36 days among the species. The low reproductive potential observed in these three species and revealed in this paper is a strongly threatening factor which, together with their extremely reduced distribution area, endangers these endemic, rare and very threatened species.

Observations on the Reproductive Potential of Melanoplus bilituratus (Wlk.) (Orthoptera: Acrididae) Reared on Different Food Plants in the Laboratory

1958 ◽  
Vol 90 (8) ◽  
pp. 483-485 ◽  
Author(s):  
R. Pickford
Keyword(s):  
Reproductive Potential ◽  
Field Conditions ◽  
Food Plants ◽  
Mixed Diet ◽  
Average Production ◽  
Number Of Authors

The fecundity of the migratory grasshopper, Melanoplus bilituratus (Wlk.), when reared under a variety of conditions, has been reported by a number of authors. In the laboratory, Barnes (1955), rearing cultures of the subspecies found in Arizona on five separate foods, obtained an average production of 8.8 egg-pods per female from those fed the most favourable diet; Parker (1930) reported an average production of 8.8 egg-pods per female from Montana specimens reared on a mixed diet; one of these females laid 15 egg-pods. Under field conditions, Pfadt (1949) in Wyoming and Smith et al. (1952) in Manitoba reared this species on a variety of food plants and reported that the greatest numbers of egg-pods per female resulting from use of the most favourable food plants were 9.8 and about 6 egg-pods, respectively.

Recovery of fertility from adult ovarian tissue transplanted into week-old Japanese quail chicks

2015 ◽  
Vol 27 (2) ◽  
pp. 281 ◽  
Author(s):  
Jianan Liu ◽  
Kimberly M. Cheng ◽  
Frederick G. Silversides
Keyword(s):  
Japanese Quail ◽  
Sexual Maturity ◽  
Egg Production ◽  
In Vitro Maturation ◽  
Ovarian Tissue ◽  
Reproductive Potential ◽  
Special Importance ◽  
Old Japanese ◽  
Cryopreserved Ovarian Tissue

Fertility of cryopreserved ovarian tissue from immature chickens and Japanese quail has been recovered by transplantation. This is of special importance for non-mammalian vertebrates in which cryopreservation and in vitro maturation of oocytes are challenging because their oogenesis is characterised by vitellogenesis. This study tested whether fertility of adult quail ovarian tissue could be recovered by transplantation. Ovaries were isolated from mature Japanese quail hens, trimmed, cut into 3- to 4-mm2 pieces and transplanted into ovariectomised, week-old chicks. Recipients were administered an immunosuppressant for two weeks. Ten of 12 recipients survived until sexual maturity and seven laid eggs, but all stopped laying by 17 weeks of age. The age at first egg of recipients laying eggs (75.7 ± 4.2 days) was greater than that of untreated hens (51.8 ± 1.7 days) and egg production of recipients during the laying period (21.7 ± 5.7) was less than that of untreated hens (60.8 ± 3.5). Recipients were paired with males from the WB line for test mating. Only two hens laid eggs during the test period but both produced 100% donor-derived offspring. This research demonstrated that the reproductive potential of ovarian tissue from adult quail hens can be restored by transplantation.

Aspects of ecology of the threatened ringed sawback turtle, Graptemys oculifera

1991 ◽  
Vol 12 (2) ◽  
pp. 161-168 ◽  
Author(s):  
Christopher P. Kofron
Keyword(s):  
Sexual Maturity ◽  
River System ◽  
Pearl River ◽  
Museum Specimens ◽  
Adult Males ◽  
Important Food ◽  
The Third ◽  
The Pearl River ◽  
The U.S ◽  
Growth And Reproduction

AbstractThe ringed sawback turtle, Graptemys oculifem, is endemic to the Pearl River system of Louisiana and Mississippi in southern USA. In 1986 the species was placed on the U.S. Federal List of Endangered and Threatened Species with status designation of 'threatened'. Existing museum specimens were examined to determine geographic distribution, food, growth and reproduction. Caddisflies, dipteran flies, mayflies, beetles and plant material were the most important food. Many stomachs contained small pieces of wood, suggesting that fallen tree trunks were a "grazing" substrate. Males ranged from 3.2-8.6 cm plastron length, and attained sexual maturity during the third or fourth year at lengths of about 6.0-7.0 cm. Adult males experienced recrudescence of testes, with maximum testis lengths during August and September indicating the probable time of spermatogenesis. Females ranged from 3.3-18.9 cm plastron length, and appeared to attain sexual maturity during the seventh or eighth year at lengths greater than 10.0 cm. The data suggested that ovulation occurs from May through July, nesting during June and ,July, and hatching at least during August. Clutch size appeared to be just two or three eggs.

scholarly journals Reproductive characteristics of wild boar males (Sus scrofa) under different environmental conditions

2019 ◽  
Vol 88 (4) ◽  
pp. 401-412 ◽  
Author(s):  
Jakub Drimaj ◽  
Jiří Kamler ◽  
Martin Hošek ◽  
Jaroslav Zeman ◽  
Radim Plhal ◽  
...  
Keyword(s):  
Wild Boar ◽  
Environmental Conditions ◽  
Sexual Maturity ◽  
Reproductive Potential ◽  
Live Weight ◽  
Modern Human ◽  
The Body ◽  
Human Society ◽  
Sperm Production ◽  
Permanent Increase

The wild boar population has been on a permanent increase over the last decades, causing conflicts with the requirements of modern human society. Existing effort to stabilize wild boar numbers generally fails with one of the causes being the high reproductive potential of wild boar. The aim of this study was to assess the onset of sexual maturity in wild boar males with regard to age, physical frame and environmental conditions on the basis of testicle development and sperm production. This study assessed the dimensions of gonads and the occurrence of sperm in boars caught during common hunts. Environmental conditions were found as an important factor for growth and sexual maturity of wild boar males. The body weight was a more important factor for sperm production than the age of young wild boar males. The weight threshold for sperm production in the testes was 29 kg of live weight, which corresponds to 6 months of age on average. This study has proven that environmental conditions are a significant factor affecting the physical development of male wild boars, more specifically the growth rate of their body frames and the onset of sexual maturity. In a better quality environment boars grow faster and enter puberty at an earlier age. Poor food supply and/or high hunting pressure result in slower body and testicular growth, as well as the production of sperm at a later age (approx. 2-3 months later).

scholarly journals Select biological characteristics of the mossul bleak Alburnus mossulensis Heckel, 1843(Actinopterygii: Cyprinidae) in the Ataturk Dam Lake, Turkey

2018 ◽  
Vol 65 (4) ◽  
Author(s):  
Arif Parmaksız ◽  
Ahmet Oymak ◽  
Necmettin Dogan ◽  
Erhan Unlu
Keyword(s):  
Sexual Maturity ◽  
Condition Factor ◽  
Age Groups ◽  
Fork Length ◽  
Biological Characteristics ◽  
Regression Equations ◽  
Reproductive Characteristics ◽  
Absolute Fecundity ◽  
Weight Relationship ◽  
Atatürk Dam Lake

Maturity, growth and reproductive characteristics of the mossul bleak Alburnus mossulensis, from Ataturk Dam Lake (Euphrates) were assessed. Maturity composition of the analysed samples varied between age groups I and VII. The ratio of females to males was 1.047:1. Fork length of the samples varied between 40-198 mm and weights were in the range of 0.45-68 g. The regression equations derived for the length-weight relationship was Log W = -5.5531+3.2958 Log FL (r2=0.9593) for females and Log W=-5.3695+3.2112 Log FL (r2=0.9487) for males. Mean condition factor was determined as 1.069 for females and 1.062 for males. Absolute fecundity was established to be between 288 and 3380. The age of sexual maturity was 3 years in females and 2 years in males.

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