Paternal care in captive collared lemmings (Dicrostonyx richardsoni) and its effect on development of the offspring

We examined parental care in captive collared lemmings (Dicrostonyx richardsoni) to determine how this behavior differed between sexes and to test the hypothesis that presence of the male with the litter from parturition to weaning (17 d) would affect preweaning rates of growth, behavioral development, and body size and aggression at sexual maturity. Also, we tested whether stressing the litter, by removal of the female for 8 h/d, would alter the effect of the male on the development of pups. We compared four treatments: pups raised with mother only, pups raised with both parents, stressed pups raised with mother only, and stressed pups raised with both parents. Parental behavior was recorded from parturition to weaning. Preweaning development of pups was measured by rate of weight gain, age of eye opening, and development of thermoregulation and righting ability. Comparisons were made between stressed and unstressed litters raised with or without the sire. At 25 d, pups were weighed again and isolated, and at 60–75 d, their intrasexual aggressive behavior was measured. Presence of the sire did not alter behavior of the dam, and except for lactation, males and females cared equally for the pups. At weaning, stressed pups weighed less than unstressed pups, but this difference disappeared by 25 d. Presence of the sire had no effect on aggression of male or female offspring at 75 d. We concluded that the paternal care shown in this species is either an artifact of laboratory conditions or that it has effects, such as protection of offspring from infanticide or alleviation of thermal stress, that were not examined in this study.

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Comparison of body size, relative growth and size at onset sexual maturity of Uca uruguayensis (Crustacea: Decapoda: Ocypodidae) from different latitudes in the south-western Atlantic

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315412001038 ◽

2012 ◽

Vol 93 (3) ◽

pp. 781-788 ◽

Cited By ~ 24

Author(s):

Gustavo Luis Hirose ◽

Vivian Fransozo ◽

Carolina Tropea ◽

Laura S. López-Greco ◽

Maria Lucia Negreiros-Fransozo

Keyword(s):

Body Size ◽

Sexual Maturity ◽

Fiddler Crab ◽

Carapace Width ◽

The Body ◽

Brazilian Population ◽

The South ◽

Western Atlantic ◽

Males And Females ◽

Uca Uruguayensis

Some crustaceans show variations of their reproductive biology within their geographical distribution, and knowledge about such variations is important for the comprehension of their reproductive adaptations. This study compared two populations of the fiddler crab Uca uruguayensis from two locations on the south-western Atlantic coast: Ubatuba Bay, São Paulo, Brazil and Samborombón Bay, Buenos Aires, Argentina. The population features analysed were the body size variation (carapace width = CW) and the size at the onset of sexual maturity (SOM) in order to test the hypothesis that the size at SOM, should be the same in relative terms (RSOM), independently of the latitudinal position. In the Brazilian population the CW ranged from 4.18 to 11.60 mm for males and 3.90 to 9.80 mm for females, and in the Argentinean population from 3.60 to 14.10 mm for males and 2.85 to 12.00 mm for females. In the Brazilian population the SOM was 7.1 (RSOM = 0.58) and 5.9 mm CW (RSOM = 0.57) for males and females, respectively, and in the Argentinean population it was 7.0 (RSOM = 0.42) and 6.75 mm CW (RSOM = 0.53) for males and females, respectively. This fact is probably related to a great plasticity in the life history features of Uca uruguayensis under different environmental conditions.

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Reproduction, seasonal activity and growth of the coral snake, Micrurus corallinus (Elapidae), in the southeastern Atlantic forest in Brazil

Amphibia-Reptilia ◽

10.1163/156853896x00441 ◽

1996 ◽

Vol 17 (3) ◽

pp. 277-285 ◽

Cited By ~ 18

Author(s):

Otavio A.V. Marques

Keyword(s):

Body Size ◽

Rainy Season ◽

Sexual Maturity ◽

Seasonal Patterns ◽

Field Observations ◽

Seasonal Activity ◽

Coral Snake ◽

Males And Females ◽

Age And Sex ◽

Southeastern Atlantic

AbstractDissection of 360 specimens of the coral snake Micrurus corallinus, combined with data on captive individuals and field observations, provided information on the reproductive ecology of this elapid snake. Clutch size ranged from 2 to 12 eggs, and was correlated with maternal body size. Reproduction seems to be highly seasonal, with mating and vitellogenesis occurring at the onset of the rainy season, oviposition in mid rainy season, and hatching at the end of the rainy season and early dry season. Incubation in the laboratory ranged from 78 to 93 days. Neonates measured 177-197 mm snout-vent length and weighed 2.02-2.76 g. Growth of juveniles is quick, with both males and females attaining sexual maturity at an age of about 18 months. Seasonal patterns of surface activity seem to be related to age and sex.

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Sexual dimorphism in the Neotropical lizard, Tropidurus torquatus (Squamata, Tropiduridae)

Amphibia-Reptilia ◽

10.1163/1568538054253384 ◽

2005 ◽

Vol 26 (2) ◽

pp. 127-137 ◽

Cited By ~ 30

Author(s):

Helga Wiederhecker ◽

Adriana Pinto ◽

Guarino Colli

Keyword(s):

Body Size ◽

Sexual Dimorphism ◽

Sexual Maturity ◽

Body Shape ◽

Patch Size ◽

Adult Males ◽

Lizard Species ◽

Central Brazil ◽

Adult Females ◽

Males And Females

AbstractWe describe the sexual dimorphism in coloration, body shape, and body size in Tropidurus torquatus, a widely distributed lizard species in central Brazil. Adult males have colored patches varying from yellow to yellow-and-black, and black on the abdomen, ventral aspect of the thighs, and pre-cloacal flap. Adult females lack ventral colored patches. During ontogeny, there is a gradual darkening of the patches, but no modification either in patch size or color is associated with the reproductive cycle. Adult males have wider heads and thinner bodies than females of the same body size. Males and females grow at the same rate prior to sexual maturity, but males take longer to reach sexual maturity, maturing at a larger body size than females.

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Body size and age structure of the endangered Clark’s lizard (Darevskia clarkorum) populations from two different altitudes in Turkey

Amphibia-Reptilia ◽

10.1163/15685381-00003073 ◽

2016 ◽

Vol 37 (4) ◽

pp. 450-456 ◽

Cited By ~ 3

Author(s):

Ufuk Bülbül ◽

Muammer Kurnaz ◽

Ali İhsan Eroğlu ◽

Halime Koç ◽

Bilal Kutrup

Keyword(s):

Body Size ◽

Age Structure ◽

Sexual Maturity ◽

Age At Maturity ◽

Maximum Life Span ◽

Breeding Populations ◽

Size And Age Structure ◽

Males And Females ◽

The Mean ◽

Different Altitudes

We investigated age structure, body size and longevity in two breeding populations ofDarevskia clarkoruminhabiting altitudes ranging from 450 m a.s.l. (Kamilet) to 2250 m a.s.l. (Başyayla) in Turkey by skeletochronology performed on the phalanges. The mean age was found to be 6 years in the Kamilet population and 7 years in the Başyayla population. The maximum life span was 10 years in the lowland population while it was 12 years in the highland population. Age at sexual maturity of both males and females was 1-2 years in the lowland population while it was 2-3 for both sexes in the highland population. Both age and SVL of specimens from the Kamilet population were significantly different between the sexes while age and SVL did not differ significantly between the sexes in Başyayla population. As a conclusion, we observed that the mean age, longevity and age at maturity were increased by altitude while there was a decrease based on the mean SVL in the highland population ofD. clarkorum. Our data on body size, longevity and age at sexual maturity may contribute to conservation efforts for this endangered species.

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Variation within and between Rivers in Adult Size and Sea Age at Maturity of Anadromous Brown Trout, Salmo trutta

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f91-119 ◽

1991 ◽

Vol 48 (6) ◽

pp. 1015-1021 ◽

Cited By ~ 29

Author(s):

Jan Henning L'Abée-Lund

Keyword(s):

Brown Trout ◽

Sexual Maturity ◽

Salmo Trutta ◽

Adult Size ◽

Age At Maturity ◽

Migration Distance ◽

Spawning Area ◽

Brown Trout Salmo Trutta ◽

Males And Females ◽

The Mean

I compared adult size and sea age at sexual maturity among nine populations of anadromous brown trout, Salmo trutta, in two Norwegian rivers to determine the extent of inter- and intrariverine variations. Variation in the mean length of spawners and in the mean sea age at sexual maturity were mainly dependent on the variations found within rather than between rivers. Mean lengths and mean age at maturity of males increased significantly with increasing altitude of the spawning area and with migration distance in freshwater. In females, positive significant correlations were found with mean lengths and altitude of the spawning area and with mean sea age at maturity and both spawning site altitude and migration distance. Mean lengths and ages of males and females were not significantly correlated with the rate of water discharge in the streams during spawning. The size of gravel substrate for spawning was of minor importance in explaining interpopulation variation in mean female size. The increase noted in mean length and in mean sea age at maturity of both males and females is probably an adaptation to greater energy expenditure to reach the uppermost natal spawning areas.

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Morphometrics and molecular analysis ofOzolaimus linstowin. sp. (Oxyuroidea: Pharyngodonidae) from the green lizardIguana iguana

Journal of Helminthology ◽

10.1017/s0022149x15000061 ◽

2015 ◽

Vol 90 (2) ◽

pp. 186-198 ◽

Cited By ~ 2

Author(s):

S.V. Malysheva

Keyword(s):

Body Size ◽

Large Subunit ◽

Buccal Capsule ◽

Small Subunit ◽

Present Species ◽

Lsu Rdna ◽

Adult Males ◽

Spicule Length ◽

Males And Females ◽

Characteristic Features

AbstractOzolaimus linstowin. sp. is described from the large intestine ofIguana iguanaLinnaeus, 1758 from Mexico. The present species can be easily distinguished fromO. megatyphlonandO. cirratusby the presence of a long and slender pharynx not divided into sections, more similar to the remaining two species,O. monhysteraandO. ctenosauri. Ozolaimus linstowin. sp. can be differentiated fromO. monhysteraby the shorter spicule length and smaller body size of both males and females. Males ofO. linstowin. sp. are morphologically close to those ofO. ctenosauri, but females possess a markedly smaller body size and differ in the organization of the oral cuticular armature. Adult males ofO. linstowin. sp. bear some characteristic features of the J3 juvenile morphology in terms of the cuticular organization of the oral and buccal capsule. Phylogenetic analysis ofO.linstowin. sp. using partial small subunit (SSU) and D2–D3 large subunit (LSU) rDNA shows relationships with several Oxyuridae genera.

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Variation in Weight, Size, and Sex Ratio of Coccinellid Adults (Coleoptera: Coccinellidae)

The Canadian Entomologist ◽

10.4039/ent98639-6 ◽

1966 ◽

Vol 98 (6) ◽

pp. 639-644 ◽

Cited By ~ 10

Author(s):

B. C. Smith

Keyword(s):

Body Size ◽

Sex Ratio ◽

Water Content ◽

Food Supply ◽

Sexual Differences ◽

Intraspecies Variation ◽

Food Scarcity ◽

Food Requirement ◽

Males And Females

AbstractThe weight and size of coccinellid adults varied with species, sex, and feeding. Intraspecies variation in weight was generally similar in the eight species studied. Females were more variable than males in body size. Females of some species were heavier and larger than males, and species can be classified on a basis of difference in the weight and size of the sexes.An increase in the food supply after a period of food scarcity affected the sex ratio, as the minimum food requirement of females was greater than males. Females increased in weight more rapidly than males after feeding. The availability of food in the field affected the weight and size of some species. Adult water content was influenced by feeding but not by sex or the quantity of food given to the larva.Males were more abundant in species with small sexual differences in weight and size. The degree of difference in weight and size between males and females may be used as a criterion to select species that are best adapted to survive when food is scarce.

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Body size, not age, predicts parasite load in Clark’s Spiny Lizards (Sceloporus clarkii)

Canadian Journal of Zoology ◽

10.1139/cjz-2017-0328 ◽

2019 ◽

Vol 97 (3) ◽

pp. 220-224 ◽

Cited By ~ 3

Author(s):

H.V. Watkins ◽

G. Blouin-Demers

Keyword(s):

Body Size ◽

Surface Area ◽

Intraspecific Variation ◽

Wild Population ◽

Parasite Load ◽

Older Individuals ◽

Fundamental Goal ◽

Males And Females ◽

Ectoparasite Load

Determining the factors that influence parasite load is a fundamental goal of parasitology. Body size often influences parasite load in reptiles, but it is unclear whether higher levels of parasitism are a result of greater surface area of individuals (a function of size) or of longer periods of exposure to parasites (a function of age). Using skeletochronology in a wild population of Clark’s Spiny Lizards (Sceloporus clarkii Baird and Girard, 1852), we tested the hypotheses that (i) larger individuals have higher parasite loads due to increased surface area available for colonization by parasites and their vectors and that (ii) older individuals have higher parasite loads because they have had longer exposure to parasites and their vectors. Males harboured more ectoparasites than females. Males and females differed in how body size influenced chigger (Acari: Trombiculidae) load; larger males harboured more chiggers than smaller males, but this was not the case in females. Age did not affect ectoparasite load in either sex. These results emphasize the importance of disentangling the effects of size and age in models of parasitism to gain a clearer understanding of intraspecific variation in parasite load.

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Influence of gender on carcass yield of twin lambs Blackbelly x Pelibuey at 56 days of age

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-8215 ◽

2016 ◽

Vol 68 (4) ◽

pp. 1077-1084

Author(s):

I. del C. García-Osorio ◽

J. Oliva-Hernández ◽

M.M. Osorio-Arce ◽

G. Torres-Hernández ◽

J. A. Hinojosa-Cuéllar ◽

...

Keyword(s):

Body Weight ◽

Weight Gain ◽

Growth Yield ◽

Daily Weight Gain ◽

Longissimus Dorsi ◽

Average Daily Weight Gain ◽

Carcass Yield ◽

Longissimus Dorsi Muscle ◽

Dorsi Muscle ◽

Males And Females

ABSTRACT The aim of this study was to determine the influence of gender on pre-weaning growth, yield and weight of primal cuts of the carcass of Blackbelly x Pelibuey lambs. 16 twin lambs were used. The lamb gender was the fixed factor. The variables evaluated were: body weight at birth and at weaning, average daily weight gain, weight and yield of carcass and primal cuts: neck, arm, thorax, abdomen and leg. Gender did not affect (P>0.05) body weight at birth. However, the pre-weaning average daily weight gain and body weight at weaning were affected (P<0.05) by the gender. Hot carcass yield and weight and primal cuts were not affected (P>0.05) by the gender of the lamb. Nevertheless, the area of the Longissimus dorsi muscle and cavity fat were different between males and females (P<0.05) 11.5±0.73cm2 and 198±0.05 g vs 9.3±0.73cm2 and 282±0.05g, respectively. In conclusion, in twin lambs Blackbelly x Pelibuey males had greater average daily weight gain and body weight at weaning than females. Carcass yield and weight and primal cuts were not affected by the gender of the lamb. However, males had greater area of the L. dorsi muscle than females and these in turn had a greater amount of cavity fat than males.

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