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1

Frequency distribution of conception dates in a white-tailed deer herd

100%
Rhodes O. E., Jr. Nowak J. M., Smith M. H., Johns P. E.
Acta Theriologica
|
1991
|
tom 36
|
nr 1-2
2

Spermatozoan numbers and characteristics of associated organs in male white-tailed deer during the breeding season

100%
Peles J. D., Rhodes O. E., Smith M. H.
Acta Theriologica
|
2003
|
tom 48
|
nr 1
Short-term changes in testicular spermatozoa, testes weight, testes length, epididymes weight, epididymal spermatozoa, and body weight of adult and yearling male white-tailed deerOdocoileus virginianus (Zimmermann, 1780) were examined over a 9-week period that included the peak of the breeding season in South Carolina. Mean values for all characteristics were significantly greater in adults compared to yearlings. Values for reproductive characteristics tended to be highest during the last week in October or the first week in November and decreased over the course of the investigation. Body weight of adults decreased from late October through early December, whereas body weight of yearlings fluctuated only slightly throughout the 9-week period. Significant correlations were observed among all reproductive characteristics and body weight was highly correlated with all characteristics except testicular spermatozoa. Values for reproductive characteristics differed significantly between the right and left sides of the reproductive tracts. Results demonstrate the occurrence of short-term changes in reproductive capabilities of white-tailed deer that are relevant for the development of management strategies for this species
3

Morphological asymmetry in mammals: genetics and homeostasis reconsidered

100%
Novak J. M., Rhodes O. E., Smith M. H., Chesser R. K.
Acta Theriologica. Supplement
|
1993
|
tom 38
|
nr 2
It has been hypothesized that developmental stability is increased at higher levels of genetic variability (heterozygosity) in animals. However, the existence of this relationship is questionable for homeotherms in general and mammals in particular. The difference between the sides of a bilateral character in an individual is a measure of fluctuating asymmetry that can be used as a measure of the developmental stability of mammals. Increased developmental stability should result in a greater degree of similarity between the right and left side of the body even though environmental variability would tend to increase the differences between right and left sides of the body. It is necessary to separate the effects of the three types of asymmetry so that an accurate estimate of the variance attributable to fluctuating asymmetry can be made. In addition, many early studies of asymmetry in poikilotherms used meristic characters (such as scale counts), and these types of characters are not easily studied in mammals. Mammals, because of their precise regulation of body temperature show little phenotypic effect of environmental variability, and thus may exhibit low absolute levels of asymmetry. Mammals may also be able to reduce the level of asymmetry during their prolonged intrauterine development and juvenile growth period. The literature is reviewed relative to relationships between genetic variation and asymmetry in mammals. Hypotheses are reviewed as they relate to the relationship between fluctuating asymmetry and heterozygosity observed in previous studies. Finally, recommendations are put forth regarding the design and interpretation of future research into the relationship between developmental homeostasis and genetic variability.
4

Spermatozoan numbers and testicular characteristics of male white-tailed deer fawns during the mating season

100%
Peles J. D., Rhodes O. E., Smith M. H.
Acta Theriologica
|
2000
|
tom 45
|
nr 1
Testicular spermatozoan numbers, testes weight, testes length, body weight, and kidney fat index (KFI) were obtained for male white-tailed deer Odocoileus virginianus (Zimmerman, 1780) fawns during the mating season at the Savannah River Site (SRS) in South Carolina, Mean values for testicular spermatozoa, testes weight, and testes length increased significantly over the study period (late October - late December) whereas body weight and KFI did not change with time. Testicular spermatozoa were found in 28% of all fawns examined and the proportion of sexually mature fawns increased greatly over the course of the study and was highest during December. These findings suggest that mate fawns breed later than adults at a time that coincides with the mean conception date in doe fawns. Testes weight, testes length, body weight, and KFI were significantly greater in fawns with testicular spermatozoa compared to those without testicular spermatozoa. We suggest that testes weight is closely associated with the presence of testicular spermatozoa in fawns from SRS.
5

Evolution of mammalian social structure

88%
Chesser R. K., Sugg D. W., Rhodes O. E., Novak J. M., Smith M. H.
Acta Theriologica. Supplement
|
1993
|
tom 38
|
nr 2
Social groups may be viewed as collections of individuals exhibiting nonindependent behavior and organized in a cooperative manner. The evolutionary advantage of social behavior to individuals must be measured in its relativity to other potential behaviors, the scale of competitive interactions, and under a variety of environmental and genetic constraints. A primary tenet of social evolution is that coancestry will promote the genes of related individuals. High values of coancestry, however, do not necessarily translate into evolutionary advantage unless the primary competitive interactions occur among the groups. Coancestry is affected by the breeding tactics within and rates of genetic exchange among social groups. Low rates of exchange among groups, regardless of breeding tactics, may result in high values for intragroup coancestry but may lead to inbreeding depression in progeny. Likewise, breeding tactics such as polygyny, may not impart any long-lasting evolutionary advantage if genetic exchange rates are high. The evolution of social organizations typified by different breeding and migration strategies is evaluated to determine the conditions necessary for various tactics to result in genetic contributions by individuals equal to those of monogamous mating systems. The models show that breeding and dispersal tactics have probably evolved in concert and predict that social groups which are characterized by strong gene correlations are likely to exhibit relatively low group advantage for progeny survival and breeding. There is little impetus for high gene correlations to accrue in situations where group advantage is very high relative to monogamous systems.
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