scholarly journals Adaptive adjustment of the sex ratio: more data and considerations from a fallow deer population

1998 ◽  
Vol 9 (4) ◽  
pp. 404-408 ◽  
Author(s):  
Björn Birgersson
Keyword(s):  
Sex Ratio ◽  
Fallow Deer ◽  
Deer Population ◽  
Adaptive Adjustment

scholarly journals Sperm sex ratio adjustment in a mammal: perceived male competition leads to elevated proportions of female-producing sperm

2020 ◽  
Vol 16 (6) ◽  
pp. 20190929
Author(s):  
Renée C. Firman ◽  
Jamie N. Tedeschi ◽  
Francisco Garcia-Gonzalez
Keyword(s):  
Sex Ratio ◽  
Sex Allocation ◽  
Sex Ratios ◽  
Female Offspring ◽  
Male Competition ◽  
Offspring Sex ◽  
Sex Ratio Adjustment ◽  
Adaptive Adjustment ◽  
Male House

Mammal sex allocation research has focused almost exclusively on maternal traits, but it is now apparent that fathers can also influence offspring sex ratios. Parents that produce female offspring under conditions of intense male–male competition can benefit with greater assurance of maximized grand-parentage. Adaptive adjustment in the sperm sex ratio, for example with an increase in the production of X-chromosome bearing sperm (CBS), is one potential paternal mechanism for achieving female-biased sex ratios. Here, we tested this mechanistic hypothesis by varying the risk of male–male competition that male house mice perceived during development, and quantifying sperm sex ratios at sexual maturity. Our analyses revealed that males exposed to a competitive ‘risk’ produced lower proportions of Y-CBS compared to males that matured under ‘no risk’ of competition. We also explored whether testosterone production was linked to sperm sex ratio variation, but found no evidence to support this. We discuss our findings in relation to the adaptive value of sperm sex ratio adjustments and the role of steroid hormones in socially induced sex allocation.

scholarly journals Assessment of a daily defecation rate of fallow deer upon a closed population study

2012 ◽  
Vol 60 (6) ◽  
pp. 173-180 ◽  
Author(s):  
Antonín Košnář ◽  
Romana Rajnyšová
Keyword(s):  
Population Density ◽  
Fallow Deer ◽  
Early Spring ◽  
Summer Season ◽  
Accurate Assessment ◽  
Indirect Methods ◽  
Defecation Rate ◽  
Closed Population ◽  
Deer Population ◽  
Precise Knowledge

Many indirect methods of counting even-toed ungulates are based on the principle of accumulating dung in a known area per a unit of time. In order to provide the most accurate assessment of the population size, these methods require the knowledge of daily defecation of the monitored species. The main objective of the study submitted is the assessment of a daily defecation rate of fallow deer based on the monitoring of its closed population. A partial objective is the assessment of the distribution of fallow deer in an enclosed area with a view to biotopes represented. A fallow deer population was studied for the period of three years (2009–2011) in a fenced-in area (8 ha). During this period, dung heaps were counted in forty sites with the total area of 0.8 ha in all seasons of the year. In each season, the sites were cleared, and the dung was counted after a seven-day exposure. This counting was performed twice in each season. Thanks to the precise knowledge of the number of monitored animals, daily defecation rates (DDR) were derived upon the dung found, using a formula for the calculation of population density. Subsequently, the determined DDRs were verified by direct observation. The highest average DDR value calculated from the formula (21.11 ± 0.32 S.E.) was obtained in the summer season. The lowest defecation of fallow deer was established to be in winter (12.34 ± 0.25 S.E.) and early spring (10.61 ± 0.24 S.E.).

scholarly journals Fallow Deer (Dama dama) as a Reservoir of Shiga Toxin-Producing Escherichia coli (STEC)

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 881
Author(s):  
Anna Szczerba-Turek ◽  
Bernard Kordas
Keyword(s):  
Escherichia Coli ◽  
Polymerase Chain Reaction ◽  
Foodborne Pathogens ◽  
Shiga Toxin ◽  
Fallow Deer ◽  
Dama Dama ◽  
Chain Reaction ◽  
E Coli ◽  
Deer Population ◽  
Polymerase Chain

Shiga toxin-producing Escherichia (E.) coli (STEC) are responsible for the outbreaks of serious diseases in humans. Only a few reports on fallow deer as a reservoir of foodborne pathogens have been published to date. The purpose of this study was to determine the occurrence of STEC strains in the fallow deer population in Poland. In all, 94 fallow deer swabs were tested. Polymerase chain reaction (PCR) was performed to detect the virulence profile of stx1, stx2 and eae or aggR genes, to identify the subtypes of stx1 and stx2 genes and to perform O and H serotyping. STEC and attaching and effacing (AE)-STEC were identified in 13 isolates (13.83%). The most hazardous virulence profile was detected in three strains, namely stx2d serotype O103:HNM, eae/stx1a serotype O26:HNM and eae/stx1a serotype O157:H7. The predominant stx gene was stx2, which was identified in 76.92% of isolates. E. coli O157 was detected in 4/94 (4.26%). Other E. coli serogroups, O26, O103, O111 and O145, were identified in 14/94 fallow deer (14.89%). The present findings suggest that fallow deer are carriers of STEC/AE-STEC that are potentially pathogenic to humans.

scholarly journals Coexistence of Territoriality and Harem Defense in a Rutting Fallow Deer Population

1990 ◽  
Vol 71 (4) ◽  
pp. 692-695 ◽  
Author(s):  
F. Alvarez ◽  
F. Braza ◽  
C. S. Jose
Keyword(s):  
Fallow Deer ◽  
Deer Population

The spatio-temporal co-occurrence of free-ranging common fallow deer and domestic caprines on the island of Rhodes, Greece

Mammalia ◽  
2021 ◽  
Vol 85 (3) ◽  
pp. 227-230
Author(s):  
Anna M. De Marinis ◽  
Marco Masseti
Keyword(s):  
Fallow Deer ◽  
Greek Population ◽  
Dama Dama ◽  
Abundance Index ◽  
Deer Population ◽  
The Status ◽  
Spatio Temporal ◽  
Free Ranging ◽  
Genetic Characters ◽  
Over Time

Abstract The Dama dama dama population of the island of Rhodes has an important conservation significance because of its unique genetic characters. Currently, many are the factors that threaten its survival. Aim of this paper is to provide the first data on the spatio-temporal co-occurrence between the only free-ranging Greek population of common fallow deer and local domestic caprines. Kilometric abundance index (KAI) was derived from spotlight counts. The unattended domestic caprines appear to impact on fallow deer, in particular during fawning season. Livestock monitoring over time can act as a proxy indicator of the status of this deer population.

Testing models of adaptive adjustment of secondary sex ratio in domestic swine

1997 ◽  
Vol 53 (2) ◽  
pp. 428-431 ◽  
Author(s):  
DOUGLAS B MEIKLE ◽  
STEPHEN H VESSEY ◽  
LEE C DRICKAMER
Keyword(s):  
Sex Ratio ◽  
Secondary Sex Ratio ◽  
Adaptive Adjustment ◽  
Domestic Swine

Testing Density Estimators on a Fallow Deer Population of Known Size

1996 ◽  
Vol 60 (1) ◽  
pp. 18 ◽  
Author(s):  
Jean-Paul Vincent ◽  
A. J. Mark Hewison ◽  
Jean-Marc Angibault ◽  
Bruno Cargnelutti
Keyword(s):  
Fallow Deer ◽  
Deer Population ◽  
Density Estimators
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