Reproductive endocrine patterns in captive female and male red wolves (Canis rufus) assessed by fecal and serum hormone analysis

Abstract

Reproductive steroid profiles in female (n=13) and male (n=5) red wolves (Canis rufus) were characterized in fecal samples collected during the breeding season (December-May) and over a 1 year period, respectively. Blood samples from females (n=12) also were collected during the periovulatory period for luteinizing hormone (LH) and steroid analysis. High performance liquid chromatography (HPLC) of fecal extracts determined that estradiol and estrone constituted the major and minor forms, respectively, of fecal estrogen metabolites. Although native progesterone was present, pregnane metabolites predominated as the major forms of fecal progestins. HPLC analysis of fecal extracts from males revealed no native testosterone, but rather the predominance of more polar androgen metabolites. Based on hormone profiles and/or pup production, females were classified as pregnant (n=3), ovulatory-nonpregnant (n=9), or acyclic (n=3). Longitudinal monitoring of females indicated no pregnancy-specific differences in concentrations of either fecal progestagen or estrogen metabolites compared to ovulatory-nonpregnant individuals; however, baseline progestagen concentrations were consistently elevated in acyclic females. There was good correspondence between serum and fecal steroid concentration during the periovulatory period. A rise in serum estrogens preceded the ovulatory LH surge which was then followed by a significant progesterone rise during the luteal phase. In males, changes in fecal androgen metabolite concentrations coincided with photoperiod fluctuations, increasing in late autumn and reaching peak concentrations during

Patterns of fecal gonadal hormone metabolites in the maned wolf (Chrysocyon brachyurus)

“…This confirms the validity of the enzyme immunoassay procedures for monitoring reproductive ovarian activity in the maned wolf. Similar to the domestic dog [8][9][10], African wild dog [17], gray wolf [18], and red wolf [16], sexual receptivity and ovulation in the maned wolf occurred in the presence of declining estrogen and rapidly rising progestins, reproductive characteristics that are highly conserved among Canidae. The preovulatory progestin rise was most likely due to early follicular luteinization [11].…”

“…Data were transformed by application of a logarithm (base 10) and tested for normality. Longitudinal steroid metabolite profiles were divided into three reproductive stages using modified criteria of those described by Velloso et al [6] and Walker et al [16]: (1) preovulatory phase or basal phase (days À30 to À10), (2) periovulatory phase (days À9 to 9), and (3) luteal phase (days 10-70). Differences in fecal steroid patterns among age categories and among females of different reproductive status within the same reproductive stage were determined by averaging individual means, followed by comparisons by analysis of variance (ANOVA, SigmaStat 3.0, SPSS Inc., Chicago, IL, USA).…”

The Contribution of the Captive Breeding in Mexican Grey Wolf (<i>Canis lupus baileyi</i>) and Red Wolf (<i>Canis rufus</i>)

“…Finally, 14 individuals have been chosen as the initial founders of captive breeding (Phillips et al, 2003).However, the issues about the genetic purity and specialness of this population have been argued (Roy et al, 1994). The 14 founders have been examined to obtain the biological information (Miller et al, 2003) and figured out the relationship with other canids species and the ancestors of these founders (Walker et al, 2002).…”

“…examined the juvenile viability and there was no serious inbreeding phenomenon in this population . Until now, the initial founders were still under strictly management in order to save the available genetic value for the future (Walker et al, 2002).…”

Foreword: A perspective on the role of emerging technologies for the propagation of companion animals, non-domestic and endangered species

“…In companion animals, hormone analysis is not as widespread (with the exception of progesterone and luteinising hormone analysis to determine ovulation in dogs) due to the feasibility of applying behavioural observation, palpation and ultrasound techniques for oestrus and pregnancy detection. However, non-invasive hormone monitoring has been a prerequisite for assessing reproductive parameters in non-domestic species, particularly wild felids (Brown et al 1996(Brown et al , 2001, canids (Walker et al 2002;Songsasen et al 2006) and cervids (Monfort et al 1990;Kapke et al 1999).…”