Spontaneous lactation is an adaptive result of pseudopregnancy

  title={Spontaneous lactation is an adaptive result of pseudopregnancy},
  author={Scott R. Creel and Steven L. Monfort and David E. Wildt and Peter M. Waser},
LACTATION is almost exclusively associated with pregnancy and giving birth. Although lactation can be induced without a preceding pregnancy in some species, this requires exogenous hormones, artificially intense or extended suckling or both1,2. Spontaneous lactation, lactation by females that have neither been pregnant nor experimentally manipulated, is extremely unusual among eutherians3–8. Among nondomesticated animals, spontaneous lactation has been observed repeatedly only in the dwarf… 

MilK ProduCtion oF PseudoPreGnant MultiParous does

It is demonstrated that multiparous empty does, pseudopregnant or non-pseudopregnancy, can produce milk, but in lower quantities than multiparrous does after kindling.

Reproduction triggers adaptive increases in body size in female mole-rats

It is shown that, in captive Damaraland mole-rats (Fukomys damarensis), where breeding was experimentally controlled in age-matched siblings, individuals changed in size and shape through a lengthening of the lumbar vertebrae when they began breeding, and it is suggested that the increases in female body size provide fecundity benefits.

Male lactation: why, why not and is it care?

Parity predicts allonursing in a cooperative breeder

Investigation of the likelihood and duration of allonursing by subordinate female meerkats (Suricata suricatta) found that nonpregnant nulliparous females were less likely to allonurse than nonPregnant primIParous and multiparous Female, although parity was not related to variation in allonursesing duration.

The immunological function of allosuckling.

The immunological function of allosuckling hypothesis is developed and the IFA may provide a new explanation as to why neonates suckle various females and why foster females often refuse to nurse nonoffspring.



Serum levels of luteinizing hormone and progesterone during the estrous cycle, pseudopregnancy and pregnancy in the dog.

In all nonpreg-nant animals, the pattern of progesterone secretion after day 10 was similar: decreasing from day 10 and subsequently waning to nondetectable levels (<0.5 ng/ml) by 80 days after the LH peak.

Induction by young of prolonged dioestrus in virgin rats behaving maternally.

The present investigation examined, by study of daily vaginal smears, whether the interaction of virgin female rats with young affected the oestrous cycle and found body contact with young was sufficient to induce dioestrus in maternal virgins with excised nipples.

Plasma levels of estradiol and progesterone in the cat during polyestrus, pregnancy and pseudopregnancy.

The levels of estradiol and progesterone in the systemic plasma of four domestic cats during pregnancy, pseudopregnancy and polyestrus were determined by radioimmunoassay. During polyestrus,

Endocrine correlates of reproduction in the wolf. I. Serum progesterone, estradiol and LH during the estrous cycle.

The estrous cycle of 10 intact female wolves, aged 8 months-8 years at the initiation of the study, was characterized in terms of vaginal smears, behavioral observations and serum concentrations of

Relactation: an overview.

Although relactation is an accepted fact in many cultures, even well-trained pediatricians in both the developed and developing countries may be unaware of the potential relactations has in good infant care.

Total unconjugated oestrogen and progesterone concentrations in peripheral blood during pregnancy in the dog.

  • J. C. Hadley
  • Medicine
    Journal of reproduction and fertility
  • 1975
Daily blood samples were withdrawn from three bitches throughout gestation and at intervals during parturition to detect oestrogen rise and progesterone decline, which could not be detected after the end of parturitions.

Lactation and care for unrelated infants in forest‐living ringtailed Lemurs

An adult female ringtailed lemur (Lemur catta) known not to have been pregnant showed spontaneous lactation in response to twin infants born to an unrelated female, and like the two maternal females, frequently attacked unfamiliar immigrating adult males when the males approached the infants.