Hot Weather Breeding Hot weather takes its toll on animals, but
especially the male breeding dog. Male dog fertility peaks
around 5 years of age as does the female, but can breed and
settle females long after 5 years if managed for fertility.
Season of the Year: Research tells us the season of the year
does have an effect on concentration of sperm per ejaculate.
Increase concentration occurs in Spring/Early Summer and lower
concentration in Late Summer/Fall (Tahs 1981). Sperm
concentration is thought to be influenced by photoperiod (day
length) and the environmental temperature. One or both can be
controlled. Though the concentration of sperm fluctuates, the
normal dog is still fertile and can settle females any time of
the year if managed well. The testicle is outside the body in
the scrotum to keep it cooler than body temp. The breeding male
is often housed outside and semen quality he is producing is
sensitive to hot weather. When outside temp approaches 102°F –
normal body temp – male fertility can suffer