The breeding of Japanese quail as a heterotrophic link in the closed e
cosystem should involve recycling of biogenic substances of quail drop
pings, among other things by their re-feeding. Besides their feeding i
n dried form, one of the alternatives is their cultivation by larvae o
f the housefly (Musca domestica L.). Numerous papers have shown that d
ried quail droppings (cultivated or uncultivated) can be administered
up to the amount of 20% in feed mixtures without any substantial effec
t on quail performance. In the present paper investigations are descri
bed aimed at determining the productive effect of feeding dried uncult
ivated and cultivated quail droppings (together with pupae) in feed mi
xes with animal-protein feeds as well as vegetable-protein feeds to Ja
panese quail (Tabs. I to II). The trial lasted from 2 to 26 weeks of q
uail age nursing period 2nd to 6th week, laying period 7th to 26th wee
k of age. Tab. IV shows the results obtained in the nursing period. Ad
ministration of booth types of droppings postponed sexual maturity by
1 to 3 days when feed mixes with animal proteins were fed and by 2 to
6 days while mixes with vegetable proteins were fed (Tab.V). Droppings
feeding in mixes with animal proteins did not significantly influence
egg production and weight (P > 0.05), while administration of mixes w
ith vegetable proteins decreased these indicators only insignificantly
(by 2.9% and 3.8%, resp.) in uncultivated droppings; in cultivated dr
oppings the decrease was significant (by 4.9% and 6.6%, resp.). The ba
se mixture with vegetable proteins did not affect laying intensity, bu
t egg weight decreased by 6.6% (P < 0.05). Administration of droppings
in the mix with animal proteins significantly decreased only the weig
ht (P < 0.05) and percentage of yolk in the case of uncultivated dropp
ings (Tab. VI), while in the mix with vegetable proteins which themsel
ves decreased the weight of egg, albumen and yolk the feeding of culti
vated droppings did not decrease albumen weight. Droppings feeding how
ever decreased egg shape index in both types of feed mixes (P < 0.05).
The quail with dietary droppings consumed by 10.4 to 12.8% more of al
l feed but by 10.2 to 11.7% less of grains (P < 0.01) regardless of pr
otein composition. Differences in feed conversion were proportionately
worse to a reduction in egg weight (by 12.9% and 14.9% in all feed an
d by 8.3% and 9.7% in grains with animal proteins; by 18.2% and 21.5%
in all feed and by 3.5% and 5.6% in grains with vegetable proteins). T
he ratio of fresh droppings produced to ingested feed increased from 0
.55 to 0.60 and 0.61 for mixes with animal proteins, and from 0.59 to
0.62 and 0.63 in mixes with vegetable proteins, applying to the groups
with dietary droppings (Tab. VII). In uncultivated droppings, a trend
of an increase in crude protein content and of a decrease in digestib
le crude protein in dried droppings was observed for mixes with animal
proteins, while in cultivated droppings a decrease in both indicators
was observed for mixes with vegetable proteins. There was not any sig
nificant difference in the live weight of quail, except a weight incre
ase in group III TKZ. Neither was there a difference in the dressing p
ercentage and mortality of quail. Dried quail droppings, both uncultiv
ated and cultivated by housefly larvae, can be fed in mixes with anima
l proteins without any significant decrease in performance up to the a
mount of 20%. Feeding in mixes with vegetable proteins decreases egg w
eight while the feeding of cultivated droppings also lowers egg produc
tion.