Rit Landbúnaðardeildar : B-flokkur - 01.09.1961, Side 109

107
Verðgildi afurðaaukningarinnar er funclið með því að reikna með verði því,
sem bændur áttu að fá fyrir sauðfjárafurðir 1959 samkvæmt verðlagsgrund-
velli það ár, sjá bls. 104. Ennfremur er tekið tillit til þeirra breytinga, sem
verða á gæðamati fallanna í tilraununum, við útreikning á verðmæti afurða-
aukningarinnar. Verðmunur á I. og III. gæðaflokki er reiknaður á kr. 1.58
eins og verðlagsgrundvöllurinn gerir ráð fyrir, og ennfremur er verðgildi I.
gæðaflokks talið kr. 0.50 hærra en II. gæðaflokks, þótt ekki sé gert ráð fyrir
]íví í verðlagsgrundvelli.
SUMMAR Y.
Owing to the extremely wet and cold climate in late autumn in Iceland lambs not in-
tended for flock replacements are slaughtered. This slaughter at weaning, 120 to 130
days of age, occurs in late September and early October in whatever condition the lambs are
in when gathered from tlie common grazings. As a rule the majority of the lambs are in
good enough condition to give first quality carcasses at weaning. However, many twins as
well as singles from the poorer pastures are lacking in finish and general development ne-
cessary to grade better than second or third class at the stage.
In recent years experiments have been carried out to determine whether poorly developed
Icelandic lambs can be successfully and economically fattened on aftermath, young grass or
forage crops, in a period of 3 to 7 weeks prior to slaughter so that they can be disposed off
before winter sets in.
I. In this report 15 experiments on fattening o£ lambs for slaughter on cultivated land
are described in l’arts I to XV. In each experiment two to six equalized groups of 20 lambs
were used, except in experiment no. VII where each group consisted of 22 lambs. These ex.
periments may be divided in two main series.
a: A series of 4 experiments where comparison was made between grazing unweaned lambs
on aftermath versus natural hill pasture in autumn. These experiments are described in
Parts III, IV, V and VII.
b: A series of 11 experiments where comparison was made between grazing unweaned
lambs on natural hill pasture on the one hand and weaned lambs on aftermath, young grass,
or various forage crops on the other hand. In all these experiments a control group of lambs
was killed when the experiment started for comparison of development at that stage. This
enabled onc to study the actual gain in weight of carcass and offal as well as changes in car-
cass quality in cach group during the experimental period.
In experiments No. I and II coinparison was made between autumn grazing on aftermath
and hill pasture. In experiment No. VI comparison was made between grazing on young grass
and hill pasture. In experiments No. VIII, XI, XII, XIII and XV comparison was made
between grazing on marrowstem kale and hill pasture and in cxpcriments No. IX, X and
XIV comparisons were made bctween grazing on various forage crops and hill pasture.
Further in experiments No. XIV and XV the effect of stilbestrol implanted subcutaneously
in the ear was studied on lambs grazing on marrowstem kale.
II. a: In experiments No. III, IV, V and VII the lambs, which grazed on aftermath killed
out on the average better than those on hill pasture after an average experimental period of
25.5 days.