Productive performance of broilers at the final stage of breeding submitted to different levels of metabolizable energy in different thermal environments
Laen...
Kuupäev
2018
Kättesaadav alates
Autorid
Oliveira, K.P.
Ferreira, C.F.S.
Tinoco, I.F.F.
Andrade, R.R.
Barbari, M.
Cruz, V.M.F.
Baptista, F.J.F.
Vieira, M.F.A.
Conti, L.
Rossi, G.
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Abstrakt
The Brazilian poultry industry is an activity in constant development due to the high
indices of productive efficiency. The accelerated evolution of poultry production has allowed
to
obtain early and very efficient broilers able to convert different foods into animal protein.
However, due to this intensive breeding system, a series of metabolic and management problems
appeared, with emphasis on thermal stress. The objective of this
work was to evaluate the
physiological responses of broiler chickens in the final stage of breeding (21 to 42 days of life),
submitted to two thermal conditions, one representative of the thermoneutrality situation (T1) and
one giving a situation of cyclic
stress by heat (T2). For each experimental thermal condition, the
birds were submitted to different levels of metabolizable energy of 3,050, 3,125, 3,200,
3,275
kcal
kg
-
1
. At 28, 35 and 42 days, the birds and the feed leftovers were weighed to measure
the
performance variables: CR (feed intake), GP (weight gain) and CA (feed conversion),
viability of the rearing (Vb), productive efficiency index (PEI).
As conclusions, the GP was 13.6% higher for the birds maintained at the thermoneutrality
situation T1. Th
e PEI was 32.5% higher for the birds maintained in T1 condition, when compared
to those kept in T2. However, both in thermoneutral and in heat stress conditions, the increase in
the level of metabolizable energy in the diet did not influence the performanc
e and the productive
efficiency index of broiler chickens aged between 21 and 42 days of age.
Kirjeldus
Article
Märksõnad
broilers, feed, metabolizable energy, productivity, hermal stress, articles