Assessment of postcrumble addition of limestone and calcium-specific appetite in broilers during the starter phase.

A study was done to determine whether broilers can regulate Ca intake when limestone is provided separately or mixed with a crumbled feed of variable Ca and P content, and the influence of this on performance and apparent ileal digestibility (AID) of Ca and P (AIDP). Twelve crumbled diets were fed from 10 to 20 d of age (8 replicates, 8 broilers/replicate). Diets A to D contained 0.28% nonphytate P (nPP) and 0.27, 0.51, 0.77, and 1.02% Ca, respectively. Diets E to H contained 0.48% nPP and 0.41, 0.51, 0.77, and 1.02% Ca, respectively. A large particle size limestone was mixed manually to the crumbled diet on a daily basis to achieve 1.02% total Ca in diets A to H. Diets I to L had the same Ca and nPP as diets A to D, but limestone was provided in a separate feeder to assess spatial importance of limestone supply. Limestone consumption, provided in a separate feeder, decreased as Ca concentration increased in the crumble diet (P < 0.05). Calcium intake increased as Ca concentration in crumbled diets increased (P < 0.05). Increased tibia ash and decreased AIDP were observed as Ca intake increased (P < 0.05). When limestone was added to diets containing 0.28% nPP postcrumble, Ca intake (6.38 g/bird), tibia ash (717 mg/bone), and AIDP (39.78%) were not affected by crumbled diet Ca concentration or consumed Ca. Broilers fed diets containing 0.48% nPP and limestone mixed with the crumble, Ca intake changed (5.96, 6.93, 6.59, and 6.04 g/bird for crumble diet with 0.41, 0.51, 0.77, and 1.02% Ca, respectively). Increasing Ca concentration in the crumble from 0.41 to 1.02% resulted in greater tibia ash (875 mg/bone) but lower AIDP (P < 0.05), although Ca intake was similar. In conclusion, when large particle size limestone was provided ad libitum, the ability of broilers to select for Ca was not sufficient to meet their requirement when crumble Ca was less than 0.77%. The AIDP was highest in birds fed the 0.27% Ca concentration diet.

Meat quality of Argentinean "Camperos" chicken enhanced in omega-3 and omega-9 fatty acids.

Five diets were assessed with the aim of increasing oleic fatty acid and omega-3 polyunsaturated fatty acid content in 'campero' poultry meat and evaluating their influence on sensory attributes. Animals from treatment 1 (T1) were confined and fed with corn/soybean diet; in T2, animals were fed with a corn/soybean mix with free access to pasture; T3 diet had high oleic sunflower seeds (HOSS) and linseeds with access to pasture; T4 diet was similar to T2 with free access to chicory instead of pasture and T5 diet was similar to T3 with free access to chicory instead of pasture. Linseeds and HOSS supplementation significantly increased the fatty acids profile, regardless of forage supply. T3 MUFA content was significantly higher than in the other treatments. Due to the high presence of omega-3 PUFA in linseeds and HOSS treatments (T3 and T5), meat omega-6/omega-3 ratio decreased from 9 to 4. The presence of off-flavours was not influenced by diets but there was an interaction between portion and storage conditions. 'Poultry meat' aroma was only influenced by the storage conditions, being slight after 4 months of freezing, while presence of off-aromas was affected by diets. We conclude that it is possible to produce 'campero' poultry meat with enhanced omega-3 and omega-9 content and a low omega-6/omega-3 ratio using diets based on linseed and HOSS, without any important change in sensory properties.