Energy and protein dilution in broiler breeder pullet diets reduced offspring body weight and yield.

The objective of the current research was to evaluate transgenerational effects of maternal dietary energy and protein on growth, efficiency, and yield of broiler offspring. A factorial arrangement of treatments consisting of high and low ME and CP levels fed during the rearing and laying phases was used. The study was a final 2 × 2 × 2 × 2 factorial arrangement of treatments, including broiler sex. Ross 708 broiler breeder pullets (n = 933) were fed diets containing 2,736 (HEREAR) or 2,528 kcal/kg ME (LEREAR) with either 15.3% (HPREAR) or 13.7% CP (LPREAR). From 25 wk, dams were fed a 15% CP laying diet containing 2,900 (HELAY) or 2,800 kcal/kg ME (LELAY). Following artificial insemination of the dams at 35 wk, eggs were collected for 1 wk, incubated, and pedigree hatched to preserve maternal identity. Broiler offspring were placed sex-separately into 32 pens, according to laying phase maternal treatments, with rearing maternal treatments nested within pens. Individual BW and pen level feed intake were recorded weekly. Broilers were processed at 40 d of age to evaluate yield. Maternal diet effects on offspring BW were sex dependent and transient. Female LPREAR × LELAY broilers had lower pectoralis major and carcass yield than HPREAR × LELAY females. Male HPREAR × HELAY broilers had increased breast yield (19.8%) compared with 18.4% in HPREAR × LELAY broilers. Carcass yield was lower in LEREAR × HPREAR broilers (63.7%) compared with HEREAR × HPREAR broilers (64.9%). LEREAR × HPREAR dams had the lowest ME to CP ratio (E: P) diets and highest rearing phase CP intake. Maternal diet did not influence offspring FCR. The most consistent contributor to increased BW was higher maternal dietary CP and ME during rearing. Low ME maternal laying phase diets increased BW of male offspring more consistently than of female offspring. Maternal nutrition also influenced broiler yield, and is thus economically important. Energy and protein dilution in broiler breeder pullet diets may have detrimental effects on offspring performance.

Effect of maternal dietary energy and protein on live performance and yield dynamics of broiler progeny from young breeders.

The objective of this research was to evaluate effects of female broiler breeder dietary ME and CP during rearing and dietary ME during early lay on broiler offspring performance and carcass yield dynamics. A factorial arrangement of treatments, with 2 ME levels, and 2 balanced protein levels from 3 to 24 wk, followed by 2 ME levels in the lay diets, and in the broilers, 2 sexes. A total of 1,635 broilers were housed in 32 pens, with 8 replicate pens according to maternal laying diet and sex. Maternal pullet diets were nested within pen (n = 9 to 14, depending on hatch rate). The broilers originated from 384 Ross 708 hens, which had been fed diets containing high (2,736 kcal/kg, HEREAR) or low ME (2,528 kcal/kg, LEREAR) combined with either high (15.3%, HPREAR) or low balanced protein (13.7% CP, LPREAR). Equal numbers of hens from each pullet treatment were then fed either a high (2,900 kcal/kg, HELAY) or low ME diet (2,800 kcal/kg, LELAY) containing 15% CP. Broilers were hatched from eggs collected at 28 wk of age, and fed identical diets. Broilers were individually weighed weekly. Serial dissections were conducted to evaluate yield breast muscle and abdominal fatpad dynamics. At 39 d, 180 broilers were processed to measure carcass yield. Female progeny of hens with the lowest CP intake during rearing (HEREAR × LPREAR) were lighter from 22 to 36 d of age than female offspring from hens that consumed more CP as pullets. We predicted the heaviest female progeny would result from an ME:CP ratio of 18.25 kcal/g in maternal pullet diets (P = 0.0063). Broiler breast yield increased when maternal EM:CP ratio increased after switching from pullet to laying diets. Hens fed HEREAR were fatter and had fatter progeny than LEREAR. Maternal diet, even during the pullet phase, influenced progeny growth and yield.

Avaliação de diferentes vias vacinais para vacinação contra o vírus da doença de Newcastle em aves de fundo de quintal / Assessment of different vaccination approaches against Newcastle disease virus in domestic backyard poultry

Foram avaliadas três vias de aplicação vacinal contra o vírus da doença de Newcastle em aves de criatório de fundo de quintal (AFQ) jovens e adultas. Um total de 135 AFQ foram distribuídas em tratamentos distintos de acordo com a via vacinal: via ocular (VO), água de bebida (VAB) e alimentar (VA). Cada tratamento foi representado por 40 aves (20 jovens e 20 adultas) e utilizou-se um grupo-controle de 15 aves não vacinadas. O programa de vacinação estabelecido constou de uma primovacinação e dois reforços vacinais, utilizando-se a cepa La Sota. Para aves jovens, os títulos obtidos pelas VO e VAB não diferiram aos 15, 45 e 140 dias, mas houve diferenças nos títulos das aves vacinadas pela VA. Nas aves adultas, a vacinação pela VO apresentou resultados mais elevados que as vacinações pelas VAB e VA na primeira resposta, aos 15 dias. Aos 45 dias, os títulos obtidos pela VAB foram mais baixos que os obtidos pela VO, e, aos 140 dias, não houve diferença entre as três vias avaliadas. Concluiu-se que as vacinações pelas VO e VAB constituem alternativas eficazes para vacinação de AFQ jovens e adultas.

Three ways of vaccination against Newcastle Disease Virus (NDV) were evaluated in young and adults domestic backyard poultry (DBP). A total of 135 DBP was submitted to three different administration routes of ND vaccine: eye-drop, drinking water, and feed. Each treatment consisted of 40 birds (20 young and 20 adult) and a control group of 15 unvaccinated birds. The treatment consisted of a first vaccination and two boosters, using La Sota strain. For young birds, the eye-drop and drinking water vaccinations presented no differences at 15, 45, and 140 days, differing from the titers obtained by birds treated by feed vaccination method. In the adult birds, the eye-drop administration presented higher titers than by drinking water and feed approaches in the first response to the vaccination at 15 days. At 45 days, the results obtained by the drinking water had lower titers than those from the eye-drop. The three vaccination methods presented no difference at 140 days. In conclusion, the vaccination by eye-drop and drinking water methods constituted an efficient alternative of vaccination for adult and young DBP against Newcastle virus.