Banca de DEFESA: ELTON FRANCISCO DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ELTON FRANCISCO DE OLIVEIRA
DATE: 21/02/2025
TIME: 09:00
LOCAL: Departamento de Zootecnia
TITLE:

ESTIMATE OF METAL AMINO ACID  ZINCO FOR LAYING HENS IN THE POST-PEAK PERIOD

KEY WORDS:

bone quality; complexed minerals; hemogram; micromineral; performance.

PAGES: 52
BIG AREA: Ciências Agrárias
AREA: Zootecnia
SUBÁREA: Nutrição e Alimentação Animal
SPECIALTY: Exigências Nutricionais dos Animais
SUMMARY:

Zinc is an essential mineral for laying hens and, compared to inorganic sources, its amino acidcomplexed form provides better absorption by the animal. However, determining the optimal supplementation levels is crucial. Therefore, this study aimed to estimate the requirement of amino acidcomplexed zinc (ZnCAA) for commercial laying hens. A total of 336 laying hens aged 55 weeks were used, distributed in a completely randomized design. The supplementation levels were 0, 5, 15, 25, 40, 60, and 80 mg/kg of ZnCAA. To determine the optimal estimate, evaluations were conducted on productive performance, egg quality, blood cell analysis, and bone quality. The data were tested for homogeneity of variances and normality of residuals, followed by regression analysis to estimate the optimal zinc intake. The Broken Line model provided the best fit, describing the relationship between zinc deposition and intake. For performance, there was no significant effect on egg weight, feed intake, feed conversion. However, significant effects were observed for egg mass (P=0.010) and production (P=0.001), with estimates of 2.715 and 6.301 mg/bird/day, respectively. For egg quality, there was a significant effect on albumen height (P=0.053), with an estimate corresponding to 4.8 mg/bird/day. For proximal densitometry, a quadratic effect was observed (P=0.002), and for medial densitometry, a significant effect was found (P=0.026), with an estimate of 1.8 mg/bird/day. To hemogram, there were significant effects on hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin concentration, with supplementation levels of 3.4, 2.9, and 2.3 mg/bird/day, respectively. Based on the results obtained, it is recommended to supplement with 3.4 mg/bird/day of dietary for light commercial laying hens in the post-peak phase, which corresponds to 32.3 mg/kg of feed, aiming to ensure satisfactory productive performance, hematological homeostasis, and bone quality.

COMMITTEE MEMBERS:
Presidente - CARLOS BOA VIAGEM RABELLO
Externa à Instituição - CLAUDIA DA COSTA LOPES - UFRN
Externo à Instituição - MARCOS JOSÉ BATISTA DOS SANTOS