The Combined Effects of Dietary Lysine and Total Sulfur Amino Acid Level on Egg Production Parameters and Egg Components in Dekalb Delta Laying Hens

Abstract

Dekalb Delta hens were randomly assigned to one of eight dietary treatment groups. Two intakes of lysine (860 and 959 mg/hen per day) and 4 intakes of TSAA (635, 689, 811, 877 mg/hen per day) were combined in a 2 x 4 factorial treatment arrangement and fed from 20 to 43 wks of age. A phase feeding regimen was implemented at 43 wk with lysine intake lowered to 715 or 816 mg/hen per day and TSAA to 578, 607, 699, or 779 mg/hen per day. Cage was the experimental unit (5 hens/cage), and dietary treatments were replicated 8 times. Egg production (EP) and feed consumption were not affected by dietary treatments. Feed efficiency improved linearly by increasing TSAA intake during phase I only. Hen weight gain was improved (P < or = 0.03) by increased dietary lysine (94.2 vs. 135.2 g weight gain/hen). During phase I, hen weight gain was affected quadratically (P < or = 0.02) by TSAA. Increasing TSAA intake up to 689 mg/hen per day increased hen weight gain, but gain decreased at the highest intake. Egg weights (EW) increased (P < or = 0.02) from 59.02 to 60.21 g with increased lysine intake. Increasing lysine intake increased wet and dry albumen percentage, whereas dry yolk percentage decreased with increasing lysine. Total sulfur amino acid intake affected wet yolk, dry yolk, and solids in a quadratic trend, with hens fed 811 and 699 mg/d producing eggs with the greatest yolk solids. Wet and dry shell percentages were not affected by lysine or TSAA, and specific gravity decreased linearly during phase II and overall, with increased dietary TSAA. In conclusion, the dietary lysine at 959 and 816 mg/hen per day for phases I and II, respectively, optimized EW and feed efficiency. Because EP was not affected by dietary lysine, the dietary level for optimizing EP is closer to 860 and 715 mg/hen per day for phases I and II, respectively. Dietary TSAA level for maximum EP and feed efficiency was near 811 and 699 mg/hen per day but for EW may be closer to 877 and 779 mg/hen per day for phases I and II, respectively.

Performance and egg quality of laying hens fed with dietary levels of digestible lysine and threonine

“…Therefore, this result can be associated to the amino acid imbalance with the decreasing feed intake that might have negatively affected the intake of nutrients (calcium, phosphorus, vitamins, trace minerals and others) essential for egg shell formation. In contrast to the present result, Liu et al (2005) and Novak et al (2004) found no differences in egg shell percentage with increasing lysine levels in the diet.…”

Níveis de metionina + cistina digestível para poedeiras leves no período de 42 a 58 semanas de idade

“…De acordo com Novak et al (2004), a síntese de proteína no tecido do magno pode ser afetada por mudanças na concentração de aminoácidos no sangue. Porém, o aumento da ingestão de metionina + cistina digestível no presente estudo não aumentou a porcentagem de albúmen (P>0,05), embora tenha aumentado o peso médio do albúmen, que variou de 35,4 a 38, 5 g A redução na porcentagem de casca pode ser devido ao aumento verificado no tamanho dos ovos, sem aumento na produção da casca.…”

“…Resultados semelhantes ao do presente estudo foram obtidos por Novak et al (2004) ao trabalharem com poedeiras leves de 44 a 63 semanas de idade, com consumos de aminoácidos sulfurosos que variaram de 615 a 833 mg/ave/ dia, verificando efeito significativo para porcentagem de gema e não significativo para porcentagem de albúmen. Por outro lado, Pavan et al (2005), trabalhando poedeiras semipesadas e consumos que variaram de 661 a 823 mg/ave/ dia de aminoácidos sulfurosos, constataram efeito significativo tanto para percentual de gema quanto para percentual de albúmen.…”

Exigência de lisina digestível para poedeiras semipesadas de 50 a 66 semanas de idade

“…Zootec., v.67, n.6, p.1675-1683, 2015 Prochaska et al (1996) avaliaram a influência da ingestão de rações com três níveis de lisina (677; 1.154 e 1.613mg/ave/dia) sobre os componentes dos ovos (sólidos do albúmen, sólidos de gema, proteína do albúmen e proteína da gema) de poedeiras de 42 a 64 semanas de idade e detectaram efeito significativo nas variáveis avaliadas, de modo que o maior nível de ingestão de lisina promoveu a maior resposta desses componentes. Novak et al (2004) também observaram aumento significativo no percentual de albúmen dos ovos de poedeiras alimentadas com 959mg de lisina total/ave/dia em comparação aos ovos das aves alimentas com 860mg de lisina total/ave/dia, e esse aumento se refletiu diretamente no percentual de sólidos do albúmen.…”