Enrichment in vitamins

Vitamin concentration in hen feed is the most important factor in determining vitamin content in the egg. This is particularly true for fat-soluble vitamins. The lipid components of the egg, including fat-soluble vitamins, are only present in the yolk. During the last 10 days before hen ovulation, the lipids of dietary origin are absorbed and deposited in the yolk in the last phase of its formation. As the fat-soluble vitamin concentration of the feed increases, so does the vitamin content of the egg yolk. The most relevant data related to egg vitamin enrichment through nutrition are presented in this chapter, with special attention paid to vitamins E, A, and D. In particular the vitamin enrichment level reached in the egg and the implications on daily vitamin intake and consequently on consumer health are discussed

Teores de ácidos graxos em ovos comerciais convencionais e modificados com ômega-3 Fatty acids levels in conventional and designer omega-3 commercial eggs

Objetivou-se comparar os teores de ácidos graxos em ovos comerciais convencionais e em ovos modificados com ômega-3. Foram utilizadas 864 poedeiras da linhagem Isa Brown aleatoriamente distribuídas em dois grupos, de modo que cada gaiola com quatro aves foi considerada uma repetição, totalizando 216 repetições. No grupo para produção de ovos convencionais, as aves foram alimentadas durante toda a vida produtiva com ração à base de milho e farelo de soja, enquanto, no grupo para produção de ovos modificados, foram alimentadas, a partir da 22ª semana de idade, com ração contendo 1,5% de substrato de algas marinhas e 1,8% de óleo de peixe. Foram coletados, aleatoriamente, 180 ovos de cada grupo de poedeira (totalizando 360 ovos), que foram distribuídos em delineamento de blocos ao acaso, considerando cada ovo uma repetição. Os ovos modificados com ômega-3 apresentaram menores de índice de gema, mas não diferiram dos ovos convencionais quanto aos demais parâmetros de qualidade. As médias de ácidos graxos poliinsaturados ômega-3 e de ácidos graxos monoinsaturados foram mais altas nos ovos modificados. As relações entre ácidos graxos poliinsaturados e saturados e entre ômega-6 e ômega-3 nos ovos modificados foram próximas ao ideal estimado para alimentação humana. As médias de ácidos graxos poliinsaturados da série ômega-6 e de ácidos graxos saturados nos ovos convencionais foram significativamente maiores que dos ovos modificados com ômega-3.<br>The objective of this work was to compare the levels of fatty acids between conventional commercial eggs and designer omega-3 eggs. It was used 864 Isa Brown line laying hens randomly distributed in two groups, so each cage with four birds was considered a replicate, totalizing 216 repetitions. In the group for production of conventional eggs, birds were fed corn- and soybean-based rations during the entire productive life while in the group for production of designer eggs, they were fed, from the 22nd week of age, rations with 1.5% of marine algae substrate and 1.8% fish oil. A total of 180 eggs was randomly collected from each group of the laying hens (totalizing 360 eggs), which were distributed in a randomized block design, considering each egg a replicate. Designer omega-3 eggs showed the lowest yolk index, but they did not differ from the conventional eggs regarded to the other parameters of quality. Means of omega-3 polyunsaturated fatty acids and monounsaturated fatty acids were higher for designer eggs. The relationships between polyunsaturated and saturated fatty acids and among omega-6 and omega-3 in designer eggs were close to the ideal estimated for human consumption. Means of the polyunsaturated fatty acids from the omega-6 series and of saturated fatty acids were significantly higher than omega-3 designer eggs

Effects of different dietary vitamin combinations on the egg quality and vitamin deposition in the whole egg of laying hens

The experiment was conducted to evaluate the effects of different dietary vitamin combinations on the egg quality and vitamin concentrations in the eggs of commercial laying hens. A total of 1,800 25-week-old Lohman pink-shell hens were randomly assigned to four dietary vitamin treatments as follows: NRC(1994) level, NRC (1994) level with Hy.D® (25-hydroxy-cholecalciferol), Local level (current average industry level in China) and OVN® level (optimum vitamin nutrition level), with 10 replicates per treatment and 45 layers per replicate. Hens were housed in commercial laying cages with three birds per cage and given ad libitum access to feed. Results showed the hens that received the fortified vitamin levels in the OVN® treatment had a significantly (p<0.05) lower number of cracked (.47%) and dirty eggs (.27%), and increased egg deposition of vitamin B12, folic acid, vitamin A, vitamin D, 25-OH-D3, vitamin E, vitamin B1, biotin and pantothenate (p<0.05). Treatments had no significant effect on egg-shape index, egg specific gravity, Haugh units and eggshell thickness. Hens fed the NRC-Hy.D® combination also experienced a significant decrease in cracked and dirty eggs (.70% and .44%, respectively) and an increased deposition of 25-OH-D3 in comparison with the NRC treatment. Results of the present study suggest that that the Local treatment was able to improve egg quality parameters of laying hens, but resulted in more cracked and dirty eggs. OVN® reduced the number of cracked eggs and dirty eggs, and improved the deposition of several vitamins in eggs. With the addition of Hy.D®, eggshell strength and 25-OH-D3 deposition in eggs were also improved, and cracked and dirty egg rates declined