Cobalt and vitamin B12 in diets for commercial laying hens on the second cycle of production

Abstract

The supplementation of cobalt and vitamin B 12 in diets for commercial laying hens on the second production cycle was studied. Four hundred and eighty light commercial laying hens, Lohmann LSL, were used at initial phase of forced molting laying period. The trial was conducted in a randomized design. The plots were the treatments which were constituted by combination of five cobalt levels (0.00; 0.30; 0.60; 0.90 and 1.20ppm) and two vitamin B 12 levels (without and with 10µ/kg) , and the split-plots were four periods (21, 42, 63 and 84 days) during the second period of production, with 4 repetitions and 12 hens per experimental unit. Food and water were provided ad libitum and eggs were collected twice daily. Performance and egg quality parameters were evaluated. At the end of experimental period, two layers from each treatment were slaughtered, and liver and blood samples were taken for analysis. Performance and egg quality were not different (p>0.05) among cobalt supplementation levels, although egg damage data were different (p<0.05). Supplementation with vitamin B 12 decreased egg weight. No influence of cobalt or vitamin B 12 supplementation was seen on the concentration of cobalt in the liver and yolk as well as on blood analysis (hematrocrit, hemoglobin, erythrocytes, and leukocytes). The results revealed that vitamin B 12 supplementation was important for commercial laying hens on the second cycle of production, but not cobalt supplementation.

Laying Performance, Fat Digestibility and Liver Condition of Laying Hens Supplemented With Vitamin B12 or Biotin and/ or Bile Acids in Diet

“…Unlike the obtained results, earlier studies examined the effects of vitamin B12 (20,21), concluded that it had no clear effect on FI of commercial laying hens, while increased FI with Halle and Ebrahem (22). Improvement of FCR with vitamin B12 supplementation in the present study is in line with Halle and Ebrahem (22), while inconsistent with Kato et al (20).…”

Effect of Dietary Humic Preparations on the Content of Trace Elements in Hens’ Eggs

“…and other authors [21,22] in egg content from hens kept in free range system, reported the average cobalt content in the range 0.0061 -0.01 mg/kg d.m. It was found that the supplementation of cobalt salts or vitamin B 12 only slightly increased the level of Co in egg content [20] . In shells of hens eggs (without eggshell membranes), the content of Co was found to be in the range 0.70-0.82 mg/kg [11] .…”

“…Richards [4] reported the content of Co in egg yolk on the level 0.0084 and in egg albumen only 0.012 mg/kg fresh mass. Kato et al [20] determined the concentration in egg content as 0.0877 mg/kg d.m. and other authors [21,22] in egg content from hens kept in free range system, reported the average cobalt content in the range 0.0061 -0.01 mg/kg d.m.…”

Concentrations of selected metals in chicken eggs from commercial farms in Southern Nigeria

“…Richards (1997) reported the content of Co in egg yolk and albumen as 0.0084 and 0.012 mg g À1 , respectively. Kato et al (2003) reported Co contents of 0.0877 mg g À1 in eggs. Cobalt concentrations ranging from 0.0015 to 0.166 mg g À1 have been reported in eggs from Poland (Dobrzanski et al 2007).…”