Eggshell Quality as Influenced by Sodium Bicarbonate, Calcium Source, and Photoperiod

Abstract

The effects of Ca source (limestone or a mixture of one-third limestone and two-thirds oyster shell), NaHCO3 (0 or .5%) and feeding photoperiod (16 or 24 hr) were studied in a 16-week experiment involving 240 Hy-Line W-36 Leghorn hens, 25 weeks of age. Neither egg production (percent hen-day and egg mass, kg egg/bird per 16 weeks) nor feed conversion ratio (kg feed per kg egg) were significantly (P greater than .05) affected by dietary treatment or photoperiod. However, extending the photoperiod to 24 hr significantly (P less than .05) increased feed consumption with a consequent increase in egg weight (P less than .01). Feeding oyster shell in combination with limestone significantly (P less than .05) improved specific gravity of eggs, whereas dietary NaHCO3 significantly (P less than .01) improved elasticity of the egg shell as measured by deformation. Eggshell quality was improved by increasing the photoperiod to 24 hr and was most pronounced when hens were fed diets supplemented with .5% NaHCO3 and limestone as the only source of Ca.

Performance and egg quality of aged laying hens fed diets supplemented with meat and bone meal or oyster shell meal

“…In contrast to our findings, former studies concerning OSM supplementation showed beneficial effects on eggshell breakage strength (Watkins et al, 1977;Brister et al, 1981;Makled & Charles, 1987;Proudfoot & Hulan, 1987;Guinotte & Nys, 1991;Grizzle et al, 1992;Ahmad & Balander, 2004). The results of the present study further support some recent investigations by Lichovnikova (2007) and Safaa et al (2008) who observed that oyster shell is less soluble than fine or coarse limestone, contradicting conventional theories of higher digestibility and retention associated with oyster shell by some researchers (Scott et al, 1971;Roland, 1988).…”

“…Some previous scientific publications also confirmed that laying hens did not benefit from either MBM (Oruseibio, 1995;Bozkurt et al, 2004) or OSM (Brister et al, 1981;Makled & Charles, 1987;Grizzle et al, 1992;De Faria et al, 2000;Safaa et al, 2008) supplementation of the diet.…”

“…It was hypothesized that the reason for this was that the larger particles of oyster shells took longer to digest because they remained in the gizzard and were slowly dissolved over a prolonged period (Scott et al, 1971). Confirming this hypothesis, a great deal of previous scientific work reported that oyster shell meal (OSM) supplementation to the layer hen diet significantly improved egg breaking strength (Hauser & Norris, 1946;Watkins et al, 1977;Keshevarz & McCormick, 1991) and egg specific gravity (Makled & Charles, 1987;Grizzle et al, 1992) when compared to limestone.…”

Laying Performance and Egg Quality of Hens Supplemented with Humate and Sodium Bicarbonate during the Late Laying Period

“…Alteration in nutrient partitioning (Stepchenko et al, 1991;Parks, 1998) could be associated with increased egg production in hens Supplemented with humate. Makled and Charles (1987) reported that 0.5% NaHCO,, …”

Interaction between oviposition time, age, and environmental temperature and egg quality traits in laying hens and broiler breeders

“…by Roberts (2004), Franco-Jimenez et al (2007, and Oguntunji and Alabi (2010). Poorer egg shell quality in hens under heat stress was shown to be the result of hyperventilation and a lack of bicarbonate ions (Lorcher and Hodges, 1969;Makled and Charles, 1987). The highest specific gravity exhibited the eggs from young laying hens collected in the afternoon at 20°C (1.128) and the lowest the eggs laid in the afternoon by old broiler breeders (1.050); this four-way interaction proved to be significant (P = 0.050).…”