35 LOHMANN TIERZUCHT › MANAGEMENT GUIDE 35 GENERAL RECOMMENDATIONS can’t be dissolved by application of acids. Sometimes coarse limestone or even oys- ter shells are described as ‘grit’ as well or as ‘grit limestone’ – which is not LTZ under- standing. Coarse limestone or as ever it can be described can easily being dissolved by adding of acids. This idea is even a very practical test (beside a chemical analysis) if a layer feed might have roughly enough limestone in order to supply the laying hen with sufficient amount of calcium. Table 7: Amount and Granulation of Grit Dependent on Age Week 1–2 once a week 1g /bird (size 1 – 2 mm) Week 3–8 once a week 2g/bird (size 3–4 mm) From week9 once a month 3g/bird (size 4 – 6 mm) Litter (Non Cage Housing) Only use shavings from untreated wood in order to avoid poisoning and residues in the egg. Provide sufficient ventilation to ensure good litter condition and remove wet litter, if necessary. Egg Quality and Egg Collection LOHMANN BROWN-CLASSIC layers produce eggs of excellent quality. To preserve the quality, the following points should be observed: › Collect eggs at least once a day. › Store eggs at temperatures between 5 °C and 10 °C with a relative humidity of between 80 – 85%. Storing at higher temperatures and lower humidity leads to rapid loss of weight and impairs the quality of the egg white due to an increase in gas exchange. Nests (Non Cage Housing) The quality of nests is also a factor which affects egg quality. Renew the litter in litter- type nests regularly and keep them clean. Provide individual nests at a rate of one nest for 4 hens. Collect floor eggs frequently to keep their rate as low as possible. In addition to sufficient nesting space in fam- ily type nests, the following factors are im- portant for a  low rate of floor eggs: › Clean, dry litter or soft nest lining › Easy access › Even distribution of the nests within the barn › Only one type of nest in the barn For optimum egg quality, rollaway nests in combination with slats are better than litter- type nests or family type nests.