Layer pullets are not frequently in the center of discussions among nutritionists, yet a successful rearing program is the key for better life-long performance. An early-maturing pullet might start producing eggs sooner, but she will keep producing smaller and fewer eggs during her lifetime, making waiting for the right time and condition the key for any successful rearing program. Below are six simple guidelines that aim in producing a better pullet at the time of placement in the layer house.
1. Body weight at maturity is key
Frame size, shank length and even body composition are no longer considered as important as body weight for age when it comes to evaluating the condition of modern pullets. White-egg layers should attain an average of 1,250 grams body weight at 18 weeks of age. Brown-egg layers, being heavier, should be about 1,500 grams at similar age. If the pullets are much heavier, not only have they consumed more feed than necessary, but they also keep eating more due to higher maintenance needs throughout their lifetime. In contrast, light-for-age pullets might be more economical to raise, but any early savings are lost many times over later on as these pullets fail to keep at peak productivity for long.
2. Feed according to actual body weight
All genetic stock companies have guidelines for optimum body weight for their strains. These tables and graphs are usually followed by timelines and feeding instructions that allocate certain amounts of feed during each week as pullets grow. All such information should be used as the basis to form any and all farm-specific nutrition programs. Actual numbers should reflect actual conditions at the farm. So, it is imperative pullets are being weighed regularly so that their feeding regimen can be tailored to their actual weight and condition. To this end, it is important to weigh a sufficient number of pullets that can be a representative sample of the whole flock.
3. Heavier pullets maintain peak production for longer
Despite official guidelines, experience at commercial levels has often indicated that slightly heavier pullets will keep peak production for longer. This extra weight can be as little as 5 percent over recommendations. Its purpose is to balance out any nutrient deficiencies during peak production, as by feeding the flock as an “average” we cannot avoid underfeeding the super-efficient layers without wasting nutrients on the underperformers. Thus, a few extra grams of body weight is usually considered beneficial, especially in the shell egg market. The extra feed required is worth considerably less than the extra eggs produced.
4. Keep underweight flocks on better diets for longer
It is quite understandable to expect actual, local conditions to often retard growth during the rearing period. Such is the case during hot weather, after the outbreak of a disease or a mistake in feed delivery, etc. Thus, during the routine weekly weighing of the representative sample of pullets, they might be found to be below expected weight for their age. In this case, pullets might be offered more feed, if they are not already eating at maximal genetic capacity, or kept on current (better) diets for longer until they catch up. This process should be a gradual one so as to avoid a sudden increase in body weight that will require an equally abrupt deceleration when the pullets are in line with expectations. Again, it is emphasized to follow the actual weight curve and not ideal prescribed time-based guidelines.
5. Do not halt growth in overweight flocks
It is equally possible for pullet flocks to be found heavier than expected, usually when a grower wants to make sure pullets make a good start. If this happens, then it is strongly advised to avoid decelerating the pullets abruptly. Instead, they should be kept on the same feed intake levels until they attain the desirable body weight for age. Alternatively, they can be switched earlier to the next phase diet, or a combination of both might be necessary in extremely heavy flocks. It is important to allow birds to continue to grow and not halt growth (feeding them close to maintenance) until they are fit and trim.
6. Pre-layer diet — to feed or not to feed?
Most experts recommend a pre-layer diet during the last two weeks before the onset of egg production. This is usually from the 16th to 18th week of age for most strains. Such diet is virtually identical to the last (developer) diet being offered, with the exception of calcium. Where a developer diet has no more than 1 percent calcium, a pre-layer diet often contains more than double this amount. This is done to ensure birds are fully prepared for the onset of egg laying process that places a strong demand on the daily calcium cycle. However, some nutritionists raise concerns about possible kidney failure later in life due to such high overloading with calcium. As it happens, the truth is somewhere in the middle, and each flock should be evaluated individually whether a pre-layer diet is required and if yes, for how long it should be fed. Some experts believe a pre-layer diet is not required if the layer diet is introduced early enough, but this is more of a practical approach that aims to eliminate handling of an extra diet.
Learn more about daily calcium cycle in layer hens