Be taught extra about managing body weight uniformity
25 July 2024
3 minute learn
Editor’s word: This text is an excerpt from the Cobb Breeder Administration Information and extra articles will observe. The Information was designed to spotlight crucial elements which are almost certainly to affect flock efficiency. The administration suggestions mentioned had been developed particularly for Cobb merchandise. The suggestions are supposed as a reference and complement to your individual flock administration abilities so as to apply your information and judgement to acquire constantly good outcomes with the Cobb household of merchandise. To learn or obtain the whole Information or to view Cobb’s different administration guides, click on right here.
Beneath is an instance of a body weight recording chart.
Common Body weight
Utilizing the chart above, the typical weight was calculated:
Complete weight of 100 birds = 59.5kg (131 lb)
Common weight per fowl = 595 g (1.31 lb)
One other strategy to rapidly calculate the typical flock body weight is to seek out the fowl within the center of the pattern. (In above instance, the center fowl shall be #50). Make a cumulative calculation of the fowl numbers (final column of desk) to seek out fowl #50 which is between 44 and 67 or between 580 and 600 g. Then common these weights (590 g). Though this deviates 5 g from the usual calculation, it’s a fast and environment friendly estimate.
Normal Deviation (SD)
The usual deviation is a measure of how broadly values are dispersed across the common worth (the imply). In a traditional flock, roughly 95 % of the person birds will fall in a band +/- two commonplace deviations both aspect of the typical body weight.
Coefficient of Variation (CV)
The coefficient of variation (CV) is usually used to explain variability inside a inhabitants. A low CV signifies a uniform flock. A excessive CV signifies an uneven flock. Variation could be expressed both when it comes to common fowl weight, commonplace deviation of body weight, or coefficient of variation in body weight
Utilizing the information above, CV was calculated:
(Normal deviation (g) ÷ common body weight) X 100 = CV
(35.7 g ÷ 595 g) X 100 = 6
Uniformity
Uniformity is a measure of the variability of fowl weight in a flock and is measured by weight +/- 10 % of the typical body weight and/or by coefficient of variation.
To calculate flock uniformity
- Depend the variety of birds which are within the 10 % vary on both aspect of the common body weight of the 100-bird pattern.
- Subtract the entire variety of birds which are outdoors the ten % vary from the 100 birds sampled. This quantity is expressed as flock uniformity proportion.
Utilizing the information from the earlier web page for example:
6 birds (+ 10 %) + 4 birds (- 10 %) = 10 birds whole outdoors the ten % vary
100 birds sampled – 10 birds whole outdoors the ten % vary = 90 % uniformity
Sustaining good uniformity
A uniform dad or mum breeder flock shall be simpler to handle and can produce extra chicks per hen housed than an uneven flock. Good uniformity outcomes from cautious consideration to element.
Components resulting in body weight uniformity issues
- Mixing day outdated chicks sourced from mother and father with excessive age variations
- Incorrect nipples for fowl age
- Inadequate water provide or availability
- Beak conditioning, if not carried out at a excessive commonplace
- Incorrect feeding house, feed quantities or poor feed distribution (feed not making a whole loop)
- Too excessive or too low vitality feeds and never balanced with protein and amino acid profile
- Incorrect or variable pellet measurement
- Incorrect feeder peak
- Irregular feeding instances (at all times feed on the similar time)
- Quick feed cleanup time (lower than half-hour)
- Poor air flow and excessive temperatures
- Poor lighting (distribution or uniformity)
- Over stocking
- Uneven fowl distribution over the size of the home
- Incorrect fowl numbers or pen drift
- Illness or parasitic infections
