Vitamin Levels in Breeder Diets

Hubbard breeder hens are capable of peak egg production around 86% under commercial conditions, with sustained peaks over 80% for 12 weeks. This high egg output is only possible with superior management and nutrition, part of which is a well-fortified high energy diet. These high persistent peaks also mean that we have to supply adequate vitamins in the feed, not only for the hens very active stage of reproduction, but also to ensure optimum hatchability and chick quality. Unfortunately, what we consider to be optimum vitamin needs of the breeder are often questioned as being too high and too expensive, when in reality it is low-vitamin levels in the feed that are ultimately the "most-expensive" scenario for the bottom-line of the breeder or integrated broiler operation.

Diets for adult breeder hens probably contain the highest level of supplemental vitamins of any feed manufactured at a commercial feed mill. These vitamins are required for the normal function of most physiological processes in the body, and for the breeder hen we have the added need for adequate carry-over into the eggs. Unfortunately a deficiency of any one vitamin can cause a dramatic decline in egg production and hatchability, and yet the levels recommended by Hubbard and other breeders are often questioned as being too high, and therefore too costly. We usually meet the breeders' requirements for vitamins by adding all as synthetic sources. The regular feed ingredients, such as corn, soybean meal and meat meal, all contain "natural" sources of vitamins and in some situations could theoretically contain enough to meet the breeders' needs.

However the concentration of vitamins contained in corn will, for example, be affected by seed variety, growing conditions, harvesting conditions and storage conditions. Likewise the vitamins in meat meal will vary greatly depending upon the animal components used and the time and temperature of cooking and drying during processing. Obviously these ingredients come with no guarantees of vitamin levels, and bioavailable concentrations are expected to vary 200-300%. In addition to this inherent variability is the effect that factors, such as natural plant toxins and mycotoxins, can have on vitamin availability. For example, recent research data showed that the effects of a certain mycotoxin could be largely overcome by adding more thiamine, a B-vitamin, to the diet.

On this basis it is perhaps not too surprising that we do not rely on regular feed ingredients to supply vitamins, and consequently our vitamin premix is designed to supply all necessary vitamins for the bird. However this still does not answer the question of "why such high levels of vitamins in breeder feeds." The starting point used in developing vitamin requirements, is the NRC values which are updated each 6-8 years. These NRC values are absolute requirement values for individual vitamins, and most often reflect the level of vitamin needed to prevent deficiency symptoms.

In feeding breeders we want not only to prevent signs of vitamin deficiency, but also to ensure good egg production, hatchability and early chick vitality. This superior performance will only be achieved by feeding much higher levels of vitamins as part of a balanced nutritional program.

Another reason for higher vitamin fortifications relative to NRC (1994) is the loss in potency of vitamins that occur between feed manufacture and consumption by the bird. Different vitamins are susceptible to various stresses to varying degrees, but as a generalization it can be stated that the major causes of loss of vitamin potency are storage time, storage temperature, and storage humidity of the premix before mixing, and of the feed after mixing. Another major loss of vitamins occurs if they are premixed with minerals and stored for any length of time prior to incorportion in feed. Also conditions within the premix and feed can cause loss of potency. For example, some vitamins are acidic whereas others break-down under acidic conditions. Finally to really cause problems to vitamin stability, we sometimes pellet feed, and here the temperature and humidity can cause vitamin breakdown.

The manufactures of vitamins are able to tell us factors which affect potency of their vitamins, and so with this knowledge, coupled with anticipated field conditions, we can project necessary safety factors to ensure optimum breeder performance.

The next question is how much does it cost to add these higher levels of vitamins, and are they worth it? BASF, a major producer of pure vitamins, recently conducted a survey of breeder operations in the USA and, as anticipated, found a range of vitamin levels being used. This industry data covered 62 broiler companies and represents about 90% of the industry. Table 1 shows the highest and lowest vitamin levels being used, and these are compared to NRC (1994). There is about a 100% difference between the top 25% and bottom 25% of reported levels for vitamin fortification. Table 1 also shows the cost of obtaining these individual vitamin levels, and the total cost per tonne of mixed feed.

Table 1. Breeder vitamin levels and costs

Vitamin Levels in Breeder Diets - Image 1

* = BASF Technical Bulletin #KC9305

Obviously the bottom line is how well do breeders perform based on high vs low-industry values. We do not have this data, but we can see that the higher vitamin levels cost us about 10¢ more per breeder, which in most markets is equivalent to 0.5 chicks per breeder. Considering that a number of the low-industry vitamin levels (Table 2) are even less than NRC (1994) we can be sure that this will affect performance, and from our experience, this will be much more than 0.5 chicks per breeder. Marginal vitamin levels can easily result in loss of 2-5 chicks per breeder, which is 4-10x the cost of the extra vitamins in the feed.

Our recommendation is, therefore, to feed adequate levels in the feed, because this ensures optimum delivery of vitamin to the breeder and the developing embryo. With these extra levels of vitamins in the feed, there should be no need to use supplemental vitamins in the water, except in situations of environmental or disease stress when feed intake is not optimal, or there is evidence of enteritis.

If vitamin levels are to be adjusted according to local conditions, then which ones are most likely to influence feed cost? Table 2 is a repeat of the industry high-level breeder vitamin recommendations, but in this situation they are listed according to contribution to cost of the premix. This data shows vitamin E, biotin and vitamin A to be the most expensive, and together make up over 50% of the cost of the vitamin premix. These three vitamins should, therefore, receive most attention when additions to, or deletions from premixes, are contemplated based upon knowledge of specific needs within a feeding program.

Table 2. Vitamin recommendations ranked by $ cost/tonne feed

Vitamin	$/tonne feed	% contribution to premix cost
Vitamin E	1.08	23.7
Biotin	0.77	16.9
Vitamin A	0.68	14.9
Riboflavin	0.53	11.5
Pantothenic Acid	0.38	8.3
Pyridoxine	0.31	6.8
Niacin	0.27	5.9
Vitamin K3	0.13	2.9
Folic Acid	0.13	2.9
Thiamine	0.11	2.4
Vitamin B12	0.09	2.0
Vitamin D3	0.08	1.8
Total	$4.56	100.0

Vitamins are expensive, and together the premix represents about 2-3% of the cost of breeder feed. However the effects of deficient or marginal levels in breeder feed can be far greater than the 10¢ per breeder to be potentially saved by feeding at the low vs high end of current industry standards.