Dear Akbar Yaghobfar thanks for your question. The level of 0.52% of digestible lysine for breeder 3 is for almost all broiler breeder lines. Except for broiler breeders that produce high breast meat yield such as Cobb 700 and Ross 708, for these hens the digestible lysine and all amino acids can be increased and without egg overweight.
Hope this helps,
Best regards.
Serdar Özlü Thanks for your question.
With a poor rooster management, reduced hen feather quality, and egg oversize, one flock might drop the fertility in around 20% or more. Indeed, spiking and intra-spiking might increase the fertility between 3% and 5%, after 35 weeks of age, however, this will not recovery the heavy reduction of fertility (-20%) in your flock.
Thanks a lot for the valuable suggestions. What are the other ways to improve the fertility and hatchability?
Dear Sandro Cerrate,
My name is Carlos Borges I am a Nutritionist and I work with consultancy ( C Borges Consultoria)here in Brazil.
My PhD thesis was on “Nutritional Requirements of Protein and Energy for Breeding Roosters in the Production Phase”
During the work that was quite long, because we worked with the roosters still in the breeding and before mating and we took the experiment until 62 weeks of age we reached the following conclusions:
- Currently, it is justified to use a specific diet for breeding males that meet the nutritional requirements of energy, protein and amino acids in the production phase.
- The lack or excess of protein for breeding roosters during the production period mainly affects the quality of the semen (motility and vigor) and decreases the fertility of the flock
- Excessive energy consumption increases the body weight of breeding roosters making them obese and, consequently, leading to both physical and mechanical infertility.
We evaluated the quantitative (volume and sperm concentration) and qualitative (motility and vigor) characteristics of semen from breeding rooster from 27 to 62 weeks of age, concluded that the consumption of 17 g of protein/rooster/day was the most adequate to supply the needs of breeding males in the production phase.
And the consumption of 360 kcal of metabolizable energy/rooster/day was enough to meet the energy requirements for broiler breeders in the same period.
It is important to note that the experiment was carried out in boxes with 1 rooster for 10 hens with natural breeding.
Dear, Sandro Cerrate,
I fully agree with your statement that the ideal would be to work with different rations respecting the age and body weight of the rooster, this also serves for the female because the maintenance requirement will vary according to body weight and physical activities and in the case of female still producing eggs. However, in practice, this is almost impossible due to problems in the feed mill and logistics. I am saying this because I have worked with broiler breeders for over 30 years and worked as a Nutritionist for 11 years at one of the largest broiler and swine production companies in Brazil.
To answer the question from a colleague who wants to know about feed intake/rooster/day and nutritional levels in the period of production indicated:
Approximately 133 g of feed/rooster/day with 12.5% CP and 2,700 kcal of metabolizable energy in the diet.
I want to remember that my thesis was done with males and females in boxes (floor), therefore with natural mounts and with a ratio of 1 male to 10 females.
Dear Dr. Cerrate. Very interesting article, thank you. I think the section on egg size and amino acid balance needs discussion. I agree that the ONLY way to achieve better results is to ensure the supply of balanced Standardised Digestible amino acids is correct. I disagree that lysine is the main driver of egg size; this is actually methionine + cysteine, the sulphur-containing amino acids (SAA). As most poultry diets are based on maize and soya, SAA are usually first limiting. Furthermore, the concept that there is a link between breast muscle growth and egg size is not correct. Finally, excess levels of lysine will NOT result in higher breast muscle growth. First, in a mature animal like a broiler breeder, muscle growth is primarily determined by genetics and activity, not nutrient supply; and second, as soon as any other amino acid becomes limiting, excess lysine will simply be de-aminated and excreted. The correct approach would be physical feed restriction or rebalancing all nutrients to a lower level.
Martin Smith Thanks for your comments. This is a great input and let me explain more. In practical diets for broiler breeders the methionine (M) and cysteine (C) are limited and most diets cover the minimum requirements. And flocks fed with levels of M+C that match the requirements shows egg oversize. Why? In practical diets of broiler breeders the digestible lysine is above the requirements, meaning the synthetic lysine is almost not used in breeders diets, except in the pre-starter pullet diets, said this, the excess of lysine coming from the ingredients produces egg oversize and big muscle yield. Sure, in practical diets other amino acids along with lysine such as isoleucine and leucine for example are also at high levels when lysine is above the breeder requirements using corn and soybean meal. On the other hand, I did a review with 13 review-papers that show the amino acids requirements using synthetic amino acids in broiler breeders. In this analysis, the most important amino acids that reduced the egg size was the M+C (1.1 g), lysine (1.2 g), and valine (-1.6g). However, they also reduced the egg production, first was the M+C (-6.6%), then Lysine (-4.0) and then Valine (-2.0). This is reducing at 25% less of the AA requirements. I did lab and field studies, and they indicate that the breast meat and egg size correlate strongly. See the studies of Dr. Coon;s lab that I participated on them, specifically Ekmay's paper. As broiler breeder hens age, the lysine from the eggs coming from lysine of the muscle increases; we did this study using labeled amino acids. Further, working in the field with broiler breeders, I used a device to measure the angle of breast meat in vivo. In flocks with more angle meaning more breast meat, the hens layed bigger egg size. Further, when we touched the breast meat of hens from egg oversize, the flesh was harder, like a rock. In contrast, in hens from smaller eggs, the breast meat was softer by palpation. After this observation, I measured by a durometer, the harness of the breast meat in live hens, and indeed they reported higher numbers, meaning hens with egg overweight also had harder breast meat. With clients I see the same output: when the lysine is reduced to match the breeder requirements, the egg size was reduced and hatchability improved. I agree with you also that egg size is also determined by the genetic. There are lines that tend to produce a larger egg size than other. Further, another important point is the level of egg production, flocks with poor egg production tend to produce larger egg size. Hope this helps in the discussion. And best regards.
Dear Sandro Cerrate:
Thanks so much the article is very useful in practice usually I use canola meal or sunflower meal with soybean meal in rearing after 4 week of age and in production period in broiler breeder farm and calculate the amino acids as digestible according to genetic company recommendation and obtain tow good result :
1- The good feathering and persistency of feather in production period.
2- The good egg size that always is equal to genetic company or 1 gram below it.
Because of the effect of sodium deficiency in feather peaking calculate it to about 0.18% by using sodium bicarbonate in diet.
As you know formulation the feed for Rooster only with corn+soybean meal and wheat bran is wrong because of high soluble fiber in it, hence using canola or sunflower meal will facility to
formulate the Rooster diet and good fertility in them.
I agree white you the high level of lysine is detrimental for production and hatchability regardless of this reality that it is a ketogenic amino acid, high level of it will increase the size of breast of hens and mating with these hens will be difficult by Rooster because cloaks cant contact together and void of semen not occur.
Your thesis and practical work will help the formulation of our feeds for optimum growth and output, kudos!
Hi Dr. Akbar Yaghbi:
Thank you for your comment about using insoluble fiber in rooster feed. I like to inform you it will be as the amount of sunflower or canola meal is allowed not more and will be used in combination with others like soybean meal and wheat bran. And because of this the amount of the insoluble will remind in acceptable percent that not interfere whit absorption of other nutrients like micro mineral as you mentioned.
Despite this refer you to ROSS recommend in using some material like sunflower and canola in AVIAGEN site in feeding broiler breeder.
And I like to inform you as Aviagen recommendation it is a long time I use them and obtain best result in rearing and production period, feather covering, fertility, hatchability and best chick quality not only in broiler breeder but also in layer breeder.
And you know that insoluble fiber in poultry nutrition is regarded as a nutrient and must be in feed formulation and has good effect in retention time and digestion and absorption of nutrients.