This newsletter comes to you as the maize harvest begins to come in. The good news is that some normality has returned to the market. The bad news is that maize this year will sell for almost double what it sold for last year.

Unless the prices of our products increase dramatically we will continue to have to operate under conditions of a poor feed price ratio. This means that we can only buy a small amount of feed with the proceeds of the sale of a kg of product. Walter and I have written two articles (in Porcus and in the Poultry Bulletin) on the best way in which to cope with this problem on farm. I do not intend to repeat the information contained in these articles but it is perhaps well to point out the key issues here as well:

When feed price ratios are poor, the only way in which money can be made is to ensure as high a

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We held a most successful poultry course in May, which by my records is the tenth time that we have run it. This means that there must be about 200 people in industry who have attended over the years.

As you may remember Shaun Storer has always handled our Dairy Course for us. As his involved in the church has increased so he has less to do with nutrition and he has asked that we find an alternative lecturer for the course. I have approached John Evans of Evans Johnson Associates to see if he would be interested in becoming involved with us and am delighted to say that John has agreed. This means that our next Dairy Nutrition Course will be held in Johannesburg from the 17^th to the 19^th of September.

The cost of the course will be R 1800.00 per person. Should you wish to attend, please contact Bianca at the SPESFEED office.

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We are involved on the periphery of an exciting new product called Stalosan F, which originates from Stormøllen A/S in Denmark.

A Danish vet invented Stalosan F 35 years ago, in an attempt to overcome the problem of freezing experienced with normal disinfectants. It is a fine pink powder that is completely safe for both animals and humans, even when consumed in large quantities. It comprises natural mineral salts and is manufactured over a 60-day period, so producing a product with an enormous surface area.

It is effective against bacteria, viruses, fungi and some parasites such as coccidia, fly larvae and certain parasitic worms. It is "green" and has been shown not to have any impact on the environment, yet it can modify the environment by reducing the levels of ammonia and hydrogen sulphide in animal housing.

This patented product’s mode of action is through adsorption and desiccation of the organisms always present in animal housing. It is very fast acting and will kill most pathogens within 5 minutes.

Stalosan F is easy and safe to apply by hand but recent work in the US has shown that it can be spread effectively using a powder blower. The application rate is 50g per m² and for long lasting protection it should be applied weekly.

Obviously its application in animal production systems is limited only by our imagination. In the 35 odd countries where it is now used it has found a many number of uses. For example it has been widely used in farrowing crates and weaner pools in pigs, in horse stables, in calf pens and even in pigeon lofts. There is no reason why it could not be used in hatcheries, in broiler housing or even to replace foot baths on pig and poultry farms.

The cost of 25kg of Stalosan F is much the same as 25 liters of liquid disinfectant and it will be available through NuTec South Africa.

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The 5th edition shifts emphasis to the commercial business of managing poultry. It contains over 75% new material with contributions from 14 new authors. The volume contains over 300 tables and 250 photos and figures in 11 sections containing 62 chapters of text.

We have "translated" the broiler performance data published by the Department of Avian Medicine, University of Georgia (The Informed Poultry Professional, Feb 2002) for your interest. These figures were worked on an exchange rate of R 10.00 to the US$.

As mentioned earlier, measuring the Unit Profitability (UP) of an operation is all important. In order to do this properly, feed trials often need to be conducted on specific farms.

In order for a feed trial to be effective and the results meaningful there are two key requirements that need to be met. Firstly, we must minimise differences in animal performance due to factors other than the feed, and secondly, we must interpret the results in such a way that they are valid.

In order to conduct a trial properly there are a number of important steps that must be followed:

Weighing: All animals and feed must be weighed on an accurate scale. DO NOT rely on guesswork.

Adequate Replication: Having only one pen of animals per feed type causes misleading results.

Select Proper Pens: Pens and houses must be identical in all aspects (size, equipment, floor etc.). Pen/house location in the building or on the farm should not be allowed to influence the outcome of the trial, for example a draught at only one end of the house. Blocking is a technique used to ensure a fair comparison. Adjacent pens, each with a separate feeder, constitute a block.

Eight pens are available. Create blocks with two pens in each. Randomly assign a feed type to the first block in each pen. The other pen gets the feed type not selected.

Select Suitable Test Animals: In order to eliminate possible differences it is always easier if there is only one sex being dealt with. Select similar animals (same weight) from the same set of offspring (litter or parent flock) and randomly assign the correct number of animals to the test and control diets.

If an animal dies before the trial is completed, data collected from the dead animal’s pen must be adjusted. Subtract the dead animal’s on-test weight from the pen’s total. Adjust pen feed intake by determining average daily feed intake per animal for the period in which the animal was alive. Multiply this by 0.75 to estimate daily feed intake by the dead animal. Calculate total feed consumed by the dead animal for the period in which it was alive. Subtract this from the total feed consumed in the pen for the same period. Determine the quantity of feed remaining in the feeder the day the animal died. All animals should have been treated in a similar manner in the period prior to the trial (same vaccinations and feed).

Tabulate Results and Draw Conclusions: Once the trial has been run for some predetermined period calculate and tabulate average daily gain, daily feed intake, feed conversion efficiency (feed/gain) and feed cost per unit gain for each pen or house in the trial, for each feed type (control and test). Determine average performance for the control and test groups. These parameters do not take into consideration that the results may have been due to chance.

Statistical Analysis: To make a valid conclusion about any trial some form of statistical intervention is required. We discussed just how important using the correct statistical methods (Summer 2001) are in nutrition so we will not repeat this detail here. However, should you conduct on-farm trials and require complete statistical analysis of the results we would be only too happy to help.

The value of any ingredient is determined by it’s own nutrient composition, the diet in which it is to be fed (broiler or layer) and on the price, availability and nutrient composition of the other ingredients available. Lastly, use of the ingredient needs to be practical. Table 1 shows the relative value of some alternative grains in poultry diets, assuming of course that all of the grain is freely available.

When examining these options one is not filled with all that much hope. Wheat is mostly too expensive, while sorghum is only available in limited quantities. In addition some varieties of sorghum contain dangerous levels of tannin.

There is a possible alternative to the "traditional" products shown in Table 1. The World Bank (1996) published a pamphlet entitled "A New Generation of Pearl Millet on the Horizon". The University of Georgia (2001) has this to say, "Pearl millet is poised to rival the States mainstay crops".

In the United States, mycotoxins were found not to be a major problem. Pearl millet appears to be resistant to Aspergillus flavus infestation. It is susceptible to infection by Fusarium fungi. When harvest was delayed 50 days post anthesis Fusarium species were found in 71.5% of the grain samples. However, levels of Fusarium toxins remained very low.

In the past few decades this traditional crop has been the focus of an intensive effort by the plant breeding community to improve not only its disease resistance (it is susceptible to Downey Mildew) but also its yield of grain. It is now possible to buy Hybrid varieties of Pearl Millet (the first commercially available strain of pearl millet bred for grain is known as HGM 100™) that mature in 90 –95 days, as opposed to the 110 to 120 days of the unimproved varieties. Yields of 3 to 5 tons/Ha are normal as opposed to the 1 ton/Ha reaped from unimproved varieties. There are even some reports of yields as high as 8 tons/Ha. These new varieties and that are mostly resistant to Downey Mildew and other diseases. In addition, millets do not contain the harmful tannins that some varieties of sorghum do.

Lawrence (1995), working on pigs at Perdue University, showed that the energy digestibility was lower for pearl millet (75%) than for maize (86%); and in conjunction with a lower dry matter digestibility, resulted in lower digestible and metabolisable energy values for pearl millet (12.22 and 11.88 MJ/kg, respectively) than for maize (13.27 and 12.88 MJ/kg, respectively). These energy values are similar to other values that have been published and were used in the compilation of table 1. An experiment was then conducted where pearl millet was substituted for maize on a weight basis. This resulted in non-significant (P>0.05) numerical increases in the rate of BW gain and feed intake (Table 2). FCR was also unaffected (P>0.05) by substitution of pearl millet for maize. Body weights were similar across dietary treatments at the end of the 28-d experiment.

The fact that all of the results presented in table 2 were not significant is of interest in itself. Not only would this indicate that pearl millet can safely (and successfully) be used to replace maize in pig diets, but is would also indicate that the true energy value (Net Energy) of maize and pearl millet were comparable and the differences found to exist in the Digestible Energy values were perhaps not valid.

Collins et al. (1995) found that millet and maize gave equivalent egg production and feed efficiency. However, the fatty acid profile of the eggs produced by millet-fed hens differed significantly from those from maize-fed hens. Feeding millet produced eggs that were higher in mono-unsaturated and omega-3 polyunsaturated fatty acids (PUFA), and lower in omega-6 fatty acids than when feeding any other common cereal (Table 3). Since mono-unsaturated and especially omega-3 PUFA may offer health benefits to consumers, pearl millet may offer one route to a more healthy "designer" egg.

Davis et al. (2002) of the University of Georgia replaced 33.3% of the maize in a broiler diet with pearl millet. Mixed-sex broilers were fed the experimental diets. At 6 weeks of age the broilers fed the pearl millet containing diets had an average body weight of 2.172 kg with an FCR of 1.689. Those birds fed the control diets had an average body mass of 2.069 kg with an FCR of 1.652. Interestingly, the carcass body weight of females of the millet fed group was significantly higher than the control, while for the males the differences were not significant. This result would certainly confirm that the value of pearl millet has a higher feeding value in poultry diets than maize does.

Clearly certain varieties of pearl millet produce crop yields that are worth out attention. Australian workers have shown that millet will have higher yields than sorghum and maize in low rainfall (200-500mm), sandy, well-drained environments. The gross margins for dryland millet, sorghum and maize are $240, 56 and $4 respectively and under irrigation $426, $182 and $379 (all figures in Australian $).

Wild birds eating the crop may be a problem.

Processing and handling pearl millet feeds requires some practice, but no special equipment. Harvesting equipment should be carefully adjusted to thresh the small seeds completely, because poorly threshed millet has lower feeding value. Grinding or rolling is probably necessary for pigs, because experiments indicate that small unground seeds may not be fully digested. I would suspect that it does not need to be milled in poultry diets. Pearl millet pellets well and feeds made with it tend to flow much more easily than traditional maize-based feeds.

Agronomists and extension personnel in Georgia in the US are going to great lengths to convince farmers that pearl millet is a viable crop for them to produce. Not only are production costs lower than those for maize, but yields are fair and the value of the grain is higher. South African agronomists that I have spoken to seem not to be aware of this crop. I am however convinced that this is a crop that South African farmers need to investigate and take seriously. If the pig and poultry industries were to create a market for millet, this is a trend that will occur by itself.

At NuTec’s 4^th International Poultry Symposium, Dr Mario Penz of Nutron, Nutec’s sister company in Brazil, gave an excellent paper on broiler nutrition. This excerpt is the first of a few that I will use in the newsletter as time goes by.

The optimal particle size of broiler diets has been subjected to much debate among nutritionists. However, in order to do this properly it is essential that particle size be described accurately.

Particle size is established by the mean geometric diameter (MGD). Complete information on particle size must include a measure of dispersion, which is known as the geometric standard deviation (GSD). According to Nir et al. (1994), the lower the GSD, the better the performance. Those authors showed that when the GSD was near 2, independent of the MGD, broiler performance was impaired (P<0.01).

Nir worked with broiler diets based on maize, wheat or sorghum using a roller mill, and divided the particles into small (DGM de 0,57 a 0,67 mm), medium (DGM de 1,13 a 1,23 mm) and coarse (DGM de 2,01 a 2,10 mm). Broilers were fed from 1 to 21 days of age. No difference in performance was found during the period of 1 to 21 days of age, but there were significant differences (P<0.01) during the period of 7 to 21 days of age. Broilers fed fine particles, independent of the grain used, had lower feed

intake, lower weight gain and worse feed conversion (Table 2). They observed that gizzard weight and content of 7-day-old broilers fed finely ground grains were lower (P<0.01) and the pH higher (P<0.01) than broilers fed larger particles. The same differences were observed at 21 days of age.

Magro & Penz (1998), working with diets containing increasing particle sizes, found that the best production results were obtained with the lowest MGD feeds, and the established value was similar to that recommended by Nir (Table 3).

In general discussion, the question as to which was more important, pellet quality or particle size? Dr Penz was of the opinion that, even if pellet quality was poor, the larger particle size made up for this shortcoming to a certain extent.