APPROACHES IN FEEDING MANAGEMENT TO REDUCE WASTE ODORS IN MONOGASTRIC AND POULTRY
ROGER ROQUE E. BUSTAMANTE
PROJECT IN ANSC 242
FEED FORMULATION AND QUALITY CONTROL
2016
Introduction
With the growing concern of the undesirable effect of livestock production on the environment, it is evitable that the animal industry should take action in order to ensure long term sustainable growth. Formerly, adjustments of the dietary requirements in maximizing production performance are the focus of the animal nutritionists. They did not consider the nutrients (amino acid and protein) that are overly supplied and wasted that have caused environmental pollution. Animal production encompasses all aspects that must be given attention. An animal raiser should consider every aspect as equally important. Its aims are to produce good quality products in general. There is so much improvement in every aspect in the field of animal production like in animal breeding and especially in feed formulation for the animals in order to increase efficiency and productivity in animal agriculture (Hribar and Schultz, 2010). On the contrary, the current animal production systems are inefficient converters of feed to the desired animal products. This inefficiency is true for nitrogen, phosphorus, and potassium. The large fraction of these elements were not utilized properly and not converted into desired animal products, but was only wasted as animal manure as a combination of feces and urine (Tamminga, S. & Verstegen, M. 1996).
Now, animal nutritionists’ and feed companies are more focused on improving the nutrition that can be absorbed by the animals from the feeds that were given to them. Since the focus is only on that aspect, they were not able to recognize the effect on the feeds given to the excretion of the animals that can affect the environment in general. According to Powers (2010), livestock production has caused serious damage to the environment and for the reason that the livestock production is increasing to meet the demands of the consumers, the aerial emission also increases. The losses mentioned by Powers (2010) are one of the contributing factors in the global climate change such as the NH3, CO2, and CH4. Meanwhile, Moore, et. al. (1995) have mentioned that the rapid growth of the poultry industry also increases the concern in disposing the waste to the point that this will not be a source of pollution. This situation is not only in the poultry industry but this is true for all industries in animal production. In order to combat these challenges, several approaches in feed formulation may be applied without sacrificing the quality of feeds to be given to the animals with the same dietary requirements should be met and supplied.
According to Sutton, et. al. (1999), wastes from the swine industry is primarily a mixture of urine and feces that contains undigested dietary components, endogenous end products, and indigenous bacteria present from the lower gastrointestinal tract (GIT). With this, dietary manipulation will best resolve this problem and proper management. In poultry production, the waste may include the mixture of excreta (manure- in high amount), litter material, waste feeds, broken eggs, dead birds and even feathers (Kelleher, et. al.(2002) . With all the waste in poultry production, the manure is the most focus because this has a big impact on the environment. On the other hand, Powers (2010) have emphasize in her report that research indicates that dietary strategies can have a profound effect on gaseous emissions, particularly ammonia.
Meanwhile, Mackie, et. al. (1998) have stated that the volume of manures that are being generated may cause a major obstacle in the future development of the animal industry and its impact to the environment will not be properly managed and controlled. With this reason, many types of research have been conducted to find the most effective solution to this issue. Hence, this paper will consolidate research results that will help gain knowledge on how to reduce waste odors in monogastric and poultry.
Objectives
The aim of this paper is to associate research results and scientific reports with several approaches in feeding management to reduce waste odors in monogastric and poultry.
Literature review
One of the very recognizable problems in animal production when talking about the animal wastes is the fecal odor or the emissions from the manure. This not just contribute to the global climate change because of the emissions it also can cause diseases to human. Moreover, Deschepper and DeGroote (1995) have mentioned that pollution with nitrogen originating from animals has become the major problem in European countries. According to Clark, et.al. (2006), the gaseous emissions associated with pig production includes greenhouse gasses, toxic or corrosive gasses, and odorants. These emissions are from the excretion of the animals (urine and feces). The same authors have reported that the manipulation of the diets in swine can reduce the undesirable emissions (hydrogen sulfide) and can possibly increase the desirable emissions (methane for energy generation). Nahm (2007) stated that the dietary levels of nutrients in poultry that is a requirement for growth, maintenance or even for productive functions could balance that would result in minimal fecal waste. Unluckily, there are no perfectly balanced diets for the animals. When there is a minimal fecal waste there is also minimal concerns about environmental pollution (fecal odors). The statement of Nahm (2007) is true for all not just in poultry.
Clark, et.al. (2006), in an article that they have published, it was stated there that diet manipulations that can help reduce emission are usually associated with improving nutrient utilization. Furthermore, dietary manipulations can affect the production of gasses by altering the dietary nutrient content and digestibility.
Dietary Manipulation and Formulation Strategies
The feeding strategy in swine and poultry production has been given with new perception with the advent of the existence of environmental problems that is directly related to pollution of nitrogen coming from animal manure. Before of all the innovations in feeding existed the focus in the dietary adjustments to pigs and poultry requirements was aimed to maximize the production without considering the concern of nutrient oversupply especially protein and amino acids. Furthermore, the environmental problem has forced to base protein and amino acid feeding not only in terms of the retention of N in animal products but in terms of the non-utilized fraction of N that is ingested by the animals. With this, sound management of protein feeding in poultry and pigs necessitates adjustments of protein/amino acid supply to the requirements so as to obtain the lowest level of N output (Schutte & De Jong, 1999).
The increase of the environmental pressures brought by the poultry industry has challenged the current situation of ecological stewardship. With the challenges encountered the nutritionist, poultry and soil scientist and pollution specialists creatively proposing strategies that will help deal with the various practices that were directly associated with the dietary manipulation, litter management in poultry and feed additive utilization to alleviate the potential environmental impact of poultry production. The implementation proves that it is beneficial to both, the poultry industry and the environment (Burgos & Burgos, 2006).
There are nutritional strategies that can help the reduction of the ammonia emissions from animal feces. It includes lowering dietary protein and using of synthetic amino acid supplements to reduce N emission ((Powers, et.al, 2010, Ferket, et.al, 2002). The strategies mentioned were already being tested in swine and in poultry. In a review done by Zhang, et.al. (2002) the dietary manipulations have been shown to potentially reduce odor generation in swine operations.
Reduction of Dietary Protein
Through supplementation of synthetic amino acids, dietary crude protein can be reduced in order to minimize the N secretion from pigs and poultry species (Jongbloed et al., 1997; Sutton et al., 1999; Nahm, 2002). According to Powers (2010), minimization of the N excretion is the most obvious method to control the ammonia emissions in the animal feces. Dietary essential amino acid content should be considered when lowering crude protein. Nahm (2003) mentioned in his article that the uric acid and undigested proteins are the two main N components in poultry manure that have caused ammonia emissions.
Reduction of protein in the diet is achieved through the use of synthetic amino acids. Deschepper and DeGroote (1995) mentioned Keshavarz (1991) postulates stating that the low protein diets increase tolerance of birds in elevated environmental temperature because the heat production associated with the utilizations of protein is greater than with the utilization of carbohydrates and fats. Furthermore, the kidneys are exposed to lower stress in eliminating the end products of nitrogen metabolism and reduced nitrogen excretion lowers the ammonia build-up in the poultry house.
A review of the swine production data was made (Kerr, 1995; Sutton et al., 1999; Han et al., 2001) as mentioned by Rotz (2004) the amino acid supplementation with low-CP diets were found out to reduce the excretion of N by 3 to 62%. The result depends on the size of the pig, reduction of the dietary CP and on the initial CP of the control diet. The average reduction of N excretion per unit of the dietary CP is 8.5%. Nahm (2002) reviewed a poultry data that discussed the dietary changes made to reduce crude protein content using synthetic amino acids have reduced N excretion by about 10 to 27% in the broiler and 18 to 35% in the chick and layer production.
Formulate based on amino acid requirements rather than crude protein (CP).
It is a given that the amino acid is the building blocks of proteins and it includes 20 amino acids. About half of these are essential that must be present in the animal diet and the remaining are nonessential that means the animals are capable of producing adequate amounts based on their requirements. Patterson (2001) has mentioned that the dietary formulation based on the amino acid requirement rather than CP can minimize the N secretion by simply reducing total dietary N intake. It has been reported that the reduction nitrogen excretion is possible, without impairing bird’s performance, provided amino acid levels are adequate.
The use of synthetic amino acids in animal feed has grown rapidly in the past few years and the annual growth rate is 6% (Han and Lee, 2000). Nahm (2002) has stated that the addition of synthetic amino acids and reducing protein content which resulted in N reductions of 10% to 27 %, 18% to 35 % in chicks and layers, and 19% to 62% in pigs and 9% to 43% reduction of odor in pig manure.
Selection of feed ingredients
The quality of feed ingredient (grains, forages, fat, minerals, and vitamins) is a critical part of animal nutrition. Ferket, et.al. (2002) have mentioned that the nutrient digestibility of feedstuff depends on the processing conditions, genetic characteristics and the presence of anti-nutritional factors in each feedstuff. Moreover, they have also emphasized that fine grinding and pelleting feed are effective methods to improve feed use and decrease DM and nutrient excretion. By reducing the particle size, the surface area of the feed ingredient particles is increased which allows greater interaction with digestive enzymes.
To improve the usefulness of the wide variety of feedstuffs, processing methods have been designed in the animal industry. The treatments that have undergone by the feeds have an overall beneficial effect that is intended to alter the physical form, to destroy micro-organisms, detoxify or even removed undesirable substances, to improve palatability and digestibility. Of all the treatments done to the feedstuffs, heat is the most common and effective methods of feed processing that can be used alone or in combination with other technique (Papadopoulos, 1989). Nahm (2002) has mentioned in his work that the use of highly digestible raw materials in feed reduced N and P excretion by 5% in chickens and pigs. Manufacturing techniques such as grinding feed grains with proper particle size, feed uniformity in the rations, and pelleting. If this technique was done properly, this can significantly help reduce the N, P and odor contents and DM weight in the manure in both pig and poultry. He added that with proper grinding it reduced 27% of N in finishing pigs and 22% to 23% reduction of N in the piglet fed with the pelleting technique. There is a 60% reduction of NH3 emission when fed with finely ground Zeolites in pig and 26% reduction of DM weight in finishing pigs with the proper grinding.
Using Feed Additives
Supplementation of feed additives can help reduce excretion of nitrogen and phosphorus through the improvement of feed utilization. The common representative additives to reduce nutrient excretion form animal manure is enzymes. This is used to increase nutrient availability in the feedstuffs used in feed formulation for animals (Han, et. al. 2001).
Commercial application of enzymes as feed additive has a history of less than 20 years. In this time duration, the feed enzyme industry came in many phases of development. The first phase was the use of enzymes to enhance the digestibility of nutrients and having focus primarily on removing the anti-nutritive effects of NSP. Phytase is the prime example of these enzymes that is used not only to increase the utilization of phytate P but also to alleviate environmental burdens by reducing P excretion in the excreta (Choct, 2006). Nahm (2002) has stated in his works that enzyme supplementation has resulted in a 12 to 15% reduction in the dry matter weight of broiler manure. In addition, Phytase supplementation resulted in P reductions of 25% to 35% in chickens and 25% to 60% in pigs.
Phytase is a natural enzyme that is used to improve the nutritional quality of phytic acid rich feed components. Phytase supplementation is a viable strategy to reduce P outputs into the environment (Burgos and Burgos, 2006).
Feeding Management Strategies
Kuczy”ski (2005) have cited Ferket, et.al. (2002) that separate-sex and phase feeding strategies can help optimize the nutritional needs according to the changes that will occur in different stages, sex and even growth potential. Split-sex feeding of swine, in particular, have different nutrient requirements among gilts, barrows, and boars that should be considered.
Separate-Sex Feeding or Split-Sex feeding
Adeola, et.al. (2001) have mentioned the work of Cromwell, et. al. (1993) the separate-sex or split feeding can further improve the feed efficiency. This is well established in gilts consumed less feed in ad libitum basis and require greater dietary nutrient density than barrows. Furthermore, penning and feeding gilts and barrows separately, producers can now precisely formulate feeds for specific sexes that will help avoid excessive excretion of nutrients. In poultry, according to the NRC (1994) report that is cited by Kuczy”ski (2005) cockerels require more dietary protein than hens.
Phase Feeding
Feeding multiple phases allows pigs to be fed more closely to their nutrient requirement and prevents overfeeding of expensive nutrients like protein, energy, and phosphorus. This concept is also applicable to poultry.
Lenis & Jongbloed (1999) have concluded in their review that the introduction of two-three or multi-phase feeding will help the amino acid balance and the digestible P in the diet that is in relation to the requirements of the animals. This idea was supported by the statements of Nahm (2002) in his work that states that phase feeding has reduced N and P excretion by chicken and pigs from about 10 to 33% and 10 to 13% each, as well as the odor in growing and finishing pigs by 49 to 79%.
Warren and Emmert (2003) have evaluated the efficacy of phase feeding in broiler that is being compared to feeding recommendations. In their experiment 1, the control with the recommended requirements for sulfur amino acids, lysine, and threonine was fed from 0 to 21 days while phase feeding was tested using three phase diets. It shows no differences in almost all the parameters, namely; weight gain, feed intake, feed efficiency, digestible amino acid intake, or gain per unit digestible amino acid intake were noted in both treatments.
Conclusion
Therefore, manipulation of the diets in both poultry and swine production is feasible and practical. The knowledge about dietary manipulation and feeding strategies that were being tested by the results of the different researchers can be applied in order to help reduce fecal odors in monogastric and poultry. If not totally solve the problem at least there are ways to combat the environmental challenge caused by the excess nutrients with no use in the body that is excreted by the animals.