The rising demand for feed is the major concern of the changing globe that affects all sectors of the food industry, including agriculture, aquaculture, poultry, and livestock. As a result, there is rapid competition for feed supplies. Because of the expansion of the poultry and livestock industries to meet the need of the constantly growing population, there is currently a global shortage of many essential feedstuffs. Additionally, the aquaculture industry is having a harder time finding more affordable sources for necessary feed ingredients. Due to climate change and environmental deterioration, conventional feed is becoming more and more scarce. This calls for the conversion of non-traditional feed materials into value-added feed ingredients. Therefore, collaboration among nutritionists, feed technologists, and data scientists is vital to the future optimization of low-cost alternative ingredients in a high-quality feed product [1].
In Pakistan, domestic feed supplies fall short of the demand for livestock and poultry. For dry biomass, crude protein, and metabolizable energy, the disparity between supply and demand is 19.4%, 37.2%, and 38.0% respectively. Crop residues make up most of the feed supply, which is then followed by fodder and grazing. Of the overall supply of feed, 8.2% is made up of grains and byproducts. Large amounts of soybean meal and other feeds are imported to close the gap between supply and demand. The feed gap is expanding quickly due to the rapid growth of the poultry, dairy, and feedlot industries. Animal nutritionists now place a greater emphasis on the effective and sustainable use of local non-conventional feed supplies due to the trend of rising feed demand [2].
Pakistan's domestic feed supplies fall short of the demand for livestock and poultry. For dry biomass, crude protein, and metabolizable energy, the disparity between supply and demand is 19.4%, 37.2 percent, and 38.0 percent, respectively. Crop residues make up most of the feed supply, which is then followed by fodder and grazing. 8.2% of the overall supply of feed is made up of grains and byproducts. Large amounts of soybean meal and other feeds are imported into the nation to close the gap between supply and demand. The feed gap is aggressively expanding because of the rapid growth of the poultry, dairy, and feedlot industries. Animal nutritionists now place a greater emphasis on the effective and sustainable use of local non-conventional feed supplies due to the trend of rising feed demand [3].
Animal nutritionists are turning to alternative sources of protein in diet formulation due to the scarcity and rising expense of high-quality protein feed ingredients. Unconventional sources of proteins, carbs, and minerals can be utilized to make products of high nutritional value for animals. In the upcoming decades, an increase in fish and meat production will be seen. Non-conventional feeds will serve as an alternative to conventional fish and livestock feed. In this connection, the duckweed (Lemana minor L.) comes to be one of the efficient candidates to meet the demand. This plant produces enough biomass that can be harvested from wastewater bodies and can easily be made accessible to the feed market. The investigation on comparative life cycle assessment shows that feed based on Lemana minor is ecologically competitive and more sustainable than standard feed [4].
The capacity of Lemna minor in wastewater bodies under diverse ecological conditions makes it one of the ideal candidates to be used as non-conventional feed. The plant can grow vegetatively with the help of fronds and can double the biomass within a couple of days. In certain European regions, the potential of Leman minor to grow and convert agricultural wastewater into a high protein feed to comply with the rising demand for animal feed protein is well established. The plant has the potential ability to absorb nutrients from the water and convert them into essential feed components. In nutrient-rich agricultural wastewater, the aquatic macrophyte can grow and be harvested with a 35% dry biomass content of protein [5].
The growth and nutritional parameters of Lemna minor vary greatly with the alteration of environmental conditions like pH, salinity, and macro and micronutrients [6]. Pakistan is rich in wastewater bodies with diverse biochemical conditions in different parts of the country. Domestic and industrial wastewater in Pakistan is either directly released into the sewage system, a neighboring field, a natural drain or water body, or an internal septic tank. Except for Islamabad and Karachi, none of the cities have any biological treatment methods, and even these cities only handle a small part of the wastewater [7]. The current study focuses on the following cherished objectives.
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To estimate the impact of different pH on growth and biomass production of Lemna minor.
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To assess alterations in nutritional parameters such as lipid, protein, carbohydrate, and minerals with altering pH.
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To determine the optimum pH range that will allow Lemna minor to be grown and used as feed under the agroclimatic regime of Pakistan.