INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue IX September 2025
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Evaluation of the Nutritional Content of Abattoir Waste,
Agro By-Products and their Bioavailability to Weaner Pigs.
Victor Odesanmi1, Felix Obazee2, Victor Umar3, Covenant Olawale4, Emmanuel Joseph5
1,5Department of Animal Science, Faulty of Agriculture, Obafemi Awolowo University, Osun State,
Nigeria
*Corresponding Author
DOI: https://doi.org/10.51584/IJRIAS.2025.100900085
Received: 14 Aug 2025; Accepted: 20 Aug 2025; Published: 23 October 2025
ABSTRACT
This study evaluates the nutritional content and bioavailability of abattoir waste and agro-industrial by-
products as alternative feed resources for weaner pigs. The experiment was conducted at the Swine Unit of the
Teaching and Research Farm, Obafemi Awolowo University, Nigeria, using fifteen crossbred pigs (Large
White x Hampshire) with an average initial weight of 10.00 kg. Five experimental diets were formulated,
incorporating different combinations of rumen content, bovine blood meal, palm kernel cake, wheat offal, and
brewers' dried grain, replacing groundnut cake (GNC) as the primary protein source. Results from proximate
analysis revealed significant differences in the nutrient composition of the diets, including variations in dry
matter, crude protein, crude fibre, ether extract, ash, and nitrogen-free extract. Apparent nutrient digestibility
trials demonstrated that the alternative feed ingredients were efficiently utilized by the pigs, with the PKC-
BBM-based diet showing the highest digestibility of dry matter and crude protein. These findings suggest that
abattoir waste and agro-industrial by-products can be effectively used as alternative protein sources in swine
nutrition, offering a sustainable and cost-effective solution to the high feed costs associated with conventional
ingredients. The study highlights the potential for reducing environmental waste while improving the
economic viability of pig production through the use of these non-traditional feed resources.
Keywords - Weaner pigs, Abattoir waste, Agro by-products, Nutritive content, Bioavailability
INTRODUCTION
Pigs (Sus scrofa) are monogastric animals that are versatile, resilient, polyestrous, and prolific. They can be
raised under extensive, intensive, or semi-intensive management systems and are excellent feed-to-body
weight converters with a high dressing percentage compared to other domestic animals. Pig farming is
therefore a vital component of the global livestock industry, contributing to food security, employment, and
income generation [1].
Feed, which accounts for up to 70% of total production costs, is the most critical determinant of pig
productivity [2].
However, conventional feed ingredients such as maize and soybean are also used by humans and the feed
industry, creating strong competition and driving up costs [3]. In Nigeria, the scarcity and high cost of these
ingredients have become a major obstacle to the industry’s growth, threatening farmers’ profitability and even
pushing some out of production [4]. This has serious implications for income generation, employment, and
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
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food supply.
Protein is particularly important in animal diets. According to the World Health Organization, protein should
account for 10–15% of daily calorie intake. To meet this demand in livestock production, researchers have
increasingly focused on identifying alternative feedstuffs that can replace conventional ingredients without
compromising performance [5]. Agro-industrial by-products not intended for human consumption offer a
promising solution. Their use can reduce production costs, minimize food–feed competition, and improve
sustainability in livestock production [6].
Such by-products include residues from fruit, vegetable, grain, legume, and oil processing [7]. Common
examples are palm kernel cake (PKC), brewers’ dried grain (BDG), and wheat offal. PKC, a co-product of
palm oil extraction, contains about 15.73% crude protein and 58.53% total digestible nutrients, making it a
useful protein and energy source [8]. With palm kernel oil processing yielding about 45% PKC, its supply is
sustainable [9], although inclusion at high levels may reduce feed intake and growth performance in pigs.
BDG, another by-product, is rich in crude protein (19–25%) and fiber (10–22%), though its nutrient
composition varies with brewery source [10–13]. It also contains minerals, vitamins, and amino acids [15].
Similarly, wheat offal, a by-product of flour milling, is high in fiber and contains 14–17% crude protein [16].
Although its non-starch polysaccharides are poorly digested by monogastric animals, enzyme supplementation
has been shown to improve utilization [17,18].
Abattoir by-products such as rumen content (RC) also have potential as livestock feed. Although often
discarded as waste, rumen content is rich in energy, minerals, and B vitamins [19,20], and has been identified
as a possible ingredient in pig diets [21]. Its utilization could reduce feed costs while addressing environmental
pollution associated with abattoir waste disposal.
The high cost of conventional ingredients such as fish meal, groundnut cake, and soybean meal remains a
major constraint in pig production. This forces farmers to underfeed animals, thereby limiting growth and
productivity. Exploring alternative protein sources from agro by-products and abattoir wastes is therefore
essential to reducing production costs, enhancing sustainability, and improving pork quality. This study aims to
evaluate the nutrient composition and bioavailability of selected abattoir wastes and agro by-products in
weaner pigs.
MATERIALS AND METHODS
Location of the Experiment
The experiment was conducted at the Swine Unit of the Teaching and Research Farm of the Faculty of
Agriculture and Poultry Meat Laboratory of the Department of Animal Sciences; Obafemi Awolowo
University, Ile-Ife, Nigeria.
Materials
Several materials were used in this study including: Weaner pigs, Palm kernel cake meal, Cattle Blood meal,
Rumen Content, Salt, Brewer dried grain, wheat offal, Vitamin prefix, H2SO4, NaOH, H2BO3, HCL, Petroleum
ether, Phenolphthalein indictor. Meanwhile, the tools used were trash bags, sample storage containers, shovels,
latex, masks, disk mill machines, analytical scales, ovens, Muffle furnace, desiccators, Whatman 41 filter
paper, oil paper, centrifuges, film tubes, Conway dishes, biuret, glass beaker, measuring pipette, micro burette,
special distilled flask, destruction flask, scissors, blender, plastic tray, label, stove, and stationery.
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
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Preparation Stage
Bovine blood and Rumen content (RC) was collected from the AteridaAraromi Abattoir, along Ede Road,
Olowe’s Abattoir, lagere and Oriloye alias Titi Tunde slaughter slab, along Ibadan Road, campus gate. All the
agro-industrial byproducts (BDG, PKC, and WO) were obtained from a reputable feed mill within Ile-Ife.
Bovine blood was collected daily into a 10 litres keg containing predetermined amount of table salt to avoid
coagulation. Using the protocol from [22], 18g of salt per Kg of blood was used. This quantity of salt provided
enough time for the BDG, PKC and; WO to be added individually and hand mixed at ratio 1:1 with the
collected bovine blood. For the RC, it was emptied into a woven sack and dewatered. The bovine blood-RC
mixture was hand-mixed thoroughly using ratio 2:1. The mixtures were then sundried for 3 to 4 days under
direct sunlight to about 10% moisture content. These were packed separately and stored for later use.
Management of Experimental Diet
Fifteen crossbred (Large White x Hampshire) pigs with average initial weight of 10.00 Kg were used for the
experiment. The animals were randomly assigned to 5 experimental diets. There were 3 pigs per treatment and
each of them served as replicate and was housed in a metabolism cage for a seven-day period. Before the
commencement of the experiment, all animals were given antibiotics. Other routine management practices
were strictly adhered to. Feed and water were supplied ad libitum to animals throughout the experiment. The
first four days was for adaptation to the diets while the remaining three days was for faecal collection for the
determination of nutrient bioavailability.
Experimental Diet
Five experimental diets were formulated to contain five different test ingredients at 99.5% inclusion level. Diet
1 contained 99.5% of Groundnut cake (GNC), while diet 2,3,4 & 5 contained 99.5% of Rumen content and
blood meal (RC-BBM), Palm kernel Cake and blood meal (PKC-BBM), Wheat Offal and Blood meal (WO-
BBM), and Brewer Dried Grain and Blood Meal (BDG-BBM) respectively (Table 1). Experimental diets were
fed to the animals on treatment basis ad libitum. Water was also supplied ad libitum throughout the
experimental period
Method and Research Design
The method used in this research includes research design, preparation stage, Feeding Trial and Digestibility
Study, data collection and data analysis. A Completely Randomized Design (CRD) was employed for this
study, involving 5 dietary treatments with 3 replications each, making a total of 15 weaner pigs (Large White ×
Hampshire crosses) with an average initial body weight of 10.00 kg.
Data Collection and Chemical Analysis
The last 3 days of the experiment were designated for total excreta collection. Feed intake was measured daily
by subtracting feed refused from feed offered. excreta output was collected daily, weighed, and stored under
refrigeration at 4°C. The analysis phase includes proximate analysis and Apparent nutrient digestibility of
Agro by-products and abattoir waste by weaner pigs. Each diet was analyzed for proximate composition. The
analysis for dry matter, crude protein, crude fibre, ether extract, Ash and Nitrogen free extract was done
according to the method of [23] in the Laboratory.
The Apparent digestibility was determined using the proximate composition of the diets and excreta sample
using the equation:
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
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Apparent Nutrient Digestibility (%)
= (Nutrient intake − Nutrient in faeces) × 100
Nutrient Intake
Data Analysis
Data were analysed using One-way Analysis of Variance (ANOVA) using the GLM procedure of [24] while
means were separated using Duncan Multiple Range test at 5% significant level.
Table 1: Composition Of Diet Fed To Weaner Pigs
Ingredient Diet
1
Diet 2 Diet 3 Diet 4 Diet 5
GNC (Groundnut Cake) 99.50 – – – –
RC-BBM – 99.50 – – –
PKC-BBM – – 99.50 – –
WO-BBM – – – 99.50 –
BDG-BBM – – – – 99.50
Vitamin Premix 0.25 0.25 0.25 0.25 0.25
Salt 0.25 0.25 0.25 0.25 0.25
Total 100 100 100 100 100
Each diet contained a primary protein source: Diet 1: GNC: Groundnut cake; Diet 2: RC-BB: Rumen content
and Bovine blood; Diet 3: PKC-BB: Palm kernel cake and Bovine blood; Diet 4: WO-BB: Wheat offal and
Bovine blood; Diet 5: BDG-BB: Brewers’ dried grain and Bovine blood. All diets included 0.25% vitamin
premix and 0.25% salt.
RESULTS
Proximate Composition of the experimental diet
The proximate composition of diets fed to animals is shown in Table 2 below, the result showed varied
composition of dry matter content, crude fibre, crude protein, ether extract, ash, nitrogen free extract content.
The dry matter content of the experimental diets varied between 94.23% to 90.12%. The lowest and highest
values were found in diets 1 (90.12%) and 4 (94.23%) respectively. The crude fibre content ranged from
6.01% to 9.45%. Diet 1 had the least (6.01%) while diets 3 had the highest crude fibre content (9.45%). The
crude protein content varied between 38.51% to 45.87%. The lowest and highest values were found in diets 1
(38.51%) and 5 (45.87%) respectively. The ether extract content ranged from 3.43% to 8.53%. Diet 5 had the
lowest ether extract (3.43%) while diet 1 has the highest (8.53%). The ash content varied between 6.01% to
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20.02%. Diet 1 the lowest ash content (6.01%) while diet 2 has the highest (20.02%). The nitrogen free extract
content of the diets varied between 22.97% to 29.47%. The lowest and highest values were found in diets 3
(22.97%) and 1 (29.47%) respectively.
Apparent Nutrient digestibility of Agro by-products and abattoir waste by weaner pigs.
The apparent nutrient digestibility coefficient is shown in Table 3 below. The dry matter content was highest in
diet 3 (95.32%) and least in diet 5 (90.65%). Pigs on diet 1 had the better crude fibre digestibility (25.35%)
while those fed diet 3 had the least (14.01%). Also, pigs fed diet 3 had the best crude protein digestibility
(28.29%) while those fed diet 2 had the poorest (20.18%). The ether extract content was highest in diet 1
(4.68%) and least in diet 2 (0.12%). Pigs fed diet 9 had the best ash digestibility (15.35%) while those fed diet
3 had the poorest (8.68%). Also, pigs on diet 3 had the better nitrogen free extract digestibility (43.60%) while
those fed diet 5 had the least (29.03%).
Table 2: Proximate Composition Of The Experimental Diet
Parameter (%) Diet 1 Diet 2 Diet 3 Diet 4 Diet 5 SEM P-Value
Dry matter 90.12 93.68 92.00 94.23 91.43 4.83 <0.0001
Crude fibre 6.01 8.27 9.45 7.11 6.89 5.19 <0.0001
Crude protein 38.51 44.51 43.12 42.87 45.87 0.73 <0.0001
Ether extract 8.53 5.79 4.32 4.01 3.43 0.86 <0.0001
Ash 6.01 20.02 16.32 18.58 15.01 0.87 <0.0001
NFE 29.47 23.47 22.97 26.11 23.11 0.81 <0.0001
Each diet was formulated with a distinct primary protein source: diet 1 = groundnut cake (GNC); diet 2 =
rumen content and bovine blood (RC-BB); diet 3 = palm kernel cake and bovine blood (PKC-BB); diet 4=
wheat offal and bovine blood (WO-BB); diet 5= brewer dried grain and bovine blood (BDG-BB). Significant
differences observed across all parameters (P < 0.0001). SEM = Standard Error of Mean.
Table 3: Apparent Nutrient Digestibility Of Agro By-Products And Abattoir Waste By Weaner Pigs
Parameter (%) Diet 1 Diet 2 Diet 3 Diet 4 Diet 5 SEM P-value
Dry matter 93.32
ᵃᵇ
93.32
ᵃᵇ
95.32ᵃ 91.32
ᵇ
90.65
ᵇ
0.53 0.0332
Crude fibre 25.34
ᵃ
24.01
ᵃ
14.01ᶜ 16.68
ᵇ
18.02
ᵇ
0.72 <0.0001
Crude protein 20.18
ᶜ
20.42
ᵈ
28.29ᵃ 25.49
ᵇ
26.84
ᵇ
0.49 <0.0001
Ether extract 4.68ᵃ 0.12ᶜ 0.74ᵇᶜ 0.74ᵇᶜ 1.14ᵇ 0.29 <0.0001
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Ash 10.68
ᵇ
14.67
ᵃ
8.68ᵇ 14.68
ᵃ
15.35
ᵃ
0.58 <0.0001
NFE 30.44
ᵇᶜ
34.10
ᵇ
43.60ᵃ 33.73
ᵇ
29.03
ᶜ
0.50 <0.0001
Values are means of triplicate determinations. Superscripts (a, b, c, d) within the same row indicate significant
differences (P < 0.05) according to Duncan’s Multiple Range Test. SEM = Standard Error of Mean. NFE =
Nitrogen-Free Extract.
DISCUSSION
The present study investigated the potential of abattoir waste and agro-industrial by-products as alternative
feed sources for weaner pigs. Specifically, the study focused on assessing the nutrient composition and
bioavailability of these unconventional feed ingredients when incorporated into the diets of weaner pigs, as
well as their comparative efficiency against conventional feedstuffs like groundnut cake (GNC).
The results of this experiment provide valuable insights into the role of such feed resources in enhancing the
sustainability and cost-effectiveness of pig production in Nigeria and other regions where the high cost of
conventional feed ingredients is a major concern.
This discussion contextualizes the findings of the study in relation to the nutritional profiles, digestibility, and
potential application of these feed resources in swine nutrition.
Proximate Composition of Experimental Diets
The proximate analysis revealed significant variations in the nutrient content across the experimental diets,
which were formulated using five different feed ingredients: Groundnut Cake (GNC), Rumen Content and
Bovine Blood Meal (RC-BBM), Palm Kernel Cake and Bovine Blood Meal (PKC-BBM), Wheat Offal and
Bovine Blood Meal (WO-BBM), and Brewers Dried Grain and Bovine Blood Meal (BDG-BBM).
These results suggest that the feed ingredients sourced from agro-industrial by-products and abattoir waste
have the potential to provide a diverse range of essential nutrients, although their profiles may vary
significantly depending on the source.
The dry matter (DM) content, a key parameter in determining the overall nutrient density of feed, ranged from
90.12% in the GNC-based diet (Diet 1) to 94.23% in the WO-BBM-based diet (Diet 4). This finding is
consistent with previous reports showing that agro-industrial by-products such as wheat offal and brewers'
dried grains generally exhibit high DM content [25]. The high DM content in Diet 4 could be attributed to the
relatively low moisture content of wheat offal compared to other by-products like BDG and PKC. A higher
DM content typically implies a more concentrated nutrient source, making the feed more efficient in terms of
energy and nutrient delivery per unit of intake.
The crude protein (CP) content of the diets ranged from 38.51% in the GNC-based diet (Diet 1) to 45.87% in
the BDG-BBM-based diet (Diet 5). The high protein content in Diet 5 can be explained by the use of brewers'
dried grain, which is known for its relatively high protein content [26]. The elevated protein levels in Diet 5
suggest its potential for supporting growth and muscle development in pigs.
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Additionally, the protein quality of these agro-industrial by-products could be enhanced by their combination
with bovine blood meal, which is rich in essential amino acids. However, it should be noted that protein
digestibility can vary depending on the specific feed ingredient and its level of inclusion, as discussed below.
Moreso, the crude fibre content was found to be highest in the PKC-BBM-based diet (Diet 3), with a value of
9.45%. This is consistent with the known composition of palm kernel cake, which considered as a high fiber
co-product [27]. While crude fibre is essential for promoting gut health and aiding in the prevention of
constipation, excessive fibre levels in swine diets may lead to reduced feed intake and growth performance
[25]. Therefore, a careful balance of fibre content is necessary to optimize the growth performance of weaner
pigs, especially when incorporating high-fibre agro-industrial by-products.
The ether extract (EE) content, which is indicative of the fat content of the feed, was highest in the GNC-based
diet (Diet 1, 8.53%). This high fat content may be beneficial for providing the necessary energy required for
growth and development in young pigs. However, diets that are too high in fat can negatively affect feed intake
and nutrient absorption [28]. The lower fat content in the other diets, such as the BDG-BBM-based diet (Diet
5), may suggest that these feed ingredients are more energy-dense due to their relatively higher carbohydrate
content, which is also reflected in the nitrogen-free extract (NFE) values.
Additionally, ash content, which provides an estimate of the mineral content in the feed, was highest in the
RC-BBM-based diet (Diet 2, 20.02%). This is likely due to the mineral-rich nature of rumen content, which
contains significant levels of calcium, phosphorus, and trace minerals essential for bone development and
overall health in pigs. The relatively high ash content in Diet 2 highlights the potential of rumen content as a
valuable source of minerals, although the impact of such high mineral levels on nutrient balance and pig health
requires further investigation.
Apparent Nutrient Digestibility
The apparent digestibility of the nutrients was assessed by measuring the difference between nutrient intake
and nutrient content in the faeces. The digestibility of dry matter (DM) varied significantly across the diets,
with the highest digestibility observed in the PKC-BBM-based diet (Diet 3, 95.32%) and the lowest in the
BDG-BBM-based diet (Diet 5, 90.65%). This finding aligns with previous studies indicating that palm kernel
cake, when properly processed, is highly digestible and well-utilized by monogastric animals like pigs [25].
The high DM digestibility in Diet 3 suggests that palm kernel cake may be a superior ingredient for optimizing
feed efficiency in weaner pigs compared to other agro-industrial by-products.
The digestibility of crude fibre was highest in the GNC-based diet (Diet 1, 25.35%), suggesting that the
relatively low fibre content of groundnut cake contributes to its higher digestibility. This result supports the
idea that low-fibre ingredients are more readily utilized by pigs, particularly during the early growth phase
when energy and protein requirements are critical. In contrast, the PKC-BBM-based diet (Diet 3) showed the
lowest crude fibre digestibility (14.01%), likely due to the high fibre content of palm kernel cake, which can
reduce nutrient utilization in pigs [27].
The crude protein digestibility was highest in the PKC-BBM-based diet (Diet 3, 28.29%) and lowest in the
RC-BBM-based diet (Diet 2, 20.18%). This indicates that pigs fed the PKC-BBM diet could better utilize the
protein derived from palm kernel cake and bovine blood meal, likely due to the superior protein quality and
amino acid composition of these ingredients. Studies have shown that the inclusion of palm kernel cake in pig
diets does not significantly impair nutrient digestibility and can maintain or even improve protein utilization
efficiency [29]. Furthermore, graded levels of bovine blood meal have been demonstrated to support good
growth performance, corroborating the high protein digestibility observed with PKC-BBM-based diets [30].
Conversely, the relatively low crude protein digestibility in the RC-BBM diet may be attributed to the inferior
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protein quality of rumen contents compared to other protein sources such as groundnut cake and brewers' dried
grain. Literature indicates that rumen content proteins are less digestible, which adversely affects the overall
protein utilization in pigs fed such diets [31]. These differences in ingredient quality likely underpin the
observed variation in protein digestibility across diets.
The digestibility of ether extract was highest in the groundnut cake (GNC)-based diet (Diet 1, 4.68%) due to
the high fat content of groundnut cake, which provides an easily digestible energy source for pigs. In contrast,
diets with more fiber-rich ingredients such as the PKC-BBM and WO-BBM diets showed significantly lower
ether extract digestibility. This reduction is primarily because dietary fiber interferes with fat absorption,
limiting the energy pigs can derive from these diets. Recent research confirms that higher fiber content
negatively affects fat digestibility and overall nutrient utilization in pigs, as fiber hinders the digestion and
absorption processes of fats. Moreover, variations in ether extract digestibility related to ingredient
composition have been documented across different feed sources, highlighting the importance of diet
formulation to optimize fat utilization [32, 33].
The digestibility of ash, which is a proxy for mineral absorption, was highest in the BDG-BBM-based diet
(Diet 5, 15.35%), suggesting that brewers' dried grain, in combination with bovine blood meal, may enhance
the availability of essential minerals like calcium and phosphorus for weaner pigs. This finding is particularly
important, as mineral deficiencies can impair growth and bone development in young pigs [26]. Finally, the
nitrogen-free extract (NFE) digestibility was highest in the PKC-BBM-based diet (Diet 3, 43.60%), which is
consistent with the higher carbohydrate content of palm kernel cake. Carbohydrates are an important energy
source for pigs, and the efficient digestion of NFE in this diet suggests that palm kernel cake may be an
effective energy-dense ingredient for weaner pigs [25].
Implications for Sustainable Pig Production
The findings of this study highlight the promising potential of incorporating abattoir waste and agro-industrial
by-products as cost-effective alternatives to conventional feed ingredients like groundnut cake in pig diets.
Utilizing these alternative feed resources can substantially reduce feed costs, which represent a major portion
of total production expenses in intensive pig farming systems. Research shows that abattoir and agro-food
wastes, rich in nutrients, can be repurposed as sustainable feed ingredients that help minimize waste disposal
costs and support circular economy approaches in animal production. However, the efficacy and safety of these
alternative feeds depend on factors such as inclusion rates and proper processing to maintain animal health and
performance. Overall, their use presents a viable strategy for lowering feed expenses while promoting
environmental sustainability in pig production [34].
Additionally, these alternative feed ingredients are more readily available and cost-effective, making them an
attractive option for farmers in regions where conventional feed ingredients are scarce and expensive [25].
Furthermore, the use of abattoir waste, such as rumen content, as a protein source in pig diets offers an
opportunity to reduce environmental pollution associated with the disposal of such waste products [35].
Properly processed and formulated, rumen content and bovine blood meal can provide essential amino acids
and minerals necessary for optimal pig growth, thereby contributing to a more sustainable and circular
approach to animal feed production.
In conclusion, the study demonstrates that abattoir waste and agro-industrial by-products are nutritionally
viable alternatives to conventional feed ingredients in the diets of weaner pigs. The findings indicate that these
alternative feed resources, when properly processed and formulated, can improve nutrient digestibility, support
growth performance, and enhance the sustainability of pig production systems. By utilizing these readily
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available, cost-effective ingredients, pig farmers can reduce feed costs while improving the quality and
quantity of pork production, thereby contributing to the economic and environmental sustainability of the
industry.
CONCLUSION
This study demonstrates that abattoir waste and agro-industrial by-products, including rumen content, palm
kernel cake, wheat offal, brewers' dried grain, and bovine blood meal, can serve as valuable, cost-effective
alternatives to traditional feed ingredients like groundnut cake in the diets of weaner pigs. The proximate
composition analysis revealed significant nutrient variability among the diets, with certain by-products offering
high levels of crude protein, energy, and essential minerals. Importantly, the apparent nutrient digestibility
trials showed that these alternative ingredients were efficiently utilized by the pigs, with the palm kernel cake
and bovine blood meal combination (PKC-BBM) offering the highest digestibility of dry matter and crude
protein. The findings suggest that these agro-industrial by-products and abattoir wastes can support pig growth
and health when incorporated into diets, reducing the reliance on expensive conventional feedstuffs and
enhancing feed sustainability.
This approach not only offers a solution to the escalating feed costs in pig production but also promotes the
recycling of waste products, thereby contributing to environmental sustainability. The results of this study
highlight the potential for integrating these non-traditional feed resources into commercial pig farming,
providing a pathway to more affordable and sustainable animal protein production, with implications for both
economic and environmental gains in the agricultural sector.
ACKNOWLEDGMENT
I want to appreciate the support of Dr. Adeniji Adegboyega for his support towards the writing of this paper.
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