1. Introduction
The importance of the poultry industry in the Nigerian economy cannot be over-emphasized. The industry contributes about 25% of agricultural GDP to the Nigerian economy (CBN, 2019). Apart from employment generation, eggs, one of the products of poultry production, are more affordable for the populace sources of animal protein [
1,
2,
3]. Interestingly, egg consumption has jumped from 366,000 tons in 2000 to 598,000 tons in 2015, and projected to reach 947,000 tons by 2030. The poultry meat subsector has grown from 158,000 tons in 2000 to 317,000 tons in 2015, and projected to reach 544,000 tons by 2030 [
4]. However, despite the importance of the industry, various challenges of which cost of feed and others factors (high rate of disease and pest attack, lack of loan and credit procurement, lack of technical knowledge, high rate of mortality, supply of poor-quality chicks, inadequate poultry extension services, and inadequate access to and high cost of veterinary services) have prevented the industry from expected performance [
5,
6].
Feed alone accounts for 70% of the total costs in poultry production [
7]. The unabated increase in the price of poultry feed in Nigeria led to the high cost of maize, which constitutes between 50 and 60% of feed ingredients [
8]. According to Akinfenwa [
9], the price of maize thatwas NGN 80 (USD 0.22)/kg in March 2020, crept to NGN 180 (USD 0.22)/kg and NGN 260 (USD 0.69)/kg in August 2020 (the official exchange rate of dollars to naira in March 2020: USD 1 = NGN 364.55 and August 2020: USD 1 = NGN 378.49) and December 2021, respectively. As a result of the sharp increase in the price of maize, the cost of feed per bag also increased from NGN 3000 (USD 7.87) in March (the average official exchange rate of dollars to naira from March–April 2021: USD 1 = NGN 381) to between NGN 4600 (USD 12.07) and NGN 5300 (USD 13.91) in April. In December 2021, the price of 25 kg poultry feed ranged from NGN 5300 (USD 12.60)–NGN 7950 (USD 18.90) (the average official exchange rate of dollars to naira from March–April 2021: USD 1 = NGN 381), depending on the type and the brand of feed. Several reasons have led to the increase in the price of maize. These include a ban on the importation of maize used to augment the shortfall in the local supply, the problem of armyworm infestation, insecurity and climate change, among others [
10]. Financially viable poultry production in Nigeria is essential to keep the cost of protein (e.g., eggs) lower for consumers and is in line with the National Food and Nutrition Policy and Agricultural Food Security and Nutrition Strategy of the Federal Government [
11].
The consequence of the high cost of maize has resulted in higher poultry production costs and alteration of the finished poultry feed quality (commercial feed millers often do not meet the requirements of the animals due to the high cost of conventional feedstuffs). This leads to inadequate animal protein intake as a result of poor performance of the host animals fed with the poor-quality diets by some feed miller [
12]. According to Madubuike [
13], the high cost of feed has remained the major constraint facing poultry production in Nigeria because of the high percentage it accounts for in the total cost of poultry production. The poultry feed industry in Nigeria operates under monopolistic competition where each producer claims product differentiation from others in terms of content (quality) and package. It is a type of imperfect competition such that many producers compete against each other, but sell products that are differentiated to Top feed, Animal care, Chikun, Breedwell, New Hope, Vital and Hybrid, among others. Since these brands are differentiated from each other in the market based on quality and other attributes, the market is not perfectly competitive but rather monopolistically competitive [
14,
15]. According to Chron Contributor [
16], brand switching as an outcome of customer switching behavior describes customers/consumers abandoning a product or service in favor of a competitor. The high cost of feed encourages brand switching among poultry farmers.
With the ever-increasing cost of feed, the likelihood of the commercial egg producer switching to cheaper poultry feed that will make it possible to achieve the profit-maximization goal is becoming unrealistic. The consequence is that many egg farmer workers may opt out of egg production. This may lead to farmworkers losing their jobs. The inability of the remaining few commercial farmers to meet egg demand will increase the price. This would make eggs unaffordable for an average Nigerian. Prior research [
17] revealed that a medium-sized egg/crate was sold for NGN 1200 (USD 3.16) in November 2020. The price increased to NGN 1500 (USD 3.94) in March 2021 and is currently sold for NGN 1900 (USD 5.00). In the long run, at the detriment of food security, the pressure on the natural resources (soil and water) for the production of feed ingredients (maize, soybean, sorghum and groundnut) would decline. Tropical deforestation through various human activities, such as intensive crop farming, would not only lead to biodiversity loss and soil degradation, but deforestation is also responsible for significant amounts of greenhouse gas (GHG) emissions [
18,
19]. The expansion of arable land has driven growth in crop production rather than adoption of improved technology to enhance productivity [
20].
Many factors influencing brand switching have been identified in the literature. These include price, promotional activities, brand image, variety and packaging [
21,
22,
23,
24], involvement [
25,
26] and dissatisfaction [
25]. The effects of an increase in the price of poultry feed include: a reduction in the number of poultry farmers, the emergence of different poultry feeds that may be marginally cheaper than others, increase in the price of poultry products regarded as a cheap source of protein (egg and chicken), which makes it out of reach for the high percentage of the populace, as well as losses of jobs and livelihoods [
27,
28,
29]. Manipulation of feed ingredients by the feed millers, use of synthetic amino acids, control of feed wastage, enzyme supplements, use of flavors and sourcing for cheap poultry feed are some of the coping strategies being adopted by poultry farmers to cope with the increasing cost of feed [
30].
Consumer brand switching behavior has been researched in several studies in the mobile telecommunications, cosmetics, toothpaste, soft drink and banking industries [
30,
31,
32]. Past studies on poultry feed [
33,
34,
35,
36,
37,
38] have concentrated on profitability analysis, quality of poultry feed, alternative feedstuff and marketing. Our study’s aim is to address the gap in the literature on the brand switching of poultry feed among egg producers in southwest Nigeria, which is the nation’s poultry production hub. Here, brand switching is a coping strategy to adapt to higher poultry branded feed prices by commercial egg farmers.
The poultry industry is concentrated in southwest Nigeria, which is a geopolitical zone over six decades old with a poultry population that has steadily grown to 30 million or 60% of the national flock [
9]. Our study is timely because the current increases (almost weekly) in the cost of feed has forced many farmers out of business and remaining farmers are searching for coping strategies that would keep them in business. There is a dearth of literature on feed brand switching by poultry farmers unlike other commodities, such as mobile phones, beer, gin, toilet soaps, etc. Therefore, this study seeks to fill these gaps and also provide answers to the following research questions: What are the socioeconomic characteristics of egg farmers/farms and poultry feed sellers in southwest Nigeria? What is the extent of market concentration in the sales of poultry feed in the study area? What is the pattern of brand switching of poultry feed among commercial egg-producing farmers? What are the factors influencing brand switching of poultry feed and the proportion of feed used in the long run by commercial egg-producing farmers? What are the implications of brand switching of poultry feed in the community? Evidence and recommendations from this study are important for policy trajectories and the development of the poultry industry in Nigeria, which enhances and ensures the possibility of household dietary diversity.
2. Theoretical Framework and Literature Review
Production and rational choice theories support our study. Production involves the combination of various material and immaterial inputs (plans, know-how) to produce something for consumption (the output). In the egg production business, feed, day-old chicks, drugs and depreciation on fixed items (the pen, cage, feeder, drinkers, wheelbarrow and shovel, among others) constitute production inputs, while the eggs are the output. Rational choice theory states that individuals use calculations to make rational choices and achieve outcomes in agreement with the objectives [
39]. This theory is associated with maximizing an individual’s self-interest. Using rational choice theory is expected to result in outcomes that provide people with the greatest benefit and satisfaction, given the limited option they have available. Many mainstream economic assumptions and theories are based on rational choice theory. Rational choice theory is associated with the concepts of rational actors, self-interest and the invisible hand [
39,
40]. As an entrepreneur, the motive of a commercial egg farmer is to have good returns on the amount invested through profit maximization. One of the ways to achieve this is to ensure low mortality and having access to quality feed feeds (Chikun, Top, Hybrids and Animal Care, among other brands) at a price that will not undermine profit. This is because feed costs are 60–70% of the cost of egg production. While egg farmers may not influence the cost of poultry feed per bag in the market, they can opt for cheaper poultry feed if their preferred brand of feed is costly [
41].
In the literature, Herfindahl–Hirschman, Linda and Horwath indices approaches are methods used to measure the market concentration or of the extent of inequality in the market shares in a particular sector. However, HHI shows sensitivity to firm size, while the Linda index is based on the distribution of the largest firms, not the entire distribution within the sector. It is difficult to find the data required for the estimation of the Horwath index, especially the marginal cost [
42]. The Lorenz curve and Gini coefficient were used in this study to measure the extent of market concentration in branded poultry feed. The Lorenz curve is an absolute measure of concentration in which firm size inequality is represented by the convexity of the curve [
43]. The Gini coefficient was calculated from the Lorenz curve and this measures the magnitude of the area between the Lorenz curve and the absolute equation line. This area reflects the proportional effect of the firm’s size and control share [
42]. The Lorenz curve shows how the variable of interest is distributed among the population. It produces an alert for monopoly emergence.
Several methods (Autoregressive Integrated Moving Average (ARIMA); exponential smoothing and simultaneous equations) have been used in the literature for forecasting. The ARIMA model has been used to make future predictions and this model uses time-series data [
44,
45]. One of the limitations of the ARIMA model is that the parameters (p, d and q) need to be manually defined. Therefore, finding the most accurate fit can be a lengthy trial-and-error process. The exponential smoothing model has also been used, but it does not recognize seasonal patterns and cannot project trends [
46,
47]. Simultaneous equation models have also been adopted in many studies [
48,
49,
50,
51]. The limitation of this method is that the two-stage least squares (2SLS) estimator is just the ratio of two covariances and it has weak instrumental variables. The 2SLS or general instrumental variables estimator does not exist and is inconsistent. Generalized method of moments (GMM) parameter estimates are usually measured with more errors. GMM estimates have the limitation of small sample properties.
A Markov chain model was used in this study since two consecutive periods were considered (brand of feed in use during data collection and the brand of feed used six months before data collection). A Markov chain or Markov process is a stochastic model describing a sequence of possible events in which the probability of each event depends only on the state attained in the previous event [
52]. The state of probabilities at a future instant given the present state of the process does not depend on the state it occupied in the past. Markov chain models have been extensively used in brand switching studies [
53,
54,
55,
56,
57]. Markov models are generalized and the generated sequences look similar to a sample of the real usage as long as the model captures the operational behavior. The analytical theory of the Markov chain model presumes a formal stochastic process [
58].
Analytical Frameworks of the Markov Chain Model
The theory of Markov process assumes the existence of a physical system
S, which has a number of possible systems,
S1,
S2, …,
Sn, and which at each instant of time can be in one of these states. The time after each successive trials can be denoted by
t0,
t1,
t2, …,
tn, with
t0 representing the starting point in time,
t1 as the time of conducting the first trialfor Markov chain; the probability of passing to some state
S1 at a given time depends on the state that the system was at the preceding time and does not change if you know what the states were at the earlier times. In the Markov chain,
Pij is used to denote the transition from one state to another (
i to
j). The probability transition matrix can be simplified as:
To forecast the proportion of the variable of interest at time
k:
where:
p(k) represents the probability transition matrix at time k, and
p(0) represents the probability transition matrix (PTM) at the initial or time zero (0).
At the equilibrium or steady state, the proportion of variable of interest is equal to the proportion multiplied by the PTM given as:
where:
e can be 1 × 2 when PTM is 2 × 2, 1 × 3 when PTM is 3 × 3, 1 × 4 when PTM is 4 × 4, etc.
p istheprobability transition matrix.
For 3 × 3 PTM,
e = ep is given as:
This gives three equations:
The total equation from
e = ep is four (4). Solving the system of equations for the
es produce the required equilibrium probability vector. However, it should be noted that the system of equations provides a set of n + 1 equations. That is, the equations are more than the unknowns—four equations with three unknowns. This shows that one of the equations (first three) is not linearly independent of the others. Therefore, one of the firstthree equations can be removed (assuming Equation (11) is removed) to presentthree equations with three unknowns as:
The solution to the system of equations producesthe equilibrium probability vectors of e1, e2 and e3.