Performance, Egg and Serum Biochemical Constituents of Four Commercial Pullet Strains in Nigeria

Performance, Egg and Serum Biochemical Constituents of Four Commercial Pullet Strains in Nigeria

Oyewole, Yusuf Olayinka; Akinsola, Kehinde Luke; Safiyu, Kamaroudeen Kolawole

Department of Animal Production, Lagos State University of Science and Technology, Ikorodu, Lagos State

^*Corresponding author

DOI: https://doi.org/10.51584/IJRIAS.2025.100600112

Received: 13 March 2025; Accepted: 20 March 2025; Published: 16 July 2025

ABSTRACT

The aim of this research was to evaluate the performance and biochemical constituents of egg and blood of four commercial pullet strains in Nigeria with specific reference to Isa Brown, Bovan Nera, Goldline Nera and Dominant Black. Pullet chicks of foreign origin whose parents were raised in Nigeria were used for this study. A total of 300 pullet chicks were used, comprising seventy-five (75) Bovans Nera, Seventy-five (75) Bovans Goldline, Seventy-five (75) Dominant Black and Seventy-five (75) Isa Brown from day old. The birds in each treatment were randomly grouped into three replicates per treatment. Replication was done to equalize the mean initial live weight. Analyzed result showed that Isa Brown and Dominant Black values were significantly (P<0.05) higher than that of Bovans Goldline, Bovans Nera for the pre-production performance characteristics of the strains of birds, however, the final live weight was highest (P<0.05) in Bovans Nera, (1272.00g) while that of the rest three strains were similar (P>0.05) (1245.67 g – 1248.33 g). Bovans Nera had the best live weight at 18 weeks, Bovans Nera and Bovans Goldline recorded the best FCE at 18 weeks, these may be an advantage to producers of point of lay, Mortality to point of lay was lowest in Dominant Black, Egg production to 30 weeks of age was best in Isa Brown and Dominant Black, Shell thickness and Egg shape index which is very important in egg sales and transportation is also best in Isa Brown, Cholesterol was lowest in Isa Brown. The study revealed differences in performance production characteristics and egg and serum biochemical indices, hence the best strain regards to the indices is Isa Brown, then Bovans Nera, Dominant Black and Bovans Goldline respectively.

Keywords: Genotype, Bovan Nera, Goldline Nera, Dominant black, Isa Brown.

INTRODUCTION

In a developing country such as Nigeria, there is a general awareness of the “Protein gap “in the human diet. This gap denotes the inadequacy of animal protein consumed by the average Nigerian. The average person consumes 45.4g against 53.8g which the World Health Organization (WHO) recommended (FAO/IFAD, UNICEF, WFP and WHO, 2019). This can be largely and rapidly bridged by the intensive production of domestic fowl. Many countries have adopted the domestic fowl as a means of economic empowerment due to the quick returns on capital investment arising from the short generation interval of the birds which makes it attractive to entrepreneurs (FAO, 2003b). Demand for meat and meat products is increasing daily due to the increased need for animal protein by the populace. Meat is a good source of protein which is required for growth, body tissue development, replacement of worn-out tissues, blood production, and body system maintenance and as a component of the immune system of the body (Aletor, 1983; Ahmad et al,, 2018). The availability of animal protein sources such as fish, meat, milk and poultry is limited by the high cost of animal production, Feed accounts for about 70% of the cost of production cost of monogastric animals (Aletor, 2000).

The supply of good quality chicks to producers as a measure towards improving the poultry sector has been emphasized (Fatuga, 1977; Geidam et al,, 2007). Also, Okon and Ekpenyong (1997) pointed out that there has been a lack of good quality hatchable eggs and highly productive indigenous parent stock and these have contributed to the inadequacy of day-old chicks supplied. Due to the proliferation of local franchise hatcheries in the country, there has been an increased supply of day-old chicks imported from different breeders companies abroad who breed different exotic breeds of chicken, like Isa Brown, Bovans Nera, Bovans Goldline, Dominant Blue, Dominant Black, Harco, Shaver Star Cross etc (Asuquo et al,, 1992; Emmanuel-Ohagenyi and Simeon, 2023). Unfortunately, there is a lack of adequate information on the choice of stock by producers in Nigeria on the qualities of the birds (Oluyemi, 1998; Akintunde, 2015). Egg production is the major index to measure the performance of commercial layers, it accounts for about 90% of the income in egg production, and other characteristics include egg size, egg quality, body weight, the efficiency of feed utilization and mortality (Hesham and Tamer, 2012).

There are two major approaches to the improvement problem. i.e. genetic improvement and environmental improvement. Genetic improvement has been greater for egg layers than any class of livestock except broilers. This resulted from improvement in four components of production, this includes, age at first egg, peak performance, sustained rate of lay and livability. The environmental factors affecting performance include nutrition, temperature, relative humidity, ventilation, stocking rate, pathogens, pollutants, stress, light and diseases (Oluyemi and Robert, 2000). The two important criteria of pullet quality are uniformity within and proper body weight at a specific age (Richard and Jackqueline, 2008). The aim of this research was to evaluate the performance and biochemical constituents of egg and blood of four commercial pullet strains in Nigeria with specific reference to Isa Brown, Bovan Nera, Goldline Nera and Dominant Black.

MATERIALS AND METHODS

Experimental Location

This study was conducted at the Teaching and Research Farm, College of Agricultural Sciences, Olabisi Onabanjo University, Yewa Campus, Ayetoro. The site is in Yewa North Local Government, a derived savanna zone, of Ogun state, Nigeria.

Experimental Animals

Pullet chicks of foreign origin whose parents were raised in Nigeria were used for this study. A total of 300 pullet chicks were used, comprising seventy-five (75) Bovans Nera, Seventy-five (75) Bovans Goldline, Seventy-five (75) Dominant Black and Seventy-five (75) Isa Brown from day old.

The strains and their origin are as follows:

(i) Bovans Nera and Goldline – Netherlands,

(ii) Isa Brown- France

(iii) Dominant black – Czech Republic.

Experimental birds and management

The birds were housed in the Teaching and Research farm. The pen was thoroughly cleaned and disinfected with disinfectant, and wood shavings were used as litter material. Feeders and drinkers were provided and charcoal pots and lanterns served as heat and light sources respectively. The open sides of the house were covered with polythene to conserve heat during the brooding phase.

Commercial feed was used throughout the trial and this consisted of chicks mash, growers mash and layers mash. The proximate composition of the feeds was determined (A.0.A.C., 2023).

All routine health management practices of vaccination, medication and deworming were observed and feed and water were offered ad libitum.

During the brooding phase which lasted for four weeks, the birds were grouped into four treatments, each breed representing a treatment, but after week four, the birds in each treatment were randomly grouped into three replicates per treatment. Replication was done to equalize the mean initial live weight. The replicates were randomly assigned to pen as A1, A2, A3 for Isa Brown, B1, B2, B3 for Bovans Nera, C1, C2, C3 for Bovans Goldline and D1, D2, D3 for Dominant Black.

Data Collection

The data collected/computed during the experiment were:

(i) Average weekly growth rate

The growth rate was determined as the difference in body weight taken before each of the weeks.

(ii) Weekly feed intake

Feed intake was determined weekly as the difference between feed offered for the week i.e. Total feed consumed per week/no of birds.

(iii) Feed conversion ratio

Computed as feed intake (g) per body weight gain (g) and feed intake (kg) per kg egg layer.

(iv) Mortality

Mortality was computed in three phases i.e. brooding phase, growing phase and laying phase.

(v) Age at first egg, Age at 5% production, Egg production record (hen day production %)

(vi) Egg weight per strain (weekly) using sensitive scale

(vii) Egg shape index

The egg width and egg length were measured with a vernier calliper. The unit of measurement was a millimetre.

Shell thickness

A micrometre screw gauge was used and the average of these was taken as the shell thickness.

Chemical Analysis

Diets AOAC, (2023)

Proximate analysis of experimental diets was done in the laboratory (Table 3)

CP Crude protein, EE ether extract, CF= crude fibre, MC= moisture content, DM= dry matter, CA= calcium, P= phosphorus.

Eggs And Serum Biochemical Parameters

At weeks 24 and 30, blood samples (5ml) were taken into plastic tubes containing anti-coagulant ethylene diamine tetra-acetic (EDTA) for the determination of haematological parameters. Serum protein was determined using the Biuret method (Reinhold, 1995). Albumen fat was estimated by [Bayoumi et al (1986)] fatty acid (Pearson, 1980). Total cholesterol in eggs (Embert, 1974). Calcium and Phosphorus, Preer and Rosen, (1977).

Statistical Analysis

The data obtained were subjected to analysis of Variance using the general linear model (GLM) procedure (S.A.S, 2000). Significant means were separated using the Duncan Multiple Range Test.

RESULTS AND DISCUSSION

Pre-production performance characteristics of the strains of birds

There was significant (P<0.05) difference for the mean initial live weight among the strains of birds. Isa Brown and Dominant Black values were significantly (P<0.05) higher than that of Bovans Goldline, Bovans Nera.

Table: Performance characteristics of different strains of birds (0-18 weeks)

a,b,c Means along the same row followed by different superscripts are significant (P<0.05) SEM

The final live weight was highest (P<0.05) in Bovans Nera, the final live weight for the other three strains are however similar P<0.05). These results for live weight gain followed the same trend as that of the final live weight since the birds were subjected to the same management conditions, the result on live weight agrees with Siegel (1978); Crawford (1990) and Xiang et al., (2023) that genetic factors are involved in growth/live weight changes.

Bovans Nera had the highest (P<0.05) weight gain (1272.00g) while that of the rest three strains were similar (P>0.05) (1245.67 g – 1248.33 g). The differences that occurred between the strains on live weight (g) and live weight gain (g) could be due to the effect of genetic differences and adaptability to environmental conditions (Oluyemi and Roberts 1979, 2000; Myles and Tanja, 2006). The mean feed intake between the strains was significantly (P<0.05) different, the highest feed intake was recorded by Dominant Black (402.50g), while the Bovans Goldline recorded the lowest (384.05g) feed intake. Feed intake was comparable (P<0.05) between Isa Brown and Bovans Nera and values were intermediate of the other two strains. The differences in the quantity of feed consumed can be attributed to different factors. Feed intake could also be influenced by body weight or size as stated by Rose (1997) and Junjie et al, (2024). Birds eats a daily amount of feed that is equivalent to approximately 5% of their body weight. The most efficient means of determining the optimum utilization of the feed of the strains is the feed conversion which was lowest (P<0.05) in Dominant Black. Feed conversion was equally lower (P<0.05) in Isa Brown than in Bovan Nera and Bovans Goldline which had comparable values. Chambers (1990) and Yan et al., (2024) reported that chicken that differs in productivity will have different nutrient feed efficiency and feed conversion ratio and that there is genetic basis with breed and strain differing in nutrient requirements. Fast-growing chickens convert feed into body weight more efficiently than their slow-growing counterparts and many of the same genes that cause fast growth, also make for more efficient gain (Oluyemi and Roberts 2000). Baxter et al., (2021) reported that fast-growing chickens make more efficient gains than slow-growing chickens because they use a small percentage of their feed intake for maintenance and have a more efficient metabolic system which allows for a better utilization of feed. All these could result in variations of feed efficiency among the strains. The last indices of the performance characteristics still In the table is mortality, The mortality recorded between weeks 0 and 18 showed a significant difference (P<0.05) with Dominant Black being more resistant and hardy to diseases with the least mortality (1.33%) the intermediate groups were Isa Brown and Bovans Nera but the least tolerant was Bovans Goldline since they were all subjected to the same input (feeding, health management and environment etc) The post mortem shows signs of Newcastle disease and traces of intestinal Coccidiosis. The percentage mortality recorded for the strains falls short of the range of 10% at 21 weeks recommended by Oluyemi et al., (1997).

Production Performance

The mean production performance indices of four different strains of laying hen (19 – 30 weeks) are presented in the table below.

Mean Production Characteristics of Different Strains of Birds (19-30 Weeks)

a,b,c Means along the same row followed by different superscripts are significant (P<0.05) SEM = standard error of means.

The live production performance as presented in the table showed that the final live weight was comparable for Isa Brown, Dominant Black and Bovans Nera and values were significantly (P<0.05) higher than that of Bovans Goldline. However, there were significant differences in body weight gain between the strains (P<0.05). The differences that occurred between the strains on live weight (g) and live weight gain (g) could be due to the effect of genetic differences and adaptability to environmental conditions as stated in performance characteristics above.

This perhaps explains the trend observed in the live weight of the strains and agreed with Rose (1997) and Olawumi et al, (2012) who reported that feed intake could also be influenced by body weight or size, that poultry eats a daily amount of feed that is equivalent to approximately 5% of their body weight. Feed conversion efficiency was slightly higher across the strains, statistically, measurable differences (P<0.05) were observed. The trend observed in feed efficiency was only different in Isa Brown compared with other strains and they compared favorable. This could be due to possible genetic similarity among these strains, this corroborates the report of Crawford (1990b) that most of these modern strains have similar genetic make-up. Araujo et al, (2015) obtained a range of 2.69-2.97 for feed conversion for egg production measured as feed intake/egg mass production.

Bovans Nera had its first egg at 135 days of an egg; Isa Brown had its first egg at 138 days of age while Bovans Goldline and Dominant Black had theirs at 139 and 140 days respectively. These results contradict what is obtained in the literature. Ayorinde et al., 1988 and Jesuyon (2009) reported a point of lay at 151 days and 161 days of age for heavy-weight and light-bodied birds respectively, Essien (1994) obtained 159 days for age at first egg while Oluyemi and Roberts (2000) reported range of 20 – 24 weeks (140 -168 days).

The ages at 5% hen day production were significantly different (P<0.05) Isa Brown and Bovans Goldline’s age at 5% hen day production was at 152 days while Dominant Black and Bovans Nera reached 5% hen production at 141 and 144 respectively.

Dominant Black and Bovans Nera recorded the highest values in terms of final live weight gain, feed intake and feed conversion efficiency when compared to Isa Brown and Bovans Goldline and this contributed to the strains reaching 5% hen production earlier, this corroborates Crawford (1990) which stated that with appropriate environmental conditions (nutrition, light, ambient temperature, water, free from diseases).

Strain differences tend to affect the average hen-day production as significant differences exist between them (P<0.05) with Isa Brown and Dominant Black recording the highest value when compared to Bovans Nera and Bovans Goldline respectively.

The highest gain value was recorded by Isa Brown and Dominant Black over the Bovans Goldline and Bovans Nera this agreed with Oluyemi and Robert, (2000) that differences that occurred between the strains on live weight (g) and live weight gain (g) could be due to effect of genetic differences and adaptability to environmental conditions.

Total egg produced during the productive period follows the same trend as Hen day production while total feed intake is also aligned with feed intake (g) consumed during the productive period.

No significant (P>0.05) were found when comparing the strains during the laying period Oluyemi and Robert (2000) reported that the average egg weight of tropical domestic fowl is about 58g with a range of about 40g-70g Olayiwola (1988) obtained average egg weight of about 54g. The egg weight recorded in this research agreed with the range reported by Oluyemi et al., (2000).

The shell thickness was significantly (P<0.05) influenced by different strains. However, the thickness among all strains (0-547 – 0.541) which was recorded is still of higher value compared to what is being reported by Oluyemi and Roberts (2000) who reported eggshell thickness to be 0.33mm and Asuquo et al (1992) who reported 0.30mm. This is an indication of the possible improvement of these traits in commercial layers through breeding selection and other molecular biotechnological techniques over the years. The shell thickness and other indices of the egg monitored are especially useful in egg hatchability according to Yamak et al, (2015).

In terms of egg shape index, there were significant (P<0.05) differences as the ratio of egg width and egg length was compared competitively. The egg shape index value was highest in Isa Brown and the other three strains are however similar. The slight variation in the egg shape index could be due to stress according to Hughes and Black (1976) who reported that using Shaver 288 pullet which lays white eggs observed that hen distributed during a particular stage of egg formation may lay on an egg of characteristically abnormally shape.

Mortality was significantly influenced during this period as Bovans Nera recorded i.45% mortality and none were recorded by other strains.

Egg And Serum Biochemical Indices

The mean egg indices as represented in the table show that Albumen fat (mg/100g) was highest (P<0.05) in Isa Black while Dominant Black was least (P<0.05) behind Bovans Goldline and Bovans Nera which has the value (2.84 and 2.81 respectively) However Congjiao et al, (2019) reported no significant between strains for albumen protein, solid, pH or yolk solid in egg with significantly different weights. This contradicts the research work which highlights significant differences (P<0.05) between the strains. Concerning the yolk fat, the trend observed was Dominant Black (3.84) > Bovans Nera (3.70) > Bovans Goldline (3.25) > Isa Brown (3.10). Akbar et al, (1983); Hill et al,. (1990) and Khatun et al, (2016) reported that selected eggs of commercial strain weighed more and contained a higher percentage of albumen, albumen solids and albumen protein. However, this variation among strains has often been related to variations in egg size.

Table 3: Mean Egg and Serum Biochemical Indices of different Strains of Birds

a,b,c Mean along the same row followed by different superscripts are significantly (P<0.05), SEM.

The cholesterol (mg/100g) was highest in Bovans Nera (14.22) followed by Bovans Goldline (13.41), while Isa Brown (12.01) was least (P<0.05) behind Dominant Black (12.82). The cholesterol content of eggs has become a very important quality index among consumers. Cholesterol has an important role in the development of an egg embryo; it is a structural component of the cell membrane and is a precursor for hormones, vitamin D, and bile acids (Anton, 2007). Villa (2008) found that cholesterol content was positively correlated with egg and yolk weight, and negatively correlated with egg production and dietary protein level, However, these correlations were not significantly highest (P<0.05). The egg has come under increasing medical and dietary criticism due to its high level of cholesterol the high ratio of saturated to unsaturated fatty acids contained within egg yolk (Liscum, 2002) and the proportion of egg component as influenced by genetic background and age (Marion et al., Kline et al.,1965 and Stadelman and Pratt, 1989).

Fatty acids (mg/100g) were highest (P<0.05) significantly in Dominant Black (1.47) and Bovans Goldline (1.46) followed by Isa Brown (1.42) and least value (1.39) was observed in Bovans Nera. The concentration of fatty acid is influenced by the genetic rate of egg production and the composition of hen diets (Naber, 1993; Leeson and Caston, 2003). Furthermore, it also depends on breed and age of layer, management and nutrition and partly on synthesis in the liver during the synthesis of Lipo-protein. Egg calcium (mg/100g) was observed in Bovans Nera (61.51), Isa Brown (58.74) was next while the least (P<0.05) was recorded in Bovans Goldline (56.95) behind Dominant Black (57.94) which implies that Bovans Nera has better capacity to retain more calcium in its egg. The thickness of the egg is influenced by the mineral intake of the laying birds. More calcium seems to be needed for egg thickness than egg production; an egg with a shell less than 0.33mm thick is considered a poor marketing risk (Gunlu et al, 2003). Likewise Bovans Nera (83.67) and Dominant Black (70.47) had the highest and lowest (P<0.05) values of phosphorus (mg/100). In some experiments intake of nonphytate phosphorus below 200 mg/day throughout the laying period gave a good shell quality at the large amount (Owing et al,, 1977; Milaelian and Sell, 1981) but a value around 150 mg/day decreased egg production in an experiment of Rodrique et al,,(1984).

Serum indices as shown in the table indicate that Bovans Goldline (47.61) had the highest (P<0.05) and Isa Brown (42.67) had the lowest serum calcium. However, the literature on the haematological serum biochemical value of birds is limited to higher calcium levels than in non-productive females (Ritchie et al,, 1994). This agrees with Kunjarathiti Yapung et al (1987) who compared the levels of serum calcium between laying hen (18.10 + 2.64 mgdl) and broiler (6.25 – 13.75 mg/dl).

In the case of serum phosphorus Dominant Black had the highest 57.25 mg/100g and the least was recorded by Bovans Nera at 54.71 mg/100g, from the above table there is more serum phosphorus than the serum calcium and this is by (Edward and Saso, 1981) which stated that due to the specific needs for bone formation the requirement for phosphorus is laying hen is lower by at limestone order of magnitude than for calcium. Bovans Goldline had the highest combination of serum calcium and phosphorus and the least by Isa Brown. Also, Borman et al (1985) reported that low phosphate intake may also have a beneficial effect on shell quality since increased serum phosphate causes a decline in egg-specific gravity.

The serum cholesterol among all the strains was similar (P>0.05) and ranged between 12.04 – 12.25, with Bovans Nera recording the least and highest being recorded by Bovans Goldline, the proportion of egg components are influenced by the genetic background and age (Marion et al,, 1966; Kline et al,,1965 and Stadlman and Pratt, 1989). This agrees with the research finding as there were no significant differences between the strains due to their similar genetic background and similar age.

Serum protein was highest (P<0.05) in Bovans Nera (1.82) while Isa Brown and Bovans Goldline had similar values (1.73) and the least was Dominant Black (1.62).

SUMMARY, CONCLUSION AND RECOMMENDATION

A breakdown of the findings from the research showing the advantage of each strain are as follows, Bovans Nera had the best live weight at 18 weeks, Bovans Nera and Bovans Goldline recorded the best FCE at 18 weeks, these may be an advantage to producers of point of lay, Mortality to point of lay was lowest in Dominant Black, Egg production to 30 weeks of age was best in Isa Brown and Dominant Black, Shell thickness and Egg shape index which is very important in egg sales and transportation is also best in Isa Brown, Cholesterol was lowest in Isa Brown.

The study revealed differences in performance production characteristics and egg and serum biochemical indices, hence the best strain regards to the indices is Isa Brown, then Bovans Nera, Dominant Black and Bovans Goldline respectively.

In conclusion, the work is a means of evaluating new stock coming into the market by testing the performance of new strains and reappraising old ones in the reality of changing conditions. Further studies should be carried out to investigate egg-laying production pattern up till the entire life cycle of the bird to see if significant differences exist among the strains.

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