Effect of breed and non-genetic factors on growth traits of Fogera and their crosses with Holstein Friesian cows

Tazeb Gessess^1,2, Yohannes Dagnew², Solomon Abegaz³, Assemu Tesfa⁴ and Godadaw Misganaw²

¹ Animal Production and Forage Development expert, Chagni Cattle Breeding and Improvement Ranch, Metekel, Ethiopia
godadaw@gmail.com
² Department of Animal Sciences, College of Veterinary Medicine and Animal Sciences, University of Gondar, Gondar, Ethiopia
³ Department of Animal Production and technology, College of Agriculture, Woldiya University, Mersa, Ethiopia
⁴ Animal Genetic and Breeding expert, Andassa Livestock Research Center, Bahir Dar, Ethiopia

Abstract

The study was conducted to evaluate breed effect and some non-genetic factors on growth traits of Fogera and their crosses with Holstein Friesian cattle. A retrospective study for pre-weaning traits from 2011 – 2017 records at Chagni ranch and Andassa Livestock Research Centre were used. A total of 3239 calves for birth weight, 3090 calves for weaning weight and 107 for post-weaning weights were recorded from two-station herd books. Growth traits were analysed using general linear models. The fixed effects were breed, birth year, season, sex, parity and location. The overall mean of birth and weaning weights were 22.3±0.12 and 93.3±0.85 kg for Fogera and 24.6±0.11 and 112±0.84 kg for the crossbred calves, respectively. All fixed factors had effect on birth weight, weaning weight and pre weaning average daily gain of calves (p<0.01). The overall post weaning weight for Fogera and their crossbred calves were 101±1.62 and 111 ±2.65 kg respectively. The post weaning average daily gain for Fogera and crossbred calves was 308 ± 14.7and 289 ± 24.0 g, respectively. Except dam parity, all the other factors were significant (p<0.05) and caused variation in post-weaning weight. Since most of factors here studied showed a significant effect on growth traits, emphasis should be given on the non-genetic factors for improving weight gain.

Keywords: breed conservation, crossbreeding, daily weight gain, heritability, ranch

Introduction

Ethiopia is endowed with huge livestock resources of varied and diversified genetic pools with specific adaptations to a wide range of agro-ecologies (Roessler et al 2008; Duguma et al 2010). Ethiopia is gifted 32 cattle breeds, which have diversified phenotype, production and adaptation performances (Kebede et al 2017). The Fogera cattle are among the 32 recognized indigenous cattle breeds in the country and it is known by a better adaptation of swampy and wetland areas found around Lake Tana (Bitew et al 2010). These cattle are as intermediate Zebu- Sanga type, the so-called Zanga and selected for genetic improvement as a dual-purpose animal (Melaku et al 2011a).As a result, this breed is maintained in two stations (Chagni ranch and Andassa Livestock Research Centre) for the purpose of conservation and improvement for a better production potential.

Currently, pure and crossbreeding of Fogera cattle breed is underway at Chagni Ranch and Andassa Livestock Research Center for improving milk production and the growth performance of the calves. Growth of an animal is influenced by genetic and non-genetic factors; these include genotype, sex, age, nutrition and environment (Bourdon 2000; Uğurlu et al 2016). The pre-weaning growth performance of a calf is one of the most important factors for beef productivity (Mpofu et al 2017). Reduced growth performance is the major limiting factor amongst other factors of cattle production in the tropics (Jones and Hennessy 2000). An animal of good genetic makeup may perform poorly when the production environment is not favorable due to the negative interaction between the animal’s genes and its environment (Boitsime 2006). Well-grown dairy calves and heifers play an important role in the future success of all dairy farms, and the phase of growth occurring between birth and weaning may have major economic importance. Previous research has demonstrated that greater pre-weaning average daily gain (ADG) can have a positive effect on the future production (Soberon 2013) mainly due to higher growth rate during early life.

As a result, many studies have been done to improve the growth performance of livestock species through pure breeding (selection) and/or cross breeding with advanced breeds. The positive effects of crossbreeding on growth performance of calves and milk production have been reported by Assemu (2015). Body weight of calves is strongly influenced by breed, sex, birth type, age of dam, and season of calving (Sendeku 2015). Although there are some outdated researchers on the pre-weaning growth rates of pure Fogera cattle (Gebeyehu et al 2005; Amuamuta et al 2006; Melaku et al 2011); studies regarding the effect of non-genetic factors on post-weaning growth of pure Fogera breed calves, pre and post weaning growth for their Holstein Friesian crosses is scanty. Therefore, this study was aimed to evaluate the effect of breed and non-genetic factors on the growth traits of Fogera and crosses with Holstein Friesian managed under on station condition.

Materials and Methods

Study area description

The study was conducted at both Chagni ranch and Andasa Livestock Research Center (Figure1). Chagni cattle breeding and improvement ranches found in Guangua district of Awi Zone, Ethiopia and situated about 505 km North-west from Addis Ababa. The area has an altitude of 1829 meter above sea level. The ranch receives an average annual rainfall of 1730 mm and the average temperature ranges from 13.7 to 29.5 ^oC. The rainfall distribution is bi-modal (Assemu et al 2016). Similarly, Andassa Livestock Research Center (ALRC) is found at 587 km Northwest of Addis Ababa, and 22 km South of Bahir Dar city. The Center is found with an elevation of 1730 meter above sea level. It receives an average annual rainfall of 1150 mm with temperature ranging from 6.5^oC to 30^oC (Addisu et al 2010).

Figure 1. Location of study ranches

Description of cattle population

The current population of cattle reared at the two sites are 1884 heads (Andassa and Chagni ranch, 2021). The proportion of Fogera cattle breed is much higher than the Holstein Frisian crossbred cattle (1510 vs. 374 heads). Because, according to the Centers information most of crossbred calves are distributed to fatteners and local farmers after a yearling age. Chagni ranch (1341 heads) has more number of cattle than Andassa livestock research centre (543 heads). The average weaning age of calves at the two Centers is 8 months.

Study design and data sources

The study stations were selected based on the existence of Fogera cattle and its improvement activity with complete records on the targeted growth traits. Calves information of Fogera breed and their 50% crosses with Holstein Friesian cattle was analysed. Eight months were considered as the weaning age of calves at the two stations. Therefore, a calf was defined as young cattle less or equal to 8 months for pre-weaning growth determination and, 8 to 12 months of age for determining the post-weaning growth. Records from 2011-2017 were considered and used to evaluate for pre- and post-weaning growth performances of both crossbreds and Fogera cattle breed. A total of 3239 calves for birth weight and 3090 for weaning weight were recorded from the two-location herd book retrospectively. Parity was classified as 1, 2, 3, 4 and ≥5. Because of small number of observations in parity five and above, it was considered as ≥5. A retrospective study was carried out based upon the secondary data obtained from the two study location sources. Factors such as sex, parity, breed, year, location and season viz. growth traits (birth weight and weaning weight) recorded at the two centres was screened and stored in the data bank of this study. Besides, measurement was taken from 107 live calves form 8-12 months of age (post weaning) from all available crossbred and Fogera calves using ground weighing scale. In both ranches natural mating and artificial insemination service was practiced.

Data management and analysis

Data that was measured and recorded for pre- and post- weaning growth rates, and arranged, on Microsoft Excel spread sheet and coded. Finally, recorded data re-arrangement was done from excel into the SAS window 9 for further analysis.General linear model (GLM) procedures of the SAS released 9.1 (2009) was employed to determine the fixed effects of year of birth, season of birth, breed type, parity, location and sex on the growth performances of calves. Least squares mean from General linear model (GLM) procedures of SAS was employed to compare the means. The following model was used for determine the effect fixed factors on the growth traits of Fogera and its crossbred calves.

Model 1: Y_ijklmno= μ + G_i+S_j+Pk+B_l +Y _m+ L_n+ (G x L)_in + e_ijklmno

Where, Y_ijklmno= birth weight, weaning weight, and pre weaning ADG

μ = population mean

G_i= fixed effect of the i^th genotype (i= Fogera, crossbred)

S_j= fixed effect of the j^th sex (j= male, female)

P_k= fixed effect of the k^th parity (k = 1, 2, 3, 4 and ≥5)

B_l= fixed effect of the l^th birth season (l= wet, dry)

Y_m= fixed effect of the m^th year of birth (m = 2011-2017)

L_n= fixed effect of the n^th location (n= Chagni, Andassa)

(G x L)_in = breed by location interaction effect

e_ijklmno= random error

Model 2: Y_pqrstuvx= μ + S_q +G_r+ P_s + L_t+ Y_u + W_v + (G x L)_pt + e_pqrstuvx

Where, Y_pqrstuvx = the observation on post-weaning weight and post weaning ADG

μ = overall mean

S_q = effect of q^th sex (q= male, female)

G_r= effect of r^th breed (r=pure Fogera, crossbred)

P_s= effect of s^th parity (s=1, 2, 3, 4 and ≥5)

L_t = effect of t^th location (t= Chagni, Andassa)

Y_u= fixed effect of the u^th year of birth (u = 2011-2017)

W_v= fixed effect of the v^th birth season (v= wet, dry)

(G x L)_pt = breed by location interaction effect

e_qrstuvx = random error

Results

Least squares means for the effects of breed group and non-genetic factors like season of calving, parity of dams, sex of calves, year of birth and location on birth and weaning weight of Fogera and their crosses with Holstein Friesian cattle are presented in Table 1. The overall average birth weight and weaning weight of calves born in the two locations was 23.5 ± 0.10 kg and 102 ± 0.76 kg respectively (Table 1).

The overall average pre and post weaning daily weight gain was 245 ± 4.07 g and 299 ± 14.7 g respectively (Table 2). Unlike the pre weaning average daily weight gain, post weaning average daily weight gain was not significantly different across all fixed factors considered in this study ( p>0.05).

Breed group effect

Perusal results showed that, breed had an effect on the growth traits of Fogera and their crosses with Holstein Friesian cattle (p <0.01). Crossbred calves were on average 2.30 kg and 17.7 kg heavier than from pure Fogera calves at birth and weaning age respectively (Table 1). As pointed out in Table 2, pre weaning average daily weight gain for Fogera calves (225 ± 4.84 g) were lower than with that of crossbred calves (264 ± 4.38 g)(p<0.01). This implies that, crossbred calves obtain on average 39 g higher daily weight than the pure Fogera calves during pre-weaning stage. Similarly, the post weaning weight of crossbred calves were significantly higher than Fogera calves. The study also showed that weaning weight of calves were reported to have a correlation with birth weight which means that calves born with greater weight at birth had a higher post weaning weight.

Sex of calf

Sex had also an influence on most of the growth traits of Fogera and their Holstein Frisian crossbred calves. This may be attributable to different physiological functions in both sexes, mainly of hormonal nature. As presented in Table 1, male calves weighed heavier than female calves at birth and weaning age (p< 0.05). In the pre-weaning age, male calves on average earned 9 g more weight than female calves on a daily basis (p<0.01). However, post-weaning average daily weight gain was not significantly affected by sex (Table 2).

Dam Parity

The effect of parity on birth weight showed variation (P< 0.01) as calves born in first and later parities had lighter in weight than calves born in other parities (Table 1). Calves which born from the fifth parity dams and above had lower pre-waning average daily weight gain than the first four parities. This might be associated with the decreasing milk production potential of dams from parity five onward. There was no significant difference between parities in post weaning weight of calves (Table 2).

Birth season and year

Calves born in the wet season had higher birth weight than those calves born in dry season (p< 0.05) (Table 1). This may be reflected from the availability of abundant high quality green pasture in the wet season. In contrary to birth weight, calves born in the wet season had 28 g lower average daily weight gain than born in the dry season during pre-weaning age (Table 2). There was also variation in birth weight among the seven years considered in the present study (p< 0.05). Higher birth weight (24.3 ± 0.15kg) was recorded in 2015 where as the least (22.4 ± 0.20kg) was in the year 2011 (Table 1). To the opposite of birth weight, higher weaning weight (113 ± 1.34 kg) and pre-weaning average daily weight gain (278 ± 7.87 g) were recorded in 2011 year (Table 1 and 2).

Location

Location showed a difference on the birth weight of Fogera and their Holstein Frisian crossbred calves (p<0.01). Calves born in Andassa Research Center (25.1 ± 0.18kg) was heavier than with that of born in Chagni ranch (21.9 ± 0.06 kg).Unlike birth weight, calves reared at Chagni ranch (320 ± 2.41 grams) had much higher average pre-weaning daily weight gain than those reared at Andassa livestock research center (169 ± 7.26 g) (Table 2). At the same time, calves which were raised at Andassa Research Centre had higher post weaning weight than those calves in Chagni ranch (Table 2) (p< 0.05)

Interaction breed * Location

Breed by location interaction had no effect on birth weight of calves reared at Chagni ranch and Andassa Research Centre in both breeds (Table 1) (p>0.05). However, a significant interaction effect of breed by location was noted on weaning weight, pure Fogera and their Hostein Friesian crossbred calves exhibited the highest weight at Chagni ranch than Andasa Research Centre. On the other hand, the interaction effect of breed and location on post weaning weight was significant in which pure Fogera and their Holstein Friesian crossbred calves were heavier at Andasa than at Chagni. The result of breed by location interaction indicated that pure Fogera calves and Hostein Friesian crossbred calves were superior in pre-weaning ADG at Chagni ranch than Andasa Research Centre (p <0.01). On the contrary, the Hostein Friesian crossbred calves were significantly superior in post-weaning ADG at Andasa than Chagni improvement centre (p<0.05).

Discussion

The average birth weight estimated for pure Fogera calves (22.3 ± 0.12 kg) in the present study was relatively higher than from previous reports on the same breed (Assemu et al 2016; Aynalem 2006; Sendeku 2015). The deviation of birth weight of the present study might be due to differences of management and feeding practices during dam pregnancy period and the result of genetic gain in the last decade. In line to the current study, Addisu and Hegde (2003) reported a significance effect of breed on birth weight of Boran and its crossbred with Holstein Frisian cows. The birth weight of Fogera-Holstein Friesian crossbred calves was nearly comparable to earlier reports of pure Fogera (24.9 ± 0.37 kg) Amsalu (2003) and Barka (24.5 ± 2.9 kg) Zewudu et al (2004). On the other hand, many previous studies reported higher birth weight estimates which range from 26.2 to 27.7 kg for crossbred calves (Amsalu 2003; Demeke et al 2003b; Hailu and Tadele 2003; Ababu et al 2006). However, the estimate of the current study was better than from a report of Habtamu et al (2010a) for Horro-Friesian crosses (22.1 ± 0.14 kg) and Obese et al (2013) for Sanga-Friesian cross (21.8 ± 0.5 kg).

The estimated weaning weight of Fogera calves in the current study (93.2 ± 0.85 kg) was less than from the report of Addisu (1999) for the same breed (114 kg), Makonnen et al (2012) for Horro breed calves (157 kg) and Bayou et al (2015) for Sheko breed calves (122.8 kg). On the other hand, a similar finding of weaning weight was also reported by Zewudu et al (2004) for Mahibere-Silassie composite calves and Sendeku (2015) for Fogera calves. There was also a lower estimation of weaning weight in many previous studies like Getinet et al (2009) reported 91.7 kg for Ogaden breed; Abera et al (2012) reported 88 kg for Horro breed; Tegegne et al (2013) reported 79 kg for the Boran breed and Assemu et al (2016) reported 88.6 kg for the Fogera breed.

The overall pre weaning average daily weight gain (224 ± 4.84 g) reported for Fogera calves in this study was lower than from the finding of previously reported for the same breed (Addisu 1999; Giday 2001; Almaz et al 2018). This may be reflected from the difference of season, year and management practices in the last two decades. The current study confirmed that post weaning average daily weight gain was not significantly different across breed and non-genetic factors which is in agreement with the reports of many previous studies (Bourdon 2000; Addisu and Hegde 2003; Aynalem2006; Getinet et al 2009). However, Bayou et al (2015) found significant effect of non-genetic factors on the post-weaning daily weight gain of Sheko breed calves. The overall post weaning average daily weight gain of Fogera-Holisten Friesian crossbred calves was 308g/day which is higher than from the performance of Horro-Holestien Frisian crossbred calves (263g/day) reported by Habtamu et al (2010b). The post weaning average daily weight gain of pure Fogera calves reported in the current study (289g/day) was higher than from the report of Aynalem (2006) on the same breed (272 g/day) and Zewudu et al (2004) for Sheko breed (129g/day). On the other hand, a higher daily weight gain of calves was also reported by Bourdon (2000) for Fogera calves (297g/day) and, Jones and Hennessy (2000) for Nguni breed of South Africa (438g/day).

In consistence to the current study, many authors (Zewudu et al 2004; Obese et al 2013; Zeleke and Getachew 2017) reported that the weight of crossbred calves at post-weaning age was significantly higher than from the pure breed calves. However, the post weaning weight of crossbred calves estimated in this study (111 ± 2.65 kg) was lower than from a previous report which falls under the range 124 -140 kg for local-Holstein Friesian crossbreds in Ethiopia (Amsalu 2003; Hailu and Tadele 2003; Ababu et al 2006). The post-weaning weight estimated for Fogera calves in the present study (101 ± 1.62 kg) was higher in comparison with Ogaden and Boran breed calves (Yohannes et al 2001; Getinet et al 2009).

In the present study, sex of calves had a significant effect on birth and weaning weight that is consistent with the reports of Assemu et al (2016) and Sendeku (2015) for Fogera calves; and in contrast with the report of Almaz et al (2018). In support of the current study, many researches were confirmed that male calves were heavier than female calves (Hailu and Tadele 2003; Wasike 2006; Habtamu et al 2010a; Assemu et al 2016). However, many other reports indicated that calf sex had no significant effect on post- weaning weight (Addisu 2003; Ayinalem 2006; Jiregna et al 2006; Habtamu et al 2010a; Obese et al 2013) which is similar to the case of post weaning average daily weight gain of this study.

In contrary to the current study, Getinet et al (2009) showed that season of calving had no significant effect on birth weight of Fogera and their crossbreds. This difference might be reflected from the variations of good herd management and forage availability in the season where the study was conducted. The same to the present study findings, a significant effect of year on birth and weaning weight was indicated by many authors (Getinet et al 2009; Habtamu et al 2010a; Almaz et al 2018; Manzi et al 2012; Sendeku 2015; Assemu et al 2016). Variability in management practice, forage quantity and quality and other environmental difference may contribute to the significant differences of year on birth weight.

The current study justified that, calves born in first and later parities had lighter birth weight than with those born in other parities, which is in line with the report of Habtamu et al (2010a) for Horro and Holstein Friesian calves and Assemu et al (2016) for the Fogera and Holstein Friesian calves. This implied that this trait attains its maximum at the third parity as indicated by Bayou et al (2015). It is mainly associated with the maturity of the cows to have well developed cavities for fetus growth and development, whereas agedness may affect in the latter parities. The same to the present study, lighter weaning weight at the first and last parities than the intermediate parities were reported by Bourdon (2000), Habtamu et al (2010a) and Assemu et al (2016). However, contrary to the study of Sendeku (2015), parity of dam had no significant effect on weaning weight of Fogera calves. Getinet et al (2009) and Almaz et al (2018) reported that, calves which born from the fifth parity dams and above had lower daily weight gain than the first four parities which is similar to the report of this study. This might be linked with the reduction of milk yield and mothering abilities in older parities, which in turn affects the birth weight and subsequent growth of the calf. The not-significant effect of dam parities on post-weaning weight of this study was supported by Bayou et al (2015), but contradicts with the reports of Giday (2001) and Getinet et al (2009).

The finding of current study shows except birth weight all growth traits were significantly affected by the interaction effect of breed by location. The significant effect of interaction of breed by location on post weaning weight was supported by Assenza et al (2010) which indicated the existence of significant genotype by environment interaction for yearling weight and growth during the post weaning period in Creole cattle, fattened in two contrasted environments. Similarly, in line with the huge effect of the interaction on weaning weight and pre-weaning average daily weight gain of Fogera-Holstein Frisian crossbred calves, Rashid et al (2016) reported a large effects of genotype by environment on growth traits for F1 Brahman-Local crossbred cattle between two management systems in tropical conditions.

Conclusion

• Breed showed huge variation on the growth performance of calves.
  
  
• Conservation of the adaptive characteristics of the Fogera cattle should be maintained and selective breeding could be recommended for smallholder communities through designing and implementing appropriate genetic improvement schemes.
  
  
• Most of the non-genetic factors were important source of variation for the growth performances of Fogera and their crosses with Holstein Friesian cattle.
  
  
• Thus, further efforts are needed to improve the production environment for improving such traits so that the declining performance of the animals across the non-genetic effects should be improved.

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