Evaluation of production performance of Arsi-Holstein Friesian crossbred dairy cattle: A case of Assela Model Agricultural Enterprise, Arsi zone, Oromia Region

Teshome Gedefa, Ajebu Nurfeta and Nega Tola

Salale University, Salale, Ethiopia
teshu.bi@gmail.com

Abstract

The objective of this study was to evaluate the productive performance of Arsi-Holstein-Friesian crossbred dairy cows at Assela Model Agricultural Enterprise (AMAE). A retrospective study was carried out using data recorded from 1996 to 2011 to estimate adjusted lactation milk yield (ALMY, adjusted 305 days), lactation length (LL), birth weight (BW) and weaning weight (WWT). Fixed factors considered were year (16), season (3), parity (6) and blood level (4). The overall least square means of ALMY, BW, WWT, LL, were 2155 kg, 34 kg, 71 kg, and 314 days, respectively. Season had no significant effect on ALMY and LL. Year of calving had significant (p<0.05) effect on ALMY. Year of calving showed significant influences (p<0.01) on LL. There was no significant difference among blood levels in ALMY and LL. Lower (p<0.05) ALMY was recorded for parity 6 ^th+ than that of 2^nd and 3^rd, while the other parities were intermediate. There was no significant (p<0.05) difference among parities in LL. Sex and blood levels showed significant (p<0.05) effect on BW and WWT. The BW for males was higher (p<0.05) than that of females, whereas, the WWT for female was higher (p<0.05) than that of male. Year had an important role in determining the performance of dairy cows indicating there was variation in feed availability and quality as well as variation in management through the years. Therefore, stabilized environment, setting breeding program, and benchmarking parity number is important to improve productive performance of the farm.

Key words: Arsi, crossbred, holstein-friesian productive

Introduction

There are a huge number of cattle in Ethiopia, with 53.4 million heads of genetically diverse cattle (CSA 2011) and has the largest population in Africa. Cattle production plays an important role in the economies and livelihoods of farmers and pastoralists. The agricultural sector in Ethiopia, engaging 85% of the population, contributes 52% to the gross domestic product (GDP) and 90% to the foreign exchange earnings (CSA 2008). The share of livestock is estimated at 45% of the gross domestic product. Cattle produce a total of 3.6 billion liters of milk (CSA 2011). Despite the large numbers, the production and productivity per animal is very low (Aynalem 2006). This is because indigenous cattle have been naturally selected for years towards adaptive traits as tolerance and resistance to diseases, high fertility, unique product qualities, longevity and adaptation to harsh environments and poor quality feeds. Attempts, to improve the productivity of cattle, have been made especially in the area of crossbreeding for the last five decades but with little success (Aynalem 2006).

Ethiopia has a huge potential to be one of the key countries in dairy production for various reasons (Pratt et al 2008). These include a large population of milking cows in the country estimated to be 10.7 million (CSA 2011), a huge potential for production of high quality feeds under rain fed and irrigated conditions, existence of a relatively large human population with a long tradition of consumption of milk and milk products and hence a potentially large domestic market (Holloway et al 2000), existence of a large and relatively cheap labor force and opportunities for export to neighboring countries and beyond.

The total consumption of milk in the developing countries is projected to increase from 64 million metric tons in 1993 to 391 million metric tons by the year 2020, which is 138 percent increase. Much of this increased demand will be in urban centers in which population is to grow at a rate of 5-6 from 1990-2025 (Mihret 2006). Moreover, the trends of population increase; income growth and urbanization will fuel this tremendous growth in demand.

Milk yield is a product of animal genetic and environmental interactions (Johnson 1991). Milk yield for specific genotype is the function of climate and its interactive influences on the quantity and quality of feeds, the presence of disease and parasite and the utilization of technology to alleviate nutritional, thermal and health limitations. Milk production systems in the tropics are diverse. At one extreme the systems are similar to those in most industrialized countries and are based on cows of high genetic potential given “high quality feeds” which includes fodder crops/silage, grain and protein concentrates (Leng 1991). Milk production per cow is extremely high and technological inputs are high. Even in some specialized large scale farms lactation milk yield of pure Holstein cows is far below their expected genetic potential (Sendros and Tesfaye 1998).

Motivation for popularizing crossbreeding between high-yielding European dairy breeds and cattle breeds adapted to local environments was initiated in the national agricultural research system (NARS) of Ethiopia in the early 1970s. As compared to other dairy cattle genetic improvement strategies, this approach was believed to be the only feasible and quick way of increasing milk production in Ethiopia. The outcomes of the crossbreeding programs have been amply reported in several literatures with various outcomes (Demeke et al 2004).

However, the dairy cattle genetic improvement program started in Ethiopia in the early 1970s has never been subjected to periodic evaluation for the genetic and environmental trends. Thus, the effectiveness of this program is not clearly known. Moreover, no information is available on the status of the national dairy cattle genetic improvement program that guide policy makers, development planners and breeders to redesign appropriate breeding programs that respond to the current scenarios in Ethiopia. The purpose of this study was, therefore, to investigate production performance of Arsi-Holstein-Friesian crossbred of different blood levels at Assela Model Agriculture Enterprise Dairy Farm. Therefore, the purpose of this paper was evaluating the productive performance of dairy cows with different exotic blood level.

Materials and methods

Description of the study areas

The data was conducted at Assela Model Agriculture Enterprise Dairy Farm, which is located in the Arsi Zone of the Oromia Regional state about 175 kilometers from Addis Ababa. The city has a latitude and longitude of 7°57′N39°7′E and 7.95°N39.117°E, with an elevation of 2430 meters above sea level, respectively and with the minimum and maximum temperature ranging from 5 and 18 °C, respectively, around the year (KARC 2008)

Data collection method and study design

A retrospective type of study was carried out to evaluate the productive performance of Arsi-Holstein-Friesian crossbred Dairy Farm. Recorded data for the last 16 years (1996-2011 G.C.) on the productive of the breed in the Farm was used for this study. Only data’s with complete information was included in the study.

Data analysis

The General Linear Models (GLM) procedure of Statistical Package for Social Sciences (SPSS 2007, (version 16.0) was used for data analysis. Mean of different traits were then tested by Duncan Multiple Range. Two statistical models were used during data analysis; model 1 was used to analysis data on LMY and LL, model 2 for BW and WWT.

Model 1: Yijklot = u + Bi + Sj + YRk + Pl + eijkl

Where:

Yijklot = LMY and LL of n^th cow in l^th parity, k^th period of calving, j^th season of calving and i ^th exotic blood level

u = overall mean

Bi = the effect of i^th exotic blood level (i=1…, 4)

Sj = the effect of j^th season of calving (j=1…, 3)

YRk = the effect of k^th period (year) of calving (k=1…, 16)

Pl = the effect of l^th parity (l=1…, 6)

eijkl = random residual error term

Model 2: Yijk=μ+ai+bj+ (a*b) k + eijk

Where: Yijk = birth weight (BW) and weaning weight (WWT) of n^th cow in i^th sex, j^th blood levels and k^th interaction

u = overall mean

ai = the effect of i^th sex (i=1, 2)

bj = the effect of j^th blood levels (j=1…, 4)

(a* b)k = k^th effect of sex and blood level interaction

eijk = random residual error term

Results and discussion

Adjusted lactation milk yield

Least square means of lactation milk yield and days in milk are summarized in Table 1. The overall least square means of adjusted lactation milk yield and days in milk observed in this study were 2155 (kg) and 314 (days), respectively. Analysis of variance showed that year of calving had significant (p < 0.05) effect on lactation milk yield. In addition, year of calving showed significant effect (p < 0.05) on days in milk. Season of calving showed non-significant effect on lactation milk yield and days in milk.

Lactation milk yield for the year 2008 was lower than that of the years 1996, 1997, 2005 and 2010. In addition, lactation milk yield for 1996 was significantly (p < 0.05) higher than that of the other years. Moreover, lactation milk yield for the year 1997 was significantly higher (p < 0.05) than that of the years 2002, 2004 and 2007. Lactation lengths for the year 2005 was lower than that of the years 1996, 2000, 2010 and 2011, whereas, the lactation length for the other years were intermediate.

Adjusted lactation milk yield in the current study was lower than the values reported by Gebeyehu (2005), who reported that lifetime milk yield of F1, 3/4, 7/8 and 15/16 Friesian x Boran crosses to be 14342, 12074, 7891 and 7343 kg, respectively. On the other hand, 2042.11 kg, 1900.3 kg and 1872 kg were reported by Belay et al (2012), Kefena et al (2011) and Kiwuwa et al (1983) for Zebu-Holstein-Friesian crossbred dairy cows in Jimma Town, in the central tropical highlands of Ethiopia and Assela, respectively, which was lower than the current result.

Million and Tadelle (2003) and Gebeyehu (1999) reported absence of season effect on lactation milk yield, which agree with the present result. However, Amasaib et al (2011) reported that animals which gave birth in winter produced more total lactation milk yield than that of animals which gave birth in summer and autumn, whilst they reported no difference in daily milk yield among seasons. In the present study, the lack of effect of season on milk yield could be explained by supplementation, which probably evened out feed supplies across seasons eliminating possible feed related seasonal fluctuations in milk yield (Muasya et al 2007). In addition, it is indicated that in the tropics, the influence of climatic conditions may be negligible under optimal feeding and management conditions (Aynalem et al 2008). Moreover, Hirooka and Bhuttyan (1995) reported that season of calving had not influenced many milk production traits of crosses of local and Holstein cows.

The significant effect of year on lactation milk yield was reported for Zebu and their crosses with Holstein Friesian cattle (Gebeyehu 1999; Million and Tadelle 2003 and Kefena et al 2011) and Sahiwal cattle (Trail and Gregory 1981). The variation in milk production performance over years may not only be caused by inter-annual random change of the climatic factors but also include management changes (Aynalem et al 2008).

Kiwuwa et al (1983) reported lower total lactation milk yield for Zebu, local Arsi, ½ Jersey ½ Arsi, ½ HF ½ Arsi and ½ Exotic ½ Arsi than the current results, whereas, ½ HF ½ Zebu is comparable with this study. Moreover, lactation milk yield for 75% exotic blood levels of the current study was comparable with 75% HF-Arsi, HF-Zebu, Exotic-Arsi and HF-Local crosses (Kiwuwa et al 1983). Abdinasir (2000) reported 1547 kg per lactation for 25-62.5% exotic blood levels of Arsi-Holstein Friesian, which is lower than the present result. On the other hand, Abdinasir (2000) reported higher lactation milk yield for >75% Arsi-HF crossbred, which is higher than the current study with the same blood levels and breeds. The tendency of increasing lactation milk yield with no significant difference as exotic blood levels increased was consistent with Kiwuwa et al (1983) and Bee et al (2006) in Ethiopia and Sudan, respectively. However, according to Msanga et al (2000) and Amasaib et al (2011) 62.5% exotic blood level was superior in total lactation milk yield than any crossbred.

According to Preston and Murgueitio (1992) if total performance is taken into account (fertility, survival, growth rate and milk yield), animals of an intermediate level of European exotic blood levels are likely to be superior. This is further supported by Syrstad (1996) who reported that optimum point of upgrading lies between 50% and 75% Bos taurus breeds for milk production. As the level of exotic inheritance increased towards 100%, the problem of high mortality and reduced fertility increased (Bee et al 2006). The absence of differences in lactation milk yield among different blood levels might be due to deterioration of heterosis effect of back crossing. Cunningham (1991) indicated that the possible explanation for the low productivity of F2 is the idea that blocks of genes giving favorable epistatic effects in the parental breeds and the F1 may be broken up in the F2 and subsequent generations.

Million and Tadelle (2003), Million et al (2010), Kefena et al (2011) and Gebeyehu (1999), reported significant effect of parity on lactation and daily milk yield, which agrees with the current result. Peak lactation milk yield was reported at 6^th parity (Million et al 2010), 4^th - 5^th parity (Goshu and Mekonnen 1997) and 3 ^rd - 8^th parity (Kefena et al 2011) for different breeds in Ethiopia. A rapid declining trend in adjusted lactation milk yield was observed at 6^th+, which agrees with Mackinnon et al (1996) for crossbreds of Ayrshire, Brown Swiss and Sahiwal in Kenya and Sattar et al (2005) for HF cows in Pakistan. Moreover, Madani et al (2008) reported peak lactation milk yield at 2^nd - 3^rd, which agrees with this study. Cows in 6^th+ parity were no longer better producers' compared with those in their 2^nd and 3 ^rd parity. This may be partly explained by highest milk production capacity coupled with greater feed intake in intermediate cows than young ones and similarly due to more number of secretory cells at intermediate ages and due to inexperienced lactation stress in young animals (Bee et al 2006). The decline in milk production at 6^th+ parity may be due to turnover of secretory cells, with higher numbers dying compared to the newly produced active secretory cells (Epaphras et al (2004).

Lactation length

Results of adjusted lactation milk yield and days in milk by blood level and parity are presented in Table 2. Statistically there was no significant (P > 0.05) difference among blood levels in adjusted lactation milk yield and days in milk. A lower (p < 0.05) value in adjusted lactation milk yield was recorded for parity 6^th+ than that of second and third, while the other parities were intermediate. There was no significant (p > 0.05) difference among parities in lactation length.

The average lactation length in the current study was comparable with the study by Asaminew and Eyasu (2009) and Adebabay (2009), who reported 303 days. However, it was lower than the findings of Kefena et al (2011) (333 days), Zelalem (1999) (351 days) and Kiwuwa et al (1983) (350 days) for Zebu-Friesian crossbred in Ethiopia. On the other hand, days in milk of 279 days, 242 days, 292 days, and 247 days were reported by Million and Tadelle (2003), Belay et al (2012), Sattar et al (2004) and Sattar et al (2005) for Barca, Zebu-HF crossbred in Ethiopia, Jersey in Pakistan and HF in Pakistan, respectively, which is shorter than the present study. The variation might be due to variation in management of the animal, breeds, and the models were used.

According to Addisu et al (2010) animals which gave birth in dry season had longer lactation length than that of animals which gave birth in wet season, which is not consistent with the present result. On the other hand, Amasaib et al (2011) reported insignificant effects of season on lactation length, which agree with the current finding. The variations among year in lactation length were reported by Kefena et al (2011), Addisu et al (2010) and Kiwuwa et al (1983), which is consistent with the present result. The variation in milk production performance over years may not only be caused by inter-annual random change of the climatic factors but also due to management changes (Aynalem et al 2008).

The level of exotic blood level had no effect on lactation length, which agrees with Yahya et al (2011) who reported insignificance effects of exotic blood level on days in milk for cows with 50%, 62.5 and 87.5%. On the other hand, they reported significant effects of exotic blood level on days in milk for cows with 25%, 75% and 100% for Kenana- Friesian crossbred cattle in central Sudan. In another study, lactation length of 272 days was reported for local Arsi breeds (Kiwuwa et al., 1983), which is shorter than the four blood levels in the current study. In addition, Kiwuwa et al (1983) and MOA and FINNIDA (1996) reported longer lactation length for 50% exotic blood levels of Arsi-HF crossbred than the present study. Moreover, Abdinasir (2000) reported longer lactation length for 25-62.5% and >75% exotic blood levels of Arsi-HF crossbred than the present study.

The lack of effect of parity on days in milk is not consistent with the finding of Kefena et al (2011), Sattar et al (2005) and Amasaib et al. (2011). Different authors reported maximum days in milk at different points for different breeds. Kefena et al (2011) and Sattar et al (2005) reported longer lactation length at the first parity, whereas, Amasaib et al (2011) reported longer lactation length at the second parity. The differences reported in several studies may be due to the differences in environment, management and breeds.

Birth and weaning weight

Table 3 summarizes the effects of sex and blood levels on birth weight and weaning weight. The overall least square means values of birth and weaning weight were 34 and 72 kg, respectively. The birth weight for male was higher (p < 0.05) than that of females. The weaning weight for female was higher (p < 0.05) than that of male.

Animals with 50% exotic blood levels had lower birth weight than those animals with 62.5-68.75% exotic blood levels, while, animals with 75% and >75% exotic blood levels were intermediate. Animals with 62.5-68.75%, and >75% exotic blood levels had higher weaning weight than those animals 50% with blood levels, while, 75% exotic blood levels.

The overall mean birth weight of calves seen in this study was higher than birth weight of Boran and Boran-HF crossbred (28.2 kg) and Jersey (22.87 kg) by Aynalem et al (2011) and Habtamu et al (2010), respectively. Weaning weight of calves in the current study was higher than Boran-HF crossbred (55.36 kg) reported by Aynalem et al (2011), but lower than that of Jersey (108.88 kg) as reported by Habtamu et al (2010). Aynalem et al (2011) reported 26.0 kg birth weight for 50% Boran-HF, which is comparable with the current result. The same authors reported lower birth weight for 62.5, 75 and 87.5% Boran-HF crossbreds than the current result. Aynalem et al (2011) reported lower weaning weight for Boran, ½ Boran ½ HF, 3/8 Boran-5/8 HF), ¼ Boran ¾ HF and 1/8 Boran 7/8 HF than the current blood levels. The small weaning weight might be due to poor post management. According to Mukassa-Mugerwa et al (1991) feeding higher quantity of milk during preweaning resulted in better growth.

The difference in birth weight between sexes in this study was inconsistent with the finding of Addisu et al (2010) under partial suckling system at Andassa Livestock Research Centre. Habtamu et al (2010) reported that male calves were heavier than female calves at birth, which is agreed with this study. The variation among blood levels in birth weight might be because of the heterosis effect (Aynalem 2006). Moreover, in mammals, growth is influenced by the genes of the individual, environment provided by the dam and other environmental effects (Albuquerque and Meyer 2001).

Birth weight of 50% blood levels was comparable with the crossbred of ½ Holstein ½ Arsi, ½ Holstein ½ Zebu, and ½ Exotic ½ Arsi, while higher than ½Jersey ½Arsi crossbred (Kiwuwa et al 1983). In addition, Kiwuwa et al (1983) reported lower birth weight for ¾ Friesian ¼ Arsi, ¾ Friesian ¼ Zebu, ¾ Exotic ¼ Arsi and ¾ Friesian ¼ local crossbred than this study.

The variation between sexes on weaning weight was reported by Habtamu et al (2010). They reported that male calves are heavier than female calves at weaning time, which is not consistent with the present study. This might be attributed to different physiological processes in the two sexes. Their differences in growth increased with age implying that sex effects are more pronounced with age after puberty (Hailu et al 2008). Small weaning weight in male calves might be due to poor postpartum feeding and more attention for female calves since they are raised for herd replacement.

Conclusion and recommendation

• The production performance of Arsi-HF crossbred in this study was better as compared with that of pure Zebu breeds. However, the production performance of Arsi-HF crossbred in this study was far below the expected genetic potential of animals in the tropical environment elsewhere. This may be attributed to poor feeding, housing health care and breeding management.
  
  
• In the current study, year had an important role in determining the performance of dairy cows indicating that the variation in feed availability and quality as well as variation in management through the years.
  
  
• In order to maintain optimum milk yield, cows with 6th and above parity have to be culled and replaced timely, paying due attention for individual animals with exceptionally higher performance.
  
  
• As it is being called, the farm may not qualify to be a profitable enterprise under the existing condition, but needs further detail assessment of cost benefit analysis.
  
  
• To express their expected genetic potential, the animals may need improved feeding, housing, health care and breeding management.
  
  
• The current result shows that there was no significant difference in production performance among different blood levels. Due to the fact that exotic animals and those with high level of exotic blood are more susceptible to disease and require better care in terms of nutrition, it is not advisable to keep above 50% blood level. However, with better management it is possible to maintain high grade or pure exotic animals.

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Received 4 April 2019; Accepted 23 April 2019; Published 4 June 2019

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