Exploratory study of growth performance of Harar, Ogaden, Arsi, and Jersey × Horro crossbred bulls fed corn silage based finishing diet

Abstract

This exploratory study was conducted to determine the growth performance of bulls from Harar, Jersey×Horro crossbred, Arsi, and Ogaden cattle breeds fed a corn-silage based finishing diet. A total of 12 bulls, 3 from each breed, were used for the study. A completely randomized design (CRD) was implemented to assign experimental bulls in a breed factor arrangement of treatment. The results of the study revealed that the breed of cattle had a significant (p < 0.05) influence on final body weight, change in body weight, and average daily weight gain (ADG). The ADG was higher (p < 0.05) for Harar (0.65 kg/day) and Ogaden (0.63 kg/day) breeds compared to Jersey×Horro crossbred (0.49 kg/day), and Arsi (0.49 kg/day) breed. The body weight was significantly (p < 0.001) and accurately predicted from Heart girth (R² = 94.07%) and body length (R² = 82.50%). From the study, it was concluded that finishing young Ogaden and Harar breeds using corn silage and concentrate can improve growth performance and economic benefit and have attained the weight demand for the export market.

Keywords:

• Cattle breeds
• corn-silage
• cost-benefit
• growth performance

Reviewing Editor:

• Pedro González-Redondo
• University of Seville
• Spain

Subjects:

• Agriculture
• agriculture and food
• plant and animal ecology

Introduction

Ethiopia has approximately 70 million cattle (Central Statistical Authority [CSA], 2021). There is a huge potential for meat production, but the growth performance, meat yield, and net return have been low (Mummed & Webb, 2015; Lemma et al., 2005). The growth performance of meat animals influences the profitability of beef cattle production (Newman & Coffey, 1999). The growth potential of meat animals can be exploited by selection within the breed and improvement in management. The higher growth performance that has been observed for the crossbred bulls in comparison with the indigenous cattle breeds could be due to the influence of breed and heterosis on the growth potential of crossbred cattle between Bos taurus × Bos indicus (Demeke et al., 2003).

In Ethiopia, inadequate meat animal supply, poor growth performance, and inferior body condition of meat animals are among the major issues mainly complained about by exporters of live animals, meat, and meat products (Hailemariam et al., 2008). Moreover, there have been no cattle breeds solely kept for meat production in Ethiopia, which could be due to inadequate research and development on cattle breeds for meat production (Mummed & Webb, 2014). In Ethiopia, meat is produced mainly from cattle used for draft purposes in the traditional production system, and too-old cattle are commonly sold for slaughter without any finishing. As a result, there has been poor quality and low quantity of meat production. Moreover, poor feeding and overall management systems aggravate the problems of the traditional meat animal production system in Ethiopia (Lemma et al., 2005). In addition, the cattle fattening practices were not mainly market-oriented fattening (Zeleke & Getachew, 2017). Improvement of meat animals’ production by applying better feeding and overall management systems is very crucial to enhancing meat production in Ethiopia. Finishing cattle breeds based on concentrate supplementation improved the growth performance of meat animals (Gudeto et al., 2019; Birmaduma et al., 2019; Tefera et al., 2019; Tucho et al., 2018).

Corn silage has been used and is very popular in beef cattle production around the world (Burken, 2014; Keady et al., 2008). Previous studies have confirmed that the inclusion of corn silage in diets improved feed intake and growth performance, implying that corn silage inclusion could promote beef cattle feed intake. It is confirmed that a meat animal’s growth performance has been positively associated with the animal’s dietary concentrate amount (Wei et al., 2018; O’Kiely & Moloney, 2000). The inclusion of corn silage in a mixture with concentrate promoted higher feed intake and better beef cattle growth performance (Zaralis et al., 2014), The concentrate requirement of beef cattle can be reduced by including corn silage in the ration (Keady et al., 2013). It is especially useful when high-quality beef cattle feeds are too expensive (Muhamad et al., 2018). Meat animal fattening is one of the best options for producers to quickly earn returns on improved feed production and utilization (Mengistu, 2002).

Previous research has shown that feed shortage, breed, age, level of stress, feeding system, and overall management factors all affect cattle breed growth performance (Gudeto et al., 2019; Birmaduma et al., 2019; Debele et al., 2015; Guru et al., 2013; Tucho et al., 2018). The authors suggested that the growth performance of some cattle breeds could be enhanced through the provision of improved feeds and feeding systems and overall management. Concentrate supplementation was critical in improving growth performance and increasing revenue from exports of live animals, meat, and meat products (Gudeto et al., 2019; Debele et al., 2015; Guru et al., 2013; Tucho et al., 2018). Few studies targeted the weight demand of the export market for Arsi, Kereyu, and Borana cattle breeds to attain the export market weight demand (250–300 kg) during cattle fattening practices (Gudeto et al., 2019; Debele et al., 2015; Guru et al., 2013; Tucho et al., 2018). However, most of the previous studies didn’t consider the market orientation and weight demand of the export market when evaluating cattle fattening practices. Tender meat supply to the export market was one of the major problems facing the export market in Ethiopia (Mummed & Webb, 2015). Age is one of the factors which affect the quality of meat. Younger animals yield tender meat which becomes tougher as the animal advances in age. As most local cattle breeds reach maturity about four years of age in traditional cattle production, it was widely assumed that cattle younger than 4 years of age would not produce reasonable carcass and meat yield. It was a well-known fact that pre-and post- weaning management of calves influences the slaughter weight of cattle (Mummed & Webb, 2015). There was little documented information on the influence of corn silage and concentrate supplementation on the growth performance of different cattle breeds about 2 years of age in Ethiopia. Some authors have suggested further investigation of the growth performance of cattle under similar feeding systems. Moreover, there was no adequate research conducted on the growth performance and feed conversion efficiency of cattle breeds in Ethiopia. Therefore, the objective of this exploratory study was to evaluate the growth performance of Ogaden, Jersey × Horro crossbred, Harar, and Arsi cattle breeds fed a similar finishing diet based on corn silage and concentrate supplement.

Materials and methods

Description of the study place

The experimental bulls were finished and slaughtered at Haramaya University, which is located about 510 km from the capital city of Ethiopia. It is located at 9° 20’N latitude, 42° 30’E longitude, and an elevation of 2043 m.a.s.l. With 780 mm of average annual rainfall, the minimum and maximum temperatures in the study area were 12.6 and 28.5 °C, respectively.

Experimental cattle breeds management and treatment

To undertake this study, a total of 12 intact bulls of four cattle breeds (3 Harar, 3 Ogaden, 3 Arsi, and 3 Jersey × Horro crossbred) of similar age (2.0–2.5 years) were used for the study. Harar, Arsi, Jersey × Horro crossbred, and Ogaden cattle breeds were purchased from the Chiro cattle market of the west Hararge zone, the Bulbula cattle market of the west Arsi zone, the Shambu campus of Wollega University, and Haramaya University, respectively. At Haramaya University, cows of Ogaden cattle breed were not milked, and milk was exclusively used for the calves while it was assumed that calves of other cattle breeds used in the experiment followed the traditional practice of sharing milk with the producer families. The age of experimental cattle breeds was estimated based on the dentition method described by Meat and Livestock Australia (MLA, 2011). A completely randomised design (CRD) was implemented to assign experimental bulls in a breed factor arrangement of treatment. The diet for experimental cattle breeds was composed of roughage (52%) and concentrate (48%). Out of which corn silage accounts for 20% of the total ration, while grass hay accounts for 32%. The concentrate was composed of 27.8% ground noug cake, 34.78% wheat bran, 33.14% maize grain, 1.7% limestone, 0.88% ruminant premix, and 1.7% salt based on requirements for finishing beef cattle. A ration of concentrate and roughage per head of cattle breeds per day was calculated and offered based on 3% of the live body weight of experimental cattle breeds, and the amount of total feed offered was adjusted based on the change in live body weight once every two weeks. The experimental cattle breeds were kept in individual feeding pens and fed the concentrate twice daily. Water was supplied ad libitum to the experimental cattle breeds during the 10 days adaptation and 90 days fattening periods.

Nutrient compositions of feed resources

The nutrient composition of concentrate and roughage (corn silage and hay) samples were analyzed at the Animal Nutrition laboratory of Haramaya University, Ethiopia. The feed samples were analysed for proximate composition (DM, CP, and Ash) and detergent fibres (NDF, ADF, and ADL). The dry matter (DM) content was determined after drying the feed samples at 105 °C and the ash content after combustion at 550 °C (AOAC, 2000). The Kjeldahl method was used to determine nitrogen (N) (AOAC, 2000). Crude protein was calculated as 6.25 × N, while the detergent fiber content of feeds were analysed and determined by the method described by Van Soest et al. (1991).

Feed intake and conversion efficiency of cattle breeds

The amounts of feed offered and left over were recorded daily. Based on the cattle breeds’ feed intake and live body weight gain, the feed conversion efficiency (FCE) and feed conversion ratio (FCR) were calculated. Feed intake was calculated as the feed offered minus the left over. Feed conversion ratio was calculated as the total weight of feed intake on a DM basis divided per the net weight gain. The daily DM feed intake was calculated as the ratio of the total feed consumed by the experimental cattle (based on the DM basis) to the total number of fattening days.

Growth performance of cattle breeds

The initial, fortnightly, final, and slaughter live body weights of cattle breeds were taken and recorded at the initial, two-week interval, the final day of the experiment, and immediately before the slaughter of the experimental cattle breeds. The average daily weight gain (ADG) was calculated as a change in live body weight per the total length of the finishing period (90 days). A body condition score (BCS) is a method for estimating energy reserves in the form of fat and muscle and determining the relative fatness of beef cattle using a scale of 1 to 9, with a BCS of 1 being extremely thin and a BCS of 9 being extremely obese or over-fattened beef cattle. BCS and live body weight were measured every two weeks (Jaymelynn et al., 2016). The linear body measurement of experimental cattle breeds was measured using the most common linear tape device. Body length was measured from the point of shoulder to the point of rump or pin bone, whereas the circumference or heart girth was measured from a point slightly behind the blade of the shoulder, down the fore-ribs and under the body behind the elbow all the way around. Body height was determined directly on the topline over the hips or hocks. Height at the withers was measured as the distance from the floor of the weighbridge to the withers (Blackmore et al., 1995). The body condition score and linear body measurements of experimental cattle breeds were taken fortnightly (every two weeks).

Statistical analysis

The general linear mixed model procedure allows the capability to address the covariance structure of repeated measures of body weight data directly by using the random mixed model procedure of the SAS System (SAS, 2018). Therefore, for analyzing the data on repeated records of live body weight gain using a linear mixed regression model, two-steps modeling approach were used for the present study. The first-step model and compares the expected value structure by using the general linear mixed method while the second-step model and compares the covariance structure by using the linear mixed regression method (Ngo & Brand, 1997). After determining the best model for the covariance structure in the second step, the analysis of time trends for breed groups was carried out by estimating and comparing means (i.e. tests of fixed effects) using Tukey test (Kenward & Roger, 1997; Spilke et al., 2005). A significant difference among treatments was tested at p < 0.05.

The other model was used to evaluate the influence of cattle breeds on dependent variables such as, feed conversion efficiency, linear body measurements, and body condition scores using Analysis of Variance (ANOVA). This Analysis of Variance (ANOVA) model is indicated below. $$\text{Yik=}\mu \text{+Ai+eik}$$

Whereas Yik = Response or dependent variable such as feed conversion efficiency, linear body measurements and body condition scores. µ = Overall mean. Ai = Cattle Breed Effect (i = 4 breeds, or 3 pure indigenous cattle breeds and 1 crossbreed). eik = random error.

The linear regression was also used for the prediction of the change in body weight as a result of the change in body condition and linear body measurements. The linear regression model was used to predict the change in body weight as a result of a change in body condition and linear body measurements. $$Yi=\alpha +\beta 1X1+\beta 2X2+\beta 23X3+\beta 4X4+\epsilon$$

Whereas Y_i = Dependent variable (live body weight). α = Intercept point. X₁, X₂, X₃ and X₄ = linear body measurement variables (such as heart girth, body length, body height, and height at wither) and body condition. β_1, β_2, β₃ and β₄ = regression slopes of live body weight. ε = residual error.

Partial cost-benefit analysis of cattle fattening

The partial cost-benefit analysis of cattle fattening was done to evaluate the profitability of fattening cattle breeds fed corn silage based on a similar type of finishing diet. The cost of the initial purchase of experimental animals, feed, labour, and drugs were recorded for each experimental cattle breed. The cost of feed was computed from feed intake for a 90-day finishing period and the purchase price of all feed types. The average total variable cost per head of animal (in ETB; 1 ETB = 0.0164 EUR) was formulated by adding all variable costs together, thus only variable costs were used to formulate the total variable cost. At the end of the cattle finishing period, the total gross revenue from each cattle breed was computed based on an estimation of the final selling price of finished experimental animals. To estimate total gross revenue, local cattle market dealers and experts estimated the current market value of each experimental animal. The average total gross revenue (in ETB) per head of animal was formulated from the estimated market prices of local cattle market dealers. Therefore, the average total gross revenue was the final selling price of each animal estimated by market dealers. For each experimental animal, the average total variable cost (ATVC) and average total gross revenue (ATGR) were calculated. By subtracting the average total variable cost from the average total gross revenue, average net revenue (ANR) was calculated. In other words, ANR equals ATGR – ATVC.

Results and discussion

Chemical composition of feed resources

The chemical composition of feed resources offered for experimental cattle breeds is indicated in Table 1. As expected, noug cake and wheat bran had a higher content of CP, whereas corn silage and grass hay had a lower content of CP among the feed resources in the current study. The CP contents of the corn silage and grass hay used for this experiment were an indication of the quality of the corn silage and grass hay. The dry matter (DM) contents of feed resources used in the current study were comparable to the values that were reported in previous studies (Bishaw, 2007; Musa et al., 2021). The DM and CP contents of corn silage obtained in the present study were lower than the values of DM that ranged from 28.5 to 40.5% (Urgesa et al., 2016). The variations in DM and nutrient content of corn silage might be due to the difference in varieties of maize used, maturity stage, and environmental situations (Bernard et al., 2004). The total percentage of ash was higher in noug cake and grass hay than in maize grain. Corn silage and grass hay had higher contents of NDF and ADF than the other feed resources. Grass hay had a higher content of ADL than that of corn-silage. High amounts of NDF and ADF in grass hay were comparable to those reported previously (Bishaw, 2007; Urgesa et al., 2016; Musa et al., 2021).

Table 1. Chemical composition (% on DM basis) of concentrate and roughage offered to experimental cattle breeds.

Ingredients	DM	CP	Ash	NDF	ADF	ADL
Noug cake	92.05	31.41	8.76	46.22	28.24	6.89
Maize grain	88.34	12.97	0.74	36.99	4.67	2.93
Wheat bran	88.78	22.79	6.12	60.81	15.62	5.98
Corn silage	23.56	8.77	6.22	81.40	49.72	5.63
Grass hay	96.45	11.73	7.95	81.27	45.47	13.60

DM: dry matter; CP: crude protein; NDF: neutral detergent fiber; ADF: acid detergent fiber; ADL: acid detergent lignin.

Live body weight and average daily weight gain

The live body weight and change in body weight of cattle breed fed corn silage based on a similar finishing diet over different lengths of feeding periods from day 15 (t15) up to day 90 (t90) are indicated in Table 2. Cattle breeds had a significant (p < 0.05) influence on the final weight and change in live body weight. The average values of final and change in live body weights increased steadily with the length of feeding periods. These different patterns of increase in body weight over time could be explained in terms of the difference in growth performance of the different cattle breeds. The Ogaden (253.22 kg) breed had a higher (p < 0.05) final body weight compared to other experimental cattle breeds. The final body weight was higher (p < 0.05) for Jersey × Horro crossbred (180.33 kg) and Harar breed (189.89 kg) compared to the Arsi (153.89 kg) breed. At the end of the 90-day feeding period, the final body weight was higher (p < 0.05) for the Ogaden breed compared to Jersey × Horro crossbred, Harar, and Arsi breeds. Moreover, the final body weight was higher (p < 0.05) for the Jersey × Horro crossbred and Harar breed compared to the Arsi breed at 90 days of the feeding period.

Table 2. Live body weight (kg) of cattle breeds measured on six consecutive times or feeding periods (t₁₅–t₉₀) post initial body weight (IBW) recording.

DT***	Cattle Breeds
	Arsi	Harar	Ogaden	Jersey × Horro
t15	136.00^c (2.09)	164.33^b (2.97)	227.00^a (7.89)	160.67^b (13.18)
t30	142.33^c (1.46)	171.67^b (3.53)	239.67^a (5.24)	167.67^b (13.40)
t45	148.67^c (2.34)	182.67^b (5.05)	248.0^a (8.55)	174.67^b (15.86)
t60	158.67^c (2.91)	197.00^b (4.05)	260.33^a (7.70)	185.67^b (15.45)
t75	165.00^c (2.89)	207.67^b (5.05)	269.00^a (9.62)	194.67^b (14.88)
t90	172.67^c (5.21)	216.00^b (8.01)	275.00^a (11.08)	198.67^b (15.36)

* $\overline{y} (\mathit{\text{SE}})$ = mean and standard error; ***DT = days-on-test or length of feeding periods, implies the number of days elapsed post initial body weight (IBW) recording at the start of the test. ^a,b,cMeans in the same row with different superscript letters differ significantly at p < 0.05.

The change in live body weight was higher (p < 0.05) for Ogaden compared to other experimental cattle breeds on the length of feeding periods of 15, 30, and 45 days (Table 3). Whereas, the change in body weight was not significantly (p > 0.05) different between Jersey × Horro crossbred and Arsi breed on the length of feeding periods of 15, and 30 days. However, the change in body weight was higher (p < 0.05) for Harar breed compared to Jersey × Horro crossbred and Arsi breed on the length of feeding period of 45 days. The change in body weight was higher (p < 0.05) for Ogaden and Harar breeds compared to Jersey × Horro crossbred, and Arsi breed on length of feeding periods of 60, 75, and 90 days. The change in body weight was higher (p < 0.05) for Harar (58.67 kg) and Ogaden (56.33 kg) breeds compared to Jersey × Horro crossbred (44.33 kg) and Arsi (44.33 kg) breed on 90 days of the feeding period.

Table 3. Change in body weight (kg) of cattle breeds measured on six consecutive times or feeding periods (t₁₅–t₉₀) post initial body weight (IBW) recording.

DT***	Cattle breeds
	Arsi	Harar	Ogaden	Jersey × Horro
t15	7.67^b (1.20)*	7.00^b (0.58)	8.67^a (1.20)	6.33^b (0.34)
t30	14.00^b (1.54)	14.33^b (3.34)	21.00^a (4.17)	13.33^b (3.94)
t45	20.33^c (3.76)	25.33^b (3.18)	29.33^a (7.43)	20.33^c (6.37)
t60	30.33^b (4.10)	39.67^a (1.86)	41.67^a (6.90)	31.33^b (7.36)
t75	36.67^b (3.85)	50.33^a (3.18)	50.33^a (8.36)	40.33^b (6.37)
t90	44.33^b (5.85)	58.67^a (6.57)	56.33^a (8.88)	44.33^b (6.34)

* $\overline{y} (\mathit{\text{SE}})$ = mean and standard error; ***DT = days-on-test or length of feeding period, implies the number of days elapsed post initial body weight (IBW) recording at the start of the test. ^a,b,cMeans in the same row with different superscript letters differ significantly at p < 0.05.

In line with the results of the present study, studies indicate that genotypes of cattle had a significant (p < 0.05) influence on growth performance traits (Demeke et al., 2003; Pereira et al., 2015). According to the authors, cattle breed differences, heterosis, and recombination effects were significant genetic factors influencing the growth performance of Bos taurus x Bos indicus crosses (Demeke et al., 2003). In contrast to these results, Musa et al. (2021) reported that the breed of cattle had a non-significant effect on live body weight and ADG of Borana, Friesian x local crossbred, Harar, and Arsi cattle breeds for the same age group. Some authors also revealed that there were non-significant differences in live body weight and ADG between Borana and Kereyu bulls at 2 years of age fed similar dietary rations for 168 days of fattening duration (Tucho et al., 2018), and yearling Kereyu bulls fed dietary rations for 179 days of fattening duration (Worku et al., 2019). Gudeto et al. (2019) also obtained no significant difference in the final live body weight of yearling Arsi bulls fed dietary rations for 238 days of fattening.

In Table 4, the average daily weight gain (ADG) of cattle breeds fed corn silage based on a similar finishing diet over different lengths of feeding periods from day 15 (t15) up to day 90 (t90) is presented. Cattle breeds had a significant (p < 0.05) effect on average daily weight gain (ADG). ADG was higher (p < 0.05) for the Ogaden breed compared to other experimental cattle breeds on the length of feeding periods of 15, and 30 days. However, ADG was not significantly (p > 0.05) different between Jersey × Horro crossbred, Harar, and Arsi breeds on the length of feeding periods of 15, and 30 days. ADG was higher (p < 0.05) for Ogaden and Harar breeds compared to Jersey × Horro crossbred, and Arsi breed on the length of feeding periods of 45, 60, 75, and 90 days. At the end of the 90-day feeding period, ADG was higher (p < 0.05) for Ogaden (0.63 kg) and Harar (0.65 kg) breeds compared to Jersey × Horro crossbred (0.49 kg), and Arsi (0.49 kg) breed. However, ADG was not significantly (p > 0.05) different between Ogaden and Harar breeds, as well as between Jersey × Horro crossbred and Arsi breed on the length of feeding periods of 45, 60, 75, and 90 days.

Table 4. Average daily weight gain/ADG (kg/head) of cattle breeds measured on six consecutive times or feeding periods (t₁₅–t₉₀) post initial body weight (IBW) recording.

DT***	Cattle breed-group
	Arsi	Harar	Ogaden	Jersey × Horro
t15	0.51^b (0.08)	0.47^b (0.04)	0.58^a (0.08)	0.42^b (0.02)
t30	0.47^b (0.05)	0.48^b (0.11)	0.70^a (0.14)	0.44^b (0.13)
t45	0.45^b (0.08)	0.56^a (0.07)	0.65^a (0.17)	0.45^b (0.14)
t60	0.51^b (0.07)	0.66^a (0.03)	0.69^a (0.12)	0.52^b (0.12)
t75	0.49^b (0.05)	0.67^a (0.04)	0.67^a (0.11)	0.54^b (0.09)
t90	0.49^b (0.06)	0.65^a (0.08)	0.63^a (0.10)	0.49^b (0.07)

* $\overline{y} (\mathit{\text{SE}})$ = mean and standard error; ***DT = days-on-test or length of feeding period, implies the number of days elapsed post IBW recording at the start of the test. ^a,b,cMeans in the same row with different superscript letters differ significantly at p < 0.05.

In a 90-day feeding period, the overall mean value of ADG (0.566 kg/day) of cattle breeds obtained in the present study was comparable with that of ADG (0.57 kg/day) of Borana, Friesian*local crossbred, Arsi, and Harar cattle breeds for the same age group from previous findings (Musa et al., 2021). The results of the ADG of Harar and Ogaden breeds obtained in the present study were comparable with the ADG of Harar (0.68 kg/day), Friesian × local crossbred (0.65 kg/day) and Borana (0.71 kg/day) breeds at a 90-day feeding period. Similarly, the average value of the ADG of Jersey × Horro crossbred and Arsi breed was comparable with the value of the Arsi (0.49 kg/day) breed for the same age group (Musa et al., 2021). The variation in ADG between cattle breeds could be the difference in the genetic potential of the breed. The average daily weight gain of the Arsi (0.49 kg/day) breed obtained in this study was also comparable to the range of ADG of Arsi bulls (0.44–0.57 kg/day) reported in previous results (Tola et al., 2003). In addition, the ADG was comparable with the values of the ADG of Arsi bulls (0.470–0.558 kg/day) fed rations for 238 days of fattening (Gudeto et al., 2019). However, the authors confirmed that yearling Arsi bulls did not attain the demand of the export market for live body weight (250–300 kg) at 238 days of finishing period, which might be associated with the small body size and a short dimension of the skeletal frame of the Arsi cattle breed.

In a 90-day feeding period, the ADG of the Ogaden (0.63 kg/day) cattle breed obtained in this study was higher than the ADG of Ogaden bulls (0.47 kg/day) supplemented with agro-industrial by-products and hay mix in addition to grazing natural pasture from a previous study (Mekasha et al., 2011), and higher than the ADG of Ogaden bulls (0.222 kg/day) for concentrate un-supplemented about 18–24 months of age (Mekuriaw et al., 2009), but lower than the ADG of Kereyu bulls (0.740–0.810 kg/day) of 2 years old supplemented with three dietary rations for 168 days (Tucho et al., 2018). However, the ADG was comparable with the ADG value of the Borana (0.63 kg/day) breed at 4 years old to earlier findings (Bedhane & Dadi, 2016). The variations in average daily weight gain among studies could be related to the type of rations.

In a 90-day feeding period, the ADG of Jersey × Horro crossbreds (0.49 kg/day) obtained in this study was comparable with the average daily weight gain of Jersey weaned calves (0.530 kg/day) fed a maize stover silage based total mixed ration, Jersey calves (0.450 kg/day) fed hay and concentrate (Terefe et al., 2021), and it was higher than the average daily weight gain of Horro steers (0.40 kg/day) supplemented with concentrate in addition to grazing natural pasture as a basal diet (Lemma et al., 2005). However, it was lower than the ADG of Friesian × Horro (0.87 kg/day) crossbred bulls (Merera & Galmessa, 2013), and Friesian × local (0.65 kg/day) crossbred bulls (Musa et al., 2021). The variation in results of average daily weight gain among studies could be due to the difference in growth genetic potential of Jersey and Friesian sire cattle breeds. The authors also indicated that Jersey weaned calves fed the maize stover silage with a total mixed diet had a higher growth performance than those that were fed hay and concentrate (Terefe et al., 2021).

Feed conversion efficiency

The overall mean values of feed conversion efficiency and ratio were 0.199 ± 0.04 and 5.29 ± 1.13, respectively, (Table 5). The average values of feed conversion efficiency and ratio were not significantly (p > 0.05) different among cattle breeds. In line with this result, some authors reported that the feed conversion ratio was not significantly different (p > 0.05) between cattle breeds (Kebede et al., 2013; Musa et al., 2021; Tola et al., 2003). The overall mean value of feed conversion efficiency (0.199) obtained in this study was slightly higher than the value (0.13) obtained in previous studies for Borana, Friesian × local crossbred, Harar, and Arsi cattle breeds of similar age group (Musa et al., 2021), and the values for Borana (0.14) and Arsi (0.13) cattle breeds (Tola et al., 2002). The overall value of the feed conversion ratio (5.29) obtained in the present study was lower than the value of the ratio of feed conversion (7.6) for Kereyu bulls of 2 years of age supplemented with dietary rations from a previous study (Tucho et al., 2018). The variations might be related to the difference in dietary composition and genetic potential of cattle breeds. The lowest feed conversion efficiency indicates the best feed conversion efficiency and a higher kg of weight gain. The results of the study indicate that experimental cattle breeds had shown better feed conversion efficiency.

Table 5. Body condition scores (BCS) and feed conversion efficiency of Arsi, Jersey × Horro crossbred, Harar, and Ogaden cattle breeds.

Body condition scores	Arsi	Harar	Jersey × Horro	Ogaden	Overall Mean ± SE	p-Value
	LSmeans ± SE
Initial body condition (score)	3.33 ± 0.17^c	4.17 ± 0.17^b	3.83 ± 0.17^bc	4.83 ± 0.17^a	4.04 ± 0.17	0.001
Final body condition (score)	5.17 ± 0.17^c	6.33 ± 0.17^ab	5.83 ± 0.44^bc	7.17 ± 0.33^a	6.13 ± 0.25	0.009
Change in body condition (score)	1.83 ± 0.33	2.17 ± 0.17	2.00 ± 0.29	2.33 ± 0.44	2.08 ± 0.15	0.728
Change in body weight (kg)	44.33 ± 2.84	58.67 ± 3.57	44.33 ± 3.33	56.33 ± 4.88	50.92 ± 3.0	0.735
Change in body weight to condition score (kg)	24.58 ± 1.11	27.80 ± 2.78	22.38 ± 1.84	28.09 ± 5.69	25.71 ± 2.64	0.886
FCE	0.215 ± 0.03	0.231 ± 0.02	0.183 ± 0.02	0.164 ± 0.02	0.199 ± 0.04	0.272
FCR	4.78 ± 0.54	4.41 ± 0.46	5.63 ± 0.72	6.33 ± 0.82	5.29 ± 1.13	0.234

^{a –c}Means with different superscript letters within each row are significantly different at p < 0.05. SE is an abbreviation for standard error. FCE and FCR are abbreviations for feed conversion efficiency and ratio, respectively.

Body condition scores

The body condition scores (BCS) of the Harar, Arsi, Jersey × Horro crossbred, and Ogaden cattle breeds are presented in Table 5. The final body condition score was significantly (p < 0.05) different between experimental cattle breeds. The overall mean final body condition score was 6.13. The variations in initial body condition might be related to the difference in the management of cattle breeds before the execution of the experiment. The final body condition was higher (p < 0.01) for Ogaden breed (7.17) compared to Arsi breed (5.17) and Jersey × Horro crossbred (5.83). However, the final body condition score was not significantly (p > 0.05) different between Ogaden (7.17) and Harar (6.33) breeds; and was not significantly (p > 0.05) different between Jersey × Horro crossbred, Arsi, and Harar breeds. The highest body condition indicated the best body reserve (Berry et al., 2006). The average change in body condition score was not significantly (p > 0.05) different between cattle breeds. The overall mean value of the final body condition score (6.13) obtained in the current study was slightly higher than the average value of the final body condition score (5.87) of Borana, Friesian × local crossbred, Harar, and Arsi breeds of similar age group from earlier results (Musa et al., 2021). The variation in final body condition could be related to the feed conversation ratio.

The change in body condition of meat animals is an indirect prediction of change in body weight (Berry et al., 2006). In the present study, the ratio of change in body weight to body condition was not significantly (p > 0.05) different between experimental cattle breeds (Table 5). In contrast to the results of the present study, the breed of cattle had a significant influence on the ratio of change in body weight to change in body condition (Musa et al., 2021). A ratio of change in body weight to change in body condition was higher (p > 0.05) for Ogaden (28.09 kg) and Harar (27.80 kg) breeds and lower for Jersey × Horro crossbred (22.38 kg). These results of the ratio of change in body weight to change in body condition obtained in the present study were higher than the values reported for Harar (22.42 kg), Arsi (20.61 kg), and Borana (20.3 kg) bulls, whereas as comparable with the values for Friesian × local crossbred (27.78 kg) results of the previous study (Musa et al., 2021). The highest ratio of change indicates the best suitable breed for fattening.

Linear body measurements

Linear body measurements of Arsi, Harar, Jersey × Horro crossbred, and Ogaden cattle breeds are indicated in Table 6. The breed of cattle had a significant influence on final heart girth, body length, and height at wither. The average value of final heart girth was higher (p < 0.05) for the Ogaden breed (160.33 cm) and lower (p < 0.05) for the Arsi breed (132.67 cm). Both Jersey × Horro crossbred and Harar breed had a lower (p < 0.05) in values of final heart girth than Ogaden and higher (p < 0.05) than Arsi breed, but there was no significant (p > 0.05) difference in values of final heart girth between Jersey × Horro crossbred and Harar breed. Similar to the heart girth of the results of the present study, an average heart girth of 148.2 ± 14.31 cm was reported for Ogaden bulls less than four years of age (Mekuriaw et al., 2009).

Table 6. Linear body measurements of Arsi, Jersey × Horro crossbred, Harar, and Ogaden cattle breeds.

Linear body measurement (cm)	Arsi	Harar		Jersey × Horro		Ogaden	Overall Mean ± SE	p-Value
	LSmeans ± SE
Initial heart girth	126.00 ± 1.00^c	134.00 ± 3.06^b	134.33 ± 2.19^b		147.33 ± 1.86^a		135.42 ± 2.48	0.001
Final heart girth	132.67 ± 1.76^c	141.67 ± 0.88^b	141.00 ± 3.51^b		160.33 ± 2.33^a		143.92 ± 3.21	0.001
Change in heart girth	6.67 ± 1.86	7.67 ± 2.33	6.67 ± 1.33		13.00 ± 0.58		8.50 ± 1.06	0.076
Initial body height	96.33 ± 0.88	107.0 ± 4.58	107.67 ± 6.77		108.0 ± 3.21		104.75 ± 2.39	0.259
Final body height	102.67 ± 0.60	118.00 ± 7.91	116.50 ± 7.08		120.67 ± 3.19		114.46 ± 3.16	0.178
Change in body height	6.33 ± 1.48	11.0 ± 3.33	8.83 ± 2.20		12.67 ± 2.46		9.71 ± 1.27	0.356
Initial body Length	106.33 ± 2.96	110.33 ± 3.67	115.67 ± 2.33		117.67 ± 0.88		112.50 ± 1.76	0.061
Final body Length	115.33 ± 1.86^c	122.33 ± 2.6bc	124.33 ± 2.73^b		132.33 ± 2.33^a		123.58 ± 2.09	0.007
Change in body Length	9.00 ± 1.15	12.00 ± 2.08	8.67 ± 2.19		14.67 ± 1.45		11.08 ± 1.05	0.130
Initial wither height	93.33 ± 0.67^c	97.33 ± 0.88^b	99.33 ± 1.33^b		105.0 ± 1.73^a		98.75 ± 1.37	0.001
Final wither height	100.83 ± 1.01^c	106.17 ± 1.3bc	110.33 ± 2.96^b		116.67 ± 0.88^a		108.5 ± 1.90	0.001
Change in wither height	7.50 ± 0.50	8.83 ± 1.83	11.00 ± 1.73		11.67 ± 2.60		9.75 ± 0.93	0.401

^{a –c}Means with different superscript letters within each row are significantly different at p < 0.05. SE is an abbreviation for standard error.

The final body length was higher (p < 0.01) for the Ogaden breed (132.33 cm) compared to other experimental cattle breeds. Jersey × Horro crossbred (124.33 cm) and Harar (122.33 cm) breed were longer (p < 0.01) in final body length compared to the Arsi (115.33 cm) breed, but there was no significant (p > 0.05) difference in final body length between Jersey × Horro crossbred and Harar breed. The average final body length obtained in this study was higher than the average body length of Ogaden bulls (120.4 ± 7.27 cm) less than four years of age from the previous study (Mekuriaw et al., 2009).

The average values of final wither heights were higher (p < 0.05) for Ogaden (116.67 cm) and lower (p < 0.05) for Arsi (100.83 cm) breed. Both Jersey × Horro crossbred (110.33 cm) and Harar (106.17 cm) breed had a higher (p < 0.05) in final wither heights than the Arsi breed, but there was no significant (p > 0.05) difference in final wither heights between Jersey × Horro crossbred and Harar breed. The average final wither height of Ogaden and Arsi breeds obtained in the present study was comparable with the average wither height of Ogaden bulls (115.5 cm) under four years of age (Mekuriaw et al., 2009), and with the average wither height of Arsi (110 cm) breed from the previous study (Albero & Haile-Mariam, 1992), respectively.

Prediction of body weight from linear body measurements and body condition

The prediction regression equation of live body weight from linear body measurements and body conditions is indicated in Table 7. Heart girth (R² = 94.07%) and body length (R² = 82.50%) significantly (p < 0.05) and accurately predicted live body weight. Live body weight was also significantly (p < 0.05) predicted from wither height (R² = 49.44%). It means that 94.07 and 82.50% of the change in live body weight were correctly predicted from heart girth and body length, respectively. The linear regression equation for the prediction of live body weight (Y) from heart girth (X) was Y = −334.37 + 3.28 (heart girth). It indicates that an increase of 1 cm in heart girth resulted in an increase of 3.28 kg in body weight of experimental cattle breeds. In line with this equation, Patel et al. (2019) obtained a regression equation of Y = −125.16 + 2.05 (heart girth) with the highest coefficient of determination (R² = 95.2%) of live body weight from the girth of Friesian crossbred cattle, indicating an increase of 1 cm in heart girth resulted in an increase of 2.048 kg in live body weight of Holstein-Friesian crossbred cattle. The result of an increase in heart girth resulted in an increase of body weight in the present finding was comparable with the result of an increase of 3.4–4.7 kg of live body weight for Ethiopian highland oxen (Goe et al., 2001) and 3.37 kg of body weight for Bos indicus in Kenya (Odadi, 2018), but lower than an increase of 4.83 kg of live body weight for cattle breeds with 2–3 years from the previous study (Musa et al., 2021).

Table 7. Linear regression equation for prediction of live body weight from linear body measurements and body condition score.

Prediction equation	R^2	MSE	p-Value
Y= −334.37 + 3.28 (Heart girth)	94.07	10.30	<.001
Y= −438.91 + 5.29 (Body length)	82.50	18.53	<.001
Y= −274.55 + 4.52 (Wither height)	49.44	31.54	0.011
Y = 12.65 + 1.77 (Body height)	21.13	39.39	0.132
Y= −334.37 + 3.28 (Heart girth) + 0.124 (Body height) − 1.09 (Wither height) + 1.47 (Body length)	94.31	10.08	<.001
Y= −316.97 + 3.70 (Heart girth) (Optimal prediction equation)	94.07	10.30	<.001
Y= −35.23 + 40.95 (Body condition score)	73.00	23.05	0.001
Y= −313.74 + 6.59 (Body condition) + 2.81 (Heart girth) −0.053 (Body height) −0.86 (Wither height) + 1.48 (Body length)	96.78	10.28	0.001
Y= −294.32 + 6.62 (Body condition) + 3.26 (Heart girth)	95.18	10.26	<.001
Y= −6.29 + 44.25 (Body condition) −0.429 (Body height)	73.76	23.95	0.002
Y= −344.41 + 19.73 (Body condition)+ 3.55 (Body length)	90.56	14.36	<.001
Y= −200.37 + 32.25 (Body condition)+2.01 (Wither height)	79.52	21.16	<0.001

* Optimal prediction equation was computed after removing the non-significant variables from the model.

A higher prediction coefficient of (R² = 94.07%) body weight from heart girth obtained in the present study was comparable with the prediction coefficient of (R² = 95.2%) body weight from heart girth of Friesian crossbred (Patel et al., 2019) and the prediction coefficient of (R² = 96.3%) for Sahiwal cattle observed by Bhagat et al. (2016) but higher than the prediction value (R²= 81%) from the previous study (Musa et al., 2021). The highest coefficients of the determination indicate that the linear regression equation including heart girth in the model could be sufficient to predict the body weight of Sahiwal cattle (Bhagat et al., 2016) and Friesian crossbred from heart girth from earlier findings (Patel et al., 2019). The body weight was predicted significantly (p < 0.05) from body condition and its combination with linear body measurements, with regression prediction coefficient ranging from 73.0 to 96.78%. Body condition and heart girth (R² = 95.18%) were predicted significantly (p < 0.05) and accurately body weight. Linear regression equation for the prediction of live body weight (Y) from body condition and heart girth was Y = −294.32 + 6.62 (Body condition) + 3.26 (Heart girth). This prediction equation is very crucial because body condition is the most important trait in determining the price of cattle in the domestic market.

Partial cost-benefit analysis of cattle fattening

A partial cost-benefit analysis of fattening Arsi, Harar, Jersey × Horro crossbred, and Ogaden cattle breeds supplemented concentrate with corn silage and hay as a basal diet is indicated in Table 8. From the results of the partial cost-benefit analysis of this study, the average net revenue was higher for Ogaden (7387.25 ETB), followed by Jersey × Horro crossbred (4836.77 ETB), and Harar (4197.42 ETB) breed, and the lowest for Arsi (1492.97 ETB), indicating the Ogaden breed has good potential for fattening and generates better gross net revenue followed by Jersey × Horro crossbred and Harar breed. The variation in net revenue might be related to the difference in growth performance, feed conversion ratio, body conformation, and condition between cattle breeds. In line with this results, a higher average net revenue was obtained for Borana (7380.47 ETB) and followed by Harar (5406.86 ETB) breed and Friesian × local crossbred (3384.98 ETB) from the previous study (Musa et al., 2021), and net revenue of 5338.00, 4666.30, and 4841.00 ETB per head of the bull was also reported for two-year old Kereyu bulls fed three different diets composed of concentrate and hay as the basal diet (Tucho et al., 2018). However, a higher net return was obtained in this study compared to the net return from Horro steers (663.30 ETB per head of steer) supplemented with noug cake and maize with hay as the basal diet from a previous study (Lemma et al., 2005). The variation in net revenue between the studies might be related to the difference in the price of total variable cost, body conformation and condition, visual estimation of the total revenue of cattle breeds, age, and breed of cattle.

Table 8. Partial cost-benefit analysis of fattening Arsi, Jersey × Horro crossbred, Harar, and Ogaden cattle breeds fed corn silage based similar finishing diet.

Cost-benefit variables	Cattle Breeds
	Arsi	Harar	Jersey × Horro	Ogaden
Initial purchase cost/bull (ETB)	9733.33	10833.33	10100.00	14000.00
Feed cost/bull (ETB)	3840.37	4435.92	4563.23	6112.75
Labour cost/bull (ETB)	500.00	500.00	500.00	500.00
Drug cost/bull (ETB)	200.00	200.00	200.00	200.00
Total variable cost/bull (ETB)	14,273.70	15,969.25	15,363.23	20,812.75
Total Gross revenue/bull (ETB)	15,766.67	20,166.67	20,200.00	28,200.00
Net revenue/bull (ETB)	1492.97	4197.42	4836.77	7387.25

* Only variable costs were considered for this cost-benefit analysis of fattening. ETB is an abbreviation for Ethiopian Birr (1 ETB = 0.0164 EUR).

From the results of the partial cost-benefit analysis of the present study, the fattening of the Ogaden breed, followed by Jersey × Horro crossbred and Harar breed using supplementation of concentrate with corn silage, was more economically profitable, whereas the net revenue was low for the fattening of Arsi breed. In agreement with the net revenue results, the previous study indicates that finishing Borana, followed by the Harar breed, was more profitable (Musa et al., 2021). However, in contrast to the net revenue from Jersey × Horro crossbred fattening in the present study, a previous study reveals that fattening of Friesian × local crossbred was less profitable, which might be related to the high feed intake of Friesian × local crossbred compared to indigenous cattle breeds (Musa et al., 2021). The results indicate that finishing Ogaden, Jersey × Horro crossbred, and Harar breeds could be more advisable to increase net benefit.

Conclusions and recommendation

From the results of the present exploratory study, the breed of cattle had a significant (p < 0.05) influence on final live body weight, change in live body weight, and average daily weight gain (ADG). At the end of the 90 days feeding period, the ADG was higher for Harar and Ogaden breeds compared to Jersey × Horro crossbred and Arsi breed, indicating the possibility of improving the performance of young bulls finished on corn silage and concentrate supplements. The Ogaden breed had better feed conversion efficiency compared to other experimental cattle breeds. The average net revenue was higher for Ogaden, followed by Jersey × Horro crossbred, and Harar breed. From the results of this study, it was concluded that Ogaden and Harar breeds had shown better growth performance, body condition, net revenue, and attainment of acceptable weight at a younger age, which can meet export market demand for the quality of meat. Therefore, the finishing of Ogaden and Harar breeds using corn silage-based finishing diets should be applied to improve the growth performance of meat animals and enhance the net revenue for producers. Further studies should be conducted to identify whether the pre-weaning management and/or the genes of the breed were the main reasons for the better performance of Ogaden breed finished on corn silage-based diet in the present study.

Authors contributions

CME: Proposal development, formal presentation, investigation, data collection and analysis, writing and editing; YYM, AAM, MYK, MTG, TGO: Investigation, data analysis, validation, supervision, writing, review and editing.

Acknowledgements

The corresponding author wants to extend thanks to Ambo University for covering salary during the study period and some aspect of the research. All authors wish to thank the United States Agency for International Development (USAID) for financially support of the research work.

Disclosure statement

The authors declared that there is no conflict of interest between authors and organizations regarding this paper.

Data availability statement

Data will be available based upon reasonable request data policy.

Additional information

Funding

This research was financially supported by the United States Agency for International Development (USAID) Bureau for Food Security under [Agreement # AID-OAA-L-15-00003] as part of Feed the Future Innovation Lab for Livestock Systems for funding this research.

Notes on contributors

Chala Merera Erge

Chala Merera Erge graduated with a Master of Science in Animal Production from the Hawassa University, Ethiopia. He has extensive research and community service experience. He has also implemented national and international projects in collaboration with different scholars. Currently, he is a PhD student in Animal Production at Haramaya University, Ethiopia. His research interest focuses on animal production.