**2.1 Description of on-station data**

322 A Bird's-Eye View of Veterinary Medicine

appropriate breeding and production technologies for improving production and

The overall objective of the study was to evaluate and document the performance of existing breeds of cattle in the south western agro-ecological zone (SWAEZ) for improved livestock productivity. The specific objectives include: (i) to evaluate the growth performance of

The study is meant to generate up to-date and accurate information on performance of selected cattle populations in the SWAEZ in terms of their growth, maturity and production parameters. This would help in packaging of appropriate information on better management practices to guide farmers in partnership with National Agriculture Advisory Services (NAADS) and extension workers as conduits for effective uptake pathways for

A longitudinal study involving growth data collection from Ankole, Friesian, Friesian cross, Boran and Boran crosses was conducted. Growth data on-station and on-farm from the experimental animals was collected over a period of three years (July 2006 to June 2009) and

The on farm study was conducted in the districts of Kiruhura, Ibanda and Sembabule. In Kiruhura district, the sub-counties of Kikatsi and Sanga were involved. In Ibanda district, Nyabuhikye and Kikenkye sub-counties were involved. In Sembabule the studies were

On-station the studies were conducted at Mbarara Zonal Agriculture Research and Development Institute (ZARDI) found in Mbarara district. It involved taking bi- weekly (i.e. fortnightly) weights using the heart girth tape. The heart girth tape was graduated in both cm and kg. Both measurements were taken but for purposes of analysis, only weight values were used. There was a high and positive correlation between heart girth and body weight of cattle (Oluka, 2006). Individual study animals were identified using the ear tag numbers for effective continuous monitoring. Animals were restrained in the crush and weighed

The sample sizes varied from district to district. In Kiruhura district, the study animals were 141, Ibanda district, 182 and in Sembabule district 189. Calves below the age of three months were identified and randomly selected and tagged for the study. Only farmers who were willing to participate in the study were recruited and involved in the study. The farmers willingly gave the number of animals requested for the study. More Female animals were preferred because they were normally kept for longer periods by the farmers and were not easily sold. In contrast the male were sold off at any age to meet the financial needs of the

Under on-station management, a total of 30 Ankole cattle and 35 Friesian cattle were recruited for the study. Unlike the on-farm cattle, parameter measurement and data collection started immediately after birth of calves by taking and recording birth weights

farmers e.g. paying school fees, meet family health care needs or provide food.

productivity of various cattle breeds in Uganda.

technology adoption.

**2. Materials and methods** 

using the heart girth tape.

and there after bi-weekly.

existing cattle breed under on-station and on-farm conditions.

9 months from October 2008 to June 2009 respectively.

conducted in Lugusulu and Migwala sub-counties.

On-station data involved only two cattle breeds i.e., the pure (100%) Friesian and the pure (100%) Ankole cattle. The weights were taken immediately after birth. The sample sizes were 30 Ankole cattle and 35 Friesian cattle. Continuous recording of heart girth and body weight measurements was done every two weeks for a period of 3 years. The data was, however entered in Excel at interval of 30 days i.e. monthly 1 for period 1-30 days, period 2 for 31-60 days, etc. All calves were managed under similar conditions allowing suckling up to 6 months while their dams were on open free range grazing management under the care a herdsman. Comparison was based on fixed effects under a single management of one onstation site focussing on breed differences.

Prior to the analysis of variance (ANOVA), a simple descriptive statistical analysis was done to examine the distribution of weight data structured at 30-day intervals for distribution of the means. Those values showing gross errors and outlying were excluded from the data set to avoid adversely affecting the means and hence, standard deviations, variances and standard errors. This was achieved using VIEWTABLE, GPLOT and MEANS procedures of SAS, version 9 (2002). The GPLOT showed the distribution of observations against the different time intervals of 30 day means.

#### **2.1.1 Analysis models**

ANOVA using General Linear Model (GLM) (SAS, 2000) for calf body weight was performed to determine the fixed effects of various factors on body weight at 30-day intervals from the first month of birth to 12th months of age (360 days of age ). The data was classified according to the experimental variables covering the twelve periods 1-30, 31-60, 61-90, 91-120, 121-150, 151-180, 181-210, 211-241, 241-270, 271-300, 301-330 and 331-360 days (Table 1).

Various analyses were run for different combination of the fixed effects and effects with non-significance levels of P>0.05 dropped from the next test model until the final model was developed. After final adjustments for the various differences and exclusions of nonsignificant effects such as year of birth and multiple births and interaction of cattle breed with season of birth, the final model (i) below was arrived at. This includes only the effect of breed, sex of calf and season of birth (model i) below.

$$\mathbf{Y}\_{ijkl} = \boldsymbol{\mu} + \mathbf{B}\_i + \mathbf{X}\_j + \mathbf{S}\_k + \mathbf{e}\_{ijkl} \tag{i}$$

Where:

Y*ijklm* = the live weight of the lth calf born under ith calf cattle breed, jth sex of calf and kth season of birth.

*µ* = the common parameter (konstant) **B***i* = the fixed effect of breed of cattle (i = 1, 2)

The Growth Performance Evaluation of Cattle

Where:

**calves** 

of birth and lth district of birth

**e***ijklm* = the random residual effect

**3. Results and discussions** 

the results by Said at al., 2001 and Kugonza *et al*., 2005.

*µ* = the common parameter (konstant) **B***i* = the fixed effect of breed of cattle (i = 1, 2) **X***j* = the fixed effect of sex of calf (j = 1, 2) **S***k* = the fixed effect of season of birth (k =1, 2) **D***l* = the fixed effect of district of birth (l =1, 2, 3)

Breeds in the South Western Agro-Ecological Zone (SWAEZ) of Uganda 325

Various analyses were run for different combinations of the fixed effects. Those effects with non-significance levels at P>0.05 were dropped from the next test model until the final model was developed. After final adjustments for the various differences and exclusions of non-significant effects such as year of birth, farmer herd and interaction of cattle breed with season of birth, the final model (i) below was arrived at; that included the fixed effects of

Y*ijklm* = *µ* + **B***i* + **X***<sup>j</sup>* + **S***k* + **D***l* + e*ijklm* (ii)

Y*ijklm* = the live weight of the mth calf born under ith calf cattle breed, jth sex of calf, kth season

**3.1 Genetic group effect on body weight and daily gain for on-station and on-farm** 

On station there was significant effect of breed on body weight of the cattle between month 1 and 2, then between the later months from month 7 to 12 (Tables 1a and 1 b). The birth weights of the Friesian calves were higher than that of the Ankole (Table 2a). There was no significant difference in growth weight of both the Friesians and the Ankole up to six months. After the age of 6 months, the Ankole grew faster than the Friesian. This was attributed to the weaning shock that was experienced by the Friesian calves versus the Ankole that continued to suckle their dams. This is clearly illustrated in Fig. 1. This therefore explained the weight variation between the Friesian and Ankole after six months as illustrated in figure1. Animal used on the station were composed of an old stock that had been breeding for along time without replacement of bulls. This apparently introduced some element of inbreeding depression on the herd. The inbreeding could be an important factor that could be used to explain the variation in the growth rate. Furthermore, disease prevalence and worm burden were present on station; however, the Friesian calves were more susceptible to the diseases than the Ankole calves. The Friesian calves were intensively kept in paddocks compared to the Ankole calves which were moving with their dams. This increased the chances for the Friesian calves to pick worm eggs. These findings are similar to

On farm the study found out that there was significant relationship between breed and growth rate (p<0.05) from the first month to the ninth months as illustrated in table 3a and 3b. The growth weight of the Boran was much higher than for the Boran x Ankole crosses and Friesian x Ankole crosses respectively. This could be explained by the fact that the Borans had great potential for growth intensity traits, have high feed conversion efficiency,

breed, sex of calf, season of birth and district of birth (model ii) below.

**X***j* = the fixed effect of sex of calf (j = 1, 2) **S***k* = the fixed effect of season of birth (k =1, 2) **e***ijkl* = the random residual effect

## **2.2 Description of on farm cattle data**

Cattle handling varied from farmer to farmer depending on availability of handling structures. In some cases the animals were put in a crush, restrained and weight measurement taken using the heart girth tape. In other cases, individual animals were restrained manually by field assistants using ropes. The heart girth and weight estimates were taken using the tape when the animal was calmed down and standing in an upright and straight position. The measurements were immediately recorded in field data sheets. Thereafter, the data was transferred into Excel for back up, collation and analysis.

On-farm data involved 4 genetic breeds of cattle including pure Ankole and Boran crossbred Friesian and Boran. It was, however difficult to determine the exact level of the crossbred animals. At the start of the field study, the calves that were 3 months old were recruited for measurements. However, with time, calves were born among the herds of the participating farmers. The measurements of such calves were recorded within the first month of birth. The heart girth and weights were again taken at the time of the next visit. This was done on monthly intervals though, in some cases, delays could occur due to late release of operational funds. The sample sizes were however larger than on-station with Kiruhura district offering 141 animal records, 182 in Ibanda district and 189 in Sembabule . Continuous recording of heart girth and body weight estimates was done for only 9 months due to the heavy expense and limited funding. All data was entered in Excel at 30 days intervals i.e. period 1 for 1-30 days, period 2 for 31-60 days, etc. All calves were managed under similar conditions allowing suckling up to 8-12 months or at the time when the farmers observe that the cow is nearing to calve down again. All experimental animals from the selected participating farmers were on free range management system under herding. The comparison was based on fixed effects under a free range management focussing on four cattle breed differences, that is Ankole, Boran, Boran x Ankole , and Friesian x Ankole.

Prior to the ANOVA was employed to examine the distribution of live body weight data structured at 30-day intervals. Those values whose means showed gross errors and outlying were excluded from the data set to avoid adversely affecting the means, standard deviations, variances and standard errors. This was achieved again by applying the VIEWTABLE, GPLOT and MEANS procedures of SAS (2002). The GPLOT showed the distribution of observations against the different time intervals of 30 day means.
