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| Photo 1. Abergelle goat flock | Photo 2. Boer cross Abergelle goat flock |
| Livestock Research for Rural Development 26 (1) 2014 | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
This study was undertaken to evaluate the pre and post weaning growth of F1 crossbred Boer-Abergelle goat kids, and reproductive performance of pure Abergelle under a semi-intensive management system. The study was implemented in Abergelle Agricultural Research Centre goat farm in northern Ethiopia. Three independent variables: namely birth type, sex and parity number and seven dependent variables: body weight (BW), weaning weight (WW), six-month weight (SMW), yearling weight (YW) and weight gains to weaning, six months and one year were analyzed. A total of 166 F1 kids of which 90 were from the first parity, 53 from the second and 23 from the third parity were used to evaluate the growth rate of the crossbred kids.
Yearling weights of the crossbred kids were higher for males than for females. The highest values for WWG, SMWG and YWG were observed in the first parity. Average kidding interval of the Abergelle goats was 11.3 months with a minimum and maximum of 9 and 17 months, respectively. Prolificacy rates were 1.06, 1.11 and 1.07 in 2009, 2010 and 2011, respectively. Generally, Boer-Abergelle F1 kids had high growth rates (range 73 to 113 g/day) and had low mortality, especially pre-weaning. Purebred Abergelle goats had long kidding interval and most had single births.
Key words: crossbreeding, growth, mortality, reproductive performance
Goats are the earliest domesticated species and rank as one of the important meat animals in the world (Penn State 2000; Galal 2005). In Ethiopia there are a number goat breeds that have good potential for meat production (Simret 2005). However, low emphasis is given in the overall management aspect and genetic improvement of the indigenous breeds.The present productivity of goats is very low. This low level of productivity in Ethiopian goats could be attributed to disease, lack of proper management, poor nutrition and low emphasis given to genetic improvement. Genetic improvement has been a fundamental part of the many goat development programs in the tropics, where breeding policies mostly aimed to upgrade local goats by crossbreeding with either temperate or tropical exotic breeds (Lavaraj and Gore 1987).
Cross breeding is an easy way to get very productive goats within a short period of time. It is also the easiest way to acquire superior stock from elsewhere. Such a breeding scheme is preferred in development programs to attain the desired goal. Breed selection is also very important to improve the genetic potential of a given breed. But breed improvement through selection is a slow process.
Boer goats are meat type breed that originated in South Africa and have been introduced to different countries of the world including Ethiopia. They have good resistance to disease and adapt well to hot, dry, semi-desert conditions (http://en.wikipedia.org/wiki/Boer_goat#Crossbreeding). In Ethiopia, this breed has been used in crossing with the indigenous goat breeds to improve their productivity. The Abergelle goat breed is one of the breeds that is used for crossing with Boer goats.
Abergelle goat breeds are kept mainly for meat production. In addition to this, these goats are also kept for manure production, cash income and skin production. They have an importnat contribution in improving the household nutrition. When Abergelle goat breeds are compared with Boer goat breeds, they have great differences in their body weight and growth rate. As a result, crossing of Abergelle goats with Boer goats is becoming an important method to improve meat productivity of indigenous goat breeds. The crosbred (F1) can get important traits from their parents that enable them to better resist disease and harsh environments.
The objective of this study was to evaluate the reproductive performance of the Abergelle goat breed and growth rate of the first filial generation (F1) of Boer-Abergelle crossbreds (Photos1 and 2).
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| Photo 1. Abergelle goat flock | Photo 2. Boer cross Abergelle goat flock |
The study was conducted at the Abergelle Agricultural Research station, Ethiopia which is situated at13o 14' 06" N latitude and 38o 58' 50" E longitude. The area is categorized as hot to warm sub-moist lowland (SM1-4) sub-agro ecological zone of the region with an altitude of 1300-1800 m above sea level. The mean annual rainfall ranges from 299 to 650 mm and is characterized by low, erratic and variable rainfall. The mean annual temperature ranges from 28 to 40oC. The area is known for its large livestock population especially goats. There are a total number of 23,501 goats, 91,848 sheep, 73,465 cattle, 201 camels, 18,841 equine, 13,7750 poultry, 56 pigs and 13,317 honey bee colonies (WOARD 2012). The main crops are sorghum, maize, sesame, teff (Eragrostis tef), cow pea, check pea, lentil, and limited amounts of barley and oil seed crops. are produced in the area.
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| Figure 1. Map of the study area |
Abergelle mature female goats (n = 113) were purchased from the local market (Yechila) in 2008. Thereafter, the animals were housed in the barn of the research center. Two pure Boer male goats were introduced to the center for crossbreeding purpose in 2008 with help of Ethiopian sheep and goat productivity improvement program project.
Both the does and kids were de-wormed using Albendasole at the end of the wet season and beginning of the rainy season.They were sprayed with diazinone against the external parasites three times in a year. The does and kids were also vaccinated against anthrax, pasteurellosis and pest des petits ruminants (PPR) which are common diseases of the area. From June to December (when pasture is available) the does grazed for 6 hours per day on natural pasture around the vicinity of the research center; after grazing they had free access to grass hay and water. The rest of the year they were confined and fed grass hay ad libitum. The lactating does also received 400 g/day of wheat bran; dry does were fed 200 g/day. In each case the supplement was given in two equal feeds morning and evening.
From birth up to four months of age, kids were suckled by their dams two times per day in the morning (8:00 am) and evening (5:00 pm). They also received a supplement of 100 g/day of wheat bran and had free access to grass hay starting from three weeks of age up to weaning at 4 months. After 4 months the supplement of wheat bran was increased to 200 g/day. After weaning, the kids had access to pasture (June to December) for 6 hours per day then they were confined and fed grass hay. From January to May they were confined day and night and fed grass hay.
Birth weight (BW, weaning weight (WW), six month weight (SMW) and yearling weight (YW) were recorded in the morning before grazing and watering. All weight measurements except BW were taken at two week interval using the Salter scale with capacity of 50kg and 200g precision. In this study data from 2009 to 2011 were used for analysis but 2012 was also included in the data for kid mortality. From the total of 166 kids; 90 kids in the first parity, 53 in the second parity and in the third parity, were used for analysis. Out of the 166 F1 kids 102 of them were females.
The BW, WW, SMW and YW, the weight gains of the kids at different ages and age at puberty, were taken as dependent variables. Sex, parity number and birth type were taken as independent variables.The data were analyzed using statistical software in SAS (2002). Means were compared using the Tukey test. The statistical model was;
Yijk=m+Pi+Sj +Bk +eijk
where
Yijk = response variables
m = Overall mean
Pi = i theffects of parity (i= 1, 2, 3)
Sj= jth effect of sex (j= male and female)
Bk=kth effect of birth type (k= single and twin)
eijk = Random error (residual effect)
Parity 1 kids had better growth indices to 6 months than kids from parity 2 and 3 (Table 1). This finding is contrary to most published results which indicate that kid growth performance improves with parity (Dadi et al 2008; Belay and Mengistie 2013; Wright et al 1975; Stobart et al 1986; Gurmej et al 1987).
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Table 1. Effect of parity on live weight and gained weight of the Abergelle cross Boer goat kids (n=90 inP1, 53 in P2 and 23 in P3) |
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P1 |
P2 |
P3 |
SEM |
p |
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BW (kg) |
2.89b |
2.73b |
3.21a |
0.044 |
0.0027 |
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WW (kg) |
16.5a |
13.3c |
14.8b |
0.189 |
<0.0001 |
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SMW (kg) |
20.9a |
17.8b |
18.9b |
0.233 |
<0.0001 |
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YW (kg) |
28a |
26.03b |
28.2a |
0.288 |
0.003 |
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WWG (g) |
113a |
88.4b |
97.3c |
1.45 |
<0.0001 |
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SMWG (g) |
100a |
83.7b |
87.2b |
1.23 |
<0.0001 |
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YWG (g) |
69.8a |
64.7b |
69.5ab |
0.763 |
0.008 |
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Means with different letters are different at P<0.05; |
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BW=birth weight; WW=weaning weight; SMW=six months weight; YW=yearling weight; WWG=weaning weight gain; SMWG= six months weight gain; YWG=yearling weight gain; P= Parity |
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Female Boer-Abergelle crossbred kids had slower growth rates and a greater age at puberty than male kids (Table 2). In all growth parameters, single birth kids performed better than twins (Table 3). In agreement with this finding, Belay and Mengistie (2013) reported that single birth kids had faster growth rate than kids from multiple births. Alula et al (2013) also reported that kids born as singles were heavier than twins and triplets
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Table 2 . Effect of sex (n=64 for males; 102 for females) on live weight change and age at puberty of the Abergelle cross Boer goat F1 kids |
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Male |
Female |
SEM |
p |
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BW (kg) |
2.98 |
2.82 |
0.091 |
0.079 |
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WW (kg) |
15.5 |
15.1 |
0.385 |
0.337 |
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SMW (kg) |
20. |
19.2 |
0.473 |
0.019 |
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YW (kg) |
29.6 |
26.1 |
0.527 |
<0.0001 |
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WWG (g) |
104 |
102 |
2.98 |
0.055 |
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SMWG (g) |
96.3 |
91.1 |
2.50 |
0.036 |
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YWG (g) |
73.8 |
64.6 |
1.40 |
<0.0001 |
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AP (months) |
7.62 |
8.22 |
0.183 |
0.0013 |
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AP= Age at puberty |
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Table 3 . Live weight change of the Abergelle cross Boer goat Fl kids with different birth type (singles n=144; twins n=22) |
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Single |
Twin |
SEM |
p |
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BW(kg) |
2.99 |
2.19 |
0.044 |
<0.0001 |
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WW (kg) |
15.5 |
13.8 |
0.189 |
0.003 |
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SMW (kg) |
19.9 |
18.0 |
0.233 |
0.007 |
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YW(kg) |
27.0 |
25.4 |
0.288 |
0.005 |
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WWG (g) |
104 |
96.8 |
1.45 |
0.093 |
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SMWG (g) |
93.9 |
88.1 |
1.23 |
0.111 |
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YWG (g) |
68.7 |
64.4 |
0.763 |
0.053 |
Reproducive rate in the Abergelle does was relatively low in consecutive years (2009 to 2011) with only 9% of twin births and kidding interval almost 12 months (Table 4). However, these data may not be typical of the Abergelle breed as in a previous research survey conducted by Jemal (2008) the kidding interval was 7.87 months. The longer kidding interval seen in this study is likely to be due to low ratio of bucks to does (1:50) and poor plane of nutrition. The does were largely dependent on low quality pasture and scarce availability of browse plants, while the hay supplement was of poor quality.
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Table 4 . Kidding interval (KI) and litter size of Abergelle goats in the three consecutive years |
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2009 |
2010 |
2011 |
SEM |
p |
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KI (months) |
11.5 |
11.4 |
10.9 |
0.118 |
0.114 |
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Litter size |
1.06 |
1.11 |
1.07 |
0.0192 |
0.523 |
Mortality of the F1 kids in all except the 4th parity was higher post- than pre-weaning (Table 5). This could have been the result of a lower nutritional plane after weaning as suckled milk was replaced by poor quality grazing.
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Table 5: The number of new born and mortality rate of Abergelle cross Boer goat F1 kids at different parity number |
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Kid mortality |
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Parity |
Kids |
Pre-weaning |
Percent |
Post- weaning |
Percent |
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First |
95 |
1 |
1.05 |
15 |
15.8 |
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Second |
60 |
3 |
5 |
12 |
20 |
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Third |
39 |
5 |
7.69 |
9 |
23.1 |
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Fourth |
29 |
6 |
20.7 |
1 |
3.45 |
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Average |
223 |
15 |
6.73 |
37 |
16.6 |
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The authors would like to thank Dr. Yayneshet Tesfay, Mr.Tikabo Gebremariam and Dr. Zelealem Tesfay for their constructive comments and technical support. The authors would also like to thank the Abergelle Agricultural Research Center staff members for their cooperation in data recording and animal management.
Alula Petros, Kassaye Aragaw and Berhanu Shilima 2013 Pre-weaning kid mortality in Adamitulu Jedokombolcha District, Mid Rift Valley, Ethiopia . Journal of Veterinary Medicine and Animal Health 6:1-6
Belay Deribe and Mengistie Taye 2013 Evaluation of Growth Performance of Abergelle Goats under traditional management systems in Sekota District, Ethiopia. Pakistan Journal of Biological Sciences, 16: 692-696
Dadi H, Duguma G, Shelima B, Fayera T, Tadesse M, Woldu T and Tucho T A 2008 Non-genetic factors influencing post-weaning growth and reproductive performances of Arsi-Bale goats. http://www.lrrd.org/lrrd20/7/dadi20114.htm
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PennState 2000 Agriculture alternatives: meat goat production. http://agalternatives.aers.psu.edu/livestock/meatgoat/meatgoat.pdf .
SAS 2002 JMP-5 Statistical Software, Version 5.Cary, NC, USA.
Simret Betsha 2005 Supplementation of Graded levels of Peanut cake and wheat bran mixiture on nutrient utilization and carcuss parameters of Sumali goats. Animal MSc Thesis presented to the school of graduate studies of Alamaya University, Ethiopia. pp. 60.
WOARD 2012 Annual report, Wereda Office of Agriculture and Rural Development, Yechilla, Tigray, Ethiopia
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Received 16 August 2013; Accepted 23 December 2013; Published 1 January 2014