Livestock Research for Rural Development 30 (9) 2018 Guide for preparation of papers LRRD Newsletter

Citation of this paper

On-station growth performance evaluation of Small East African and dual purpose goat breeds in Northern Tanzania

E Hyera, M E Mlimbe, J D Sanka1, M G Minja, A P Rugaimukamu, P M Latonga, E G Mbembela, A S Nguluma, Z C Nziku, M S H Mashingo1 and E J M Shirima

Tanzania Livestock Research Institute, West Kilimanjaro Centre, PO Box 147, Sanya Juu, Kilimanjaro, Tanzania.
ehyera2004@yahoo.co.uk
1 Ministry of Livestock and Fisheries (MLF), PO Box 9152, Dar es Salaam, Tanzania

Abstract

The objective of this study was to compare the effects of breed, sex, birth type, age of the dam and year of kidding on pre weaning growth traits of Pare White, Sonjo Red and Blended goat kids under on-station management system. Records of 616 kids born between 2008 and 2017 were analyzed using General Linear Model procedures. The results of this study revealed that Blended kids were superior to Pare White and Sonjo Red for all growth traits (p<0.001). Pare White kids were heavier than Sonjo Red at birth (p<0.01), but no difference was observed in their weaning weight and average daily gain (p>0.05). Blended, Pare White and Sonjo Red kids weighed 3.11 0.09 kg, 2.52 0.10 kg and 2.29 0.11 kg at birth, respectively and 10.2 0.29 kg, 7.51 0.32 kg and 7.31 0.35 kg at weaning, respectively, while their average daily gain was 60.4 2.27 g/day, 45.4 2.50 g/day and 44.4 2.66 g/day, respectively. Males were superior to females across all traits (p<0.01). Single and multiple births did not differ in birth weight (p>0.05). Also, singles and triplets did not differ in weaning weight and average daily gain (p>0.05). But, singles grew faster and were heavier than twins at weaning (p <0.001). Kids born to does aged below three years had lighter weight in all three traits compared to kids born to does aged three to eight years ( p<0.01). Year of kidding had a significant effect on pre weaning growth traits (p<0.05). Pare White kids ranked second in performance after Blended kids. Thus, Blended and Pare White goats can be a source of genetic material for improving performance of SEA goats in semi-intensive and extensive production systems. The entire results intensify knowledge of factors influencing variation in growth traits and management of animals.

Key words: blended, Pare White, pre weaning growth, Sonjo Red


Introduction

Goat production is amongst the foremost agricultural activities in Tanzania, which sustain the livelihoods of smallholder farmers, pastoral and agro pastoral communities (URT 2011). Goat population is approximately 16.7 million with over 97% of them are indigenous breed subtypes belonging to the Small East African (SEA) breed (URT 2015). SEA breed subtypes are named after locations or societies keeping them (Chenyambuga et al 2004), for instances, Ujiji goats are found in Ujiji town in the western zone, near Lake Tanganyika whereas Newala goats are found in Newala district in the southern part of Tanzania. Pare White and Sonjo Red goats are originally raised in areas, which are predominantly inhabited by Pare and Sonjo (Batemi) societies, respectively, in the northern zone of Tanzania (Nguluma et al 2016). This naming system does not reveal the actual diversity of the strains (Chenyambuga et al 2004).

SEA goats adapt well to the semi-arid tropical conditions and East African climate, can withstand diseases, heat and drought stresses (Njombe and Msanga 2011). They are widely distributed to almost all agro-ecological zones in the country and have a strong potential to significantly contribute to household income and other socio-cultural importance (Chenyambuga and Lekule 2014). Yet, there are great variations in production traits of SEA goats, which brand a high possibility for utilizing the most performing and adapted animals for each environment to improve the performance traits. Thus, the existing differences within SEA goat strains must be identified for breeding and breed improvement purposes (Philipsson et al 2011).

Research efforts have led to the development of dual purpose goat breed popularly known as Blended or Malya goats (URT 2011). Blended goat is a composite breed, which was developed and stabilized in late 1960s at Malya Livestock Research Centre in Lake Victoria zone in Tanzania. It is composed of 30% Boer of South Africa, 55% Kamorai of Pakistan and 15% Tanzania indigenous goat’s blood (Das et al 1996). It was proven for large body size, excellent body conformation, higher multiple births, fast growth rate, good carcass quality, considerable milk yield and sound adaptation to the semi-arid tropical climate (Das and Sendalo 1990; Shirima 2005). According to Das et al (1996), the breed has been kept mainly for meat production. Besides, due to its productive performance, it is used in comparison performance studies with indigenous and other improved goat breeds, to estimate viability of the most economically important traits of meat animals. Therefore, the objective of this study was to compare the variation in pre weaning growth traits of Pare White, Sonjo Red and Blended goat kids reared in semi-intensive management system at West Kilimanjaro Livestock Research Centre in the northern zone of Tanzania.


Material and methods

Description of the study area

The experiment was carried out at the Tanzania Livestock Research Institute, West Kilimanjaro Centre in Northern Tanzania. The Centre is found at 3S latitude and 39E longitude, at an altitude of about 1270 meters above sea level. The farm represents part of the northern Tanzania, which has typical semi-arid climatic condition, however, with bimodal rainfall. Annual average rainfall lies between 450 – 700 mm, which is inadequate to sustain growth of pasture forage resources. Temperature ranges between 11.7 0C – 27.8 0C. The soils are mainly dark brown and silt loam with enormously poor moisture holding capacity due to its deficiency in organic matter. Natural pastures are mainly dominated by Cencrus ciliaris grass species.

Experimental animals

The research included a total of 616 kids of both sexes (326 males and 290 females) born between 2008 and 2017 during long rains season. The kids consisted of 248 Pare White, 210 Sonjo Red and 158 Blended breed types. The animals were managed in semi-intensive breeding conditions.

Animal management

The mating season started from Mid-October to Mid-December and the kidding season was from March to May. Does were exposed to bucks at a ratio of 20 to 25 does to one buck and kidded while grazing and browsing on pasture forage resources. Mating groups were herded cautiously to ensure no mixing of the breeding flocks at any time. At birth, kids were ear tagged for identification and weighed at 12 to 24 hours after birth. Kids suckled their dams and were also allowed ad libitum feeding of greenish succulent pasture forages during the day from the age of one month. Water and mineral blocks were available ad libitum. Concentrate supplementation was done during pasture shortage period. All animals were sheltered in wooden houses with raised floors (Plate 1). Kids were also weighed at weaning when the median kid age was approximately 112 days.

Plate 1. Kids of SEA and dual purpose goat breeds nurtured in loose houses with raised wooden floor (A) Pare White (B) Sonjo Red and (C) Blended
Data collection and statistical analysis

Data collection was mainly on kid growth traits. Birth dates, breed, sex, birth type and birth weights were recorded at kidding. Kid weights at birth and weaning were taken using the Salter weighing scale, model 235 6S. The average daily gain of kids was calculated as the difference between weaning weight and their birth weight, divided by the weaning age. The General Linear Model procedures of SAS version 9.1 for Windows (SAS, 2004) was used to analyze the data using the following model equation: Yijklm = + Bi + Sj + Tk + A1 + Y m + eijklm; Where Yijklm = record for the trait measured, = general mean, Bi = fixed effect of the ith breed type of the kid (i: 1 = Pare White, 2 = Sonjo Red, 3 = Blended), Sj = fixed effect the jth sex of the kid (j: 1 = male, 2 = female), Tk = fixed effect of the kth type of birth (k: 1 = single, 2 = twins, 3 = triplets), A 1 = fixed effect of the lth age of the dam (l: 1 = below 3 years, 2 = 3 – 5 years, 3 = 6 – 8 years, 4 = ≥ 9 years), Ym = fixed effect of the mth year of kidding (m: 1 = 2008, 2 = 2010, 3 = 2011,………, 9 = 2017) and eijklm = random residual effect associated with the ijklm th observations.


Results and discussion

Mean with standard error for the effect of breed on birth weight, weaning weight and pre weaning average daily gain of SEA and Blended goat kids are presented in Table 1. Pare White kids weighing 2.52 0.10 kg at birth were observed to be heavier (p<0.01) than Sonjo Red kids, which weighed 2.29 0.11 kg. Birth weight and average daily gain of Pare White and Sonjo Red kids observed in this study were lower than those reported for SEA goats in Kenya by Ahuya et al (2002). Also, it was observed that weights at birth and weaning of SEA goat kids in this study were higher than those reported for SEA (Teso) kids in North-eastern Uganda reported by Ssewannyana et al (2004). However, Teso kids were gaining 47.2 3.28 g/day, which was higher than values for Pare White and Sonjo Red kids observed in this study. According to Ssewannyana et al (2004), higher average daily gain observed in Teso kids might be due to a combination of inherent growth potential, good mothering ability of dams and rapid adaptation to the natural environment.

Blended kids having 3.11 0.09 kg birth weight, 10.2 0.29 kg weaning and 60.4 2.27 g/day average daily gain were observed to be heavier than Pare White and Sonjo Red kids from birth to weaning (p<0.001). The birth weight of Blended kids observed in this study was higher than values reported by Lyatuu et al (1992) at Kongwa Pasture Research Centre in central Tanzania and Das et al (1996) at Malya Livestock Research Centre in Lake Victoria zone in Tanzania. However, the weaning weight observed in this study was lower than values reported at Kongwa and Malya. Superiority in growth traits of Blended kids is due to the reason that it is a composite breed, which has combined the blood of Boer and Kamorai goats both of which are large breeds. Boer goat in South-eastern US (Browning et al 2004) and moderate wet region of North-western Croatia (Duricic et al 2012) was reported to weigh 3.21 0.09 kg and 3.48 0.04 kg, respectively, at birth due to better management. However, Lehloenya et al (2005) reported a lower birth weight by approximately 0.90 kg in semiarid and arid areas of South Africa.

Table 1. Least Squares Means (± se) effect of breed on birth and pre weaning growth of SEA and Blended goat kids

Traits

Breed

p-value

Pare White

Sonjo Red

Blended

Birth weight (kg)

2.52 ± 0.10b

2.29 ± 0.11c

3.11 ± 0.09a

0.01

Weaning weight (kg)

7.51 ± 0.32b

7.31 ± 0.35b

10.2 ± 0.29a

0.001

Average daily gain (g)

45.4 ± 2.5b

44.4 ± 2.66b

60.4 ± 2.27a

0.001

Within row, within each trait, means without common superscripts differ significantly at p<0.05, se = Standard error

Male kids were heavier than females and grew faster from birth to weaning (Table 2). This finding agrees with the report for various breeds of goats by Das and Sendalo (1992), Lyatuu et al (1992), Das et al (1996), Ahuya et al (2002), Ssewannyana et al (2004), Zahraddeen et al (2008), Mioč et al (2011), Duricic et al (2012), Nugroho et al (2018) to name a few. The higher birth weight in male kids than in females is due to inherent genetic potential, which increases the rate of pre-natal growth in males (Nugroho et al 2018). Dissimilarities in sex chromosomes in the position of genes related to growth, physiological characteristics and endocrine variations such as the type and measure of hormone secretion particularly sex hormone result to difference in animal growth (Mohammadi et al 2010). In relation to endocrinal function between two sexes, estrogen hormone has partial effect on the growth of long bones in females (Rashidi et al 2008). The higher average daily gain in males suggests that naturally, the male sex acclimatizes to the environment more rapidly (Zhang et al 2009).

Table 2. Least Squares Means (± se) effect of sex on birth and pre weaning growth of SEA and Blended goat kids

Traits

Sex

p-value

Male

Female

Birth weight (kg)

2.72 ± 0.10a

2.56 ± 0.09b

0.0093

Weaning weight (kg)

8.79 ± 0.30a

7.89 ± 0.30b

<.0001

Average daily gain (g)

52.9 ± 2.33a

47.5 ± 2.31b

0.0001

Within row, within each trait, means without common superscripts differ significantly at p<0.05, se = Standard error

In the current study, single and multiple births did not differ in birth weight (Table 3). Also, singles and triplets did not differ in weaning weight and average daily gain (p>0.05). But, singles were observed to grow faster and were heavier than twins at weaning (p <0.001). Other scholars (Das and Sendalo 1992; Lyatuu et al 1992; Das et al 1996; Ahuya et al 2002; Ssewannyana et al 2004; Zhang et al 2009; Browning and Leite-Browning 2011; Deribe and Taye 2013; Deribe et al 2015) reported a higher growth performance of single kids when compared with twin and triplet kids across all traits, which are common observations in goats. The higher birth weight in singles than twins might be due to the influence of pre-natal maternal effect such as inter-uterine space and nutrients (Zahraddeen et al 2008). Robinson et al (1977) reported that an increase in number of fetuses in utero decreases the number of caruncles attached to each fetus, which causes reduced feed supply to the fetuses resulting to physiological starvation and reduction in the birth weight of the multiples. Also, Gardner et al (2007) stated that as litter size increases individual birth weights decline due to the finite capacity of the maternal uterine space to gestate offspring. The higher weaning weight and average daily gain of single kids than twins in the current study might be because they are sole users of the entire milk from their dam while twin kids need to strive for milk suckling (Deribe and Taye 2013).

Table 3. Least Squares Means (± se) effect of birth type on birth and pre weaning growth of SEA and Blended goat kids

Traits

Birth type

p-value

Single

Twins

Triplets

Birth weight (kg)

2.53 ± 0.09a

2.55 ± 0.11a

2.50 ± 0.07a

0.05

Weaning weight (kg)

8.83 ± 0.21a

7.56 ± 0.28b

7.53 ± 0.24b

0.001

Average daily gain (g)

54.6 ± 2.21a

44.8 ± 2.58b

44.9 ± 2.77b

0.001

Within row, within each trait, means without common superscripts differ significantly at p<0.05, se = Standard error

The results of this study showed that kids born to does aged below three years old had lighter weight in all three traits compared to kids born to does aged three to eight years (Table 4). Browning and Leite-Browning (2011) observed that kids born to does aged two years old had lower birth weight and weaning weight compared to kids from does aged three years, but the influence of dam age on average daily gain was not evident. However, Das et al (1996) observed significant influence of dam age on average daily gain up to 48 weeks of age. Zahraddeen et al (2008) reported lower weights of kids from lower parities. Similarly, Bemji et al (2006) observed that the live weight of kids was increased with parity of does. Lighter weights for kids of does aged less than three years old might be associated with smaller does at kidding and low mothering ability. Younger does are not at their mature weight; hence, the partitioning of nutrients to complement their growth and growth of their fetuses might have contributed to lighter kids at birth (Browning et al 2011). Also, lower milking capacity of the maiden does might have contributed to lighter weaning weight and average daily gain of their kids (Deribe and Taye 2013).

Table 4. Least Squares Means (± se) effect of age of the dam on birth and pre weaning growth of SEA and Blended goat kids

Traits

Age of the dam

p-value

Below 3 years

3 – 5 years

6 – 8 years

≥ 9 years

Birth weight (kg)

2.25 ± 0.13b

2.74 ± 0.08a

2.70 ± 0.09a

2.87 ± 0.22ab

0.01

Weaning weight (kg)

7.15 ± 0.41b

9.02 ± 0.25a

8.88 ± 0.27a

8.30 ± 0.69ab

0.001

Average daily gain (g)

45.0 ± 3.14b

55.5 ±1.95a

54.4 ± 2.11a

46.0 ± 5.28ab

0.001

Within row, within each trait, means without common superscripts differ significantly at p<0.05, se = Standard error

Year of kidding had a significant effect on pre weaning growth traits (Table 5). Kids born in 2008 had the lowest birth weight (2.10 0.13 kg), but the difference was not significant when compared to kids born in 2011, 2015 and 2017 (p>0.05). Still, they had the lowest weaning weight (5.75 0.40 kg) and average daily gain (33.9 3.11kg) compared to kids born in the other years (p<0.05). Kids born in 2013 and 2012 had the highest birth weight (3.86 0.12 kg) and weaning weight (11.0 0.40 kg), respectively. The highest average daily gain (58.3 2.99 g/day) was obtained in 2014. Low performance of kids born in 2008 might be due to prolonged drought condition observed in 2007/2008 (Keyyu 2014). The extended critical feed shortage at the farm prior to and during pregnancy might have caused nutritional stress that might have resulted in loss of dams’ body weight, obstruction of fetal growth due to placental deficiency and lighter birth weight and post-natal weight gain in kids (Deribe et al 2015). Variations between years might be partly due to variations in rainfall that influence pasture production and availability of forage resources, management problems primarily due to insufficient resources to deal with several husbandry practices like supplementary feeding and dissimilarities in sample size (Nugroho et al 2018).

Table 5. Least Squares Means (± se) effect of year of kidding on birth and pre weaning growth of SEA and Blended goat kids

Factor

Level

Traits

Birth weight (kg)

Weaning weight (kg)

Average daily gain (g)

Year of kidding

2008

2.10 ± 0.13f

5.75 ± 0.40f

33.9 ± 3.11e

2010

2.39 ± 0.12de

8.58 ± 0.38cd

51.7 ± 2.94c

2011

2.24 ± 0.12f

7.37 ± 0.36e

47.0 ± 2.79cd

2012

3.33 ± 0.13b

11.0 ± 0.40a

62.1 ± 3.08a

2013

3.86 ± 0.12a

10.2 ± 0.39b

52.6 ± 2.99bc

2014

2.70 ± 0.12c

9.21 ± 0.39c

58.3 ± 2.99ab

2015

2.28 ± 0.15ef

7.72 ± 0.47de

51.2 ± 3.64cd

2016

2.57 ± 0.13cd

7.44 ± 0.41e

45.4 ± 3.15d

2017

2.30 ± 0.14ef

7.70 ± 0.44e

49.7 ± 3.35cd

p -value

0.05

0.05

0.05

Within column, within each trait, means without common superscripts are significantly different at p<0.05, se = Standard error


Conclusion


Conflicts of interest

The authors declare that no conflicts of interest exist for the work presented in this article.


Acknowledgement

The authors acknowledge the Ministry of Livestock and Fisheries of the Government of Tanzania due to its financial and material support for the accomplishment of this research work. Authors also convey sincere appreciation to supporting staff of the West Kilimanjaro Livestock Research Centre due to their diligent participation in herd management.


References

Ahuya C O, Okeyo A M, Mosi R O, Murithi F M and Matiri F M 2002 Body weight and pre-weaning growth rate of pure indigenous, Toggenburg goat breeds and their crosses under smallholder production systems in Kenya. In: Proceedings of Responding to the increasing global demand for animal products, UADY, Merida, Yucatan, Mexico, British Society of Animal Science, Midlothian, UK., 85-86.

Bemji M N, Osinowo O A, Ozoje, M O, Adebambo O A and Aina A B J 2006 Live weight changes during lactation and its relationship with milk off take and yield in West African Dwarf and Red Sokoto goats intensively managed within the humid zone of Nigeria. Nigerian Journal of Animal Production, 33(1): 145-150.

Browning R Jr, Kebe S H and Byars M 2004 Preliminary assessment of Boer and Kiko does as maternal lines for kid performance under humid, subtropical conditions. South African Journal of Animal Science, 34 (Supplement 1).

Browning R Jr and Leite-Browning M L 2011 Birth to weaning kid traits from a complete diallel of Boer, Kiko and Spanish meat goat breeds semi-intensively managed on humid subtropical pasture. Journal of Animal Science, 89 (9): 2696-2707. https://doi.org/10.2527/jas.2011-3865 Accessed on April 19, 2018

Browning R Jr, Leite-Browning M and Byars M Jr 2011 Reproductive and health traits among Boer, Kiko, and Spanish meat goat does under humid, subtropical pasture conditions of the southeastern United States. Journal of Animal Science, 89: 648–660. https://doi.org/10.2527/jas.2010-2930 Accessed on April 17, 2018

Chenyambuga S W, Hanotte O, Hirbo J, Watts P C, Kemp S J, Kifaro G C, Gwakisa P S, Petersen P H and Rege, J E. O 2004 Genetic characterization of indigenous goats of sub-saharan Africa using microsatellite DNA markers. Asian-Australasian Journal of Animal Sciences, 17(4): 445-452 https://www.ajas.info/journal/view.php?doi=10.5713/ajas.2004.445 Retrieved April 19, 2018

Chenyambuga S W and Lekule F P 2014 Breed preference and breeding practices for goats in agro-pastoral communities of semi-arid and sub-humid areas in Tanzania. Livestock Research for Rural Development, Volume 26, Article # 117. http://www.lrrd.org/lrrd26/6/chen26117.html Retrieved April 20, 2018

Das S M and Sendalo D S C 1990 Comparative performance of improved meat goats in Malya.Tanzania Small Ruminants Research and Development in Africa. In: Proceedings of the First Biennial Conference of the African Small Ruminant Research Network. ILRAD, Nairobi Kenya. 10-14 December 1990, pp. 445-452.

Das S M and Sendalo D S 1992 Comparative performance of improved meat goats in Malya, Tanzania In: Rey B. Lebbie S H B and Reynolds L (eds), Small ruminant research and development in Africa. Proceedings of the First Biennial Conference of the African Small Ruminant Research Network, ILRAD, Nairobi, Kenya, 10-14 December 1990. ILCA (International Livestock Centre for Africa), Nairobi, Kenya. pp. 445-452.

Das M S, Rege J E O and Mesfin S 1996 Phenotypic and genetic parameters of growth traits of Blended goats at Malya, Tanzania. In. Proceeding of the Third Biennial Conference of the African Small Ruminant Research Network, UICC, Kampala, Uganda, pp. 326

Deribe B and Taye M 2013 Growth performance and carcass characteristics of Central Highland goats in Sekota district, Ethiopia. Agricultural Advances, 2(8): 250-258.

Deribe B, Tilahun M, Lakew M, Belayneh N, Zegeye A, Walle M, Ayichew D, Ali S T and Abriham S 2015 On-station growth performance of crossbred goats (Boer X Central Highland) at Sirinka, Ethiopia. Asian Journal of Animal Sciences, 9(6): 454-459. https://scialert.net/abstract/?doi=ajas.2015.454.459

Duricic D, Grizelj J, Dobranic T, Harapin I, Vince S, Kocila P, Folnozic I, Lipar M, Gracner G G and Samardzija M 2012 Reproductive performance of Boer goats in a moderate climate zone. Veterinarski Arhiv, 82(4): 351-35.

Gardner D S, Buttery P J, Daniel Z and Symonds M E 2007 Factors affecting birth weight in sheep: maternal environment. Reproduction, 133(1): 297-3 07.

Keyyu J D 2014 Climate change and climate variability in Tanzania: The case of the Kilimanjaro region. In: Proceedings of the 3rd International Conference on Earth Science and Climate Change, San Francisco, USA 28-30 July, 2014.

Lehloenya K C, Greyling J P C and Schwalbach L M J 2005 Reproductive performance of South African indigenous goats following oestrus synchronisation and AI. Small Ruminant Research, 57, 115-120.

Lyatuu E T R, Das S M and Mkonyi J I 1992 Some production parameters of Blended goats in semi-arid regions of Tanzania. In: Proceedings of the Second Biennial Conference of the African Small Ruminant Research Network AICC, Arusha, Tanzania 7-11 December 1992.

Mioč B, Sušić V, Antunović Z, Prpić Z, Vnuč ec I and Kasap A 2011 Study on birth weight and pre weaning growth of Croatian multicolored goat kids. Veterinarski arhiv, 81(3): 339-347

Mohammadi K, Beygi-Nassiri M T, Fayazi J and Roshanfekr M 2010 Investigation of environmental factors influence on pre-weaning growth traits in Zandi lambs. Journal of Animal and Veterinary Advances 9: 1011 – 1014.

Nguluma A S, Msalya G and Chenyambuga S W 2016 Phenotypic variation among four populations of Small East African goats of Tanzania. Livestock Research for Rural Development, Volume 28, Article # 136. http://www.lrrd.org/lrrd28/8/ngul28136.html

Njombe A P and Msanga Y 2011 Livestock and dairy industry development in Tanzania. http://www.mifugo.go.tz

Nugroho T, Nurhidayati A, Ayuningtyas A I, Kustiyani C, Prastowo S and Widyas N 2018 Birth and weaning weight of kids from different Boer goat crosses. IOP Conference Series: Earth and Environmental Science, Vol. 142, conference 1

Philipsson J, Rege J E O, Zonabend E and Okeyo A M 2011 Sustainable breeding programmes for tropical farming systems In: Ojango J M, Malmfors B and Okeyo A M (Eds) Animal Genetics Training Resource, version 3, 2011. International Livestock Research Institute, Nairobi, Kenya, and Swedish University of Agricultural Sciences, Uppsala, Sweden

Rashidi A, Mokhtar M S, Jahannshahi A S and Abadi M R M 2008 Genetic parameter estimates of pre-weaning growth traits in Kermani sheep. Small Ruminant Research, 74: 165-171.

Robinson J J, McDonald I, Fraser C and Crafts R M J 1977 Studies on reproduction in prolific ewes. 1. Growth of the products of conception. Journal of Agricultural Science, 88: 539-552.

SAS 2004 Statistical Analysis Systems, SAS User Guide for Personal Computers, Statistical Program, release 9.1 SAS Institute Inc., Cary, NC.

Shirima E J M 2005 Benefits from dual purpose goats for crop and livestock production under small-scale peasant systems in Kondoa eroded areas, Tanzania. Livestock Research for Rural Development, Volume 17, Article # 138 http://www.lrrd.org/lrrd17/12/shir17138.htm Retrieved April 08, 2018

Ssewannyana E, Oluka J and Masaba J K 2004 Growth and performance of indigenous and crossbred goats. Uganda Journal of Agricultural Sciences, 9: 537-542. Available on: https://www.ajol.info/index.php/ujas/article/view/135512 Accessed on April 11, 2018

URT 2011 United Republic of Tanzania-Tanzania. Livestock Sector Development Programme, Ministry of Livestock and Fisheries Development, Dar es Salaam, Tanzania

URT 2015 United Republic of Tanzania-Tanzania livestock modernization initiative (TLMI), Ministry of Livestock and Fisheries Development, Dar es Salaam. Tanzania

Zahraddeen D, Butswat I S R and Mbap S T 2008 Evaluation of some factors influencing growth performance of local goats in Nigeria. African Journal of Food, Agriculture, Nutrition and Development, 4: 464-479. Available on: https://www.ajol.info/index.php/ajfand/article/view/19206 Accessed on April 11, 2018

Zhang C, Zhang Y, Xu D, Li X, Su J and Yang L 2009 Genetic and phenotypic parameter estimates for growth traits in Boer goat, Livestock Science. 124: 66-71.


Received 27 June 2018; Accepted 23 July 2018; Published 3 September 2018

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