Assessment of genetic diversity and relationship of the two Sanga type cattle of Botswana based on microsatellite markers.

The study was performed to evaluate genetic variation on two Sanga type cattle found in Botswana: Tswana and Tuli using twelve microsatellite markers. All amplified loci were polymorphic with 75 and 77 alleles genotyped in the Tswana and Tuli populations, respectively. The total number of alleles per locus ranged from 2 (BM1818) to 10 (TGLA227) with total mean of 6.25 for Tswana and 6.43 for Tuli population. Almost all the markers showed high polymorphic information content (PIC) apart from BM1818 (0.375) and INRA23 (0.393) which were moderately informative in Tswana population. Most of the markers were in Hardy-Weinberg equilibrium except for CSSRM60 and CSSM66 loci in Tswana population and ETH10, ETH225 and CSSM66 loci in Tuli population. A total of 103 unique alleles were genotyped across the two breeds with 49-shared, and 26 and 28 were unique to Tswana and Tuli populations, respectively. The expected heterozygosity (He) values were higher than the observed heterozygosity (Ho) in both populations: Tswana (He = 0.7895 ± 0.033 vs Ho = 0.631 ± 0.091) and Tuli (He = 0.8123 ± 0.033 vs Ho = 0.556 ± 0.021). The inbreeding coefficient was 0.200 ± 0.002 and 0.332 ± 0.001 in Tswana and Tuli populations, respectively. Analysis of molecular variance revealed 6.8% of the total genetic variation corresponding to differences between the two breeds and 93.2% within populations. The genetic identity between the two breeds was 56% and there were similar levels of multilocus heterozygosity and allelic diversity in the two breeds. The use of Tswana and Tuli breeds in a crossbreeding programme is likely to result in minimal heterosis and therefore not recommended.

Population structure of indigenous southern African goats based on the Illumina Goat50K SNP panel.

In this study, the genetic structure of indigenous Tswana and Swazi goats using the Illumina Goat50K SNP array was investigated. Two South African commercial goat breeds were included to investigate admixture with the indigenous populations in southern Africa. A total of 144 DNA samples including Boer goats (n = 24), Kalahari Red (n = 24), Swazi (n = 48), and Tswana goats (n = 48) were genotyped. Statistical analysis was performed using PLINK version 1.07. Genetic diversity, measured as expected heterozygosity, was estimated at 0.390, 0.398, 0.413, and 0.387 for Boer, Kalahari Red, Tswana, and Swazi goats, respectively. The individual inbreeding coefficient varied from 0.019 ± 0.05 to 0.011 ± 0.06 for the Tswana and Swazi goats, respectively. The Principal component analysis clustered the populations according to geographical origin and breed type. Linkage disequilibrium (LD) for shorter intervals (0-10 kb) ranged from 0.44 to 0.56 and commercial breeds had higher values. Effective population sizes decreased with generations and at the 13th generation ranged between 87 for Boer to 266 for Tswana goats. The Tswana population exhibited the highest level of genetic variation and effective population size, which holds potential for improved production in marginal regions. A national strategy is required to maintain genetic diversity in communal goat production systems through well-structured breeding and conservation programs.

A survey analysis of indigenous goat production in communal farming systems of Botswana.

A total of 153 communal farmers in four agro-ecological regions of Botswana were interviewed using a structured questionnaire. The aims of the survey were to characterise existing communal goat production systems, evaluate the importance of goats to farmers and identify breeding practices and constraints encountered in goat production in Botswana. Data was collected on socio-economic parameters, general and breeding management practices and major constraints limiting goat production in Botswana. All respondents were small-scale communal farmers with 63% respondents practising mixed crop-livestock farming and 37% keeping livestock as their primary activity. The majority (33%) of respondents were older than 60 years. Over 80% of the farmers kept goats for cash required for tuition, school uniforms and household commodities as well as re-stocking of animals. Most farmers (62%) kept indigenous crossed genotypes. Generally, uncontrolled mating was practised with the majority of farmers (41%) using on-farm reared bucks for more than two years of breeding and communal bucks (36%) as an alternative. The major constraints limiting goat productivity in communal areas included uncontrolled breeding, predators, theft and diseases. Issues raised by farmers should be considered in designing and implementing effective breeding programs for goats to improve their overall productivity and contribution to poverty alleviation in these communities.

Chemical composition of Mopane worm sampled at three sites in Botswana and subjected to different processing.

Effects of site and degutting on chemical composition of mopane worm were investigated. Samples were cooked for 30 min in either brine or in plain water. Samples from Moreomabele were high in acid detergent fibre (ADF) (P < 0.05) and acid detergent insoluble nitrogen (ADIN) (P < 0.01) while samples from Sefophe had least ADF and ADIN concentrations. In vitro true dry matter digestibility (IVTDMD) tended (P = 0.06) to be high in samples from Maunatlala than those from Moreomabele and Sefophe. No site difference (P > 0.05) was observed on the rest of the variables. Degutted samples had high crude protein (CP), ADF and IVTDMD (P < 0.05) but lower (P < 0.001) concentrations of ash, acid detergent lignin (ADL) and condensed tannins. Acid detergent insoluble nitrogen was significantly higher (P < 0.001) in degutted than whole samples. Salting did not (P > 0.05) change concentrations of all but ADF which tended (P = 0.09) to be high in salted samples. Samples which were degutted and salted had higher (P < 0.01) ADF and ADIN than degutted and salted or those left whole and salted or left unsalted. Leaving samples as whole diluted the concentration of CP but increased the fibre components and condensed tannins content. However, mopane worm destined for livestock feeding may be left whole and salt added.

The establishment, composition and severity of infection of gastro-intestinal parasites and their impact on productivity of Tswana kids in southern Botswana.

The presence of gastro-intestinal parasites in Tswana kids (n = 7) aged 1-3 weeks was studied for a period of 6 months at the Botswana College of Agriculture. The aims of this study were to find the time when they first contracted internal parasite infections, as well as to determine the severity of the infections and also its relation to production indicators (body mass and packed cell volume) of the kids as they grew older. The results indicate that they contracted coccidial and roundworm infections at approximately one month of age or immediately thereafter. The most prevalent internal parasite was coccidia, which occurred throughout the study period followed by roundworms and the least was the tapeworm, Moniezia expansa. Generally, the infection levels of all internal parasites were lower than the critical mean log (faecal oocyst/egg count + 1) of 3.3 inferred to cause reduced production in small stock. The correlation coefficients were all positive; 0.4-0.9 for individual internal parasites and production indicators, indicating that these internal parasites did not have any adverse effects on production. It was concluded that there was no need to treat kids of this age group for internal parasites.

The prevalence of internal and external parasites in pigs of different ages and sexes in Southeast District, Botswana.

Botswana imports most pig-based products from neighbouring countries. Pig farming is limited by, among other things, the negative effect of parasites and diseases on production. The object of this study was to determine the prevalence of ecto- and endoparasites in pigs of different ages and sexes in the Southeast District of Botswana. Thirty-nine pigs were sampled for endoparasites and 19 for ectoparasites during a period of 2 1/2 months. Of all the pigs sampled, 54,55% were infected with Ascaris suum, 20,45% with Trichostrongylus spp. and 6,82% with Trichuris suis. Ascaris suum was found to be the most common endoparasite infesting both mature, i.e. 12 months and older, and young, i.e. less than 12 months old, pigs. Although not significantly different (P > 0,05), the prevalence of this parasite species was slightly higher (68,42% with an average of 1,023 +/- 545 eggs per gram (EPG) of faeces per pig) in mature than in young pigs (55% with an of average 1,500 +/- 846 EPG of faeces per pig). The prevalence of Trichostrongylus spp. was lower in mature (5,26% with 20 +/- 14 EPG of faeces per pig) than in young pigs (25% with 22 +/- 9 EPG of faeces per pig). The prevalence of T. suis was also lower in mature (0% infection) than in young pigs (15% with 9 +/- 4 EPG of faeces per pig). The prevalence of the three endoparasite species was not significantly different between the sexes A. suum (1,020 +/- 883 v. 1,503 +/- 522 EPG of faeces per pig), Trichostrongylus spp. (24 +/- 14 v. 18 +/- 8 EPG of faeces per pig) and T. suis (11 +/- 6 v. 2 +/- 4 EPG of faeces per pig) for male and female pigs respectively. Sarcoptes scabiei was the only ectoparasite identified on the pigs sampled for external parasites. It infested 40% of all pigs but the infestation on young pigs (70%) was higher than on the mature ones (33,33%). Since the infection of internal and external parasites was similar in young and old pigs of both sexes, controlling parasites is of great importance since these generally lead to reduced production and are also of public health concern. It is recommended that a further study be carried out to investigate the effect of internal and external parasites on productivity.

The impact of traditional management on seasonal internal parasite burdens and productivity of indigenous Tswana goats in southern Botswana.

Data collected monthly over a period of two years were live weight, packed cell volume (PCV), nematode faecal egg counts (FECs) and coccidial oocyst counts from faecal analyses for 100 mixed age (3-7 years) indigenous Tswana does. The aims of this experiment were to determine seasonal FECs and coccidial oocysts in these goats and quantify the relationships of these burdens to liveweight and PCV. FECs significantly (P < 0.05) varied with season, with the warmer seasons viz spring, summer and autumn having higher log (x + 1) parasite burdens than the cooler winter, while seasonal trends for coccidial oocysts were not obvious. PCV was also significantly (P < 0.05) lower in the warmer seasons than winter. FECs and coccidial oocysts in all seasons were less than the mean log (x + 1) of 3.3 inferred to reduce production in small stock. Correlation coefficients were strongly negative: -0.95 for FECs and liveweight and -0.84 for FECS and PCV, indicating that these worms had a negative impact on productivity. A further study should be conducted to quantify the effects of controlling these parasites during the warm seasons on productivity.

Phenotypic characterization of indigenous Tswana goats and sheep breeds in Botswana: continuous traits.

The majority of Tswana sheep and goats in Botswana are indigenous. These animals provide income, employment and food security to the resource-poor farmers. Limited characterization of these species has been done, resulting in poor efforts to fully exploit and conserve them. The objective of this study was to phenotyically characterize indigenous sheep and goats countrywide. Measurements were collected from 2783 goats and 1282 sheep kept by traditional farmers, covering nearly all the districts of Botswana. In each district a total of 15 farmers with sheep and goats were selected randomly and records were taken on 4-12 animals per farm, depending on average district flock size. Traits recorded for each animal were body length, body weight, ear length, heart girth, height at withers, hip width, neck length, rump height, shoulder width, tail length (goats only) and horn length. Age (estimated from dentition) and sex of the animals were also recorded and vegetation type was noted. The data were analysed using the general linear model procedure in Statistical Analysis System. Prior to analyses, a main effects model of sex, age and vegetation type was fitted. Later, two types of analyses were done: (i) within a vegetation type fitting sex and age and their interaction, and (ii) within sex fitting age and vegetation type and their interaction. Least-squares means were separated using Student's t-test. Sex, age and vegetation significantly (p<0.05) affected the magnitude of traits. Phenotypic body measurements of castrates were generally higher than in both females and entire males, which were similar. The body measurements of younger animals were less than those of older age groups since the former were still growing compared to the latter. Different vegetation types promoted different body measurements, which should be expected due to differences in nutrient supply from different vegetation types. The indigenous breeds of sheep and goats can be classified as medium-size breeds. The breeds should be conserved since they are well suited to the harsh environment of Botswana where drought and livestock diseases are ever present. Efforts should be undertaken to characterize them genetically and increase their productivity.