45 research outputs found

    Quantifying morphometric and adaptive characteristics of indigenous cattle genetic resources in northwest Ethiopia

    Get PDF
    Ethiopia is the gateway of livestock genetic resources to Africa and has a wide range of altitude. It is endowed with huge diverse cattle genetic resources. The aim of this research was to determine the morphometric and potentioally adaptive characteristics of cattle populations. Multi-stage purposive and random sampling methods were employed to select the study areas, households and animals. A total of 1200 adult cattle were sampled and characterized for 14 qualitative and eight morphometric variables. The comparison of marginal means, chi-square tests, canonical discriminant analysis, and clustering analysis were employed using SAS and SPSS statistical software. The sex of the animal, location and agro-ecology were fitted as fixed effects in the model and had highly significant (p 0.45) values. White with red, light red, black and dark red were the most predominant coat colour types of cattle. The maximum hit rates were recorded in Enebsie and Sinan cattle. From five extracted canonical variate, (can1 and can2) accounted 75.4% and 78.8% in the female and male cattle populations, respectively. The canonical class has separated cattle populations of Sinan from Banja at can1 and Mecha from Sinan populations at can2. The square Mahalanobis distances between sites were significant (p<0.001) and the largest distance was found between Banja and Sinan locations. Cluster analysis result classified the study populations into four major cattle groups. The cumulative analysis results showed that the cattle populations of the study area can be categorized into four breed types as Jawi Sanga, Gojjam Zenga, Banja cattle, and Sinan cattle. However, this morphology based grouping need to be confirmed by molecular data

    Management practices, reproductive performances, and production constraints of indigenous cattle in north-western parts of Ethiopia

    Get PDF
    Description of the production condition and level of performance is the first step in improving production performance. The study described the indigenous cattle reproductive performances, management practices and production limitations in north-western Ethiopia. Multistage purposive and random sampling methods were used to select the study sites/districts and households. A semi-structured questionnaire (320 interviewees), focus group discussions (12) and personal observations were used for data collection. Chi-square (χ2) test, the least squares mean and the ranking indexes were the statistical methods employed for data analysis. Livestock composition, reproductive performance and production constraints of cattle showed significant differences (p &lt; 0.001) between agro-ecological zones. Cattle were the dominant livestock species, with mean numbers of 18.3 ± 9.9, 8.1 ± 3.2 and 5.4 ± 2.5 heads in the lowland, midland and highland agro-ecological zones, respectively. The mean ages at first mating of bulls, first service of heifers, first calving and calving interval of cows were best in the highlands, while the midland agro-ecology had the worst performance. Feed shortage (Index = 0.4) and disease prevalence (Index = 0.25) were the main cattle production problems. Natural pasture was the main feed source for cattle in the study areas. The study revealed a significant effect agro-ecology on landholding, cattle management practices, species composition; cattle herd structure, reproductive performances and cattle production constraints. This implies that the socioeconomic characteristics, management-level constraints for production and performance level of the livestock stock are important for developing improvement strategies for smallholder livestock production in different agro-ecological zones.</p

    Genetic parameters of forage dry matter intake and milk produced from forage in Swedish Red and Holstein dairy cows

    Get PDF
    High-yielding dairy cows are often fed high proportions of cereal grain and pulses. For several reasons, it would be desirable to replace these feed sources with forage, which is not suitable for human consumption. Feeding large amounts of forage to dairy cows could also make dairy production more publicly acceptable in the future. In this study, we estimated genetic parameters for total dry matter intake (DMI), DMI from forage (DMIFor), energy-corrected milk (ECM), and ECM produced from forage (ECMFor). A total of 1,177 lactations from 575 cows of Swedish Red (SR) and Holstein (HOL) dairy breeds were included in the study. Mixed linear animal random regression models were used, with fixed effect of calving season and lactation week nested within parity 1 and 2+, fixed effect of calving year, and random regression coefficients for breeding value (up to linear) and permanent environmental effect (up to quadratic) of the cow. Heritability for DMI and DMIFor was generally higher for HOL than for SR in all-parity data and in later parities; however, the opposite was true for first parity. Heritability for DMI and DMIFor during the first 8 wk averaged 0.11 and 0.15, respectively, in all-parity data for the 2 breeds. Corresponding values for ECMFor and ECM were 0.21 and 0.29, respectively. In first parity, values were 0.32, 0.36, 0.28, and 0.51, respectively. The genetic correlation between DMI and DMIFor was high, above 0.83, and fairly constant across the lactation. The genetic correlation between ECMFor and ECM was close to unity in the later part of lactation for both breeds, but was around 0.8 in the early lactation for both breeds; it decreased for HOL to 0.54 in wk 17. The genetic correlations between DMI and ECMFor and between DMIFor and ECMFor were low and negative for HOL (absolute value similar to 0.2-0.3), but changed for SR from weakly positive in early lactation to negative values and back to positive toward the end of lactation. For most traits, the correlation between wk 1 and wk 8 into the lactation was very high; the lowest value was for DMI in HOL at 0.81. The genetic correlation between parities was rather high in the first part of the lactation. During the first 8 wk, the correlation was lower for HOL than for SR, except for ECM. We found that DMIFor and ECMFor showed reasonably large heritability, and future work should explore the possibility of genomic evaluations

    Breeding objectives and selection criteria of farmers keeping indigenous cattle populations in north-west Ethiopia

    Get PDF
    This study was conducted to identify farmers’ breeding objectives and trait preferences for indigenous cattle in north-west Ethiopia. Multistage purposive and random sampling techniques were used to select study districts, and smallholder farmers. The required data were collected through structured questionnaires from 320 households, personal observations, and focus group discussions. The chi-square (χ2) test, least squares mean, and ranking index were statistical methods used for data analysis. The least squares mean analysis showed a difference (p &lt; 0.001) and the mean herd size was 10.9 heads. Based on ranking index results, milk production (0.35) and draught power (0.25) were the main cattle production purpose/objectives of farmers. The chi-square (χ2) test results of mating practices showed a significant difference (p &lt; 0.001) and 63.8% of farmers used controlled mating. According to the ranking index result, large body size (0.35), colour (0.26), and good traction (0.18) were considered the most important traits in selecting a breeding bull. High milk yield (0.4), colour (0.19), large body size (0.16), and calf growth (0.13) were the preferred traits/criterias for cow selection. Prioritizing farmer trait preference and breeding objectives in this study was critical for the design and implementation of breeding programmes.</p

    Typology and characteristics of indigenous goats and production systems in different agro-ecological zones of Tanzania

    Get PDF
    Tanzania has a goat population of about 24.8 million most of which belong to the Small East African breed distributed in almost all agro-ecological zones. The different goat populations and the production system in which they are raised are not well characterized depriving animal breeders useful information in designing and running improvement and conservation programs. Therefore, the study was conducted in all agro-ecological zones in Tanzania to characterize the indigenous goats and the production system in which they are raised. Data on animals were collected from 688 randomly selected adult female goats and for production system description; 220 households were interviewed. Analysis of variance and discriminant analysis were used on quantitative data, while frequency analysis was used on qualitative data. Income generation and meat production were the primary goat rearing objectives. More than 55% of respondents grazed their animals freely in communal lands where natural pasture was the chief feed resource. Mating was mainly uncontrolled with apron and castration being used by goat keepers as mating control methods. Common diseases were contagious caprine pleural pneumonia and helminthiasis. Feed shortage, prevalence of diseases, and water scarcity were the major goat production constraints. There were morphological variations between and within these goat populations, and based on quantitative data, the goats were categorized into two groups. High twinning was observed in Ujiji and Lindi goats and low for Sukuma. The dominant coat color was plain white in Pare, Gogo, Maasai, and Tanga. Other coat color patterns were mixed black and white for Sukuma, reddish-brown for Lindi, black and reddish-brown for Ujiji, and white and reddish-brown for Pwani and Maasai. High within population variation is observed which is important as it can be used as a basis for genetic improvement through selection

    Variations in mitochondrial cytochrome b region among Ethiopian indigenous cattle populations assert Bos taurus maternal origin and historical dynamics

    Get PDF
    Objective This study was carried out to assess the haplotype diversity and population dynamics in cattle populations of Ethiopia. Methods We sequenced the complete mitochondrial cytochrome b gene of 76 animals from five indigenous and one Holstein Friesian×Barka cross bred cattle populations. Results In the sequence analysis, 18 haplotypes were generated from 18 segregating sites and the average haplotype and nucleotide diversities were 0.7540±0.043 and 0.0010±0.000, respectively. The population differentiation analysis shows a weak population structure (4.55%) among the populations studied. Majority of the variation (95.45%) is observed by within populations. The overall average pair-wise distance (F ST) was 0.049539 with the highest (F ST = 0.1245) and the lowest (F ST = 0.011) F ST distances observed between Boran and Abigar, and Sheko and Abigar from the indigenous cattle, respectively. The phylogenetic network analysis revealed that all the haplotypes detected clustered together with the Bos taurus cattle and converged to a haplogroup. No haplotype in Ethiopian cattle was observed clustered with the reference Bos indicus group. The mismatch distribution analysis indicates a single population expansion event among the cattle populations. Conclusion Overall, high haplotype variability was observed among Ethiopian cattle populations and they share a common ancestor with Bos taurus

    Whole-Genome Resequencing Reveals Selection Signatures of Abigar Cattle for Local Adaptation

    Get PDF
    Over time, indigenous cattle breeds have developed disease resistance, heat tolerance, and adaptability to harsh environments. Deciphering the genetic mechanisms underlying adaptive traits is crucial for their improvement and sustainable utilization. For the first time, we performed whole-genome sequencing to unveil the genomic diversity, population structure, and selection signatures of Abigar cattle living in a tropical environment. The population structure analysis revealed that Abigar cattle exhibit high nucleotide diversity and heterozygosity, with low runs of homozygosity and linkage disequilibrium, suggesting a genetic landscape less constrained by inbreeding and enriched by diversity. Using nucleotide diversity (Pi) and population differentiation (FST) selection scan methods, we identified 83 shared genes that are likely associated with tropical adaption. The functional annotation analysis revealed that some of these genes are potentially linked to heat tolerance (HOXC13, DNAJC18, and RXFP2), immune response (IRAK3, MZB1, and STING1), and oxidative stress response (SLC23A1). Given the wider spreading impacts of climate change on cattle production, understanding the genetic mechanisms of adaptation of local breeds becomes crucial to better respond to climate and environmental changes. In this context, our finding establishes a foundation for further research into the mechanisms underpinning cattle adaptation to tropical environments.</p

    Typology, management and smallholder farmer-preferred traits for selection of indigenous goats (Capra hisrcus) in three agro-ecological zones in the Democratic Republic of Congo

    Get PDF
    The present study aimed to assess the typology, production management, and smallholder farmer-preferred traits in selecting indigenous goats in three agro-ecological zones (AEZs) in the Democratic Republic of Congo (DR Congo). Based on a structured survey, baseline data were recorded on 320 adults and unrelated does from 202 goat farms. Hierarchical clustering on principal components revealed three clusters in the goats studied well distinguished by double and triple kidding. Prolific goats mostly clustered into cluster two and three more represented by goats of South Kivu while 82.69% of goats in Tshopo were clustered into cluster one characterized by low reproductive performances. The Canonical Discriminant Analysis revealed that the body length was an important variable both to discriminate and to classify goats from the three AEZs. Goats from Kinshasa and South Kivu were not distanced while large distance was observed between goats from Kinshasa and Tshopo (F-stat, p < 0.001). While not subjected to any good management practices, goats were considered as a source of income and saving method in smallholder farmers' households. Adaptability, resistance to disease and prolificacy were preferred traits by farmers in selecting goats. These results give the first step in the decision-making towards goat improvement in DR Congo
    corecore