Genetic parameters, productivity indices and breeding plans for designing community-based goat breeding programs in Ethiopia

The overall objectives of this dissertation were to improve access to improved/selected bucks by farmers of the research sites and to contribute to their food security and income improvements. The specific objectives were: 1) to present reliable genetic parameter estimates based on meta-analysis of literature reports; 2) to evaluate production and productivity of three indigenous goat breeds in Ethiopia namely Abergelle (AB), Central Highland (CH) and Woyto-Guji (WG) and have bench mark production and productivity estimates for the ongoing Community Based Breeding Programs (CBBPs) in Ethiopia; 3) to evaluate alternative breeding scenarios in the CBBP of the three goat breeds including dam-side selection, genomic selection and two-tier breeding programs; and 4) to assess the need for recording birth weight in CBBP of small ruminants. This dissertation was based on four articles/manuscripts. Accordingly, in article 1, unweighted and weighted average genetic parameters including direct heritability (ha 2 ), maternal heritability (hm 2 ), ratio of common environmental variances (c2 ), repeatability (R), phenotypic (rp) and genetic (rg) correlations for growth, reproduction and milk production traits in goats were presented. Unweighted averages across publications were obtained directly. For the calculation of weighted average ha 2 , hm 2 , c 2 and R, the inverse of their variances were used. Weighted average rp and rg were transformed to an approximate normal scale using Fisher’s Z transformation and then transformed back to correlations. Weighted average ha 2 for growth, reproduction and milk production traits ranged from 0.03 to 0.45, 0.00 to 0.17 and 0.15 to 0.22, respectively. Weighted averages rp and rg correlations among growth traits ranged from -0.06 to 0.84 and 0.01 to 0.98, respectively. It seemed that weighted average ha 2 , hm 2 , c 2 , R, and rg are more reliable for two reasons: weighted estimates were more conservative than values based on relatively higher number of records and the absence of significant effects of the tested fixed factors on some parameter estimates. Papers II-VI were based on data generated from the three indigenous goat breeds, in two villages for each. Production parameters including three months weight (3mw, kg), kidding interval (KI, days) and litter size at birth (LSB); and productivity indices including live weight production per parturition (kg) (index I), index I per postpartum weight (ppw) (Index II) and overall productivity (index III) were analyzed in manuscript II. Fixed effects of villages, year, season, type, sex, and parity of kids’ birth, flock size and ppw were investigated on the parameters, except for index III. The overall means of 3mw (kg) were 7.44, 10.96 and 9.38 for AB, CH and WG goat breeds, respectively. The overall means of KI were 362, 268 and 309 days for AB, CH and WG goat breeds, respectively. The overall means of LSB for AB, CH and WG goat breeds were 1.03, 1.40 and 1.09, respectively. Overall means of index I and index II were 16.66 kg and 0.50, respectively. xii Index III ranged from 0.27 to 0.53. In general, CH goat breed was found to be the most productive using the three indices. In manuscript III, application of dam-side (SN2) and genomic selection (SN3) onto the current breeding practice, where only male side selection is practiced, (SN1) and expansion of SN1 to a two tiers programs (SN4) were evaluated for three indigenous goat breeds to determine the optimal scenario(s). Due to significant distances between CH Gonder site and CH Ambo site, separate breeding plans were optimized for the CH goat breeds. The predicted annual genetic gain (PAGG) in six month weight (6mw, kg) ranged from 0.308 to 0.467 (CH Gonder site), 0.209 to 0.311(CH Ambo site), 0.188 to 0.270 (WG) and 0.174 to 0.249 (AB). The PAGGs in KI for WG goats ranged from 0.167 to 0.419 from all the scenarios. The PAGG in average daily milk yield (ml) and survival to six months (SURV) (%) for AB ranged from 0.617 to 0.970 and 0.008 to 0.013, respectively. The PAGGs in LSB and litter size at weaning (LSW) for CH were found to be small (0.001 to 0.002). The discounted profit from SN3 was negative for all breeds. Based on the PAGGs and discounted profitability, SN2 was recommended. In article IV, the Pearson correlation "r" between birth weight (BWT) & six month weight (6MW), BWT & nine month weight (9MW), three month weight (3MW) & 6MW & 3MW & 9MW; and regression coefficients ("b") of 6MW & 9MW on BWT, 6MW & 9MW on 3MW were investigated. The "r" BWT & 6MW, BWT & 9MW, 3MW & 6MW & 3MW & 9MW ranged from 0.099 to 0.176, 0.051 to 0.163, 0.598 to 0.706 & 0.370 to 0.546, respectively. The "b" of 6MW on BWT, 9MW on BWT, 6MW on 3MW & 9MW on 3MW ranged from 0.494 to 0.999, 0.311 to 0.996, 0.706 to 0.927 and 0.415 to 0.669, respectively. In general, BWT had weak "r" with 6MW & 9MW in three indigenous goat breeds of Ethiopia. However, it seems that recording BWT in the CBBP is compulsory. Hence, it was concluded that keeping BWT records under the CBBP of small ruminants has little or no significance. In summary, reliable genetic parameter estimates are presented for genetic improvements in goats. Production parameters and productivity indices presented here could be used as reliable benchmark for the anticipated CBBPs. The productivity indices could also be used to compare productivity efficiencies among different goat breeds. Planning dam-side selection could be considered together with sire side selection. Recording of BWT could be avoided in CBBPs to contribute to reduced breeding costs

Simulation of Alternative Plans for Community Based Goat Breeding Program in Arid, Semi-Arid and Mixed Production Systems in Ethiopia

On station small ruminant researches in Ethiopia were ineffective due to various factors. As alternative, community based breeding program (CBBP) has emerged. In the current CBBPs, sire side selection only (SN1) is practiced. The objective of the present work was to compare SN1 by simulating alternative breeding scenarios for Abergelle (AB), Centeral Highland (CH) and Woyto-Guji (WG) goat breeds in Ethiopia. Three scenarios including selection on dam side (SN2) in addition to SN1, application of genomic selection (SN3) onto SN1 and use of sires from SN1 for mating in additional flocks (SN4) were simulated and compared with SN1 based on the predicted annual genetic gain (PAGG) and discounted profits. The breeding objective traits or selection criteria were six month weight (6mw, kg) for all breeds, average daily milk yield (ADM, kg) and survival to six month of age (SURV) for AB, litter size at birth (LSB) for CH and WG, litter size at weaning (LSW) for CH and kidding interval (KI, days) for WG. ZPLAN+ software was used for the simulation. The PAGG for 6mw (kg) ranged from 0.087 (SN4) to 0.25 (SN3) for AB where it ranged from 0.47 (SN4) to 0.97 (SN3) for ADM (kg) for same breed. PAGG in 6mw (kg) ranging from 0.13 (SN4) to 0.47 (SN3) and from 0.20 (SN4) to 0.31 (SN3) for CH Gonder and Ambo sites, respectively were simulated whereas this parameter ranged from 0.10 (SN4) to 0.27 (SN3) for WG. The alternative breeding scenarios to SN1 resulted in better PAGGs, especially for 6mw in three of the goat breeds and for ADM in AB. Based on the PAGGs and profitability, we recommend SN2 over SN1. However, SN4 could also be applied, compared to SN1, in view of suitability of addressing emerging demands

Participatory definition of trait preferences for designing village breeding schemes for goats in harsh environments of Ethiopia

There is critical need to improve productivity of indigenous goat breeds in order to sustain supply of food and income to communities living in harsher areas that are coming to relay more and more on the drought tolerant commodity; goats, due to changing climate. To this end, a community-based goat breeding project is being implemented in 5 zones of Ethiopia by ILRI and its partners. Designing of the breeding programs proceeded phenotypic and molecular characterization of the indigenous Ethiopian goat breeds. The characterization studies revealed that ample genetic diversity exists between and within the indigenous goat breeds pointing hug potential to tap for improving productivity amid a changing climate. Participatory definition of trait preferences was undertaken to pave the way for deriving economic weights of traits to develop selection indices

Field Attractants for Pachnoda interrupta Selected by Means of GC-EAD and Single Sensillum Screening

The sorghum chafer, Pachnoda interrupta Olivier (Coleoptera: Scarabaeidae: Cetoniinae), is a key pest on sorghum, Sorghum bicolor (L.) Moench (Poaceae), in Ethiopia. At present there is a lack of efficient control methods. Trapping shows promise for reduction of the pest population, but would benefit from the development of attractive lures. To find attractants that could be used for control of P. interrupta, either by mass trapping or by monitoring as part of integrated pest management, we screened headspace collections of sorghum and the highly attractive weed Abutilon figarianum Webb (Malvaceae) for antennal activity using gas chromatograph-coupled electroantennographic detection (GC-EAD). Compounds active in GC-EAD were identified by combined gas chromatography and mass spectrometry (GC-MS). Field trapping suggested that attraction is governed by a few influential compounds, rather than specific odor blends. Synthetic sorghum and abutilon odor blends were attractive, but neither blend outperformed the previously tested attractants eugenol and methyl salicylate, of which the latter also was part of the abutilon blend. The strong influence of single compounds led us to search for novel attractive compounds, and to investigate the role of individual olfactory receptor neurons (ORNs) in the perception of kairomones. We screened the response characteristics of ORNs to 82 putative kairomones in single sensillum recordings (SSR), and found a number of key ligand candidates for specific classes of ORNs. Out of these key ligand candidates, six previously untested compounds were selected for field trapping trials: anethole, benzaldehyde, racemic 2,3-butanediol, isoamyl alcohol, methyl benzoate and methyl octanoate. The compounds were selected on the basis that they activated different classes of ORNs, thus allowing us to test potential kairomones that activate large non-overlapping populations of the peripheral olfactory system, while avoiding redundant multiple activations of the same ORN type. Field trapping results revealed that racemic 2,3-butanediol is a powerful novel attractant for P. interrupta

Designing community based breeding strategies for indigenous sheep breeds of smallholders in Ethiopia: The case of Horro sheep

A presentation prepared for the ICARDA-ILRI-BOKU project workshop on Designing community-based breeding strategies for indigenous sheep breeds of smallholders in Ethiopia, Addis Ababa, October 29, 2010

Extractives of Millettia ferruginea, Tephrosia vogellii and tephrosia pentaphylla against the bean bruchid, Zabrotes subfaciatus Ethiopain head cabbage field

No Abstract. SINET Vol. 30 (1) 2007: pp. 49-5