| Literature DB >> 30715656 |
A R Chawala1,2,3, G Banos4,5, A Peters6, M G G Chagunda7.
Abstract
Decisions of breeding schemes in many countries in sub-Saharan Africa tend to be either government or project driven, with a focus on upgrading local breeds. However, there is scant information on the individual animal traits that smallholder farmers prefer. The aim of this study was to examine farmers' preferences of dairy cattle traits using a discrete choice experiment methodology. The study was conducted through visits to 555 randomly selected dairy farms in the sub-humid Eastern coast and temperate Southern highlands of Tanzania. Choices of animal traits were presented to farmers who were asked to evaluate choice alternatives based on attribute levels and finally select the alternative with the highest utility. The choice experiment data were analysed using a conditional logit model. Coefficients for milk yield, fertility, feed requirement, temperament and diseases resistance were overall statistically significant (p < 0.05). In order of perceived importance, farmers were willing to keep a cow with high milk yield (coefficient = 1.43 ± 0.059), good fertility (0.85 ± 0.050), easy temperament (0.76 ± 0.066), low feed requirement (- 0.56 ± 0.092) and enhanced tropical disease resistance (0.48 ± 0.048). The purchase price coefficient was negative (- 0.001 ± 0.0003), indicating that farmers would prefer improved dairy cattle at affordable prices. Farmers' preferred traits were influenced by agro-ecological zone and type of production system (extensive vs intensive). The study provides an opportunity for breeding programme designers to take farmers' preferred dairy traits into serious consideration.Entities:
Keywords: Breeding goal; Choice experiment; Dairy traits; Trait preference
Mesh:
Year: 2019 PMID: 30715656 PMCID: PMC6597596 DOI: 10.1007/s11250-018-01796-9
Source DB: PubMed Journal: Trop Anim Health Prod ISSN: 0049-4747 Impact factor: 1.559
Dairy trait and their corresponding levels used in the discrete choice experiment
| Attribute | Description | Levels definitions | A priori expectation |
|---|---|---|---|
| i High milk yield | Milk is a source of protein, employment and income for many smallholder dairy farmers. However, there is a vast variation in milk yield between genotypes and production systems. For example, as part of the Dairy Genetics East Africa (DGEA) Project, it was found that higher milk production levels were found in cows under intensive (zero gazing) compared to extensive (grazing and semi-grazing) production systems (DGEA | Two levels of milk yield of 5 and 10 l/cow/day were chosen, based on the average milk production in semi-intensive and intensive dairy production systems in Tanzania. - Level 1: 5 l/cow/day accounted for the actual milk production per cow of the majority of smallholder dairy farmers (about 90%) (DGEA - Level 2: 10 l/cow/day accounted for the top 10% of the best smallholder dairy farmers (DGEA | In general, a positive preference for higher milk yield/cow/day was expected |
| ii Good fertility | Smallholder dairy farmers are interested in cow fertility to ensure continued milk production on farm. Longer calving interval affects annual milk production and increases labour costs. The reported calving interval of improved dairy cattle in Tanzania ranges between 13 and 16 months, which is comparable to most countries in sub-Saharan Africa. | Two levels were chosen for cow fertility in smallholder dairy farms. - Level 1: one calf after every 1 to 1.25 years, considered good fertility - Level 2: 1 calf after every 2 years, considered poor fertility | In general, a positive preference for cows that produces a calf every year is expected |
| iii Animals that best convert of the commonly available feeds into milk | Daily feed requirement is important due to seasonal availability of feeds and under developed pastures on most of the farms (DGEA | Two levels were chosen for the ability of the cow to use the available feed resources - Level 1: smaller body size (low feed requirement) to produce moderate volumes of milk using locally available feed resources - Level 2: large body size (high feed requirements) to produce high volumes of milk using locally available feed resources | Current breeding strategies are based on increased milk volumes per cow. Therefore, a positive preference for cows with higher milk volumes and hence higher feed requirements was expected. |
| iv Temperament | Good temperament is used as criteria for easy handling of cows. During the focused group discussions; temperament was a prominent trait for farmers under semi-grazing systems where animals were taken for grazing or tethered in pasture plots. | Preference for temperament was assessed in two levels. - Level 1: docile cow/easy to care - Level 2: aggressive cow | In general, a positive preference for good temperament of cows was expected. |
| v Animals better adapted to the local production environment. | This attribute includes a range of climatic factors affecting cow productivity. Adaptability to temperature and diseases affects the economic performance of a cow directly through reduced veterinary costs and improved quality of products. For example, in coastal areas, adaptability to hot and humid coastal environments such as tolerance to high ambient temperatures and high humidity are essential. In the highlands and medium altitude areas, ability to cope with different disease, e.g. tick-borne diseases is important. | Two levels of adaptability to production environment were chosen based on annual disease incidences and of use of veterinary services. - Level 1: animal frequently treated for various diseases treatments (> = 4 times a year) - Level 2: animal rarely treated for various diseases (< 4 times a year) | In general, a positive preference for low incidence of veterinary service use was expected |
| i Purchase price of cow with the desired traits | The purchase price attribute was based on the current prevailing market price for dairy heifers in Tanzania. For example, as part of the DGEA project in Tanzania, it was reported that purebred animals fetched a higher price than crossbreds. The price range for improved dairy cows in Tanzania ranges between 750,000–1,200,000 TZS with an average of 850,000 TZS (DGEA | Two price levels were included based on current market prices for improved dairy cattle in Tanzania. - Level 1: 750,000 TZS—equivalent to £250. This accounted for a lower price for improved dairy cattle. - Level 2: 1,200,000—equivalent to £400. This accounted for a higher price for improved dairy cattle. | Positive preference for reduced animal price was expected |
Estimates of overall dairy preference traits for smallholder dairy farmers in Tanzania
| Coefficient ± SE | ||
|---|---|---|
| Intercept | 0.85 ± 0.159 | < 0.0001 |
| Milk yield | 1.43 ± 0.059 | < 0.0001 |
| Fertility | 0.85 ± 0.050 | < 0.0001 |
| Feed requirement | − 0.56 ± 0.092 | < 0.0001 |
| Temperament | 0.76 ± 0.066 | < 0.0001 |
| Disease resistance | 0.48 ± 0.048 | < 0.0001 |
| Price | − 0.001 ± 0.0003 | 0.0004 |
| Rho-squared | 0.30 | |
| Number of observations | 13,320 | |
| LL of the model | − 3399.21 | |
| LL of the model without predictors | − 4842.68 |
LL, log likelihood; SE, standard error
Estimates of smallholder farmers’ preference traits in two agro-ecological zones and production systems
| Southern highland zone | Eastern coastal zone | |||||||
|---|---|---|---|---|---|---|---|---|
| Intensive systems | Extensive system | Intensive systems | Extensive system | |||||
| Coefficient ± SE | Coefficient ± SE | Coefficient ± SE | Coefficient ± SE | |||||
| Intercept | 0.04 ± 0.247 | 0.85 | 1.74 ± 0.718 | 0.016 | 2.88 ± 0.343 | < 0.0001 | 0.03 ± 0.345 | 0.92 |
| Milk yield | 2.16 ± 0.088 | < 0.0001 | 0.12 ± 0.295 | 0.691 | 0.78 ± 0.126 | < 0.0001 | 1.14 ± 0.128 | < 0.0001 |
| Fertility | 0.82 ± 0.075 | < 0.0001 | 0.12 ± 0.242 | 0.627 | 0.81 ± 0.093 | < 0.0001 | 0.98 ± 0.129 | < 0.0001 |
| Feed requirement | − 0.59 ± 0.138 | < 0.0001 | − 0.04 ± 0.424 | 0.925 | − 0.59 ± 0.199 | 0.0028 | − 0.09 ± 0.205 | 0.65 |
| Temperament | 0.70 ± 0.095 | < 0.0001 | 0.12 ± 0.305 | 0.700 | 0.36 ± 0.12 | 0.0046 | 1.66 ± 0.178 | < 0.0001 |
| Disease resistance | 0.52 ± 0.077 | < 0.0001 | 0.52 ± 0.235 | 0.026 | 0.36 ± 0.092 | < 0.0001 | 0.72 ± 0.111 | < 0.0001 |
| Price | − 0.001 ± 0.0005 | 0.088 | − 0.002 ± 0.0016 | 0.270 | − 0.002 ± 0.0006 | 0.036 | − 0.001 ± 0.0008 | 0.18 |
| Rho-squared | 0.37 | 0.18 | 0.33 | 0.33 | ||||
| Number of observations | 6432 | 432 | 3744 | 2712 | ||||
| LL of the model | − 2326.86 | − 129.74 | − 910.50 | − 666.53 | ||||
| LL of the model without predictors | − 1465.04 | − 158.20 | − 1364.48 | − 993.15 | ||||
LL, Log Likelihood; SE, Standard error
Farmer marginal willingness to pay and preferences for each trait by agro-ecological zone
| Southern highland zone | Eastern coastal zone | |||||||
|---|---|---|---|---|---|---|---|---|
| 1MWTP (£) | MWTP (£) 95% CI | Coefficient ± SE | MWTP (£) | MWTP (£) 95% CI | Coefficient ± SE | |||
| Intercept | 1.17 ± 0.712 | 0.100 | 2.73 ± 0.677 | < 0.0001 | ||||
| Milk yield | 404.42 | 172.05–2358.33 | 2.01 ± 0.083 | < 0.0001 | 47.33 | 85.26–465.20 | 0.89 ± 0.087 | < 0.0001 |
| Fertility | 156.02 | 57.99–944.66 | 0.77 ± 0.071 | < 0.0001 | 147.34 | 76.93–517.02 | 0.89 ± 0.074 | < 0.0001 |
| Feed requirement | − 115.08 | (− 581.18)–(− 42.07) | − 0.57 ± 0.130 | < 0.0001 | − 71.43 | (− 187.59)–(− 31.48) | − 0.43 ± 0.138 | 0.0018 |
| Temperament | 134.93 | 44.94–826.51 | 0.67 ± 0.090 | < 0.0001 | 138.70 | 64.82–520.97 | 0.83 ± 0.100 | < 0.0001 |
| Disease resistance | 102.60 | 38.18–573.79 | 0.51 ± 0.072 | < 0.0001 | 74.64 | 40.63–226.90 | 0.45 ± 0.068 | < 0.0001 |
| Price | − 0.005 ± 0.0025 | 0.005 | − 0.006 ± 0.0023 | 0.0094 | ||||
| Rho-squared | 0.34 | 0.31 | ||||||
| Number of observations | 6864 | 6456 | ||||||
| LL of the model | − 2485.06 | − 2357.62 | ||||||
| LL of the model without predictors | − 1629.07 | − 1638.42 | ||||||
LL, log likelihood; SE, standard error; CI, confidence interval; 1MWTP, marginal willingness to pay; £, British pound sterling
Currency exchange rate: 1 British pound = 2956.04 Tanzanian shillings (31 July 2017 https://www.xe.com)