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1.
J Dairy Sci ; 102(6): 5266-5278, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30954253

RESUMO

Efforts to improve dairy production in smallholder farming systems of East Africa over the past decade have had limited impact because of the lack of records on performance to guide targeted breeding programs. Estimates of genetic parameters in these systems are lacking. Using data generated through a project ("Germplasm for Dairy Development in East Africa") in Kenya and a genomic relationship matrix from genotypic records, we examined the potential impact of different models handling contemporary groups or herd effects on estimates of genetic parameters using a fixed regression model (FRM) for test-day (TD) milk yields, and the covariance structure for TD milk yield at various stages of lactation for animals using a random regression model (RRM). Models in which herd groups were defined using production levels derived from the data fitted the data better than those in which herds were grouped depending on management practices or were random. Lactation curves obtained for animals under different production categories did not display the typical peak yield characteristic of improved dairy systems in developed countries. Heritability estimates for TD milk yields using the FRM varied greatly with the definition of contemporary herd groups, ranging from 0.05 ± 0.03 to 0.27 ± 0.05 (mean ± standard error). The analysis using the RRM fitted the data better than the FRM. The heritability estimates for specific TD yields obtained by the RRM were higher than those obtained by the FRM. Genetic correlations between TD yields were high and positive for measures within short consecutive intervals but decreased as the intervals between TD increased beyond 60 d and became negative with intervals of more than 5 mo. The magnitude of the genetic correlation estimates among TD records indicates that using TD milk records beyond a 60-d interval as repeated measures of the same trait for genetic evaluation of animals on smallholder farms would not be optimal. Although each individual smallholder farmer retains only a few animals, using the genomic relationship between animals to link the large number of farmers operating under specified environments provides a sufficiently large herd-group for which a breeding program could be developed.


Assuntos
Bovinos/genética , Fazendas/economia , Leite/química , África Oriental , Animais , Cruzamento , Feminino , Genômica , Quênia , Lactação/genética , Fenótipo
2.
J Environ Manage ; 200: 423-433, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28614763

RESUMO

Major end users of Digital Soil Mapping (DSM) such as policy makers and agricultural extension workers are faced with choosing the appropriate remote sensing data. The objective of this research is to analyze the spatial resolution effects of different remote sensing images on soil prediction models in two smallholder farms in Southern India called Kothapally (Telangana State), and Masuti (Karnataka State), and provide empirical guidelines to choose the appropriate remote sensing images in DSM. Bayesian kriging (BK) was utilized to characterize the spatial pattern of exchangeable potassium (Kex) in the topsoil (0-15 cm) at different spatial resolutions by incorporating spectral indices from Landsat 8 (30 m), RapidEye (5 m), and WorldView-2/GeoEye-1/Pleiades-1A images (2 m). Some spectral indices such as band reflectances, band ratios, Crust Index and Atmospherically Resistant Vegetation Index from multiple images showed relatively strong correlations with soil Kex in two study areas. The research also suggested that fine spatial resolution WorldView-2/GeoEye-1/Pleiades-1A-based and RapidEye-based soil prediction models would not necessarily have higher prediction performance than coarse spatial resolution Landsat 8-based soil prediction models. The end users of DSM in smallholder farm settings need select the appropriate spectral indices and consider different factors such as the spatial resolution, band width, spectral resolution, temporal frequency, cost, and processing time of different remote sensing images. Overall, remote sensing-based Digital Soil Mapping has potential to be promoted to smallholder farm settings all over the world and help smallholder farmers implement sustainable and field-specific soil nutrient management scheme.


Assuntos
Fazendas , Potássio , Tecnologia de Sensoriamento Remoto , Teorema de Bayes , Humanos , Índia , Solo
3.
Heliyon ; 10(2): e24723, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304794

RESUMO

Effective decision-making requires the evaluation of several criteria rather than a single, preferred criterion. The best decision options (alternatives) are recommended to decision-makers when a multi-criteria decision problem is addressed. This study develops a multi-criteria selection method for the assessment of small-scale anaerobic digester technology by combining two existing methods. The Simple Multi-Attribute Rating Technique (SMART) and the Analytical Hierarchy Process (AHP) approaches of multiple-criteria decision analysis were used as a decision support tool, and the preferred anaerobic digester technology was selected from a list of eleven potential small-scale digester technologies used in low to middle-income countries. These techniques were applied under two scenarios for a case study in the South African smallholder farmers. Scenario 1 involves a subsistence smallholder farming context, while scenario 2 involves a commercially oriented smallholder farming context. The overall results revealed that the DIY Biobag and Puxin digester design models achieved 82.1 and 73.7 % preference in comparison to other digester technologies for scenarios 1 and 2, respectively. The Biobag digester technology achieved the highest ranking, which is consistent with the significant cost advantage and technical characteristics of the technology. However, for those households with sufficient access to funds for the initial expenditure, the method identifies the Puxin digester as the most appropriate alternative, excluding cases where underground construction is not possible. The AGAMA BiogasPro digester was ranked in the second position in both scenarios. A sensitivity analysis was conducted to determine the effect of changes in the assessment criteria weights and found the selected alternatives stable and robust. Finally, it can be concluded that the developed technology selection model contributed a knowledge-based framework to be used in various situations by different decision-makers, thereby providing a method applicable to particular local conditions to identify the most suitable technology choices.

4.
Prev Vet Med ; 212: 105833, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36693297

RESUMO

Highly Pathogenic Avian Influenza (HPAI) H5N1 is considered endemic in most parts of Indonesia and constitutes an important risk for broiler production, especially in Western Java which has the highest poultry population in the country. Most broiler farms in Western Java are smallholder farms that operate under different business types: independent (i.e., revenues based on market price and live bird weight), price-contract (i.e., revenues based on a contract selling price and live bird weight) or makloon (i.e., revenues based on a management fee per sold bird). Many studies focus on the epidemiological impacts of HPAI at the regional level, and insights into the economic impact at the farm level are scarce, especially in the Indonesian context. Meanwhile, a single HPAI outbreak could disrupt smallholder broiler farmers' primary source of income. Therefore, this study aimed to evaluate the economic impact of HPAI outbreaks under different response scenarios (i.e., no action, stamping out, and early selling) on typical Western Java smallholder broiler farms. Furthermore, the effect of different farm business types and the existence of a sick-bird market on the economic effects of HPAI outbreaks were evaluated. We developed a dynamic stochastic bio-economic simulation model to simulate epidemiological and economic impacts of HPAI outbreaks on a typical Western Java smallholder broiler farm during one production round. Our results show that the economic consequences of HPAI outbreaks for independent and price-contract farms are considerable, ranging from, on average, 1.2-62.7 million Indonesian Rupiah (IDR) losses (€76.9 to €3919), depending on the moment of and response to infection, compared to an expected gross margin of 5.3 million IDR (€331) under normal circumstances. The economic loss for makloon farms was substantially lower than for other business types, reducing their incentive to implement biosecurity. The economic impacts were sensitive to changes in a diverse set of parameters, including disease transmission rate, detection threshold, and stamping-out compensation. The losses in a scenario with stamping out were higher than in other scenarios, especially when stamping out happened near the end of the production round. Moreover, reacting to an outbreak by selling chickens early gave the lowest economic losses, incentivizing farmers to engage in behavior with a high disease transmission risk. Therefore, the results of this study suggest that it is important to consider the economic perspective of individual farmers when designing HPAI mitigation programs. Financial incentives for farmers to control HPAI differ largely between farm business types.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Doenças das Aves Domésticas , Animais , Influenza Aviária/epidemiologia , Fazendas , Indonésia/epidemiologia , Galinhas , Surtos de Doenças/veterinária , Surtos de Doenças/prevenção & controle , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia
5.
Heliyon ; 8(1): e08755, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35071816

RESUMO

BACKGROUND AND OBJECTIVE: Diversified agricultural production is considered a means to enhance food diversity at the household level, particularly in developing countries where subsistence farming is common. Given the importance of a diversified diet for human health and the persistent malnutrition problem in Bangladesh, a pressing issue is how different crops and livestock production affect household food diversification, and this study sought to answer that question. METHODS: Using a multistage sampling procedure, data were collected from 190 small farm holder households from Hatiya (a coastal rural sub-district of Noakhali, Bangladesh). Farm production diversity (FPD) is measured using the household biodiversity index (HBI), a simple count of all crops and livestock produced on the farm. The household dietary diversity score (HDDS) is calculated, according to Food and Agriculture Organization (FAO) guidelines, by counting 12 food groups consumed by the households in the last 24 h preceding the survey. RESULTS: On average, households consumed 6.49 food groups during the reference day, according to the household biodiversity index (HBI). The generalized Poisson log-linear regression results indicated that farm production diversity had a positive association with HDDS; one group of farm production increased the household dietary diversity (HDD) by 0.084 unit [ß: 0.084, 95% CI: 0.064, 0.106; Exp (B): 1.087], an 8.7% increase in dietary diversity. Total land size, less time to reach the district market, and improved irrigation process affect dietary diversity in bivariate analysis. Farmer's reliance on production diversity reduces when the market is more accessible and improved irrigation is used for production. CONCLUSION: Smallholder farm households in Bangladesh could benefit from context-specific, food-based nutrition-sensitive agriculture policies that focus on triangulation of diversified production, greater market access, and updated agricultural technology utilization.

6.
Aust Vet J ; 98(8): 375-379, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32291747

RESUMO

OBJECTIVE: The aim of this study was to determine the relationship between milk urea nitrogen (MUN) and reproductive performance in dairy cows in western Thailand. DESIGN: All cows calving from November 2014 to April 2015 were included in the study, a total of 486 cows from 47 farms. Each cow had milk constituents and MUN tested monthly up to confirmed conception or until the 8th month after parturition. Each farm had a dietary assessment completed. Cox proportional hazard models with shared frailty were used to determine associations of conception rate. RESULTS: Cows became pregnant increasingly quickly over time, except during 100-150 days of lactation. A change in MUN from 12.5 to 13.5 mg/dL on the closet day to breeding was associated with a 5% decrease in conception. Milk protein was negatively associated with hazard of conception, whereas milk lactose and dietary protein:energy ratio had positive associations with conception rate. Breeding season was also significant; the highest conception rate was observed in cows inseminated during winter, whereas insemination during the humid rainy season resulted in the lowest conception rates. The farm random effect in the model was strongly significant. CONCLUSION: Detrimental effects of higher MUN on rate of conception were identified. The rate of conception was positively associated with protein:energy ratio in the study. Therefore, good nutritional management leading to positive energy balance should benefit conception rates.


Assuntos
Lactação , Leite/química , Animais , Bovinos , Indústria de Laticínios , Fazendas , Feminino , Nitrogênio/análise , Gravidez , Tailândia , Ureia/análise
7.
Vet World ; 11(11): 1604-1608, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30587896

RESUMO

AIM: The study was to evaluate the relationship between the first service conception (FSC) and milk urea nitrogen (MUN) in smallholder dairy farms under heat and humidity stress. MATERIALS AND METHODS: Dairy cows from 43 dairy farms giving birth between November 2014 and April 2015 (n=295) contributed to the study. All cows were sampled monthly to measure milk compositions, and we collected additional farm data from farmers through a questionnaire. The first service during the first 120 days of lactation was the outcome of interest in this study. Multivariable logistic regression determined significant associations with FSC. RESULTS: The overall FSC was 22% and the mean MUN concentration was 11.55 mg/dl. The final FSC model included MUN concentration, the season of breeding, and protein energy ratio (PE ratio) in the diet. The odds of FSC were reduced by approximately 10% for each mg/dl higher MUN on the day of the milk sample that was nearest to the artificial insemination (AI) day. The odds of FSC were nearly 3 times higher when the first insemination occurred in winter compared to summer first services. Taking into account the nutritional factors, the odds of FSC were nearly 70% higher with an increase in PE ratio of 10 g of crude protein/Mcal from the mean of 35.90 g. CONCLUSION: This study of smallholder dairy farmers in the hot and humid climate of Thailand confirmed that season, nutritional management, and MUN concentration were associated with FSC. MUN appears to be a useful indicator to monitor the effects of diet on reproductive performance from this study.

8.
Vet World ; 8(1): 88-96, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27047003

RESUMO

AIM: Cows on smallholder dairy farms (SDF) in developing countries such as Kenya typically produce volumes of milk that are well below their genetic potential. An epidemiological study was conducted to determine reasons for this low milk production, including limited use of best management practices, such as suboptimal nutritional management. METHODS: An observational cross-sectional study of 111 SDF was performed in Nyeri County, Kenya in June of 2013 determining the effect of cow factors, farmer demographics and farm management practices on the volume of milk sold per cow per year (kg milk sold/cow). In particular, the effect of feeding high protein fodder trees and other nutritional management practices were examined. RESULTS: Approximatly 38% of farmers fed fodder trees, but such feeding was not associated with volume of milk sold per cow, likely due to the low number of fodder trees per farm. Volume of milk sold per cow was positively associated with feeding dairy meal during the month prior to calving, feeding purchased hay during the past year, deworming cows every 4 or more months (as opposed to more regularly), and having dairy farming as the main source of family income. Volume of milk sold per cow was negatively associated with a household size of >5 people and feeding Napier grass at >2 meters in height during the dry season. An interaction between gender of the principal farmer and feed shortages was noted; volume of milk sold per cow was lower when female farmers experienced feed shortages whereas milk sold per cow was unaffected when male farmers experienced feed shortages. CONCLUSIONS: These demographic and management risk factors should be considered by smallholder dairy farmers and their advisors when developing strategies to improve income from milk sales and animal-source food availability for the farming families.

9.
Acta amaz ; 37(2): 187-194, jun. 2007.
Artigo em Português | LILACS | ID: lil-462046

RESUMO

Na agricultura familiar na Amazônia oriental, em particular no nordeste do Pará, são comuns os cultivos semi-perenes com pesada aplicação de agrotóxicos. Em virtude da ampla utilização desses produtos, principalmente o dimetoato, na microbacia hidrográfica do igarapé Cumaru, município de Igarapé-Açu (PA), foi avaliada a retenção dessa substância em amostras da zona não-saturada em laboratório, verificando-se também a influência do pH e dos teores de argila e de matéria orgânica nesse processo. Entre os diversos agrotóxicos utilizados na área, o dimetoato foi selecionado por apresentar maior potencial de lixiviação, segundo o índice GUS (Groundwater Ubiquity Score). Para a quantificação da retenção do dimetoato nos sedimentos da zona não-saturada foi realizado um experimento de sorção. Este último mostrou que, em termos percentuais, a sorção do dimetoato variou de 2.5 por cento a 36.2 por cento (concentração inicial 20 mg.-1) e de 6.20 por cento a 31.0 por cento (concentração inicial 10 mg.-1). Esses dados comprovam o elevado potencial de contaminação da água subterrânea por essa substância, devido, principalmente, à sua mobilidade e baixa retenção. Devido ao caráter hidrofóbico do dimetoato, que aumenta a sua afinidade com a matéria orgânica, a quantidade sorvida dessa substância se mostrou diretamente proporcional à de matéria orgânica presente nos sedimentos. O pH exerce efeito contrário a este, ou seja, quanto mais elevado o seu valor, menor é a quantidade de dimetoato sorvida. Em relação à variação do teor e ao tipo de argila, foi observado que esses fatores não influenciam na retenção do dimetoato, sendo esse resultado atribuído ao comportamento não iônico desse agrotóxico.


On smallholder farms of eastern Amazonia, in particular the northeast of the Pará state, heavy by pesticide applications at industrial half-perennial crops are very common. Due to their large use, mainly the dimethoate, in the catchment of the Cumaru stream, Igarapé-Açu county, we evaluated the retention process of this compound in samples of the non saturated zone, as well as verified the effects of soil pH and clay and organic mater contents in this process. Among the main pesticides the farmers use in this region, dimethoate was selected for this study, due to its larger leaching potential according to the GUS (Groundwater Ubiquity Score) index. A sorption experiment was carried out to evaluate the retention of the dimethoate in sediments in the non saturated zone. The experiment showed that the sorption of the dimethoate varied from 2.5 percent to 36.2 percent (initial concentration of 20 mg.l-1) and from 6.2 percent to 31.0 percent (initial concentration of 10 mg.l-1). These data demonstrate a high contamination potential of the groundwater by this compound, mainly due to its high mobility and low retention capacity. The dimethoate sorption rates were positively related to organic matter content in the sediments. On the other hand, values have an inverse relationship with the sorption rates of dimethoate, while clay content did not produce any effect on its retention.


Assuntos
Água Subterrânea , Percolação , Agroquímicos
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