National forest inventory (NFI) is an efficient way to monitor forest resources, including increment, mortality, and harvest rate. It provides accurate statistical information about land use data, land use change and biomass stock change and enables to tie the specific increment, mortality and harvest data to defined land use category, dominant tree species, site types etc. Recently there have been introduced changes in land use calculation method using NFI data in Latvia. New calculation method takes into account present land use data and land use data from two previous cycles considerably reducing uncertainty of the estimates and takes into account possible land management practices which may alter the land use category in long-term, also usage of auxiliary data has been introduced to increase accuracy of determination of final land-use category. Changes in land use calculation method directly affects distribution of data on increment, morality and harvests between land use categories. The aim of the study is to determine increment, mortality and harvest rate in Latvia between the first and third NFI cycle (2004-2018) using updated land use data and to compare obtained result with data from the most recent greenhouse gas (GHG) inventory report.

Soil compaction is the compression of soil particles in a lower volume as a consequence of the reduction of the spaces existing among the particles themselves. This phenomenon is caused by natural forces and, above all, human ones. In order to estimate the field damages that can be caused by the traffic of agricultural machines, the load and the mean pressure applied by the tyres onto the soil can be measured. The research aim is to determine the pressure applied by each considered tractor onto the soil, in order to evaluate the effect of the traffic of tractors onto the soil itself. A total of 783 wheeled tractors manufactured and marketed in the last 35 years (1979-2014) were investigated. Data like construction year, manufacturer, model, power, total weight, weight (load) on the front and rear axle, wheelbase, front and rear type of tyres, as well as the tyre specifications, were collected. The mean pressure applied by each tractor onto the soil was computed by dividing the load applied on each tyre by its contact area. In order to reduce the pressure applied by agricultural machines onto the soil, the vehicle mass and, therefore weight, has to be reduced, or the tyre contact area on the soil has to be increased. Farmers can easily increase the tyre contact area, by decreasing the tyre inflation pressure or increasing the tyre width, i.e. mounting tyres having a larger section width, or Terra Tyres, or twin-tyres. Over the last 40 years: the mean power of mechanical four wheel drive (MFWD) tractors and four wheel drive (4WD) (isodiametric tyres) tractors increased, while that of two wheel drive (2WD) tractors remained constant; the power and the total weight increased, while the weight-power ratio decreased. Practically the reduction of the mean pressure on the soil resulted rather limited, meaning that tractor manufacturers have not bore in mind soil compaction.

Human living conditions are the opportunity to meet his everyday needs in the field of housing, trade, gastronomy, living services, health care, education, culture, leisure. In order to offer a new perspective on living conditions, we have linked them to rural social infrastructure. The purpose of the article is to present of the ways of defining the concept of living conditions indicated in the literature. To achieve the main goal, the following research tasks were formulated: (1) to indicate of similarities between definitions and different elements (2) propose a new approach to defining living conditions (from a local point of view, for rural areas). These questions guide our research work in order to gain a better understanding about how living conditions in rural areas develop. The main research methods were used: analysis and generalization of scientific literature and documents, abstraction method, logical and systematical reasoning, graphic presentation of comparison, abstracts and other methods. The research results disclosed that the living conditions could be highly affected by other spheres of life; highly diverse requires considering the subjective perceptions and assessments of the people who live and work in these rural area. A new approach to defining living conditions in rural areas is to relate living conditions to the social infrastructure.

This paper analyses and compares regional food systems in Latvia and Lithuania from the perspective of sustainable food security and poses three questions: (i) what are the general food system characteristics and drivers of change in Latvia and Lithuania? (ii) how are the regional food systems constructed and performing? (iii) what are the conditions and pathways for regional food systems to become more sustainable?  The paper examines in-depth the food systems in two regions – Pierīga region in Latvia and Vilnius region in Lithuania. The research is carried out within the framework of the EU projects TRANSMANGO and SALSA, and the Latvian Council of Sciences project SINFO. We find that food chain concentration and the interests of big food industries and retailers drive food systems in Latvia and Lithuania while civic and consumer-driven initiatives are becoming more important in stimulating a transition towards sustainable diets. The regional food systems are a complex intertwinement between the agro-industrial, proximity, domestic, and ecological subsystems. The pathways towards more sustainable regional food systems are difficult to negotiate and enforce as they require collaboration among various stakeholders who have different agendas. The long-term prospects of the regional food systems in terms of social and economic sustainability cannot be viewed in isolation from the demographic trends in the region, the steady depopulation in rural areas and efforts in strengthening urban-rural synergies.

peer reviewed | The Algerian agricultural sector faces the challenge to meet the food needs of its population despite low agricultural capacity, resulting in increasing pressure on natural resources. This paper aims to inventory the greenhouse gas (GHG) emissions related to livestock sector in the rural area of Chemini (province of Bejaia), taking into account the emissions due to enteric fermentation, in the form of methane, and manure management, in the form of methane and nitrous oxide. Emissions intensity, expressed in CO2- equivalents (CO2-eq) per kg of edible protein, was included in the study. Ruminants contribute to 94% of livestock GHG emissions and to 53% of protein production, with a large share due to cattle. The main part of emissions is related to enteric fermentation. High-producing cattle present the lowest emission intensity of the ruminant category with 24 kg CO2-eq per kg protein. Chickens produce 2.7% of livestock related emissions but provide 47% of animal protein. It results in low emission intensities whereas important difference is noticed between backyard and industrialized systems (around 21 versus 1 kg CO2-eq per kg protein, respectively). Improvement of animal performance should contribute to mitigate the environmental impact of livestock production in Algeria.

peer reviewed | The pig sector annually contributes about 78 % of the total meat production in Vietnam. The government of Vietnam has implemented numerous policies to promote the development of the pig industry. It strongly emphasizes the production with little attention paid to marketing. Bac Giang is one of the provinces with the highest pig population in Vietnam. Pig production contributes up to 52% of the gross output of the livestock sector of the province. One of emerging problems is the majority of pig farmers are limited in market power and there is low income from pig production. This study aimed to analyse the pig value chain in Bac Giang province, identify main factors affecting farmers‟ market power and income in the chain, and propose relevant policy implications to enhance farmers‟ market power and income. It was found that pig collectors and pork retailers are the dominant players in the chain in terms of their strong influence on prices due to their coordination role in directing supply of pigs and carcass to market. Numerous factors affecting farmer‟s market power and income are weak collective action of farmers in production, lack of collective marketing, volatility of pig price, lack of formal contract farming, consumers‟ food safety concern, high price of feed and animal disease. Enhancing farmers‟ market power depends on farmers and public authority‟s involvement in the various strategies of implementation. Some policy implications focus on the improvement of farmer collective action and government actions related to supporting farmer collective action.

peer reviewed | Un dosage sérologique des glycoprotéines associées à la gestation chez les caprins (caPAG), par la technique ELISA "sandwich" a été mis au point pour le diagnostic précoce de la gestation chez la chèvre naine de Guinée. Des anticorps anti-caPAG produits chez les lapins ont été biotinylés et titrés pour permettre ce dosage dans le sérum de chèvres. Des échantillons de sang ont été collectés tous les 7 jours chez 6 chèvres après induction et synchronisation des chaleurs puis saillie pour doser la caPAG sérique. Les densités optiques ont été lues à 492 nm sur un lecteur automatique ELISA pour établie le profil de la caPAG. Le taux de caPAG augmente rapidement pendant le premier tiers de gestation pour atteindre un pic (117 ng/ml) vers le 91e jour puis baisse pour atteindre environ 50 ng/ml le 121ème jour et reste plus ou moins stable jusqu’à la parturition où il chute progressivement pour atteindre environ 12,5 ng/ml trois semaines après. Cependant ce taux reste encore élevé dans la circulation maternelle 3 semaines après la parturition. La PAG caprine est détectable dans le sérum par cette technique à partir du 28ème jour de gestation avec une sensibilité de 100 %. Le 21ème jour, la sensibilité est faible (66,7 %). Ce test offre donc une alternative pratique au laboratoire, précoce et fiable pour le diagnostic de la gestation à partir du jour 28 après insémination chez la chèvre naine de Guinée.

peer reviewed | Hays of graminaceous species (I. cylindrica and S. palidefusca) of low quality (30g/kg dry matter (DM) Crude Protein (CP) was offered to 16 goats (8 males, 8 females), alone or with one of three tropical leguminous plants (153g/kg, 104g/kg and 305,6g/kg DM respectively). The supplementation increased total DM, energy and CP intakes and consequently allowed the weight of the goats to increase. The fodder of L. leucocephala gave the best results, while that of S. guianensis gave the lowest. Fodder of A. rhomboideus is a potential nitrogen-source supplement for poor fodder in the dry season for ruminants.

peer reviewed | Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations models such as Wood seem to be appropriate to provide persistency estimates under biological viewpoints. The aim of this study was to fit the Wood lactation model as well as to calculate and evaluate LP as selection criteria in dairy goat breeding programs through genetic parameters estimates. A total of 23,265 first lactation test day milk yield observations from 900 animals were used. The Wood random regression model was primarily fitted to estimate the lactation curve parameters (a, b and c), and then LP and total milk yield (TMY). Posteriorly, a multi-trait animal model was fitted considering simultaneously LP and TMY. The heritability estimates were 0.31 and 0.04 for TMY and LP, respectively. Based on the low LP heritability, selection based only on this trait might be inefficient. In conclusion, the results of this study suggests that selecting for high milk yields might result in high persistency since the genetic correlation between LP and TMY was moderate (0.39).

International audience | This paper deals with designing a cheap and easy-to-attain method to replace weighing for estimating the body mass of goats. Several models on the relationship of heart girth (HG) to live weight (LW) were evaluated using Creole of Guadeloupe goats (376 males and 258 growing females). The best fit was obtained with a Gompertz model: LW = 155 * exp(-7.91 * exp(-0.0215 * HG)), which provided an adjusted R² = 0.98 and a 95% confidence interval of the prediction values below 5% within most of the LW range. The LW of breeding goats (420) was fitted by the following quadratic model taking into account the HG and paunch girth (PG): LW = -28.1 + 0.539 * HG + 0.00221 * PG², which provided an adjusted R² = 0.95 and a 95% confidence interval of the prediction values below 1% within most of the LW range. The first model allows a tape measure graduated in kg to be used on goats except breeding females. The second model allows the building of an abacus to provide the estimated LWs of breeding goats from the HG and PG values. Further correction might be achieved by adding the goat body condition score. Such cheap tools should be very useful for goat farmers, most of whom lack reliable weighing devices.