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Impacts of municipal wastewater treatment plants on water quality in the Berze River basin [Latvia] Texte intégral
2017
Dambeniece-Migliniece, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Lagzdins, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Eutrophication caused by water pollution with nutrients (nitrogen (N) and phosphorus (P)) is one of the main environmental problems nowadays. Poor water quality might be caused by many natural and anthropogenic factors. The most common anthropogenic factors are water pollution caused by intensive agriculture (e. g. intensive fertilizer use, high density of livestock) and discharges from municipal waste water treatment plants (WWTP). In this study, nutrient load from WWTP to the River Berze basin in time period from the year 2005 to the year 2015 was described. In total, 23 WWTPs of the study area were analysed using descriptive statistics to calculate average values of nutrient amount and concentrations discharged to River Berze basin. From 2005 to 2015 average N and P load from WWTP to the River Berze basin have been reduced, but concentration of N and P in treated wastewater (WW) have increased. The largest WWTP of the study area – Krigeri (WWTP of city Dobele) is subject to the regulations of treated WW quality set by Republic of Latvia Cabinet Regulation No. 34. The WWTP Krigeri meets the regulations, but overall situation in the study area suggests that strict control of smaller WWTP should be made.
Afficher plus [+] Moins [-]Importance of landscape elements in perception of spatial aesthetics in residential areas Texte intégral
2017
Kusmane, A.S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ile, U., Latvia Univ. of Agriculture, Jelgava (Latvia)
Our previous research was focussed on evaluating spaces in the Soviet period housing estates in Riga according to theoretical model of spatial measurements. This model was based on assumption established ex situ that liking and perception of urban space is closely related to buildings. Namely, to the way walls of the buildings shape a setting in terms of its height, width, length. This current paper sets the goal to analyse the impact of landscape elements such as trees, benches, elevations of earth surface, playgrounds on the perception and preference of open spaces in situ. This is done to verify the hypothesis that landscape elements as well as the method of research play a role in our knowledge on how urban spaces are regarded. Semi-structured interviews in walk-along modus are used to talk to inhabitants about the ways they see and like yards and streets in three residential areas: ‘Agenskalna priedes’, ‘Kengarags’, ‘Zolitude’. The interview materials are analysed discursively. The extracted information is compared to the data previously acquired by using the model of spatial measurements. The results of interviews show that trees are the landscape elements that have the largest impact on how residents perceive the size of a space and how they like a setting. There are also other elements such as benches, playgrounds, elevations that play a role. The interview material displays deviations in preference and perception of the size of space compared to the model of spatial measurements. Yet these deviations can be adapted to the model.
Afficher plus [+] Moins [-]Effect of high pressure processing on milk coagulation properties Texte intégral
2017
Liepa, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zagorska, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
Raw milk cheeses are known to have more intense and strong flavour and different texture due to natural microbiota and enzymes. Nevertheless, there are concerns about safety of these products. For microbial inactivation heat treatment of milk is used, but it can adversely affect the flavour, taste and texture of the product. Therefore, applying non-thermal technology such as high pressure processing is attracting alternative. The aim of this study was to examine the effects of high pressure treatment of cow`s milk at a wide range of pressures (400–600 MPa) on milk rennet coagulation time, curd firmness and curd yield. Processed milk samples were subjected to enzymatic coagulation using commercial rennet to determine rennet coagulation time, yield of coagulum and curd firmness. High pressure processing insignificantly influences coagulation properties of whole milk. However, the magnitude of changes depended on applied pressure. Rennet coagulation time and curd yield were significantly different (p is less than 0.05) among the pressure treated milk samples. The higher firmness of the curd form pressurized milk than that of raw or pasteurized milk, evaluated positively. The main effects of high pressure treatment in milk appeared to involve dissociation of casein micelles from the colloidal to the soluble phase. This study suggests that high pressure treatments of milk at 500 MPa or 550 MPa for 15 min may be beneficial for improving the coagulation properties of milk. These positive effects indicated that high pressure processing may have potential for new cheese varieties development.
Afficher plus [+] Moins [-]Effect of high pressure processing on microbial load in pork Texte intégral
2017
Sazonova, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gramatina, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
Fresh meat is a highly perishable product due to its biological composition as it serves as an ideal environment for the growth and propagation of microorganisms and common food-borne pathogens. High pressure processing (HPP) is a cold pasteurization treatment to extend shelf-life while preserving the sensory and nutritional characteristics of the product. The aim of this research was to evaluate the effects of HPP on the fresh porcine Musculus longissimus lumborum microbial load and related physical properties (pH, water activity aw, and moisture content). Vacuum packed meat samples were treated at 50, 100, 200, 300, 400, and 500 MPa for 1, 5, and 15 min in a high-pressure processor ISO-Lab S-FL-100-250-09-W (Stansted Fluid Power Ltd., UK). Pressure treatment above 300 MPa resulted in a significant (p is less than 0.05) decrease of total plate count. However, the studied pressurizing time had no significant effect on microbial lethality at the same pressure applied. Other important parameters such as water activity, moisture, and pH were determined as they directly affect microorganism growth and resistance to pressure. A slight increase in pork pH was observed with increased pressure. No significant changes in water activity and moisture content were observed as a result of high pressure treatment. For future researches it would be important to evaluate the dynamics of microbial growth during storing as part of cells after pressure treatment are injured and not eliminated immediately; therefore, microbial count may further decrease during cold storage.
Afficher plus [+] Moins [-]Immunogenicity of the Newcastle disease virus vaccine La Sota, in introduced birds under intensive and extensive management conditions Texte intégral
2017
Abera, Berhanu | Lynch, Stacey E. | Duguma, Reta | Dessie, Tadelle | Bettridge, Judy M. | Wigley, Paul | Christley, Robert M.
The study was designed to evaluate the immune response of chickens among different poultry management following challenge to live La Sota vaccine and further more investigated the lower antibody response detected in traditionally managed chicken, by testing the hypothesis that veterinary intervention (treatment with anti-helminthic, antibiotics and vitamin supplements), prior to vaccination, would improve the antibody response to live NDV vaccination. Even if, a protective level of antibody (> 4 Log 2HAI) was detected in all chickens following vaccination, antibody titres were significantly higher (p < 0.05) in the intensively managed chickens Geometric Mean Titre (GMT) 85.4 when compared with the traditionally managed chickens GMT 59.3. From multivariable analysis; following a single live ND virus vaccine at the age of 21 day, chickens rearing in intensive production system were 8.6 times more likely to have high titre (128 vs 32) compared to those rearing in backyard free ranging system. The lower ND-HI titre in extensively managed chickens recorded in our study had be explained by impaired immune-competence due to immune-suppressive of concurrent infection. The study investigated the effect of concurrent parasitic and viral diseases on the immune response; as well as differences in protection among indigenous ecotype and exotic breed of chicken. The hypothesis that parasitism contributes to a poorer response to vaccination was proven (p < 0.05). Chickens that received veterinary treatment (de-wormed chickens) prior to vaccination were approximately 14 (i.e. 14.3) times more likely to have a titre of 128 when compared to titre 32 showing evidence for veterinary intervention had detectable effect on humoral response of chicken to vaccination (p< 0.05). Moreover; it was evident that HI titer differed between individual chickens and was influenced by breed types. Multivariate analysis showed that indigenous chickens were about 7 times more likely to have high HI titre (128 vs 32) compared to exotic breeds (p< 0.05). Though breeds differ genetically in their immune responsiveness to the antigen, and being protected following challenge; difference in their susceptibility to the virulent challenge virus needs to be ruled out in order to facilitate the improvement of disease-resistant traits.
Afficher plus [+] Moins [-]Body condition score, some nutritional parameters in plasma, and subsequent reproductive performance of Montbéliarde cows in Algeria Texte intégral
2017
Kalem, Ammar | Hanzen, Christian | Abdelli, A | Kaidi, Rachid
peer reviewed | The objective of this study was to investigate the relationships among body condition score (BCS) and plasma metabolite concentrations, and subsequent reproductive performance of Montbéliarde cows in Algeria. The study was conducted in two commercial dairy farms in Tizi-Ouzou area. Blood samples were collected from 50 Montbéliarde dairy cows at 2, 4, 6 and 8 weeks postpartum to measure serum non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), glucose, total cholesterol, urea nitrogen, total protein, aspartate aminotransferase (AST), alanine aminotransferase (ALT), γ-glutamyltransferase (γGT), calcium, magnesium, potassium, phosphorus, sodium, and progesterone. Body condition score (BCS) was assessed at calving and at each time when blood samples were taken. Resumption of postpartum cyclicity was evaluated by progesterone concentrations (≥1 ng/mL) at 4, 6, and 8 weeks postpartum. Increased BHBA, NEFA and glucose concentrations were associated with a lower probability of ovarian activity resumption (ROA) and pregnancy at first insemination (P/1-AI). However, concentrations of plasma cholesterol, AST, ALT, TG and total protein were positively associated with ROA. In addition, increased BHBA and sodium were associated with increased of time to conception. Moreover, decreased Mg concentrations were associated with increasing of time from calving to first insemination. No significant effect was seen between BCS at calving and BCS loss on P/1-AI. So balanced nutrition and reproduction management can ameliorate reproductive performance.
Afficher plus [+] Moins [-]Développement d'un outil cartographique pour la gestion des ressources pastorales par une approche combinée de télédétection et de modélisation Texte intégral
2017
Razafinarivo, Tsirinirina Donnah | Rahetlah, Volatsara Baholy | Rakotozandriny, Jean de Neupomuscène | Salgado, Paulo | Degenne, Pascal
La croissance démographique et l'urbanisation engendrent une augmentation de la demande en produits d'origine animale alors que la disponibilité en ressources fourragères se réduit. Un système d'évaluation et de suivi pour estimer la quantité de biomasses fourragères disponibles est indispensable. Ainsi, une approche combinée de télédétection, modélisation et programmation informatique a été utilisée pour créer un tel outil cartographique. Pour cela, des mesures de données agronomiques sur le terrain sont couplées avec des données d'imagerie satellitaire pour élaborer des modèles de prédiction. Les modèles obtenus sont ensuite utilisés sur plusieurs images satellites archivées pour retracer le profil de disponibilité temporel des différentes espèces fourragères via la juxtaposition de 4 066 extraits d'indices de végétation (NDVI) obtenus à Madagascar. À chaque acquisition d'image satellite, les paramètres de l'équation du profil temporel sont modifiés, pour calculer de nouveaux rendements de biomasse, par l'assimilation dans les modèles de prédiction des données obtenues via l'imagerie satellite. L'état d'exploitation de la biomasse et la capacité de charge animale des différentes parcelles de pâturages, prédits par les modèles, constituent des données d'aide à la décision pour une gestion optimale de l'usage des parcelles. Les modèles sont ensuite implémentés et intégrés à une interface cartographique et de pilotage à partir d'une page Web. Ainsi, il est possible de dessiner une parcelle sur fond d'image satellite, puis de calculer les différents indicateurs pour cette parcelle. À travers la même interface Web, ces modèles peuvent aussi être utilisés comme outils de prospective permettant d'estimer la production fourragère sur plusieurs semaines après la date d'acquisition de l'image satellite. Cet outil a été conçu pour aider les acteurs du développement rural de Madagascar à conseiller les éleveurs sur la façon optimale de gérer les ressources fourragères.
Afficher plus [+] Moins [-]Fig-tree leaves and Sulla hay (Hedysarum flexuosum) in the diet of growing rabbits | Feuilles sèches de Figuier et foin de Sulla (Hedysarum flexuosum) en alimentation du lapin en engraissement Texte intégral
2017
Kadi, Si Ammar | Djellal, F. | Senhadji, Y. | Tiguemit, N. | Gidenne, Thierry | Département des sciences agronomiques, Faculté des sciences biologiques et sciences agronomiques ; Université Mouloud Mammeri [Tizi Ouzou] = Mouloud Mammeri University of Tizi-Ouzou (UMMTO) | Génétique Physiologie et Systèmes d'Elevage (GenPhySE) ; Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Vétérinaire de Toulouse (ENVT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)-École nationale supérieure agronomique de Toulouse (ENSAT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT)
Notice a Reprendre pas de Clé UT au 5 Mai 2017 | 85 Algerian white population rabbits were used to study the effect on the growth performances of fig-tree (Ficus carica, 12.8%, 30.6% and 15 % DM respectively of CP, NDF and ADL) leaves incorporated in pelleted diets in association with Sulla hay (Hedysarum flexuosum). At weaning (35 d, 674±390 g), the rabbits were divided in three groups (individually caged) and received ad libitum one of the three diets during six weeks. The control (T, n=25), diet was classic diet and content barley, dehydrated alfalfa, soya bean meal and wheat bran. The experimental diets were formulated to contain 25% of Sulla hay and either 15% (F1, n =30) or 30% (F2, n =30) dried fig tree leaves in total replacement of dehydrated alfalfa and barley. The diet F1 contained also wheat bran to contain only raw materials available locally. During the whole period (35-77 d), feed intake was at the same level with the three diets (121.3 ± 6.5 g/d), as well as growth (35.3 ± 2.4g/d) and feed conversion ratio (3.37 ± 0.21). According, fig-tree leaves (Ficus carica) could be incorporated in pellet diet for fattening rabbits associated with Sulla ( Hedysarum flexuosum), in total replacement of barley, dehydrated alfalfa and eventually soya bean meal to contain only locally available raw materials. They permitted substantial performances as those of control diet without negative effect on health and the zootechnic performances. | 85 lapins de population locale blanche ont été utilisés pour étudier l’effet sur les performances de croissance de l’incorporation, dans l’aliment granulé, de feuilles de Figuier (Ficus carica ; 12,8% ; 30,6% et 15 % MS respectivement de PB, NDF et ADL) associées au foin de Sulla (Hedysarum flexuosum). Au sevrage (35 j, 674±390 g), les lapins ont été répartis en trois lots homogènes, logés individuellement et ont reçu ad libitum un des trois aliments durant 6 semaines. Le témoin (T, n=25), un aliment classique, contenait de la luzerne déshydratée, du son de blé, de l’orge et du tourteau de soja. Les deux aliments expérimentaux contenaient 25% de foin de Sulla et soit 15% (F1, n =30) soit 30% (F2, n =30) de feuilles séchées de Figuier (FF), en remplacement total de la luzerne et de l’orge. L’aliment F1, équilibré avec du son de blé, ne contenait que des matières premières disponibles localement.Durant la période globale (35-77 j), la consommation a été similaire entre les trois aliments (121 ± 6,5g/j), ainsi que la vitesse de croissance (35,3 ± 2,4g/j) et l'indice de consommation de l’aliment (3,37 ± 0,21). Ainsi, les feuilles de Figuier (Ficus carica) peuvent être incorporées dans l’aliment granulé pour lapins en engraissement associées à du foin de Sulla (Hedysarum flexuosum), en remplacement de l’orge, de la luzerne déshydratée et éventuellement du tourteau de soja pour ne contenir que des matières premières disponibles localement. Elles ont permis des performances appréciables au même niveau que celles de l’aliment témoin sans effets négatifs sur la santé et les performances zootechniques.
Afficher plus [+] Moins [-]Genetic evaluation of lactation persistency and total milk yield in dairy goats Texte intégral
2017
Barbosa Dias de Siqueira, Otávio Henrique Gomes | REIS MOTA, Rodrigo | Oliveira, Hinayah Rojas | Souza Duarte, Darlene Ana | Glória, Leonardo Siqueira | Rodrigues, Marcelo Texeira | Fonseca e Silva, Fabyano
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).
Afficher plus [+] Moins [-]Enhancing farmers’ market power and income in the pig value chain; a case study in Bac Giang province, Vietnam Texte intégral
2017
Le Thi Minh, Chau | Lebailly, Philippe | Tran Quang, Trung
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.
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