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National height system testing using GNSS measurements in Latvia and Lithuania Texto completo
2017
Reke, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Celms, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Reiniks, M., Riga Technical Univ. (Latvia)
As European Union member states – Latvia and Lithuania have changed their national height systems from Baltic Normal Height System 1977 to European Vertical Reference System realizations. Performing practical Global Navigation Satellite System (GNSS) measurements and obtained data mathematical processing, there is a possibility to calculate point height difference between GNSS data and data of 1st order levelling networks. The aim of the research is to gain insight for methodology development of geodetic point height testing using GNSS measurements. To achieve the goal following tasks are set: 1) perform GNSS measurements of first order levelling network in Latvia and Lithuania; 2) do data processing to get point ellipsoidal height and compare with the point normal height; 3) detect technically feasible accuracy of geoid model for precise height measurements with GNSS method within research area. Performing GNSS measurements at the same time in the territory of Latvia and Lithuania, the experience of mutual cross-border cooperation was accumulated. The results were adjusted with academic software package Bernese and were obtained point ellipsoidal and normal heights. The height measurement accuracy using GNSS method depends on geoid model accuracy and more precise results can be obtained increasing used geoid model accuracy to 1.5 to 2 cm.
Mostrar más [+] Menos [-]The comparison of commercially available β-galactosidases for dairy industry: review Texto completo
2017
Zolnere, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Agriculture, Jelgava (Latvia)
β-galactosidase (EC 3.2.1.23) is one of the widely used enzymes for lactose-free milk production and whey permeate treatment. Enzymes can be obtained from microorganisms, plants and animals. Nowadays, microorganisms are becoming an important source for production of commercially available enzymes, which are of great interest and offer several advantages such as easy handling and high production yield. The aim of this review was to summarize findings of research articles on the application of commercially available β-galactosidase preparates in dairy industry, to analyse and compare the most suitable β-galactosidase commercial preparates for lactose hydrolysis. The results showed that the main factor to choose an appropriate β-galactosidase for lactose hydrolysis was reaction condition. Enzymes from microorganisms contain a wide range of optimal pH from 4.0 (Penicillium simplicissimum and Aspergillus niger) to 8.5 (Bacillus subtilis). The greatest commercial potential has enzymes obtained from fungi (Aspergillus oryzae and Aspergillus niger) and yeasts (Kluyveromyces lactis and Kluyveromyces fragilis). Fungal origin enzymes are more suitable for the hydrolysis of lactose in acid whey due to its acidic pH but yeasts origin enzymes for milk and sweet whey. In the study, commercial preparates from different suppliers with the purpose to analyse their lactose hydrolysis potential and give more detailed characteristics of each preparate advantages and drawbacks were also summarized.
Mostrar más [+] Menos [-]A preliminary study on essential minerals in human milk: association with dietary habits Texto completo
2017
Aumeistere, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ciprovica, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Zavadska, D., Riga Stradins Univ. (Latvia) | Bavrins, K., Institute of Food Safety, Animal Health and Environment BIOR, Riga (Latvia)
Human milk provides infant with the required nutrients for growth and development. The aim of preliminary study was to determine macro- and micronutrients content in mature human milk among lactating women residing in Latvia and dietary habits affecting it. The study was carried out from November 2016 to February 2017. In total, 24 pooled diurnal milk samples were collected from mothers whose infants had reached the age of at least two months. Personal information of each participant was recorded, including mother’s age, weight and height parameters, sex and age of an infant, parity, breastfeeding pattern, milk expression method used for sampling. Eating habits were obtained using Monthly Food Frequency Questionnaire. Analysed elements were determined using inductively coupled plasma mass spectrometry (ICP‑MS Agilent 7700x, Japan). Concentrations ranged from 227.52 to 398.34 mg LE-1 for calcium, 58.56 – 256.38 mg LE-1 for sodium, 445.33 – 736.71 mg LE-1 for potassium, 25.73 – 49.52 mg LE-1 for magnesium, till 3.17 mg LE-1 for iron, 0.28 – 2.77 mg LE-1 for zinc, 0.06 – 0.43 mg LE-1 for copper, 2.00 – 44.00 µg LE-1 for manganese, 1.00 –10.00 µg LE-1 for chrome which is comparable to data obtained from other studies although chrome and manganese concentration was even higher than observed in literature. Cobalt and selenium content was below detection limit. Zinc content in human milk negatively correlated with baby’s age (p is less than 0.05). The content of majority of essential minerals in human milk was affected by mother’s dietary habits; however, more samples need to be analysed for representative conclusions.
Mostrar más [+] Menos [-]Quality evaluation of potato and vegetable crisps in Latvian market Texto completo
2017
Kalnina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Straumite, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kruma, Z., Latvia Univ. of Agriculture, Jelgava (Latvia) | Sabovics, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kince, T., Latvia Univ. of Agriculture, Jelgava (Latvia)
Salty snacks are popular appetizers consumed between meals and are one of favourite components of menu at different social gatherings and private celebrations. Consumers base their choice of snacks not only on flavour and smell of product, but also on different kinds of parameters like colour, texture and nutritional value as well as other information labelled on packaging. Typically salty snacks are associated with potato (Solanum tuberosum) crisps, but in present paper there were viewed also vegetable crisps and snacks. The aim of this research was to evaluate nutritional value and physical quality of potato and vegetable crisps and wholegrain snacks in Latvian market. From January to March 2017, 22 potato and vegetable crisps and wholegrain snack samples from Latvian market were analysed. For all samples, information on the labels was analysed as well as salt content, thickness, crispness and colour using standard methods. For 31.8% of the investigated samples, presented information on label and determined salt content do not differ significantly (p is greater than 0.05). That means that 68.2% of the analysed potato, vegetable crisps and snacks on the packaging labels have represented incorrect salt content. Positive moderate correlation (r = 0.489) between potato and vegetable crisps thickness and crispness was found out. Raw materials and ingredients of samples directly impact colour values. If a sample contains beetroot, the colour results would indicate dark red. All potato crisps colour values point out light yellow colour.
Mostrar más [+] Menos [-]Immunogenicity of the Newcastle disease virus vaccine La Sota, in introduced birds under intensive and extensive management conditions Texto completo
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.
Mostrar más [+] Menos [-]Développement d'un outil cartographique pour la gestion des ressources pastorales par une approche combinée de télédétection et de modélisation Texto completo
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.
Mostrar más [+] Menos [-]Body condition score, some nutritional parameters in plasma, and subsequent reproductive performance of Montbéliarde cows in Algeria Texto completo
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.
Mostrar más [+] Menos [-]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 Texto completo
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.
Mostrar más [+] Menos [-]Genetic evaluation of lactation persistency and total milk yield in dairy goats Texto completo
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).
Mostrar más [+] Menos [-]Enhancing farmers’ market power and income in the pig value chain; a case study in Bac Giang province, Vietnam Texto completo
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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