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Open access

E. Al-Shehadah, A. Al-Daoude and M. Jawhar

Abstract

Rhynchosporium secalis, the causal agent of barley scald disease, is a fungus commonly found in the environment. Disease spread within a field and between fields occurs through the aerial dispersal of the fungal spores. However, not much is known about the survival potential of fungal conidia exposed to solar radiation. In the present study, detached conidia of R. secalis were exposed simultaneously in the field to direct sunlight or placed in an adjacent ventilated enclosure in the dark for periods ranging from 0.5 to 8h. In addition, conidia were either exposed or not exposed to UV-C light (254 nm) for periods ranging between 0.5 and 60 min in the laboratory. After exposure, conidia were placed on water agar Petri dishes and allowed to germinate for 24h. Germinability of conidia was reduced by up to 94% after 8h of exposure to solar irradiance (670-860 Wm-2) in the field in comparison to the non-exposed control. Germinability of conidia in the laboratory was reduced up to ~100% by doses of UV-C light of 3.2±0.7 Wm-2. The results of this study will contribute to a better understanding of the relationship between climatic conditions and barley scald epidemics

Open access

Marina Štukelj and Jan Plut

Summary

African swine fever (ASF) is a serious disease of domestic and feral swine mainly because of grave clinical course of the disease and its strong socio-economic impact. Not only there is an extremely high mortality (95–100%) around the time of the first outbreak, live-animal, pork meat and other pork product trade is strongly affected on regional and international level. ASF is a species-specific disease; strength of the clinical signs depends on virulence of a viral strain. Exacerbation of body temperature and dysfunction of respiratory system and gastrointestinal tract are most common occurrences. Lesions can be mostly classed as congestive or hemorrhagic. Epidemiologically, ASF varies substantially among regions, countries and continents due to wide panel of different virus genotypes, population of feral swine and other reservoirs of disease, geographical characteristics and social habits of people. ASF is endemic in Sub-Saharan Africa where soft ticks (Argaside) and chronically infected feral swine population serve as reservoirs. It also became endemic in most parts of Russian Federation. Since 1978, ASF is endemic on Sardinia isle, as it was eradicated in all other parts of Europe. First outbreak in Georgia in 2007 has apparently served for transmission to other eastern European countries. Slovenia is currently still ASF-free but disease has already reached some relatively nearby countries (Poland, Romania, Moldova, Czech Republic and Hungary). There is no anti-ASF vaccine currently available ad specific treatment has not been described. Therefore rapid diagnostics and implementation of strict biosecurity measures play a key role in prevention of further transmission.

Open access

Karolina Stasiak, Stanisław Kondracki and Maria Iwanina

Abstract

The aim of the study was to determine the relationship of sperm morphology with age of males, ejaculate concentration and volume, as well as with acrosin activity determined in sperm acrosome extracts. The study used manually collected ejaculates from 9 male arctic foxes, including 6 young males aged one year and 3 older males (between 3 and 5 years of age). All of the 39 ejaculates used in the study were classified as normal based on motility exceeding 70%. The ejaculates collected from the foxes were evaluated for volume, sperm concentration and frequency of morphological changes including primary and secondary defects. The spermiograms of the male arctic foxes were classified according to a six-grade subjective scale. In addition, acrosin activity was determined in the sperm acrosome extracts. The data were analysed using the criteria of male age, sperm concentration, ejaculate volume, and acrosin activity. The morphology of arctic fox spermatozoa was dependent on the age of the male. A greater number of morphologically altered spermatozoa tended to occur in the ejaculates of young foxes, which were in their first breeding season. In addition, statistical analysis revealed positive relationships between the frequency of morphological changes in sperm and their ejaculate concentration. In contrast, there were no significant correlations between the percentages of morphologically changed spermatozoa and the ejaculate volume and the content of acrosin, which is an indicator of acrosomal integrity. Semen quality is dependent on the number of sperm in ejaculate with morphological defects which prevent oocyte fertilization. Therefore, morphological assessment of semen, which covers both the number and type of morphological changes, is highly useful when selecting appropriate males for reproduction.

Open access

Julia Poyato-Bonilla, María José Sánchez-Guerrero, Rute Dos Santos and Mercedes Valera

Abstract

Coat colour has always been a valuable trait for horse breeders. However, preferences for this feature have changed over the years. In this research, the Pura Raza Español horse (PRE) population was divided into four subpopulations (Grey, Bay, Black and Others), according to the most frequent coat colours and those of their ancestors. The purpose was to analyse genetic variability, reproductive parameters and distances among subpopulations during three key periods in the history of the breed: before 1960, from 1960 to 2000 and after 2000. The subpopulations composed of animals with ancestors with the same coat colour showed higher values of recent inbreeding (ranging from 7.13% to 10.44%) and a greater Nei’s minimum distance between them, as a result of more inbred matings than those carried out in families with members with different coat colours. Non-pure subpopulations also showed more similar recent inbreeding values (between 6.63% and 6.74%). Strikingly, the productive life of Pure bay, Pure black and other subpopulations with minority coat colours was considerably longer (10.79, 10.08 and 9.11 years, respectively) compared to the values of grey PRE horses (6.01 and 7.98 years), which is the subpopulation with the highest census. These results, together with shorter generation intervals of black stallion-offspring (5.51 years via father-son and 6.39 years via father-daughter) and the fact that this coat colour was not present in the breed until two decades ago, highlight the recent trend towards the breeding of black animals.

Open access

Christoph Husemann, Vesna Rodić and Jovana Husemann

Summary

Phosphorus is an essential nutrient for all forms of life, which means that food cannot be produced without it. As the phosphate rock (concentrated source of phosphorus) is a non-renewable and finite resource, with no substitute, without more sustainable management of phosphorus its deposits could be depleted in a rather short period. In addition, much of phosphorus eventually ends up in environment, where it causes pollution. Hence, one could say that the lack of phosphorus and its inappropriate management could be a bottleneck for a sustainable food supply and agricultural development in general. Nevertheless, unlike some other challenges that modern agriculture has to face (for example, water and energy scarcity, climate changes etc) the problem of phosphorus limited availability and accessibility has been largely neglected until recently. This paper’s particular intention is to explain why phosphorus management is one of key issues for the sustainable food supply and agricultural development, which factors have to be considered when dealing with this topic and which technologies could be applied as potential solutions. One solution to become independent from the fossil deposits of phosphorus might be its extraction from wastewater, which could contribute significantly to overcome the looming phosphorus and growing environmental crisis.

Open access

Jelena Golijan, Aleksandar Popović and Ljubiša Živanović

Summary

Over the past few years, organic agricultural production has increased globally. This type of production is regulated by numerous laws and concomitant regulations, whereas the basic principles of organic production development are prescribed by the IFOAM standards and the European Union. Seed production is of immense importance to organic agricultural systems as the use of certified seed is crucial in preserving organic production. Prior to 2009, certified organic seed had not been produced in the Republic of Serbia, and producers had used either landrace seeds or chemically untreated conventional seeds. Of the total area devoted to organic farming in the Republic of Serbia (14,357.96 ha), seed production accounts for only 8.4 ha, with uneven distribution over regions. The highest organic seed production (5.2 ha) has been recorded in the region of Vojvodina. However, there is still a lack of certified organic seed in the country, emphasizing the need for organic seed breeding and production in the future.

Open access

M. Jamal Hajjar and M. Al-Masoud

Abstract

Lethal and sublethal effects of ten insecticides commonly used in date palm production in Saudi Arabia were assessed in the laboratory against adults of Trichogramma cacoeciae, an important egg parasitoid of the dried fruit moth Ephestia calidella. Bioassays were conducted according to the standard protocol of the International Organization for Biological Control IOBC/WPRS/Working Group ‘Pesticides and Beneficial Organisms’. Our results showed that cypermethrin, deltamethrin, malathion, phenthoate, methomyl, and carbosulfan were moderately harmful (IOBC Class 3) to the parasitoid. The botanical insecticides azadirachtin and matrine were moderately harmful (IOBC Class 3) and slightly harmful (IOBC Class 2), respectively. The insect growth regulator pyriproxyfen was slightly harmful, whereas bistrifluron was harmless (IOBC Class 1). Regarding sublethal effects, the parasitism ratios compared to control were reduced by pyriproxyfen and azadirachtin to 49.0% and 58.0%, respectively; hence they are classified as slightly harmful insecticides (IOBC Class 2). Bistrifluron and matrine were harmless (IOBC Class 1) as parasitism ratios were reduced by 9.2% and 27.6%, respectively. Longevity of adults exposed to bistrifluron and matrine (3.6 and 3.3 days, respectively) and to pyriproxyfen and azadirachtin (1.7 and 1.3 days, respectively) was significantly lower than that in control (4.67 days). In semi-field tests, residues of most insecticides on leaves of tomato, a common host plant of lepidopteran pests parasitized by T. cacoeciae, were considered moderately harmful to harmful based on parasitoid mortality at 24 h post-treatment whereas they were slightly harmful at 7 and 14 days post-treatment

Open access

Sylwester Świątkiewicz, Anna Arczewska-Włosek, Witold Szczurek, Jolanta Calik, Józefa Krawczyk and Damian Józefiak

Abstract

The trial with 240 caged ISA Brown laying hens was performed to evaluate the effect of selected feed additives on mineral utilisation as well as biomechanical (breaking strength, yielding load, stiffness) and geometrical (cortex thickness, cross-section area, weight, length) indices of tibia and femur bones. At 26 wks of age the layers were randomly assigned to 10 treatments with 12 replicates (cages) of two birds. In the study a 2 × 5 experimental scheme was used i.e. to 70 wks of age, the layers were fed isocaloric and isonitrogenous experimental diets containing reduced (3.20%) or standard (3.70%) Ca level. The diets with both Ca levels were either not supplemented, or supplemented with the studied feed additives i.e. sodium butyrate, probiotic bacteria, herbal extract blend and chitosan. There were no statistically significant effects of the experimental factors on the indices of the tibia bones. However, the diet with reduced Ca level decreased bone breaking strength, yielding load, stiffness, and mineralisation of the femur bones (P<0.05). The majority of used feed supplements, i.e. probiotic, herb extracts, and chitosan, increased biomechanical indices (breaking strength and yielding load) and mineralisation of the femur bones (P<0.05). Neither dietary Ca level nor feed additives affected dry matter, organic matter, ether extract, N-free extracts, crude fibre and ash digestibility, and P retention and excretion; however, Ca excretion and retention was lower in the hens fed the diets with reduced Ca level (P<0.05). Relative Ca retention (Ca retained as % of Ca intake) was improved by diet supplementation with probiotic, herb extracts and chitosan (P<0.05). In conclusion, this study has shown that decreased Ca dietary level (3.20%) can negatively affect bone quality in layers, while probiotic, herb extracts and chitosan addition may improve the selected biomechanical indices of the femurs, irrespective of Ca dietary concentration.

Open access

Ewa Tomaszewska, Siemowit Muszyński, Piotr Dobrowolski, Małgorzata Kwiecień, Renata Klebaniuk, Sylwia Szymańczyk, Agnieszka Tomczyk, Sylwester Kowalik, Anna Milczarek and Izabela Świetlicka

Abstract

Faba bean (FB) seeds can be a good protein-energy component in animal feed. However, the presence of anti-nutritional substances is a negative feature of FB seeds. The aim of this study was to examine the influence of different levels of unprocessed FB seeds in feed on the gut-bone axis and metabolic profile in broilers. Ninety six, 1-day-old Ross 308 broiler chickens were randomly selected to one of the 3 dietary treatments (32 chickens in each, divided into 8 pens with 4 birds per each pen): the control group fed standard diet with soybean meal and without FB seeds, group I fed 8/15% (starter/grower) of high-tannin FB seeds, and group II fed 16/22% of high-tannin FB seeds. Bone mechanical examination, hematological and serum biochemical analysis as well histomorphometry of small intestine and liver tissue were performed. The intake of high-tannin FB seeds, irrespective of their amount, did not alter the bone geometric, mechanical and densitometric parameters nor influenced basal hematological parameters, however it resulted in: decreased serum concentration of total cholesterol and calcium; a reduced longitudinal myenteron of small intestine; increased mucosa and villus epithelium thickness, villus length, thickness and absorptive surface in duodenum; increased number of active crypts in jejunum; unchanged collagen area, intercellular space, and total cell number in the liver; decreased number of multinuclear hepatocyte cells. Moreover, the livers of birds fed the higher dose of high-tannin FB seeds had lymphocytic infiltrates in portal tracts and sinusoids. Feeding of unprocessed high-tannin FB seeds exerted an influence on the gastrointestinal tract by increased absorptive surface. In conclusion, the dietary inclusion of unprocessed high-tannin FB seeds had no negative effects on broiler growth, tibial bone mechanical properties and intestinal characteristics. Unprocessed high-tannin FB seeds may be used in broiler diets, but their dietary levels should not be higher than those discussed.

Open access

Xin Jian Lei, Hyeok Min Yun, Yi Yang and In Ho Kim

Abstract

This study was conducted to evaluate the effects of dietary β-glucan supplementation on growth performance, nutrient digestibility, blood profiles, and fecal characteristics in weaner pigs. A total of 140 weaner pigs [(Yorkshire × Landrace) × Duroc] with an average body weight of 6.37±1.14 kg were allotted to one of the following dietary treatments: 1) negative control (NC, basal diet); 2) positive control (PC, basal diet supplemented with 39 ppm Tiamulin); 3) basal diet supplemented with 0.1% β-glucan (G1); 4) basal diet supplemented with 0.2% β-glucan (G2). During days 22 to 42 and 1 to 42, pigs offered PC and G2 diets grew faster than those offered NC diet (P<0.05). Additionally, during the same periods, pigs fed G2 and PC diets exhibited improved gain:feed ratio compared to pigs receiving NC and G1 diets (P<0.05). Pigs fed G2 diet exhibited higher coefficient of total tract apparent digestibility of dry matter than those fed NC diet (P<0.05). There were no differences on blood profiles, fecal scores, fecal moisture, and fecal pH (P>0.05). Fecal lactic acid bacteria counts in G2 treatment were higher compared with PC and NC treatments (P<0.05). Coliform bacteria concentrations were decreased in pigs fed PC and G2 diets compared with those fed NC diet (P<0.05). In conclusion, the results of the current study indicate that dietary supplementation of 0.2% β-glucan can improve growth performance and dry matter digestibility, increase fecal lactic acid bacteria concentration but decrease fecal coliform bacteria concentration in weaner pigs.