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131.
Vitamin A deficiency is widely prevailing in children and women of developing countries. Deficiency of vitamin A causes night blindness, growth retardation, xerophthalmia and increases the susceptibility against epidemic diseases. Among different interventions of overcoming malnutrition, biofortification is the most acceptable and preferred intervention among researchers, growers and consumers. Maize is grown and consumed in those regions where vitamin A deficiency is most prevalent; thus, targeting this crop for provitamin A biofortification is the most appropriate solution. Different breeding strategies including diversity analysis, introduction and stability analysis of exotic germplasm, hybridization, heterosis breeding, mutagenesis and marker‐assisted selection are practised for exploring maize germplasm and development of provitamin A‐enriched cultivars. Genome‐wide association selection and development of transgenic maize genotypes are also being practised, whereas RNA interference and genome editing tools could also be used as potential strategies for provitamin A biofortification of maize genotypes. The use of these breeding strategies for provitamin A biofortification of maize is comprehensively reviewed to provide a working outline for maize breeders.  相似文献   
132.
Mass flux assessment can provide information that is essential for a sustainable management of elements in agricultural soils. In this article, we present an assessment of regional-scale averages of zinc (Zn) fluxes into agricultural soils and crops of central Iran for the period 1997–2011, using available databases such as regional agricultural statistics. The basic units of the balances were 15 townships of the provinces Qom, Isfahan and Fars. Averaged over the entire study region, the net Zn input into arable soil resulting from all fertilizer inputs – Zn removal with harvested crops was 1515 g ha?1 yr?1 across the entire region, with a range of 438–3009 g ha?1 yr?1 among townships. Estimated average Zn inputs with manure, mineral fertilizers, sewage sludge and compost were 1254, 531, 19 and 7 g ha?1 yr?1, respectively. The input-to-output ratio of these fluxes ranged from 1.8 to 12.9 among townships and averaged 6.1 for the entire study area. Considering that outputs other than with crop harvests are minor, Zn stocks are rapidly building up in the soils of the study region. Uncertainties in the manure and crop removal data were the main sources of estimation uncertainty in this study.  相似文献   
133.
Microinjection of exogenous DNA into the cytoplasm of matured oocytes or zygotes is a promising technique to generate transgenic animals. However, the data about the microinjection time and procedure in sheep are limited and have not treated in detail. To obtain more in-depth information, the Sarda sheep oocytes from abattoir-derived ovaries were subjected to IVM and IVF. Then, the GFP plasmid as a reporter gene was injected into the cytoplasm of MII oocytes (n: 95) and zygotes at different post-insemination intervals (6–8 hpi, n: 120; 8–10 hpi, n: 122; 10–12 hpi, n: 110 and 12–14 hpi, n: 96). There were no significant differences in the cleavage rates between the groups. However, blastocyst rate of injected zygotes at all-time intervals was significantly lower than injected MII oocytes and control group (< 0.05). Interestingly, the proportion of GFP-positive embryos was higher at 8–10 hpi compared with other injected groups (4 % versus 0 %, < 0.01). Among these, the proportion of mosaic embryos was high and two of those embryos developed to the blastocyst stage. In conclusion, we settled on the cytoplasmic microinjection of GFP plasmid at 8–10 hpi as an optimized time point for the production of transgenic sheep and subsequent experiments.  相似文献   
134.

Bluetongue virus (BTV), a member of Orbivirus genus (family Reoviridae), is a non-contagious infection of domestic and wild ruminants. The current study was designed to detect various serotypes of BTV in small ruminants of Khyber Pakhtunkhwa (KPK) province of Pakistan, along with their effects on hemato-biochemical parameters. A total of 408 serum samples in four districts (Mansehra, Abbottabad, Swabi, and Kohat) of KPK from small ruminants were screened based on competitive ELISA (cELISA). A total of 204 (50%) samples were found positive for BTV group–specific antibodies. The seropositive samples were processed for the detection of BTV serotypes through real-time polymerase chain reaction (qPCR). Out of 204 cELISA-positive samples, 60 (29.41%) were found positive through qPCR. Three serotypes [6, 8, 9] were detected from Mansehra District and two from Kohat [2, 8] and Abbottabad [6, 8], while only one from Swabi [8]. The serotype “8” was found consistently in all the four study districts. A significant (p?<?0.05) increase in the level of blood urea nitrogen (BUN) and alkaline phosphatase (ALP) was recorded in goats, whereas aspartate aminotransferase (AST) in sheep infected with BTV, compared to healthy animals. The hematological parameters showed significantly (p?<?0.05) raised total leucocyte count (TLC) in both sheep and goats, whereas only hematocrit (HCT) value was increased significantly (p?<?0.05) in infected sheep. This is the first report on serotyping of BTV among small ruminants in Pakistan.

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135.
Serum IgG, IgM and IgA antibody response in 20 cattle naturally infected with Mycobacterium paratuberculosis and in 15 non-infected cattle were measured by enzyme-linked immunosorbent assay. A strong IgG response was detected in 16 (80%) of the infected animals. Diagnostic levels of IgM were detectable in all of the infected animals as well as in 8 (53%) of the non-infected animals. Animals with paratuberculosis had a very weak specific serum IgA response and this appears to be of little value in detection of infection in these animals.  相似文献   
136.
A 10-month-old Arabian foal was evaluated for a suspected immunoglobulin (Ig) M deficiency. Decreased to nondetectable concentrations of IgM, IgA, and IgG (T), and a normal concentration of IgG, were present. Results of in vitro testing of the blood lymphocyte blastogenesis showed a weak response to the B-cell mitogen, lipopolysaccharide (LPS), but normal responses to T-cell mitogens. Results of postmortem examination showed synovitis of the left tibiotarsal and both scapulohumeral joints. Atrophy and edema of the lymph nodes and lymphocyte depletion in the thymus and spleen were seen. A subacute inflammatory infiltrate was observed in the kidney, synovium, liver, and brain. Etiologic agents were not identified. This case represents a previously unreported form of immunodeficiency disease in the horse.  相似文献   
137.
Tropical Animal Health and Production - Based on current knowledge, C16 and C18 fatty acids (FA) are considered the most functional FA in hepatic metabolism. Although these FAs have been...  相似文献   
138.
The present study aims to comparatively evaluate the effects of different doses of intravenous xylazine and medetomidine on sedation and antinociception scores, and physiological and laboratory parameters in dromedary calves. Thirty clinically healthy male dromedary calves 15 ± 2 weeks old and weighing 95 ± 5.5 kg were studied. Two groups received xylazine at low (0.2 mg/kg) and high (0.4 mg/kg) doses. Two groups received medetomidine at low (10 µg/kg) and high (20 µg/kg) doses. One group received normal saline. Sedation signs were scored using a 3‐point scale. Analgesic effect was analyzed using pinpricks. Data were analyzed by one‐way ANOVA and Mann–Whitney U‐tests. Sedation and antinociception scores of the animals 1 hr after receiving the higher dose of xylazine and medetomidine were significantly higher than that of other groups. Compared with other studied groups, the animals receiving the higher dose of xylazine showed significantly higher potassium and creatinine serum levels after 24 hr. Doses as high as 0.4 mg/kg for xylazine and 20 µg/kg for medetomidine can be considered safe and useful for procedures associated with mild pain in dromedary calves.  相似文献   
139.
Summary The immune responses following vaccination and resistance to diseases were compared in male and female meat poultry breeders of the same flock. Female poultry breeders maintained antibody titres to Newcastle disease virus and infectious bronchitis virus up to the fifty-fifth day following vaccination, whereas those of the males declined significantly over the same period of time (P<0·05). In the same flock, outbreaks of Gumboro disease (60 to 62 days of age), coccidiosis (68 to 74 days of age) and aortic rupture (99 to 112 days of age) produced significantly higher losses in males. Following vaccination against fowl pox by the wing web method, 96·7% of females had a vaccine reaction (vaccine take) compared to none of the males. Immune injuries, following vaccination, were observed in 85% of the males compared to none of the females. The immune injuries included appearance of facial papules, vesicles, and reddish brown to black scabs.
Comparacion De La Inmunidad Y Resistencia A Enfermedades En Machos Y Hembras Reproductores Aviares En El Libano
Resumen La respuesta immune después de la vacunación y la resistencia a infermidad des fue comparada en reproductores machos y hembras en un plantiel de pollos de carne. Las hembras reproductoras mantuvieron los títulos de anticuerpos contra Newcastle y bronquitis infecciosa hasta los cincuenta y cinco días después de la vacunación, mientras que los niveles de anticuerpos de los machos declinaron significativamente durante el mismo período de tiempo (P<0·05). En el mismo plantel, ocurrieron brotes de Gumboro (60 a 62 días de edad), coccidiosis (68 a 74 dias de edad) y ruptura aórtica (99 a 112 diás de edad) con pérdidas mayores en machos. Desués de la vacunación contra viruela utilizando el método escarificación en el ala membrana, el 96·7% de las hembras reaccionó inflamatoriamente, y ninguno de los machos. Las lesiones inmunes después de la vacunación, se observaron en el 85% de los machos y en ninguna de las hembras. Las lesiones inmunes consistieron en pápulas faciales, vesículas, y costras negras-rojisas.

Comparison De L'immunite Et De La Resistance Aux Maladies Chez Des Reproducteurs Males Et Femelles Dans Un Elevage De Volailles De Chair Au Liban
Résumé Les auteurs ont comparé les réponses immunitaires post-vaccinales et la résistance aux maladies chez des reproducteurs mâles et femelles appartenant au même élevage de volailles de chair. Les reproducteurs femelles ont maintenu des titres d'anticorps contre le virus de la maladie de Newcastle et celui de la bronchite infectieuse jusqu'au 55e jour suivant la vaccination alors que ceux des mâles ont connu une baisse significative tout au long de la même période (P<0,05). Dans le même élevage, des foyers de maladie de Gumboro (sur des animaux de 60 à 62 jours), de coccidiose (de 68 à 64 jours), et des ruptures de l'aorte (animaux âgés de 99 à 112 jours), ont eu pour conséquence des pertes significativement plus élevés chez les mâles. A la suite de la vaccination contre la variole aviaire dans le tissu palmaire de l'aile, 96,78% des femelles on montré une réaction vaccinale (= prise du vaccin) aucune n'etant décelée chez les mâles. Quant aux lésions post-immunitaires, elles ont été observées sur 85% des mâles contre aucune chez les femelles. Parmi elles, on a observé l'apparition de papules faciales, de vésicules et de croûtes colorées allant du brun rouge au noir.
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140.
Measurement of soil bulk density is important for understanding the physical, chemical, and biological properties of soil. Accurate and rapid soil bulk density measurement techniques play a significant role in agricultural experimental research. This review is a comprehensive summary of existing measurement methods and evaluates their advantages, disadvantages, potential sources of error, and directions for future development. These techniques can be broadly categorised as direct and indirect methods. Direct methods include core, clod, and excavation sampling, whereas indirect methods include the radiation and regression approaches. The core method is most widely used, but it is time consuming and difficult to use for sampling multiple soil depths. The size of the coring cylinder used, operator experience, sampling depth, and in-situ soil moisture content significantly affect its accuracy. The clod method is suitable for use with heavy clay soils, and its accuracy is dependent on equipment calibration, drying time, and operator experience, but the process is complicated and time consuming. Excavation techniques are most commonly used to evaluate the bulk density of forest soils, but have major limitations as they cannot be used in soils with large pores and their measurement accuracy is strongly influenced by soil texture and the type of analysis selected. The indirect methods appear to have greater accuracy than direct approaches, but have higher costs, are more complex, and require greater operator experience. One such approach uses gamma radiation, and its accuracy is strongly influenced by soil depth. Regression methods are economical as they can make indirect measurements, but these depend on good, quality data of soil texture and organic matter content and geographical and climatic properties. Also, like most of the other approaches, its accuracy decreases with sampling depth.  相似文献   
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