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1.
Veterinary Research Communications - Avian pathogenic Escherichia coli (APEC) is responsible for colibacillosis in poultry. APEC remains a constant problem for the poultry industry, despite the use...  相似文献   
2.
Bruchidius andrewesi Pic. has been recorded as a serious pest of pods and seeds of Acacia tortilis in the Thar desert of India. Pest infestation on developing pods and its relationship with morphological traits is reported. Pod infestation varied from 5 to 19% with 5–29% infestation of seeds. Infestation of pods is directly related to infestation of seed (r = 0.72**), and both pod and seed infestation are also directly correlated with loss in seed biomass (r = 0.79** and R = 0.88**). The infestation of pods starts in November and increases steady until harvest. Seeds kept in the laboratory for further studies were found to be 100% infested with B. andrewesi, as the insect multiplied faster under these conditions. The heavy infestation is damaging not only to A. tortilis but also to other leguminous trees of the desert. Bruchidius andrewesi has also been found on pods and seeds of Prosopis cineraria, an important indigenous tree of the region.  相似文献   
3.
During the last decades, physiological effects of oestrogens have been increasingly explored by scientists and biotechnologists. Estrogens exert a wide range of effects on a large variety of cell types. Oestrogen and its receptors are essential for sexual development and reproduction. Estrogen receptor alpha is a nuclear receptor activated by the hormone oestrogen. In male, ERα is encoded by the gene estrogen receptor gene 1 (ESR1), responsible for better fertility. The ESR1 is involved in the reabsorption of luminal fluid during the transit of spermatozoa from the testis to the head of the epididymis which is important for their survival and maturation during epididymal storage. The absence of ESR1 leads to reduced epididymal sperm content, reduced sperm motility and fertilizing ability. Therefore, this is a good startby to study the expression pattern of estrogen receptor 1 gene in high‐fertile (G1) and low‐fertile (G2) bucks of Jamunapari and Barbari breeds identified on the basis of seminal quality traits and fertility trials. RNA was extracted from the tissues by TRIzol method. The identification and expression pattern of caprine ESR1 gene was analysed by real‐time PCR (Roche LC‐480). Our work shows that the relative quantification by RT‐PCR indicates more fold in head of epididymis as compared to spleen of caprine ESR1 gene. Furthermore, the RT‐PCR indicated that fertile bucks of Jamunapari breed have more fold value as compared to Barbari breed in respect of reproductive organ.  相似文献   
4.
Most of the hybrid seed in chilli are produced manually, but the use of male sterility (MS) can reduce the cost of hybrid seed production. MS‐12, a nuclear male‐sterile (NMS) line developed at Punjab Agricultural University, Ludhiana (India), has been utilized to develop commercial F1 hybrids. A recessive gene, designated as ms10, governs MS in MS‐12. Due to recessive gene control, development of new NMS lines incorporating ms10 gene is tedious and time‐consuming. We identified SSR markers AVRDC‐PP12 and AVRDC_MD997* linked to the ms10 gene. A total of 558 primer pairs were screened following bulked segregant analysis (BSA). Linkage analysis in 210 F2 plants indicated that the two SSR markers were linked to the ms10 gene and the marker AVRDC‐PP12 was closest to the gene at 7.2 cM distance. The marker was mapped to chromosome 1 at genome position 175 694 513 to 175 694 644. Until more closely linked markers are developed, the marker AVRDC‐PP12 would facilitate transfer of ms10 gene through marker‐assisted selection (MAS). Fine mapping would lead to cloning of the ms10 gene.  相似文献   
5.
The spotted stem borer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) is being successfully reared on artificial diets for screening programmes. Besides quality characteristics of the diet, rearing density and adult nutrition have significant implications on the successful mass multiplication of lepidopterans. The performance of C. partellus moths was assessed on different adult diets (water and sugar solution) and compared with unfed adults. Further, three pairing densities, viz. 2, 5 and 8 pairs/oviposition jar (1177.5 cm3) were compared for their effect on C. partellus longevity and fecundity. In another experiment, different larval densities (100, 150 and 200 neonate larvae/diet jar) were evaluated for their effect on the larval survival. Water-fed moths (both males and females) lived longer (7.32 and 7.26 days, respectively) and showed higher fecundity (307.17 eggs) than the sugar-fed or unfed moths. The latter, however, showed better egg hatchability (76.55%) than the water- or sugar-fed moths (60.45 and 50.59%, respectively). The longevity (5.67 days) and fecundity (258.46 eggs) were significantly greater at pairing density of 2 pairs/jar. The larval survival was higher (58.50%) at rearing density of 100 larvae/jar. The neonate larval release into diet jars was compared with conventional egg release and both modes were no different with respect to larval survival.  相似文献   
6.
To study the individual and combined effects of fumonisin B1 (FB1) toxicity and Salmonella serotype Gallinarum infection, Japanese quail (Coturnix coturnix japonica) were fed Fusarium moniliforme culture material (2.5%), 150 mg FB1/kg ration, and were subsequently challenged orally with Salmonella Gallinarum organisms (2 x 10(4) colony-forming units) at 21 days of age. The chicks were fed culture material containing FB1 from day 5 till the end of the experiment. After being infected with Salmonella Gallinarum, observations were made 1, 2, 3, 5, 7, 10, 14, and 21 days postinfection. The clinical signs of diarrhea with bloody discharges were more pronounced in the Salmonella-infected birds on the FB1 diet. Mortality caused by Salmonella Gallinarum increased by 12% in the presence of FB1. Mean body weights in both the Salmonella-infected and FB1-fed groups were significantly lower than those of the controls at almost all intervals. Mean values of hemoglobin, packed cell volume, and total erythrocyte count were slightly higher in birds fed FB1 but were lower in the Salmonella Gallinarum groups fed FB1 and plain chick mash. Anemia was evident, between 5 and 10 days postinfection, in quail chicks infected with Salmonella Gallinarum alone. Total leukocyte counts were higher in Salmonella-infected and FB1-fed groups because of an increase in the number of heterophils and lymphocytes. However, the increase in lymphocyte response to infection was lower by 4.27%-30.09% between 3 and 21 days postinfection in the FB1-fed chicks compared with chicks infected with Salmonella Gallinarum. Alanine transaminase and total serum protein were slightly higher in both the infected and FB1-fed groups. This study revealed that the continuous presence of fumonisins in the diets of quail chicks might increase the susceptibility to or the severity of Salmonella Gallinarum infection.  相似文献   
7.
1. A study was conducted to evaluate the effects of ochratoxin A (OA) on broiler chicks challenged with Salmonella gallinarum. 2. One hundred and seventy-six 1-d-old broiler chicks were divided into two groups of 88 chicks each, with one group fed on a control mash diet and the other given a mash diet containing 2 ppm OA. On d 14, each group was further subdivided into two groups with one group infected with S. gallinarum and the other uninfected. 3. Following S. gallinarum inoculation on d 14, 4 birds from each group were killed at 1, 2, 3, 5, 7, 10, 14 and 21 d post inoculation. 4. S. gallinarum infection caused dullness, depression, weakness, increased thirst, droopy wings, ruffled feathers and greenish-yellow diarrhoea. S. gallinarum infection in the absence of OA caused 11.5% mortality which increased to 28.8% in the presence of OA. 5. Decreased body weight and reduced feed intake were observed in chicks fed on the diet containing OA. S. gallinarum infection also reduced the body weights of chicks, with the effects being more marked in chicks receiving OA. The OA diet led to increased serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, uric acid and creatinine, and decreased levels of total proteins, albumin, globulins, calcium and phosphorus. S. gallinarum infection did not cause significant alteration in any of the serum biochemical parameters. 6. Mortality and the severity of S. gallinarum infection in broiler chicks were increased by the presence of OA in the diet.  相似文献   
8.
Plant resistance has become an important component of integrated pest management (IPM) for management of whitefly, Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), an important pest of cotton in India. The present studies were undertaken to standardize the plant stage and identify resistant cotton genotypes against whitefly. Nine plant stages of F846, a susceptible cotton genotype, were exposed to whitefly for 25 days under no-choice conditions. The population buildup (eggs, nymphs, pupae and adults) was recorded. The 12-, 14- and 16-leaf stages were suitable for plant resistance studies against whitefly, and the 14-leaf stage was taken for further studies. Ten cotton genotypes of Gossypium hirsutum and two of G. arboreum were covered with split cages in which five pairs of B. tabaci (F1) were released. The population buildup was recorded to categorize genotypes as resistant, moderately resistant, moderately susceptible or susceptible. The experiment was repeated with F2 and F3 generation whiteflies. Based on overall average score of three experiments, LD694 was rated as resistant; LK861, Supriya, RS2013, CNH911 and PA183 as moderately resistant; IS-376/4/1/20/72, NHH44, TxMaroon2-78, Bt 6304 and RS2098 as moderately susceptible; and F846 as susceptible. LD694 was found to be resistant in three consecutive generations of whitefly.  相似文献   
9.
Bell pepper (Capsicum annuum L. var. grossum Sendt.) production is often constrained by prevailing sub-optimal temperature conditions. The treatments that enhance earliness and extend availability period may substantially increase value of the crop. This two-year study (2010–11 and 2011–12) was conducted to investigate the comparative effect of two growing environments (open field vs. polyhouse), three planting dates (15 October, 30 October, and 15 November), and four mulch treatments (black polythene, clear polythene, paddy straw, and no-mulch) on growth and yield of bell pepper. The highest fruit number, fruit weight, early yield, marketable yield, and total yield were obtained when the crop was planted in the polyhouse on 30 October under black polythene mulch. Thus, the use of polyhouse and black plastic mulch, when combined with appropriate planting date, improves early and total yields of bell pepper in areas where the production is constrained by sub-optimal temperature conditions.  相似文献   
10.
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