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101.
Extracts of the leaves of Securinega leucopyrus exhibited a broad spectrum of antimicrobial activity.  相似文献   
102.
Infectious bovine keratoconjunctivitis (IBK) is an acute disease caused by Moraxella bovis (Mb). Several factors may predispose animals to an IBK outbreak; one commonly observed is infection with bovine herpes virus type 1 (BHV-1). The aim of this study was to investigate the dynamics of BHV-1 virus infection and its relation with clinical cases of IBK in weaned calves from a beef herd with a high prevalence of lesions caused by Mb. Sampling was carried out in six stages and included conjunctival swabs for isolating Mb as well as blood samples for identifying antibodies specific for BHV-1. A score for IBK lesions after observing each eye was determined. The findings of this study showed a high prevalence of BHV-1 virus infection (100% of animals were infected at the end of the trial); 67% of animals were culture-positive for Mb, but low rates of clinical IBK (19% of calves affected) were detected at the end of the trial. These results suggest that infection with BHV-1 did not predispose these animals to IBK, and that Mb infection produced clinical and subclinical disease in the absence of BHV-1 co-infection.  相似文献   
103.

The present research work entitled “Correlation of testicular ultrasonography, testicular biometry, serum testosterone levels and seminal attributes in pre- and post-pubertal age for breeding soundness evaluation in Osmanabadi bucks” was undertaken in 18 healthy Osmanabadi bucks from the Instructional Livestock Farm Complex, Bombay Veterinary College, Mumbai, Maharashtra. The body weight (kg), scrotal circumference (cm) and testicular biometry (cm) of post-weaning 18 Osmanabadi male kids was recorded every 15 days from weaning, i.e., 120?±?10 days along with serum testosterone (ng/ml) by radioimmunoassay method at monthly intervals for the next 6 months. Semen was collected six times on the seventh month onward during post-pubertal age at 15-day interval from 18 bucks. The semen was evaluated for macroscopic and microscopic tests. The body weight increased from 14.45?±?0.67 to 19.57?±?0.70 kg from four to nine and a half months of age. The average daily body weight gain was 31.27 g. Maximum body weight gain was 01.19?±?0.16 kg from 5 to 6 followed by 01.15?±?0.16 kg from 4 to 5 months of age. The scrotal circumference increased from 17.22?±?0.56 to 19.03?±?0.55 cm from four to nine and a half months of age with maximum increased between 4 and 5 followed by 6 and 7 months of age. The testicular length, width and thickness of right and left testicles were recorded by ultrasonography method. There was increase in mean right and left testicular length, width and thickness from 5.25?±?0.19 to 5.84?±?0.18 and 5.49?±?0.21 to 6.16?±?0.20; 2.99?±?0.12 to 3.32?±?0.12 and 3.10?±?0.13 to 3.44?±?0.12 and 2.97?±?0.12 to 3.16?±?0.12 and 3.06?±?0.12 to 3.31?±?0.11 cm, respectively by ultrasonography, between four to nine and a half months of age. Testicular length, width and thickness gain was at maximum in 5 to 6 months of age. Left testicular length was more than the right testis. Before puberty, there was sudden gain in body weight, testicular length and width. However, scrotal circumference showed significant increase after puberty. Body weight had highest correlation with ultrasonographic left testicular thickness (r?=?1) followed by scrotal circumference, ultrasonographic right and left testicular width, left testicular length, right testicular length and thickness and least by right testicular thickness (r?=?0.95). The semen was thin to thick in consistency and average semen density was 3.10?±?0.05. Average semen volume was 0.81?±?0.02 ml, mass activity, initial motility, live and dead sperm count, abnormal sperm count and sperm concentration were 3.45?±?0.13, 76.16?±?1.16 and 75.16?±?1.28% and 24.84?±?1.28, 12.30?±?0.50% and 2631.04?±?45.74 million/ml, respectively in 18 bucks in six collection at 15 days. There was significant rise in semen volume, mass activity, initial motility and concentration at 8.5 months and live count, density at 9 months of age which indicates the age of sexual maturity is 8.5 to 9 months in Osmanabadi bucks. The body weight had highest positive correlation with mass activity (r?=?98) followed by initial motility, live sperm count and total sperm concentration, semen volume (r?=?76). The scrotal circumference had highest positive correlation with initial motility (r?=?98) followed by live sperm count, total sperm count, mass activity, semen volume (r?=?86). On the other hand, body weight and scrotal circumference were negatively correlated with abnormal and dead sperm count. The mean testosterone concentration increased from 0.02?±?0.004 to 5.75?±?0.80 ng/ml between four and half to nine and half months of age, respectively. There was significant rise (p?<?0.01) up to 1.38?±?0.28 ng/ ml at 6.5 months, i.e., age of puberty and up to 5.75?±?0.80 ng/ml at 9.5 months, i.e., age of sexual maturity. Testosterone had highest positive correlation with testicular length followed by testicular width, length, body weight and scrotal circumference, mass activity, live sperm count, initial motility, while it had highest negative correlation with dead and abnormal sperm count. From the present research work, it was concluded that the scrotal circumference, testicular length, width and thickness increased with increasing body weight. Before puberty, there was sudden gain in body weight, testicular length and width. However, scrotal circumference increased significantly at post-pubertal age. So testicular length, body weight, testicular width in pre pubertal age and scrotal circumference post-pubertal age can be used as indicator for selection of Osmanabadi bucks for breeding purpose. On the other hand, the semen parameters should consider only after 8.5 to 9 months of age for selection of Osmanabadi bucks for breeding.

  相似文献   
104.
105.
Nutrition is a critical component of equine health. Horse owners' knowledge of nutrition is likely to affect their feeding practices. The aim of this study was to survey feeding practices, dietary supplement use, and knowledge about equine nutrition in New England by surveying a subpopulation of horse owners (67/337 or 19.8%) who brought their horses to the Large Animal Hospital at the Cummings School of Veterinary Medicine at Tufts University between July and September 2008. All owners reported feeding hay, with the majority feeding grass or timothy hay. Most owners (96%) reported feeding a concentrate in addition to hay. Approximately 84% of owners reported including at least one dietary supplement in their horse's daily feeding. The most commonly used supplements were chondroprotectives, electrolytes, and multivitamins. Survey questions designed to assess the owner's knowledge of nutrition suggested that many owners may not have a basic understanding of principles of equine nutrition; less than 50% knew the daily water and hay requirements for a horse, and 69% lacked knowledge about the proper use of concentrates in a diet. Most of the surveyed owners consulted multiple sources of information concerning equine nutrition, including veterinarians (n = 36), trainers (n = 27), feed stores (n = 10), and the internet (n = 7). Although the major source of information was the veterinarian, it appears that the communication between horse owners and their veterinarian about optimal feeding practices could be enhanced. This survey demonstrated areas in the veterinarian–client dialog that need to be addressed when evaluating the health and well-being of the horse.  相似文献   
106.
Sida cordifolia L., Croton bonplandianum L., Malachra capitata L., Eclipta prostrata L., Clerodendron inerme L., Acalypha indica L., and Urena lobata L. are common weeds found all over India. They are often infected by different begomovirus complexes and may act as reservoirs of crop-infecting begomoviruses. Cloning and sequencing were done to partially characterize the begomovirus complexes associated with these weed species from the eastern part of India and their genetic pattern was compared with respective geographical isolates throughout India. Coat protein (CP) genes were found to be amplified from all the infected samples tested in this study, whereas betasatellite molecules amplified only from four infected samples (Sida, Croton, Malachra and Urena). Sequence analysis using CP genes and betasatellites of the present begomovirus complexes showed significant variation among their geographical isolates and also exhibited closeness to different crop-infecting begomovirus complexes. The majority of the weed-infecting begomovirus complexes characterized in this paper are reported for the first time from India.  相似文献   
107.
108.
109.
Cotton leaf curl virus (CLCuV) (Geminiviridae : Begomovirus), the causative agent of leaf curl disease in cotton plants (Gossypium hirsutum), is exclusively transmitted by whitefly species Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). CLCuV transmission occurs in Sriganganagar (Rajasthan), an area endemic with cotton leaf curl disease. The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. To further understand these relationships, fecundity and life history parameters of an indigenous non- b (Asia II genetic group) biotype whitefly, B. tabaci, were compared on 10, 25, and 40 days post-inoculation (DPI), in CLCuV-infected and healthy cotton plants to determine the effect of virus on its vector. The development time of the immature stages of whiteflies was significantly reduced on CLCuV-infected plants. The development time of the immature stages did not change with severity of symptoms at 25 and 40 DPI (45- and 60-d-old plants). Cotton leaf curl virus infection increased percent egg viability of B. tabaci. Whiteflies deposited significantly fewer eggs on virus-infected plants than on healthy plants. Whiteflies had better egg viability on younger plants than older plants, whereas plant age did not affect the fecundity. Male and female whiteflies had shorter longevity on CLCuV-infected plants than on healthy plants.  相似文献   
110.
The aim of this study was to characterize the distribution of oestrogen receptor (ER)α and ERβ as well as both progesterone receptors isoforms progesterone receptor (PR) A and PRB in the luminal and glandular epithelia and stroma of the endometrium during the different phases of the follicular wave in llamas. Six llamas were examined by transrectal ultrasonography, and a transcervical biopsy was obtained when a follicle at the growing, plateau and regressing phase was recorded. Blood samples were collected at the time of biopsy for hormone determinations. An immunohistochemical technique was used to study receptor populations. Total positive area was evaluated in the different cell types by Image Analysis. Mean diameter measurements of the largest follicle were 6.9, 8.5 and 5.1 mm (p < 0.001) and mean plasma oestradiol‐17β concentrations were 27.9 ± 3.26; 30.0 ± 2.79 and 24.0 ± 1.78 pmol/l (p = 0.32) during the growing, plateau and regressing phases, respectively. Immunostaining of ERα was higher in the luminal epithelium during the plateau and regressing phases (p < 0.05) than during the growing phase. More positive cells to ERβ were observed in the glandular epithelium of the growing and plateau phases (p < 0.05) than during the regressing phase. A higher percentage of cells positive to PRB was recorded in the luminal and glandular epithelia during the plateau phase (p < 0.05), while the PRA immunostaining was similar among phases. In brief, this study showed an increased population of ERα and PRB in the luminal epithelium, and only of PRB in the glandular epithelium at the time when an ovulatory follicle is present. The physiological importance of these changes in llamas remains to be elucidated.  相似文献   
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