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1.
Krishna Mohan Vijay Kumar Mihir Sarkar B. S. Prakash 《Tropical animal health and production》2010,42(1):21-26
The objective of this study were (1) to establish the duration of behavioral estrus signs and timing of ovulation in Murrah
buffaloes (n = 10) and (2) to determine relationship between behavioral estrus signs with change in plasma estrogen concentrations.
Estrus and its behavioral signs were detected at hourly intervals by visual observations, per recta examination of genitalia
and bull parading four times in a day for 30 minutes each. Among the behavioral signs of estrus, swollen vulva (80%) was the
best indicator of estrus followed by excitement (70%). Among the duration of behavioral estrus signs the first and longest
duration of estrus signs was swollen vulva which was seen upto 19.8 ± 0.8 h after onset of estrus. The mean total duration
of estrus symptoms from appearance to disappearance of all the behavioral estrus symptoms was 23.5 ± 1.7 h. All the behavioral
estrus symptoms were observed during the period of estrogen surge. Endocrine profile during the periestrus period showed that
the mean peak concentrations of total estrogen 23.9 ± 3.9 pg/ml occurred at 8.8 ± 1.7 h after onset of estrus. The average
number of estrus symptoms observed per animal during onset of spontaneous estrus was 5.7. Ovulation occurred after 37.4 ± 1.7 h
after onset of estrus and 13.4 ± 1.0 h after end of total estrogen surge respectively. In conclusion, our results suggest
that all signs of behavioral estrus occurred during the preovulatory rise in estrogens. The first sign of estrus to be observed
was a swollen vulva and this symptom persisted the longest. 相似文献
2.
Kumar V Kumar P Mohan K Sarkar M Suresh KP Chauhan MS Prakash BS 《Tropical animal health and production》2011,43(3):669-674
The objective of this study was to elucidate the changes in circulating levels of plasma interleukin-8 (IL-8) during peripartum
period in Murrah buffaloes (Bubalus bubalis). IL-8 was estimated in blood plasma of healthy peripartum Murrah buffaloes (n = 6) on days ±30, ±15, ±5, ±3, ±1 and 0 pre- and postpartum with respect to the day of parturition (day 0) in each of the
two different seasons (hot–humid and spring). The mean microclimate Temperature–Humidity Index (THI) during spring season
was significantly lower (p < 0.01) than the corresponding THI in hot–humid season. In both the seasons, plasma IL-8 remained lower in prepartum period
(≤46.56 ± 14.08 pg/ml during spring and ≤ 73.18 ± 18.56 pg/ml during hot–humid season) than in the postpartum period (≥51.41 ± 13.82 pg/ml
during spring and ≥ 84.13 ± 16.97 pg/ml in hot humid season). During spring, the IL-8 levels were significantly higher (P < 0.05) on days +5 and +15 postpartum in comparison to the IL-8 levels on days −30, −5, and −3 prepartum. During hot–humid
season, IL-8 level was significantly higher (P < 0.05) on day +30 as compared to the IL-8 levels on days −30 and −5 prepartum. The correlation between IL-8 and mean microclimate
THI was significant (r = 0.25, P < 0.01). From the results, it is concluded that peripartum period in buffaloes is associated with an inflammatory response
leading to significantly higher plasma IL-8 during parturition and postpartum period than in the pre-partum period. 相似文献
3.
Rawther SS Saseendranath MR Nair GP Tresamol PV Pillai UN Abraham J Senthilkumar TM Nagalakshmy S Nimisha KK 《Tropical animal health and production》2012,44(4):911-914
In the present study efficacy of single intradermal Johnin test, acid fast staining of faecal smear and IS 900 faecal polymerase chain reaction tests was evaluated in 200 goats for detection of Mycobacterium avium subsp paratuberculosis. Two hundred goats comprising 150 goats from an organised farm in Trichur district and 50 goats reared under field condition
at farmers premise from Malappuram district of Kerala state formed the study population. Faecal smear from all the 200 goats
was stained by Ziehl–Neelsen acid fast stain and faecal polymerase chain reaction (PCR) specific for M. avium subsp paratuberculosis (MAP); IS 900 was performed on all samples. All the animals were subjected to single intradermal Johnin test. Out of 200 goats screened
for paratuberculosis, six goats (3%), 11 goats (5.5%) and 42 goats (21%) were found positive by Ziehl–Neelsen acid fast staining
of faecal smear, single intradermal Johnin test and IS 900 PCR respectively. Results of the present study indicate that amplification of IS 900 insertion element was the most specific and sensitive diagnostic detection method. Single intradermal Johnin test and Ziehl–Neelsen
acid fast staining did not show any significant difference. 相似文献
4.
Laura C. Falzon Paula I. Menzies John VanLeeuwen Krishna P. Shakya Andria Jones-Bitton Jacob Avula Jocelyn T. Jansen Andrew S. Peregrine 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(8):749-756
This study investigated the overwintering survival and infectivity of free-living gastrointestinal nematode (GIN) stages on pasture. The presence of GIN larvae was assessed on 3 sheep farms in Ontario with a reported history of clinical haemonchosis, by collecting monthly pasture samples over the winter months of 2009/2010. The infectivity of GIN larvae on spring pastures was evaluated using 16 tracer lambs. Air and soil temperature and moisture were recorded hourly. Free-living stages of Trichostrongylus spp. and Nematodirus spp. were isolated from herbage samples. Gastrointestinal nematodes were recovered from all tracer lambs on all farms; Teladorsagia sp. was the predominant species. Very low levels of Haemonchus contortus were recovered from 1 animal on 1 farm. The results suggest that Haemonchus larvae do not survive well on pasture, while Teladorsagia sp., Trichostrongylus spp. and Nematodirus spp. are able to overwinter on pasture in Ontario and are still infective for sheep in the spring. 相似文献
5.
Yadav Sudhir Mondal Manoranjan K. Shew Aaron Jagadish S. V. Krishna Khan Zahirul Haque Sutradhar Asish Bhandari Humnath Humphreys Elizabeth Bhattacharya Jayanta Parvin Rokhsana Rahman Mahabubur Chandna Parvesh 《Paddy and Water Environment》2020,18(2):331-343
Paddy and Water Environment - Most of the lands of the southern coastal zone of Bangladesh are protected from tidal flooding and storm surges by embankments constructed during the 1960s and 1970s,... 相似文献
6.
Renu Pandey Krishna Kant Dubey Altaf Ahmad Rakshanda Nilofar Rachana Verma Vanita Jain 《Journal of plant nutrition》2015,38(8):1196-1217
Cultivars of Triticum aestivum, T. durum, and Secale cereale were grown at low (2 μM) and sufficient (500 μM) phosphorus (P) under ambient carbon dioxide (380 μmol mol?1; aCO2) and elevated CO2 (700 μmol mol?1, eCO2) to study responses of cereal species in terms of growth and P utilization efficiency (PUE) under P x CO2 interaction. Dry matter accumulation increased under eCO2 with sufficient P. Nevertheless, dry matter accumulated at eCO2 with low-P was similar to that obtained at aCO2 with sufficient P. Leaf area was 43% higher under eCO2 with sufficient P. Significant increase in lateral root density, length and surface area were noted at low-P under eCO2. Phosphorus use efficience (PUE) increased by 59% in response to eCO2 in low-P plants. Thus, eCO2 can partly compensate effect of low-P supply because of improved utilization efficiency. Among cereals, durum wheat was more suitable in terms of PUE under high CO2 and limiting P supply. 相似文献
7.
8.
Sabyasachi Banerjee Seema Singh Shailesh Pandey Maneesh S. Bhandari Amit Pandey Krishna Giri 《Forest Pathology》2020,50(2)
Wilt disease caused by Fusarium solani is a serious constraint to Dalbergia sissoo (shisham) plantations in northern India. In this study, the antagonistic potential of 40 bacterial isolates recovered from rhizophere soil of healthy shisham trees, and a well‐characterized Trichoderma species (Trichoderma virens) were tested for their possibility as biocontrol agents for F. solani. Two promising isolates (S1 and S15) were identified which inhibited pathogen growth, caused chitin degradation, produced siderophores and solubilized phosphate in vitro. Isolate S15 scored highest for hydrogen cyanide (HCN) production while isolate S1 was a non‐HCN producer. These two isolates were identified as Serratia marcescens (S1) and Pseudomonas azotoformans (S15) following sequence analysis of 16S rDNA. In dual culture assays, T. virens caused 80% inhibition of mycelial growth of the test fungus. The three selected antagonists when tested in planta in the glasshouse completely suppressed production of wilt symptoms on 12‐month‐old shisham plants. Further work is needed to ascertain the potential of these isolates to be used as biocontrol agents to manage shisham wilt under field conditions. 相似文献
9.
Zaluzanin D, a sesquiterpene lactone has been isolated from the aerial parts of Vernonia arborea as a major constituent (0.04%). Antifungal activity of zaluzanin D has been studied against six plant-pathogenic fungi. 相似文献
10.
Collective action by local communities has been recognised as crucial for effective management of natural resources, particularly
the management of forests in rural settings in developing countries. However, the processes and outcomes of collective action
in forest management are often analysed through a narrow rational choice model, ignoring the impacts of wider social, political
and economic processes in conditioning peoples’ decisions to act (or not to act) collectively. Optimistic assumptions are
made for collective action being instrumental to enhance both social and ecological outcomes, but there is a paucity of empirical
evidence on how and why the condition of forests has improved (or deteriorated) under collective action, and what impacts
the change in forest condition has on various groups within local communities. This study critically examines the emergence,
evolution and outcomes of collective action in a case of community forestry in Nepal. A mix of qualitative and quantitative
methods has been used to collect primary data from the forest, households, key informants and focus groups. The emergence
and outcomes of collective action is found to be embedded in social, economic and political relationships, where powerful
actors control the use of forests in order to ensure conservation, thereby resulting in the underutilisation of forest products.
Poor users, who depend heavily on forests, are found to be worse off economically under community forestry, but still engage
in collective action for a variety of socio-political reasons. This contradicts the conventional wisdom which assumes that
people only cooperate when they benefit from cooperation. It is concluded that a deeper understanding of the embeddedness
of community forestry is needed in order to achieve the potential of collective action.
相似文献
Krishna K. ShresthaEmail: |