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991.
992.
The present investigation was carried out to assess the trace mineral profile in blood and hair from cows environmentally exposed to lead and cadmium and to examine if these toxic heavy metals in blood and hair could affect blood copper, cobalt, zinc and iron concentrations and their accumulation in hair. Respective blood and tail hair samples were collected from adult cows above 3 years, reared in different industrial localities. Samples were also collected from urban areas with small industrial units (n = 55) and areas supposed to be free from pollution. The concomitant exposure of animals to both the heavy metal pollutants was not recorded in either of the industrial or urban locality. Blood lead was significantly (P < 0.01) correlated with blood copper (r = -0.339), cobalt (r = -0.224) and iron (r = -0.497). The increasing blood lead concentrations, irrespective of area of collection of samples, was associated with declining blood copper and iron, and cows with blood lead level above 0.60 mug/ml had significantly (P < 0.05) lower blood copper and iron. The higher blood lead but not cadmium significantly influenced the accumulation of lead (r = 0.323, P < 0.01) and cadmium (r = 0.204, P < 0.01) in hair possibly leading to significantly (P < 0.05) higher accumulation of both lead and cadmium in hair from cattle around lead-zinc smelters and closed lead-cum-operational zinc smelter, where blood cadmium level was comparable with that from unpolluted area. Concentration of zinc (r = 0.237, P < 0.01) and iron (r = 0.183, P < 0.01) but not copper and cobalt in tail hair was significantly influenced by their respective blood concentration. Both the hair lead and cadmium had a significant (P < 0.01) positive correlation with hair copper (r = 0.234, 0.294), zinc (r = 0.489, 0.775), and iron (r = 0.385, 0.643) concentrations. Thus, it is concluded from the present study that the higher blood lead concentrations in cattle irrespective of locality/industrial operations areas affected trace elements profile in blood and hair.  相似文献   
993.
The current study was aimed to establish the impact of progesterone supplementation (norgestomet progestagen) between days 4 to 10 post-ovulation on subsequent luteal profile and conception rate in buffaloes. The 28 Murrah buffaloes of second to fourth parity, having normal reproductive organs, were estrus synchronized by double PGF protocol at 11 days apart. The buffaloes were inseminated during mid- to late estrus and thereafter repeated at 24 h interval. The buffaloes were randomly assigned into two groups: (1) control (no treatment, n?=?14) and (2) treatment group (CRESTAR ear implant, n?=?14). The CRESTAR ear implant (3 mg, norgestomet progestagen) was inserted subcutaneous between days 4 to 10 post-ovulation. The ovaries were scanned at estrus and thereafter on days 4, 10, 16, 21, and 40 post-ovulation to examine the preovulatory follicle (POF) and corpus luteum (CL) diameter. Each ultasonography was followed by blood sample collection for analysis of plasma progesterone concentrations following ovulation. The conception rate was similar (p?>?0.05) between treated and control buffaloes. The pregnant buffalo of the control group had larger (p?<?0.05) POF diameter than nonpregnant counterparts. The CL diameter was similar (p?>?0.05) in both treated and untreated control as well as in their pregnant and nonpregnant buffaloes of the respective groups. The plasma progesterone concentrations were higher (p?<?0.05) in the treatment group on the day 10 post-ovulation as compared to the control buffaloes. It is concluded that norgestomet supplementation had no impact on conception rate and CL diameter but enhances the plasma progesterone concentrations following treatment in buffaloes.  相似文献   
994.
This study investigated the apoptosis-like events associated with cryopreservation process and their relationship with cryocapacitation in buffalo (Bubalus bubalis) sperm. A total of 49 semen ejaculates from seven bulls were studied for structural changes in sperm following cryopreservation. Apoptotic changes were detected by assays specific for translocation of phosphatidylserine (PS) to the cell surface, alterations in membrane permeability and mitochondrial membrane potential (MMP), and DNA integrity. A significant (p < 0.01) percentage of cryopreserved sperm showed externalization of PS and early apoptotic changes and lowered MMP when compared with the fresh sperm. Freezing and thawing of sperm increased permeability to YOPRO-1, an impermeant fluorescent dye. However, on TUNEL staining, cryopreserved sperm showed no breach in DNA integrity. The sperm capacitation status was evaluated by chlortetracycline (CTC) fluorescence pattern, in which a significant (p < 0.01) percentage of cryopreserved sperm were found to be capacitated. The capacitated sperm (Pattern B) was positively correlated with the aforementioned apoptotic events. In conclusion, cryopreservation process induced early apoptosis-like changes in buffalo sperm, and a close link exists between cryocapacitation and apoptosis during cryopreservation of sperm.  相似文献   
995.
Classical swine fever (CSF), a highly contagious viral disease of pigs, is endemic in India. As there is no information concerning the accurate genetic typing of classical swine fever virus (CSFV) isolates in India, 16 CSF viruses isolated during 2005-2007 from domestic pigs in different districts of Assam were typed in 5′ UTR (150 nucleotides). To confirm the genetic typing results and to study the genetic variability, selected viruses were also analyzed in E2 (190 nt) and NS5B gene (409 nt) regions. Phylogenetic analysis revealed that all the 16 CSFV isolates analyzed belonged to group 1 and subgroup 1.1 in contrast to the situation in other Asian countries. Additionally, analysis in E2 and NS5B region placed the Indian isolates in a clearly separated clade within subgroup 1.1. The results suggest that subgroup 1.1 CSF viruses are currently circulating in India, which is important for epidemiology and control of CSF.  相似文献   
996.
In this study we present the first report on partial amplification, sequencing and phylogenetic relationship of VP2 of the Indian isolate BTV-2. A PCR product of 1135 bp was amplified, cloned and sequenced. About 1063 bp of partial VP2 gene (1792-2854 bp region) of the Indian isolate was subjected to sequence analysis with already published sequences available in the genome database. The percent similarity of 85.2 was observed with Taiwan isolate and 59% with other isolates of BTV-2. However, 46.2% similarity with Australian BTV-1 and no significant similarity were noted with other serotypes. In-silico analysis and restriction enzyme digestion confirmed the presence of conserved SalI site at 2380 bp position in both Indian and Taiwan isolates. Phylogenetic analysis showed that all BTV-2 isolates formed one distinct group in which BTV-2 Indian and Taiwan isolate is more closely related and further demonstrated that BTV’s of the same serotype from different geographical regions were closely related at nucleotide and amino acid level, respectively.  相似文献   
997.
998.

In the hot semi-arid tropical region, extreme summer is a major constraint in sheep production. The growth performance of growing lambs is impaired during the summer. Therefore, the present study was conducted to assess the effect of protection against hot climate on growth performance, physiological response, and endocrine profile of growing lambs under semi-arid tropical environment. All the data in the experiment were presented as mean ± SE. Thirty Malpura lambs with the age of 122.7 ± 6.05 days and body weight of 19.52 ± 0.42 kg were allotted into three groups, viz. G1 (control, lambs kept in open area under tree shade), G2 (lambs kept in conventional asbestos-roofed shed), and G3 (lambs kept in designed shed). The allotment was based on their initial body weight so that the mean body weight of each group was similar. In all three types of protection, lambs were provided with sufficient space to move and social interaction. In asbestos-roofed shed (G2), all the four sides from ground to the roof were fenced with strong galvanized iron chain link. But in G3, all the four sides were constructed in a manner that there was 0.13 m air space between inner and outer solid brick columns of the wall up to 1.37 m height, and rest up to the roof was fenced with bamboo splint net. The air space between the two columns of the wall was filled with sand, and it was kept in moist condition by continuous water drips which provide extra evaporative cooling. The designed shed was basically constructed with bamboo. Tree shade was assured under the natural shades of large trees. The shaded area was protected by wire fences. The experiment was conducted for 45 days during very high temperature (May–June). The lambs were provided with ad libitum green fodder, dry roughage, 300 g concentrate, and ad libitum drinking water. The respiration rate at morning and afternoon, pulse rate at morning and afternoon and rectal temperature at afternoon was significantly (P < 0.05) lower in lambs of G3 as compared to other groups. The final body weight did not differ significantly between the groups, but average daily gain (g/day) was higher in G3 (150.06 ± 11.13) as compared to the G1 (109.69 ± 18.10). The feed conversion rate (FCR) was significantly (P < 0.05) better in G3 (5.49 ± 0.08) as compared to G1 (7.65 ± 0.08) and G2 (6.60 ± 0.08). The hemoglobin level was significantly (P < 0.05) higher in G1. The endocrine profile did not vary significantly (P > 0.05) among the groups, but insulin-like growth factor-1 (IGF-1) was higher in G3. It can be concluded from this study the lambs provided with better protection during summer remained in more comfortable condition, showed better FCR, and although not statistically significant showed better growth performance.

  相似文献   
999.
The influence of endotoxin on the disposition kinetics of oxytetracycline (OTC) (10 mg/kg) was investigated in five healthy ruminating male crossbred calves. The serum concentration-time data of OTC before and after endotoxin challenge were best described by a two-compartment open model. Repeated administration of Escherichia coli endotoxin (1 microg/kg, i.v.) at an interval of 12 h up to 48 h produced a clear rise in the body temperature and an increase in the pulse and respiration rates. Endotoxin caused a significant reduction in mean transit time in tissue compartment (MTTT) (P < or = 0.05), mean residence time in the peripheral tissue compartment (MRTT) (P < or = 0.05), mean residence time in the body (MRTB) (P < or = 0.05), elimination half-life (t1/2lambda2) (P < or = 0.05) and distribution space in tissues (VT) (P < or = 0.01) and at steady-state (Vd(ss)) (P < or = 0.01). Endotoxin had no effect on the distribution clearance (ClD), systemic clearance (Cl) and distribution half-life of OTC, while the values of first order rate constant of transfer of drug from tissue to central compartment (K21) and the zero time intercept at terminal phase (C2) were significantly high. The drug dosage regimens to maintain serum OTC concentrations of 0.5, 1, 2, 4, 6 and 8 microg/mL were also determined in febrile and clinically healthy animals.  相似文献   
1000.
Hydropericardium syndrome, an emerging disease of poultry, has recently been detected in some countries of Asia and America, particularly in broiler birds aged 3–6 weeks. The disease is characterized by its sudden occurrence with high mortality of up to 80% in broilers and low mortality of under 10% in layers, associated with hydropericardium. Its course is of 7–15 days under natural conditions. The causative agent is probably fowl adenovirus serotype 4, belonging to group I aviadenovirus genus of the family adenoviridae, which can be cultivated in primary cell cultures of chicken kidney and embryo liver cells. The transmission of disease occurs laterally by the oral–faecal route. The livers of affected birds show necrotic foci, and basophilic intranuclear inclusion bodies fill the entire enlarged nucleus of some of the hepatocytes. The disease can be diagnosed from its gross lesions, histopathological changes in the liver and by serological tests, such as agar gel diffusion, counter immunoelectrophoresis, indirect haemagglutination and ELISA. It has been brought under control by inactivated liver organ vaccines (0.25 ml/bird) or inactivated cell culture vaccines (103.5 LD50/bird) given by the subcutaneous route at 10–15 days of age. The vaccine is effective in the face of an outbreak and significantly reduces the mortality.  相似文献   
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