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991.
The aim of this work was to evaluate the effect of quebracho tannins extract (QTE) on feed intake, dry matter (DM) digestibility, and methane (CH4) emissions in cattle fed low-quality Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 295 ± 19 kg were allotted to five treatments (0, 1, 2, 3, and 4% QTE/kg DM) in a 5 × 5 Latin square design. Intake, digestibility, and total methane emissions (L/day) were recorded for periods of 23 h when cattle were housed in open-circuit respiration chambers. Dry matter intake (DMI), organic matter intake (OMI), dry matter digestibility (DMD), and organic matter digestibility (OMD) were different between treatments with 0 and 4% of QTE/kg DM (P < 0.05). Total volatile fatty acid and the molar proportion of acetate in the rumen was not affected (P < 0.05); however, the molar proportion of propionate increased linearly (P < 0.01) for treatments with 3 and 4% QTE. Total CH4 production decreased linearly (P < 0.01) as QTE increased in the diet, particularly with 3 and 4% concentration. When expressed as DMI and OMI by CH4, production (L/kg) was different between treatments with 0 vs 3 and 4% QTE (P < 0.05). It is concluded that the addition of QTE at 2 or 3% of dry matter ration can decrease methane production up to 29 and 41%, respectively, without significantly compromising feed intake and nutrients digestibility.  相似文献   
992.
Brucellosis is a zoonotic disease worldwide distributed and having the economic as well as public health importance. The prevalence of brucellosis among sheep flock having history of abortions was studied. A total of 229 samples comprising of 157 blood and 72 clinical samples (vaginal swabs) were collected from 157 animals. Clinical samples were processed for the isolation of Brucella melitensis. Serum samples (n = 157) were tested by Rose Bengal plate test (RBPT) and i-ELISA. A total of 68 (43.31%) and 104 (66.24%) samples were positive by RBPT and ELISA, respectively. Brucella isolates (n = 2) were recovered from clinical samples. Both isolates demonstrated amplification for bcsp 31 and IS711 genes. On AMOS PCR, both the isolates amplified at 731 bp, i.e., belongs to B. melitensis species. The incidence of B. melitensis in a migratory flock warns the thorough testing and culling of Brucella-infected sheep from the flock on a continuous basis; otherwise, such incidence will be routine and poor farmers will be at a loss.  相似文献   
993.
The aim of this project is to study the clinical signs and lesion of velogenic Newcastle disease (vND) in commercial turkeys, and also to find out if La Sota vaccination offered protection against these signs and lesions. The cockerels were included as positive controls. One hundred and twenty turkey poults and cockerels were divided into eight groups as follows: unvaccinated unchallenged turkeys (UUT), unvaccinated challenged turkeys (UCT), vaccinated unchallenged turkeys (VUT), vaccinated challenged turkeys (VCT), and along the same lines, the cockerel groups were UUC, UCC, VUC and vaccinated challenged cockerels (VCC). Vaccination was at 3 weeks of age while challenge was at 6 weeks of age. The unvaccinated turkeys and cockerels (UCT and UCC) showed different degrees of depression, diarrhoea and later paralysis at challenge. Total mortality was 100% in cockerels within 6 days, but 60% in turkeys. Similar but milder clinical signs were found in the VCC with a total mortality of 13.3%. The VCT showed mild drop in feed and water consumption, and no mortality. All the challenged groups had significant (p < 0.05) loss of weight when compared with their controls. Necropsy showed that while the UCC had severe proventricular haemorrhages, intestinal and caecal tonsil ulcers, the UCT had no digestive tract lesion. There was severe atrophy of the lymphoid organs in all the challenged groups. Histopathological sections of the bursa, spleen and thymus in all the challenged groups with special emphasis on the vaccinated and unvaccinated turkeys with mortalities of 0 and 60%, respectively, had very severe necrosis and depletion of the lymphoid tissue. Virus was isolated from the cloacal swabs. The haemagglutination inhibition antibodies were significantly higher (p < 0.05) in the challenged groups than the unchallenged. The above observations in the intestinal tracts of UCT are of diagnostic significance while the gross and microscopic lesions in the UCT and VCT show that La Sota vaccination may not protect turkeys against the destruction of the lymphoid organs by vND as earlier reported in chickens. This may lead to immunosuppression and production problems in areas where vND is enzootic.  相似文献   
994.
Zimbabwe’s smallholder dairying faces many challenges that affect the welfare of dairy cows; however, the status of this welfare has not yet been determined. A cross-sectional study was conducted in Midlands Province on 41 active smallholder dairy farms with 86 cows in winter and summer to determine the risk factors and indicators to impaired cow welfare. These objectives were achieved using farmer questionnaires and direct observations. Eleven percent of the observed cows were severely lame in summer while only 5% were severely lame in winter. Lameness was significantly associated with season, absence of shade, breed, and low dipping frequency; 58% of the cows had low body condition scores (BC?<?3) and this low BC was associated with low frequency of protein (p?=?0.002) and vitamin (p?=?0.012) supplementation recorded in more than 52% of the farms visited. In winter, only 11% of the observed cows were heavily soiled (score 3), while in summer 64% of the cows were heavily soiled and this was associated with slurry accumulation in more than 80% of the observed cattle pens as well as the study season (p?<?0.001). A quarter (26%) of the studied animals had visible teat lesions on the teat skin and this was associated with the type of lubricant used (p?=?0.011). Only 34% of the cows allowed an approaching stockman to touch them and this was associated with shouting (p?=?0.012) and whipping of cows (p?=?0.002). The study concluded that welfare of dairy cows was poor in most of the smallholder dairy farms studied.  相似文献   
995.
The dual-purpose bovine system represents 98.4% of the bovine livestock of Veracruz, the main cattle-producing state of Mexico. This system supplies calves to meat companies, a sector in which Veracruz has been the national leader in the last decade. The objective of the present study was to analyze the effect of the altitudinal zonation of farms on livestock technology and productivity in a microbasin of the Gulf of Mexico where small farms predominate. Structured interviews were applied to producers located in three altitudinal zones (at average altitudes of 50, 140, and 450 m, respectively, for lower, middle, and upper zones). Sample size was 135 farms having similar land surface (within a range of 15–22 ha). The results indicated multiple differences among farms located in the three zones. Farms in the middle and lower zones presented higher productive indicators than those in the upper zone. Differences in herd structure and management resulted in important differences in productivity, income, and profits in milk and calf production. We concluded from this study that altitudinal zonation in Veracruz had a clear effect on the differentiation of small farms, which are representative of dual-purpose cattle. The upper zone performs cattle activity under conditions with greater disadvantages in the analyzed region.  相似文献   
996.
AIM: To develop and validate a simple and sensitive method using liquid chromatography-mass spectrometry (LC-MS) for quantification of articaine, and its major metabolite articainic acid, in plasma of red deer (Cervus elaphus), and to investigate the pharmacokinetics of articaine hydrochloride and articainic acid in red deer following S/C administration of articaine hydrochloride as a complete ring block around the antler pedicle.

METHODS: The LC-MS method was validated by determining linearity, sensitivity, recovery, carry-over and repeatability. Articaine hydrochloride (40?mg/mL) was administered S/C to six healthy male red deer, at a dose of 1?mL/cm of pedicle circumference, as a complete ring block around the base of each antler. Blood samples were collected at various times over the following 12 hours. Concentrations in plasma of articaine and articainic acid were quantified using the validated LC-MS method. Pharmacokinetic parameters of articaine and articainic acid were estimated using non-compartmental analysis.

RESULTS: Calibration curves were linear for both articaine and articainic acid. The limits of quantifications for articaine and articainic acid were 5 and 10?ng/mL, respectively. Extraction recoveries were >72% for articaine and >68% for articainic acid. After S/C administration as a ring block around the base of each antler, mean maximum concentrations in plasma (Cmax) of articaine were 1,013.9 (SD 510.1) ng/mL, detected at 0.17 (SD 0.00) hours, and the Cmax for articainic acid was 762.6 (SD 95.4) ng/mL at 0.50 (SD 0.00) hours. The elimination half-lives of articaine hydrochloride and articainic acid were 1.12 (SD 0.17) and 0.90 (SD 0.07) hours, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The LC-MS method used for the quantification of articaine and its metabolite articainic acid in the plasma of red deer was simple, accurate and sensitive. Articaine hydrochloride was rapidly absorbed, hydrolysed to its inactive metabolite articainic acid, and eliminated following S/C administration as a ring block in red deer. These favourable pharmacokinetic properties suggest that articaine hydrochloride should be tested for efficacy as a local anaesthetic in red deer for removal of velvet antlers. Further studies to evaluate the safety and residues of articaine hydrochloride and articainic acid are required before articaine can be recommended for use as a local anaesthetic for this purpose.  相似文献   
997.
Xylitol is commonly used as sugar substitute in households. While it has numerous beneficial effects on human health, it is highly toxic to dogs. The goal of this study was to examine whether xylitol has similar deleterious effects, such as hypoglycaemia and acute hepatic failure, on cats. Our research included six healthy middle‐aged cats. Xylitol was dissolved in deionized water and administered p.o. at three doses (100, 500 and 1,000 mg/kg body weight). These dosages have been considered toxic and can cause liver failure or even death in dogs. After every xylitol administration, the basic health status and the blood glucose of cats were observed regularly. Additionally, prior to and 6, 24 and 72 hr after xylitol administration, blood samples were taken to check complete blood count, clinical biochemical parameters and enzymes such as ALT, ALKP, GGT, GLDH, bile acids, BUN, creatinine, phosphate, total protein, albumin, sodium and potassium. There were no significant changes (> .05) in any of the haematological or biochemical parameters. Blood glucose concentrations did not show any significant alterations, except at 1,000 mg/kg dose, where a mild but significant increase was observed, but it was in physiological range. Based on our results, xylitol did not induce toxic effects on cats.  相似文献   
998.
Monepantel (MNP) is a novel anthelmintic compound launched into the veterinary pharmaceutical market. MNP is not licenced for use in dairy animals due to the prolonged elimination of its metabolite monepantel sulphone (MNPSO2) into milk. The goal of this study was to evaluate the presence of potential in vivo drug‐drug interactions affecting the pattern of milk excretion after the coadministration of the anthelmintics MNP and oxfendazole (OFZ) to lactating dairy cows. The concentrations of both parent drugs and their metabolites were measured in plasma and milk samples by HPLC. MNPSO2 was the main metabolite recovered from plasma and milk after oral administration of MNP. A high distribution of MNPSO2 into milk was observed. The milk‐to‐plasma ratio (M/P ratio) for this metabolite was equal to 6.75. Conversely, the M/P ratio of OFZ was 1.26. Plasma concentration profiles of MNP and MNPSO2 were not modified in the presence of OFZ. The pattern of MNPSO2 excretion into milk was also unchanged in animals receiving MNP plus OFZ. The percentage of the total administered dose recovered from milk was 0.09 ± 0.04% (MNP) and 2.79 ± 1.54% (MNPSO2) after the administration of MNP alone and 0.06 ± 0.04% (MNP) and 2.34 ± 1.38% (MNPSO2) after the combined treatment. The presence of MNP did not alter the plasma and milk disposition kinetics of OFZ. The concentrations of the metabolite fenbendazole sulphone tended to be slightly higher in the coadministered group. Although from a pharmacodynamic point of view the coadministration of MNP and OFZ may be a useful tool, the presence of OFZ did not modify the in vivo pharmacokinetic behaviour of MNP and therefore did not result in reduced milk concentrations of MNPSO2.  相似文献   
999.
1000.
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