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121.
Tropical Animal Health and Production - This study aimed to evaluate the effect of a mixture of temperate and legume grasses with or without energy supplementation on the performance and feeding...  相似文献   
122.
This study aimed to evaluate the effect of pearl millet silage ammoniated with urea on lamb carcass characteristics and meat quality. Thirty‐two noncastrated crossbred lambs at 4–5 months of age, with an average initial body weight of 17.39 ± 2.16 kg, were distributed into four treatments in a randomized block experimental design with eight animals per treatment. Experimental diets were composed of pearl millet silage ammoniated with four levels of urea (0%, 2%, 4% and 6%, on dry matter basis (DM). Carcass conformation and fatness decreased linearly (< 0.05). Except for the fat content, the proximate composition was not influenced (< 0.05) by the diets. Meat lightness and yellowness increased linearly (< 0.05). There was no effect of diets (> 0.05) on cooking losses or shear force. The levels of oleic and erucic fatty acid levels in the meat decreased linearly (p < 0.05), whereas linoleic and eicosadienoic acids, polyunsaturated fatty acids, PUFA:SFA ratio and ω6 contents increased (< 0.05). Pearl millet silage ammoniated with urea allows for the production of good‐quality lamb meat, with greater concentrations of polyunsaturated fatty acids. However, lambs fed diets with pearl millet ammoniated with up to 6% lead to a reduction of carcass characteristics without significantly affecting loin‐eye area possibly associated with low palatability of the additive used. The lower acceptance of the silages with higher levels of urea is due to the ammonia retention in the material is attributed to the ammonization process. Thus, in spite of the benefits on lamb meat quality, it is suggested that the use of this additive in the ammonization of tropical forages be carried out with care, in limits of up to 6%.  相似文献   
123.
Conventional somatic cell nuclear transfer (SCNT) technique of in vitro production of cloned embryos involves use of costly and complicated micromanipulators. Handmade cloning (HMC) technique has been applied as efficient and cost‐effective alternative in many livestock species. The aim of the present study was to compare the efficiency of in vitro production and in vitro development of cloned sheep embryos by the two techniques. Cloned embryos were produced by conventional SCNT using micromanipulator apparatus and by HMC technique. Enucleation efficiency and efficiency of fusion with somatic cell (nucleus donor) were compared. Cleavage percentage was observed on day 2 of in vitro culture (IVC), and morula and blastocyst percentages were calculated on day 7 of IVC. Higher enucleation efficiency (96.98 ± 1.01 vs. 93.62 ± 1.03; p > .05) as well as fusion efficiency was obtained with HMC technique than with conventional SCNT (96.26 ± 1.34 vs. 92.63 ± 0.70, p < .05); 181 cloned sheep embryos were produced in vitro by conventional SCNT and 92 by HMC. Cleavage percentage observed on day 2 of in vitro culture was higher in HMC than SCNT (66.92 ± 3.72 vs. 55.97 ± 2.5, respectively, p < .05). Morula percentage obtained was higher in SCNT than HMC (44.12 ± 2.93 vs. 30.43 ± 6.79, respectively, p < .05), whereas blastocyst percentage obtained by HMC was higher (12.46 ± 4.96) than SCNT (5.31 ± 2.25; p > .05). It was inferred that HMC technique provides a cost‐effective and efficient method of in vitro production of cloned sheep embryos with a comparatively simpler technique with a possibility of automation. Efficiency of cloned embryo production could be improved further by propagating and standardizing this technique.  相似文献   
124.
This study was carried out to examine the changes in plasma concentrations of the Ca‐binding antimicrobial proteins S100A7 and S100A8 during pregnancy in dairy cows. Holstein Friesian cows (n = 19) were inseminated with Holstein Friesian semen. Blood was collected at days 30, 60, 90, 120, 150, 180, 210, 240 and 270 after insemination. Plasma was used for measuring the concentrations of S100A7 and S100A8. Both S100A7 and S100A8 concentrations showed similar patterns during gestation; they increased during the midgestation, between days 90 and 180, and then declined before calving. The findings indicated that plasma concentrations of S100A7 and S100A8 did not change significantly during pregnancy in cows. Further studies are required to determine the roles of S100A7 and S100A8 in physiological function during pregnancy in dairy cows.  相似文献   
125.
Paraguay has registered no human cases of rabies since 2004, and the last case in dogs, reported in 2009, was due to a variant maintained in the common vampire bat “Desmodus rotundus”. In 2014, a dog was diagnosed as positive for rabies with aggression towards a boy and all required measures of control were successfully adopted. Epidemiological investigation revealed that the dog was not vaccinated and had been attacked by a crab‐eating fox, “zorro” (Cerdocyon thous). The sample was diagnosed by the Official Veterinary Service of the Country and sent to the Center on Rabies Research from the University of São Paulo, Brazil, for antigenic and genetic characterization. A second sample from a dog positive for rabies in the same region in 2015 and 11 samples from a rabies outbreak from Asuncion in 1996 were also characterized. The antigenic profile of the samples, AgV2, was compatible with one of the variants maintained by dogs in Latin America. In genetic characterization, the samples segregated in the canine (domestic and wild species)‐related group in an independent subgroup that also included samples from Argentina. These results and the epidemiology of the case indicate that even with the control of rabies in domestic animals, the virus can still circulate in wildlife and may be transmitted to domestic animals and humans, demonstrating the importance of continuous and improved surveillance and control of rabies, including in wild species, to prevent outbreaks in controlled areas.  相似文献   
126.
AIMS: To investigate the effect of targeted resynchronisation of cows treated for non-observed oestrus before the planned start of mating (PSM), that were not detected in oestrus or pregnant 23 days after treatment (phantom cows), on the proportion pregnant at 42 days after PSM and the end of mating.

METHODS: Farm staff from eight herds in two regions of the South Island of New Zealand identified 1,819 cows not showing oestrus by 10 days before PSM. These cows were treated with intravaginal progesterone for 7 days, and I/M gonadorelin 10 days and 1 day before PSM. Three days before PSM they were injected with cloprostenol and equine chorionic gonadotrophin, with fixed time artificial insemination (FTAI) at PSM. By 23 days after PSM, 1,218 cows had not returned to oestrus. Of these, 161 cows confirmed not pregnant by transrectal ultrasonography were randomly assigned to no treatment (control group; n=74) or were resynchronised 25 days after PSM using the same treatment programme as above, with FTAI 35 days after PSM (n=87). All cows that returned to oestrus were artificially inseminated until 42 days after PSM, when natural mating was used. All cows were examined using transrectal ultrasonography 80 to 90 days after PSM to confirm conception dates.

RESULTS: Of the 1,819 anoestrous cows treated before PSM, 526 (29 (95% CI=23.1–34.0)%) had not been observed in oestrus by 23 days after PSM and had not conceived, so were diagnosed as phantoms cows. For resynchronised cows, 42/87 (48 (95% CI=37.8–58.8)%) were pregnant by 42 days after PSM compared to 21/74 (28 (95% CI=18.1–38.7)%) control cows (p=0.009). At the end of mating 58/87 (67 (95% CI=56.6–76.7)%) cows in the resynchronised group were pregnant and 46/74 (62 (95% CI=50.9–73.2)%) in the control group (p=0.554). The hazard of conception from 21 to 42 days after PSM was 1.9 (95% CI=1.07–3.12) times greater for resynchronised than control cows (p=0.026).

CONCLUSION: In cows not observed in oestrus and treated before PSM, resynchronisation increased the proportion pregnant by 42 days after PSM.

CLINICAL RELEVANCE: The benefit of resynchronisation depends on the number of anoestrous cows before PSM and the number of phantom cows after PSM. However at the herd-level it is likely that providing advice to reduce the known risk factors for cows not being observed in oestrus before the PSM may well be more cost effective than identifying and treating a sub-population of phantom cows.  相似文献   

127.
Lead (Pb) poisoning of cattle has been relatively common in Australia and sump oil has been identified as an important cause of Pb toxicity for cattle because they seem to have a tendency to drink it. Lead-free petrol has been available in Australia since 1975, so the aim of this study was to assess the current risk to cattle from drinking used automotive oils. Sump or gear box oil was collected from 56 vehicles being serviced. The low levels of Pb found suggest that the removal of leaded petrol from the Australian market as a public health measure has benefited cattle by eliminating the risk of acute poisoning from used engine oil.  相似文献   
128.
红外光谱法作为一种新的研究手段已经广泛应用于土壤分析,由其检测区域和手段的不同又可分为多种光谱类 型。本研究以第四纪黄土为例,系统地比较了近红外区和中红外区反射光谱和光声光谱的吸收特征及其差异。结果表明,中红外光谱比近红外光谱的信息更为丰富,且中红外光谱与样品中物质的特征吸收关系更加密切,从而更有利于土壤定性与定量分析。土壤的反射光谱和光声光谱表现出了明显不同的特征,在近红外区,反射光谱和光声光谱吸收明显不同,而在中红外区,反射光谱和光声光谱具有相对应的吸收,但相对吸收强度明显不同,且吸收峰的位置也发生改变,尤其在1 000 ~ 2 000 cm-1谱区,反射光谱相互干扰很强,而光声光谱的吸收特征更为明显。在黄土的分类鉴别上,反射光谱优于光声光谱。红外反射光谱和光声光谱在不同波段下具有不同的吸收灵敏度,在土壤定性与定量分析中各自都将具有其明显的优势。  相似文献   
129.
We investigated sunflower leaf palatability to Chlosyne lacinia saundersii Doubleday & Hewitson (Lepidoptera: Nymphalidae) in plants treated with silicon (Si) and subjected to mechanical injury. We also examined the effects of those treatments on plant development. The experimental study was carried out as a completely randomized design, consisting of the six treatments (10 replicates each): (1) control, (2) plants mechanically injured, (3) Si applied around the plant stem (Si drench), (4) Si drench + injured, (5) Si drench + foliar spray, and (6) Si drench + foliar spray + injured. Si drench + injured significantly reduced the percentage of caterpillar-injured leaves (CIL), leaf area consumed (LAC), and caterpillar weight (CW), leading to increased caterpillar mortality. The only intrinsic plant characteristic affected by the treatments was Si content (SiC), which was higher in plants treated with either Si drench + foliar spray or Si drench + foliar spray + injured. Negative correlations were observed between SiC and the variables CIL, LAC and CW, whereas positive correlations were observed between CIL and LAC, CIL and CW, and LAC and CW. The treatment strategy of Si combined with artificial mechanical injury affects leaf palatability and development of C. lacinia saundersii, conferring resistance to sunflower plants as a function of Si accumulation, although it did not increase crop vegetative variables.  相似文献   
130.
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