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91.
Livestock production is an integral part of the rain-fed and irrigated agriculture system in Pakistan. Animal production is closely interlinked with the cropping systems and play a crucial role in the rural economy. Participatory rural appraisals and economic opportunity surveys were conducted in two ecological zones (irrigated and rain-fed) and two dairy production systems (peri-urban and mixed livestock). Major constraints in animal health, nutrition and reproduction were identified and interventions were suggested to overcome these difficulties. The economic opportunity survey revealed that maximum opportunity to enhance farmers’ income is to increase milk production per day per animal, which can be accomplished through coordinated improvements in nutrition, reproduction and genetics.  相似文献   
92.
Infective corneal diseases are common among the domesticated elephants in Sri Lanka, causing morbidity including blindness leading to loss of revenue to their owners. From 140 elephants of different ages and both sexes, 36 animals (25.7%) had evidence of keratitis, corneal ulcers, corneal opacities, and some had foreign bodies in their eyes. Nine elephants (6.4%) had lesions in both eyes (6.41%). Cultures for both bacteria and fungi were obtained from 26 corneal ulcers, including the nine elephants with bilateral lesions. The other 10 animals could not be restrained for sample collection. Swabs from the normal corneas of an additional 20 elephants without signs of any ophthalmic diseases were also collected. Twenty-three of the 35 (65.71%) samples from affected corneas yielded bacterial pathogens, and 14 (40%) also had fungal isolates. None of them yielded a fungal isolate alone. The predominant bacteria isolated were Staphylococcus aureus , beta hemolytic streptococci and coliforms. Fusarium , Cladosporium , Curvularia and Aspergillus species were the primary fungal isolates. No bacteria or filamentous fungi were isolated from the eyes with the normal corneas. Microbial identification including fungal isolations is suggested in the management of infective corneal diseases in elephants.  相似文献   
93.
The effect of exogenous amylase on the in vitro rumen digestion kinetics of whole-crop maize silage made from dent (RB9004) or flint grain type (RB9308) was evaluated at different phenological stages: soft dough (SOD), early dent (EAD), ½ milkline (½M) and ¾ milkline (¾M). Forage was harvested from 70 to 110 days after sowing. Two rumen-cannulated cows receiving or not exogenous amylase (0.7 g/kg dry matter—DM, provided to achieve 396 kilo Novo units of amylase activity/kg of TMR DM) were used as donor of ruminal fluid. The in vitro gas production kinetics was evaluated according to a dual-pool logistic model. The chemical composition and gas production kinetics were affected by the hybrid and phenological stages. The flint hybrid had lower range for chemical analysis among physiological stages. Harvesting at ½M and ¾M improved DM content, bromatological composition and silage quality parameters compared to dent or flint types. Amylase (i) increased methane (CH4) production and in vitro dry matter digestibility (IVDMD) in ½M stage, (ii) improved digestion kinetics by reducing lag time and increasing total gas production and fermentation rates of non-fibrous carbohydrates (NFC) and fibrous carbohydrates (FC), and (iii) increased extent and fermentation rate of NFC and increased fermentation rate of FC fraction in whole-crop maize silages produced from dent or flint types in all phenological stages. Harvesting between ½M and ¾M is the best phenological stage to improve chemical composition and silage quality parameters. Exogenous amylase showed improvements on fibre digestion of silages at ½M and ¾M phenological stages in both grain types of corn.  相似文献   
94.
Tropical Animal Health and Production - The possible influence of the “male effect” upon reproductive outcomes of adult anestrous goats under marginal rangeland conditions and...  相似文献   
95.

The aim of the present study was to describe the strategies of the control of an outbreak of leptospiral infection in dairy cattle in Maranhão State, Northeastern Brazil. In the period from January to July 2015, 18 (17%) out of 106 cows presented abortion, six (5.7%) stillbirth, and 12 (11.3%) repeated estrus, totaling 24 animals with reproductive problems. The diagnosis of leptospirosis was based on serology (microscopic agglutination test—MAT), bacteriological culture, and polymerase chain reaction (PCR). Antibiotic therapy, vaccination protocols, and changes in management practices were suggested as control measures. Of all animals on the farm (n?=?280), 136 (48.6%) were seropositive for at least one serovar of Leptospira sp. No pure leptospiral culture was obtained. Eight of the animals with reproductive problems yielded positive PCR results (vaginal fluid of seven animals and urine and vaginal fluid of one animal). Genetic sequencing of a vaginal fluid/urine PCR-positive sample revealed Leptospira borgpetersenii. One year after the adoption of control measures, no reproductive problems were observed. Thus, leptospirosis probably caused the reproductive failures in the herd, and the control and prevention measures implemented were efficient in controlling the disease.

  相似文献   
96.
Intravenous paclitaxel has been underused in dogs due to severe and acute hypersensitivity reactions. Subcutaneous (SC) administration of paclitaxel and its safety are unknown. In this preliminary study, SC administration of paclitaxel was evaluated for hypersensitivity reactions and toxicity in 21 dogs with advanced cancer. Dogs received 1 to 5 paclitaxel doses, ranging from 85 to 170 mg/m2, SC every 14 or 21 days. A total of 40 paclitaxel doses were administered and none of the 21 dogs developed systemic or acute local hypersensitivity reactions. Severe skin lesions at the injection site developed in 2 dogs after the 4th injection at the same location. Grade 4 neutropenia was observed in 50% of the dogs 5 days after the first treatment at 115 mg/m2 (n = 14). Two animals developed Grade 5 diarrhea and died likely due to hemodynamic failure or sepsis. Paclitaxel can be administered SC in dogs with no hypersensitivity reaction.  相似文献   
97.
Granulosa cell tumour (GCT) is a majorly observed ovarian tumour in female dogs. It is essential to diagnose GCT in its initial phase before any symptoms occur, as histological and physiological differences may be observed based on the evolution of this neoplasia. This study aimed to analyse the anatomic histopathology of GCT in its initial stage, with findings of ovaries not yet with the suspicion of neoplasms in the Canis familiaris. A sample including 55 ovaries presented GCT in 40 female dogs. The histopathological analysis was performed considering the intensity of pleomorphism, vascularization and inflammatory infiltrate. Furthermore, we evaluated the mitoses count in 10 fields using 40× magnification. Out of the 40 animals evaluated, 62.5% (25/40) presented the tumour in only one ovary. The Call‐Exner corpuscle was present in 65% (26/40) of the cases. The follicular histological pattern was present in 52.5% (21/40) of the animals. The presence of the Call‐Exner bodies and the degree of tumour cell pleomorphism (p = 0.033) were associated. Moreover, the degree of vascularization and the intensity of the inflammatory infiltrate were also related (p = 0.001). In addition, there was a positive relationship between the increase in pleomorphism and the mean age of the animals (p = 0.044). This study confirmed that the appearance of this tumour may precede any clinical symptomatology. In this study, the most frequent histopathological pattern was the follicular. The characteristics of the granulosa cell tumour diagnosed early were poorly pleomorphic cells, low mitotic index and presence of Call‐Exner body.  相似文献   
98.
The objective of this study was to analyse the effects of different levels of rumen-degradable protein (RDP) on intake, digestibility and microbial protein synthesis by supplementing mustard oil cake (MOC) on rice straw-based diet of cattle (Bos indicus) in Bangladesh. A 4 × 4 Latin square design was applied. Four diets having constant energy (7.0 MJ/kg of dry matter (DM)) with varying levels of RDP (M 0 = 4.1 g/MJ (control), M 1 = 6.3 g/MJ, M 2 = 8.3 g/MJ and M 3 = 12.4 g/MJ of metabolizable energy (ME)) were received by each animal for a period of 28 days. A metabolism trial was conducted for 7 days. Results indicate that with increasing levels of RDP, crude protein (CP) and RDP intake increased significantly (P < 0.01). The significant (P < 0.01) increase in digestibility values are obtained for DM, organic matter, CP and digestible organic matter in the rumen. The digestibility of neutral detergent fibre and acid detergent fibre was also increased significantly (P < 0.05). The total nitrogen (N), ammonia-N and total volatile fatty acids increase significantly (P < 0.01) while the rumen pH increased from M 0 to M 2 and decreased thereafter. The efficiency microbial N intake increased significantly (P < 0.01) but showed a curvilinear response with higher RDP level (12.40 g/RDP/MJ ME). This study concludes that supplementation of RDP from MOC enhances the intake, digestibility and microbial protein synthesis which ultimately increases utilization of low-quality feed resources that can be used for developing cost-effective feeding systems on a straw-based diet in tropical regions.  相似文献   
99.
Indigenous chicken (IC) and their production systems were characterized to understand how the whole system operates for purposes of identifying threats and opportunities for holistic improvement. A survey involving 594 households was conducted in six counties with the highest population of IC in Kenya using structured questionnaires. Data on IC farmers’ management practices were collected and analysed and inbreeding levels calculated based on the effective population size. Indigenous chicken were ranked highest as a source of livestock income by households in medium- to high-potential agricultural areas, but trailed goats in arid and semi-arid areas. The production system practised was mainly low-input and small-scale free range, with mean flock size of 22.40 chickens per household. The mean effective population size was 16.02, translating to high levels of inbreeding (3.12%). Provision for food and cash income were the main reasons for raising IC, whilst high mortality due to diseases, poor nutrition, housing and marketing channels were the major constraints faced by farmers. Management strategies targeting improved healthcare, nutrition and housing require urgent mitigation measures, whilst rural access road network needs to be developed for ease of market accessibility. Sustainable genetic improvement programmes that account for farmers’ multiple objectives, market requirements and the production circumstances should be developed for a full realization of IC productivity.  相似文献   
100.
A study was undertaken from October 2006 to March 2007 to determine the prevalence and antimicrobial resistance patterns of Salmonella serovars. Liver, mesenteric lymph nodes, intestinal content, and carcass swab samples (each n?=?186) were collected from 186 apparently healthy slaughtered cattle at Bahir Dar abattoir. Bacteriological analysis was done according to the International Organization for Standardization (ISO 6579 2002). Isolates were serotyped at Agence Française de Securite Sanitaire des Aliments, Cedex, France. Twenty-eight isolates consisting of Salmonella Typhimurium, Salmonella Newport, Salmonella Haifa, Salmonella Heidelberg, Salmonella Infantis, and Salmonella Mishmarhaemek were identified. Salmonella Typhimurium and Salmonella Newport were most frequently isolated while Salmonella Heidelberg and Salmonella Mishmarhaemek were isolated least. Eleven of the 28 (39.3%) were resistant to one or more of the antimicrobials tested. Resistance was shown to ampicillin, chloramphenicol, gentamycin, norfloxacin, polymyxin-B, streptomycin, tetracycline, and trimethoprim. Four of 11 (36.4%) were multiple antimicrobial resistant. All the isolates tested were susceptible to the antimicrobial effects of gentamycin, norfloxacin, and trimethoprim. Eleven, four, and two isolates of the 28 were resistant to streptomycin, tetracycline, and ampicillin, respectively. All isolates of Salmonella Infantis, Salmonella Typhimurium (except one), and Salmonella Mishmarhaemek were susceptible to the tested antimicrobials. One Typhimurium isolate was resistant to chloramphenicol, streptomycin, and tetracycline. Salmonella Haifa was multiply antimicrobial resistant to ampicillin, tetracycline, and streptomycin. All isolates of Salmonella Heidelberg were resistant to streptomycin. Results of this study indicated high level of carcass contamination with antimicrobial-resistant Salmonella serovars which could pose public health risk; suggests need for hygienic slaughtering operations and proper cooking of meat before consumption. Further detailed studies involving different abattoirs, animal products, food items, and animals on different settings were recommended in the study area.  相似文献   
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