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51.
Ba A Lesnoff M Poccard-Chapuis R Moulin CH 《Tropical animal health and production》2011,43(6):1101-1109
The herds of 95 families were monitored for 1 year in eight villages in the cotton-growing region of southern Mali. In 2006–2007,
reproduction performances were average, with 0.54 calvings/year per cow, and mortality was low. Herd numerical productivity
is not very high, less than 0.13/year, because of the high proportion of males kept for animal draught. Depending on the herd
size, the behaviour of the families differs, in terms of off-take and in-take of animals. Families that only have one or two
draught animals seek to increase their animal draught capacity, with a negative net off-take (−0.13/year). Families with two
to three cows have a very low net off-take (0.02/year), with culling of adult animals compensated by purchase. They therefore
capitalised this year, with an annual herd growth of 8%. Families with a very large herd (20 to 50 cows) take off more of
their stock, with a net off-take of 0.08/year (very few animal purchases) and make a stock growth of 5%. And finally, families
with an average-sized herd (6 to 19 cows) take off the whole of the year’s production, with a net off-take of 0.11/year and
a nil stock growth rate. The use of a demographic model made it possible to measure the sensitivity of the productivity rate
to the different demographic parameters. 相似文献
52.
Toghyani M Toghyani M Shahryar HA Zamanizad M 《Tropical animal health and production》2011,43(6):1183-1189
The objective of this study was to evaluate the effects of two methods of early-age water restriction on performance, some
immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks. One-hundred-eighty-seven-day-old chicks
(Ross 308) were allocated to three treatments with four replicates based on a completely randomized design. Treatments included
the control group, where birds had free access to water, and water-restricted groups, where access to water was limited to
three 2-h periods (WRT1) or a 12-h period (WRT2) per day from days 7 to 17. Chicks in the control group were significantly
heavier (P < 0.05) at 17 and 46 days of age compared to the restricted birds. In the WRT2 group, feed intake decreased significantly
over the 17- to 28-day period while feed conversion ratio was poorer during water restriction (P < 0.05). Antibody titers against Newcastle and SRBC were higher (P < 0.05) for chicks with ad libitum access to water. Birds in the restricted groups exhibited a higher heterophil to lymphocyte
ratio compared to the control group (P < 0.05). The treatments had no significant impact on serum metabolites including protein, triglyceride, total cholesterol,
high-density lipoprotein and low-density lipoprotein cholesterols, calcium, and phosphorus concentrations. Walking ability,
tibial dyschondroplasia, foot pad, hock burn, and valgus/varus angulation were not significantly influenced by water restriction.
In conclusion, the current results indicate that early-age water restriction negatively influenced productive traits and immunological
responses of broiler chicks and failed to have any favorable impacts on leg health. 相似文献
53.
Ruiz-Fons F Fernández-de-Mera IG Acevedo P Höfle U Vicente J de la Fuente J Gortazár C 《Veterinary parasitology》2006,140(1-2):133-142
Commercial hunting of Spanish wild ungulates has made them an important economic resource. Wild ungulates may have an important role in the maintenance of ixodid tick populations, and also as reservoirs of pathogens. We studied the ixodid ticks that parasitize Iberian red deer and European wild boar from Spain. Ixodid ticks (n=6,336) were collected from 431 Iberian red deer and 142 wild boar in different regions of Spain. We found 10 different ixodid tick species parasitizing Iberian red deer, mainly Hyalomma marginatum marginatum (63.7%), Rhipicephalus (Boophilus) annulatus (7.9%) and R. bursa (7.5%). R. (Boophilus) annulatus was only collected in the province of Cádiz (southern Spain). We found 8 ixodid tick species on the wild boar, mainly Hy. m. marginatum (68.7%), R. bursa (14.6%) and Dermacentor marginatus (9.3%). We found one adult Hy. marginatum rufipes and one adult Hy. anatolicum excavatum parasitizing wild boar from south-central Spain. Mean prevalence of ixodid ticks was 41.3+/-0.08% (n=475) and 31+/-0.09% (n=284) and intensity of parasitization was 13.9+/-0.2 (n=283) and 13.6+/-0.3 (n=130) ticks/animal for Iberian red deer and wild boar, respectively. Only 5 of the 13 ixodid tick species found were shared by Iberian red deer and wild boar. This finding could indicate a host preference when Iberian red deer and wild boar share common habitats. In both Iberian red deer and wild boar from south-central Spain the monthly relative frequencies of Hy. m. marginatum and R. bursa presented an inverse pattern. The highest Hy. m. marginatum relative frequencies coincided with the lowest R. bursa relative frequencies along the year. R. bursa and I. ricinus were present in areas from northern to southern Spain while Hyalomma sp. and D. marginatus were exclusively collected in the two southern thirds of Spain. Haemaphysalis sp. and D. reticulatus were collected in northern Spain. Hy. m. marginatum and R. bursa were present during the whole year in red deer and wild boar from south-central Spain, showing more than one life cycle per year. These results are important for understanding the role of wild ungulates in the maintenance of tick infestations and to improve tick control programmes. 相似文献
54.
Zhongqi Cheng Leda Lee Sara Dayan Michael Grinshtein Richard Shaw 《Journal of Soils and Sediments》2011,11(4):628-638
Purpose
Gardening (especially food growing) in urban areas is becoming popular, but urban soils are often very contaminated for historical reasons. There is lack of sufficient information as to the bioavailability of soil heavy metals to plants and human in urban environments. This study examines the relative leachability of Cr, Ni, As, Cd, Zn, and Pb for soils with varying characteristics. The speciation and mobility of these metals can be qualitatively inferred from the leaching experiments. The goal is to use the data to shed some light on their bioavailability to plant and human, as well as the basis for soil remediation. 相似文献55.
Rui A. Gonçalves Tu Do Cam Nguyen Nhu Tri Gonçalo A. Santos Pedro Encarnação Le Thanh Hung 《Aquaculture International》2018,26(3):921-936
Triplicate groups of one hundred Tra catfish (8 g?±?0.2) were fed seven test diets containing increasing levels of AFB1 (0, 50, 100, 250, 500, and 1000 μg AFB1 kg?1). Additionally Mycofix® Secure was added at 1.5% to one diet containing 500 μg AFB1 kg?1. Results showed that Tra catfish are sensitive to AFB1. Reduction in weight gain (P?<?0.05) was observed for fish fed 50 μg AFB1 kg?1 and declined further with increasing levels of AFB1 in the diets. Fish fed diets contaminated with 500 and 1000 μg AFB1 kg?1 showed increased (P?>?0.05) hepatosomatic index (HIS), while an increase in adipose somatic index (ASI) was observed in fish fed 50 μg AFB1 kg?1 and above when compared to the control and Mycofix® diets. After 12 weeks, blood serum analysis revealed higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in fish fed the 50, 100, and 250 μg AFB1 kg?1 suggesting occurrence of liver damage. Disease resistance of fish exposed to Edwardsiella ictaluri was also compromised by the presence of AFB1 in the feed and was directly related to the contamination level. Seven days after Edwardsiella ictaluri exposure, survival rates were 50, 41.7, 31.7, and 8.3% for fish fed control, 50, 100, and 250 μg AFB1 kg?1, respectively. This trial shows that AFB1 at a level of 50 μg AFB1 kg?1 and above can affect fish performance and disease resistance. Application of an effective mycotoxin management in the feed seems to be useful to prevent the negative effects of AFB1. 相似文献
56.
Shiilegdamba E Carpenter TE Perez AM Thurmond MC 《Veterinary research communications》2008,32(3):201-207
Prior to 2000, foot-and-mouth disease (FMD) had not been observed in Mongolia since 1973; however, between April 2000 and
July 2002, Mongolia reported 44 FMD outbreaks that affected cattle, sheep, goats, and camels. The objectives of this study
were to describe the distributions of the 44 reported FMD outbreaks in Mongolia and to assess their spatial clustering and
directions of movement. Official reports were collected to obtain the number and species of animals both affected and at risk,
and the date and geographical coordinates of each outbreak. Significant global and local spatial clusters of reported FMD
outbreaks were identified. Disease spread during the second epidemic moved 76° northeast and the spread of the disease during
the third epidemic moved 110° northwest. FMD outbreaks were clustered intensely close to other FMD-positive counties. These
findings can be used in the future to help plan prevention and control measures in high risk areas. 相似文献
57.
Cooper RG 《Tropical animal health and production》2007,39(6):439-442
Data from post-mortem and field studies were obtained that discussed poisoning in ostriches following ingestion of toxic plants.
From the notes, all plants studied caused death in ostriches and there was systemic organ damage. Poisoning from Sarcostemma viminale (Melktou) resulted in beak patting, muscular tremors and head flopping, followed by collapse and violent kicking before death.
Ingestion of Combretum oatesii (Red wings) seeds from plants in free grazing pastures resulted in vomiting, restlessness, eyelid flicking, collapse and
kicking movements. Dichapetalum cymosum (Gifblaar) killed an ostrich after episodes of shaking legs, rapid respiration and bradycardia and hyperaemia of the lungs,
liver and kidneys. Poisoning from Senecio sceleratus (Ragwort) caused skin haemorrhages and bleeding in tracheal mucous membranes, the pericardium, diaphragm and interperitoneal
membrane. Consumption of drupes from Melia azedarach (Syringa berry) caused muscle tremors, kicking movements and respiratory distress. Lantana camara (Cherry pie) poisoning resulted in extremely inflamed eyes with copious yellow exudates extending down their beaks and onto
their necks. Bentonite was administered by gavage at a dose of 5 g/kg. Poisoning in these cases is usually associated with
the farmer allowing his/her birds to roam free-range in paddocks in which toxic plants are growing. Toxic plants should be
removed from grass cut for hay.
The author is willing to send photographs of all poisonous plants if requested by a reader. 相似文献
58.
Rosine Manishimwe Kizito Nishimwe Lonzy Ojok 《Tropical animal health and production》2017,49(6):1101-1106
The irrational use of antibiotics in humans and animals is highly related to the emergence and increase of antibiotic-resistant bacteria worldwide. A cross-sectional survey aimed at evaluating the current level of practices regarding antibiotic use in farm animals in Rwanda was carried out countrywide. Interviews were conducted on 229 farmers rearing different types of animals. The study has revealed that almost all respondent farmers could name at least one antibiotic used in farm animals and peni-streptomycin was named by most of them (95.6%). The use of antibiotics in farm animals was observed in the majority of respondents (97.4%). It was found that 44.4 and 26.5% of respondents reported that they used antibiotics for disease prevention and growth promotion, respectively. The use of non-prescribed antibiotics in animals was also reported by more than the half of respondent farmers (55.6%). The majority of farmers had a moderate level of practices regarding antibiotic use in farm animals (73.5%), very few had a high level (26%) and only one respondent had a low level. The high level of practices in regard to antibiotic use in animals was associated with the location of the farm, the type of reared animals, and the rearing system. The results of this study give an insight into antibiotics usage practices in farm animals in Rwanda. The generated information can guide sensitizations and promotions of the prudent use of antibiotics among farmers in order to limit the increase of antibiotic resistance in the country. 相似文献
59.
Lian-Ben Chang Chih-Jen Chou Jia-Shian Shiu Po-An Tu Shi-Xuan Gao Shao-Yu Peng Shinn-Chih Wu 《Tropical animal health and production》2017,49(6):1157-1162
Our aim was to investigate insemination techniques in order to improve pregnancy rates of artificial insemination (AI) using sex-sorted semen (sexed AI) in cattle in tropical and subtropical (T/ST) regions. In T/ST regions, the pregnancy rates by sexed AI are reportedly the lowest in the hottest months of the year, with less than 15% in cows and 35–40% in heifers (PMID 24048822). We compared sexed AI by depositing the semen into the uterine body (UB-AI, n = 12) versus the unilateral uterine horn (UUH-AI, n = 14) of pre-ovulation heifers. The ovary and follicle were assessed by rectal ultrasound before AI. After insemination, pregnancy was determined by ultrasound at approximately 40 days and approximately 70 days. In the present study, we demonstrated that high pregnancy rates (>70%) by sexed AI in the hottest season in a subtropical region such as Taiwan can be achieved when heifers with pre-ovulation follicles are used. The overall pregnancy rates were 54% higher in the UUH-AI (71%) group than in the UB-AI (42%) group (P = 0.06), examined on approximately 40 days post-sexed AI. Surprisingly, however, the pregnancy outcome appeared to be higher in the hot season (62%) than in the cool season (46%) although this difference was not statistically significant. Based on the present study, we recommend that cattle breeders perform UUH-AI using sex-sorted semen for heifers with pre-ovulation follicles in order to achieve satisfactory pregnancy outcome in the hot seasons in T/ST regions. 相似文献