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31.
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
32.
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
33.
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
34.
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
35.
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
36.
Mersha Chanie Tamiru Negash Asegedech Sirak 《Tropical animal health and production》2010,42(6):1103-1109
Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological
studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites,
lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were
collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and
600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and
ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained
skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the
basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory
cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions
caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as
skins are the major export commodity of the country. 相似文献
37.
Ahmad Oryan Fatemeh Namazi Mohammad-Mehdi Namavari Hassan Sharifiyazdi Marjan Moraveji 《Veterinary research communications》2010,34(5):423-434
This study was performed to evaluate the infectivity of bradyzoites of two Besnoitia caprae isolates, BC-1 and BC-2, to inbred BALB/c mice. Each group of inbred BALB/c mice was inoculated intraperitoneally with 1 × 103, 1 × 104, 1 × 105, 5 × 105 and 1 × 106 of one of the two isolates of B. caprae bradyzoites. The mice were monitored daily for a period of 40 days for survival. After death of each mice, several passages
from its peritoneal washing and tissues were analyzed using ribosomal DNA-specific PCR assay. Marked differences in pathogenicity
between the isolates were seen. All the inbred BALB/c mice infected with BC-2 survived but all the mice that were administered
with 1 × 05, 5 × 105 and 1 × 106 BC-1 bradyzoites were died within 4–9 days post-infection (DPI). Histopathological examination of the tissues of the dead
mice revealed hyperemia and necrosis with presence of mononuclear and polymorphonuclear cell infiltration in myocardium, spleen
and intestines together with interstitial pneumonia and peritonitis. All inbred BALB/c mice in the 1 × 103 and 1 × 104 groups of BC-1 inoculated mice survived and they were euthanized after 40 DPI. Chronic inflammation with infiltration of
mononuclear cells was evident in myocardium, spleen, alveolar septa of the lungs of most of the examined tissues with hemorrhagic
enteritis in the mice infected with 1x106 bradyzoites. The mice infected with different doses of BC-2 were euthanized after 40 DPI and no lesion was seen in histopathological
sections of their organs. All peritoneal washings and examined tissues were PCR positive in BC-1 group. This experiment is
the first report to show inbred BALB/c mice as a relevant model for B. caprae and demonstrates that this strain of inbred BALB/c mice is a suitable animal model for biological studies and examination
of pathogenesis for this species of Besnoitia. The present findings also provide evidence for significant differences between the two isolates of B. caprae. 相似文献
38.
The effect of a single intramammary infusion of a biological response modifier in cows at drying off
Bibiana Elisabet Dallard H. H. Ortega I. A. Iguzquiza N. R. Salvetti O. A. Quaino L. F. Calvinho 《Veterinary research communications》2010,34(6):519-532
Biological response modifiers (BRM) are compounds that interact with the immune system to regulate specific aspects of host
response. The objective of this study was to describe clinical and morphological changes during involution of bovine mammary
gland following a single-dose infusion of a BRM containing lipopolysaccharide and cellular fractions of Escherichia coli incorporated into liposomes. A massive leukocyte response and increased subepithelial stroma infiltration of mononuclear
cells, eosinophils and mast cells was observed in BRM-treated quarters compared with untreated controls; however, morphologic
parameters assessed at 11 days post infusion were indicative of only slightly accelerated involution compared with untreated
controls. In addition, BRM infusion at the end of lactation did not interfere with mammary epithelial cell proliferation and
caused only mild systemic effects. 相似文献
39.
Denis M Lacy-Hulbert SJ Buddle BM Williamson JH Wedlock DN 《Veterinary research communications》2011,35(3):145-156
The presence, phenotype and function of Streptococcus uberis-specific T cells in the mammary gland secretion (MGS) and blood of cows exposed to S. uberis were assessed. MGS T cells in the udder were purified and incubated with autologous blood monocytes as antigen-presenting
cells (APC). Most cows, irrespective of prior S. uberis infection status and lactation status, were shown to have S. uberis-specific T cells both in MGS and in the blood. When cells from a subgroup of cows were studied, it was found that the S. uberis-specific T cells produced high levels of interferon-gamma (IFN-γ), but low levels of interleukin-10 (IL-10). A high percentage
of responding T cells were of the CD8
+
memory (CD45RO) subset. T cells from the MGS specific for S. uberis were propagated from animals during the drying off period and expanded in vitro using interleukin-2 (IL-2) and S. uberis antigens. This led to the accumulation of T cells of the CD8
+
subset bearing memory cell markers (CD45A
−
, CD45RO
+
), which released high levels of IFN-γ. Four of the five T cell lines derived from the MGS of three animals had substantial
direct killing activity towards S. uberis in vitro. It is concluded that there is an emergence of S. uberis-specific bactericidal T cells in the MGS of cows after infection or environmental exposure to S. uberis. Vaccines aimed at activating and expanding this T cell population in the mammary glands of cattle may offer an avenue for
the prevention of mastitis caused by S. uberis. 相似文献
40.
Ornithobacterium rhinotracheale is a gram negative bacterial pathogen causing respiratory tract infections in poultry. Tracheal, lung and serum samples were
obtained from 21 broiler flocks of 8 farms from a slaughterhouse located in south-eastern of Iran. Among 630 tracheal and
lung samples from samples resulting from 315 chickens, 11 (3.5%) ORT isolates were identified using biochemical tests. The
isolates originated from 9 (42.9%) flocks out of 4 farms. All of the isolates were recovered from tracheal swabs and showed
an API 20NE identification biocode 0-2-2-0-0-0-4. Of the 420 serum samples examined by ELISA, 134 (31.9%) sera from 17 (81.0%)
flocks were positive for ORT antibodies. These results indicate that ORT is present in most broiler flocks with respiratory
disorders in southeast Iran. 相似文献