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31.
Maddur MS Mohan MS Gajendragad MR Kishore S Gopalakrishna S Singh N 《Veterinary research communications》2009,33(2):103-109
Humoral and mucosal (secretory antibody)immune response to FMDV type Asia 1 in cattle was analyzed after vaccination and infection
using virus neutralizing test (VNT). Vaccination (1/16th the usual dose) failed to protect cattle from generalized clinical
disease following experimental FMDV Asia 1 infection. Our results showed that infection induced higher and prolonged serum
antibody titres indicating antigen mass is important for optimal immune response. Experimental FMDV infection induced significant
secretory antibody (mucosal) response in cattle. Though, there was no difference in the serum antibody response between the
cattle that developed generalized infection (unprotected) and those with only localized infection (protected), secretory antibody
response differed, wherein the unprotected cattle had higher secretory response than protected cattle. Thus, FMDV Asia 1 infection
stimulates a similar serum antibody response and a unique secretory antibody response among the infected cattle.
An erratum to this article can be found at 相似文献
32.
Gerardo Ordaz-Ochoa Aureliano Juárez-Caratachea Rosa Elena Pérez-Sánchez Rafael María Román-Bravo Ruy Ortiz-Rodríguez 《Tropical animal health and production》2017,49(5):1025-1033
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI. 相似文献
33.
Moazenijula G Jabbari AR Geravand MM Banihashemi R Hajizadeh A 《Tropical animal health and production》2011,43(8):1471-1474
The anaphylactic reactions in cattle following leptospira vaccination mostly booster dose in different parts of Iran have
been reported. The serum proteins as allergic substances are components of liquid phase of the vaccine. Therefore, the vaccine
was modified by washing the whole cultures by centrifugations. The modified vaccine was safe in laboratory animals and cattle
as well as under field conditions. Microagglutination test revealed a similar pattern of antibody response to the three Leptospira interrogans serovars (Canicola, Grippotyphosa, and Sejro hardjo) in all vaccinated cattle groups while was higher than the response of
control animals. The results of the present investigation revealed that we can minimize postvaccination shock in vaccinated
cattle populations with removing the shock proteins. 相似文献
34.
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
35.
36.
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
37.
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
38.
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
39.
Recently, significant progress has been achieved in improving the yield of good quality embryos in vitro. However, efforts are still required to recognize the factors and understand the mechanisms of oocyte maturation, which are essential for subsequent embryo development. The aims of the present study were to determine the frequency of apoptosis in oocytes recovered from slaughterhouse ovaries and to investigate whether insulin-like growth factor (IGF)-I action during oocyte maturation in vitro may withhold apoptosis and improve oocyte quality. Only oocytes of proper morphology with homogenous ooplasm and compact cumulus cells were selected for this study. All oocytes recovered from the slaughterhouse ovaries were divided into two groups. One group of oocytes, chosen for apoptosis detection, was examined immediately after recovery. The other group of oocytes was maturated in vitro. Oocytes were maturated with IGF-I supplementation (100 ng/ml). Oocytes without supplementation were used as a control. Apoptosis in oocytes was determined by positive results of TUNEL assay and active caspase labeling. The percentage of apoptotic oocytes detected by TUNEL fell to zero when the maturation medium was supplemented with IGF-I in comparison to the control matured oocytes (0 vs. 9.87%; P<0.05). However, active caspase labeling was only slightly decreased in the IGF-I matured oocytes compared with the control matured oocytes (1.13 vs. 2.08%; P<0.05). The results indicate that IGF-I may serve as an anti-apoptotic factor during oocyte maturation. We suggest that IGF-I may inhibit apoptosis in oocytes at the stage of caspase activation and may prevent further advancement of oocyte apoptosis. 相似文献
40.
Marcos R Santos M Marrinhas C Rocha E 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(1):106-109
An 11-month-old prepubertal crossbreed female dog was presented with multiple nodular lesions disseminated over the cervical, back, flank, and abdominal regions. The lesions were ulcerated and cauliflowerlike, or nodular and subcutaneous, measuring up to 13 cm in diameter. Cytologic preparations of one of the lesions revealed a uniform population of round to oval cells, with lightly basophilic cytoplasm that contained multiple distinct vacuoles. Frequent mitotic figures and occasional lymphocytes were also observed. The cytologic diagnosis was cutaneous transmissible venereal tumor (TVT) in a progressing growth phase. This was confirmed by histologic and immunohistochemical findings. Vaginal TVT was diagnosed later in the dog's mother. TVT is a contagious neoplasm of sexually mature dogs that usually is transmitted by coitus and affects the genital mucosa. To our knowledge, this is the first report of naturally occurring multicentric TVT in a prepubertal female dog and also is unique in its exclusively cutaneous (no mucosal) involvement. We speculate that transmission of neoplastic cells occurred during cohabitation and social/mothering behavior between the dogs. Despite the atypical clinical presentation, response to chemotherapy with vincristine was excellent, leading to complete regression of the neoplasm without relapse after 6 months. 相似文献