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Factors affecting hematological profiles in three Ethiopian indigenous goat breeds
2004
Tibbo, Markos | Jibril, Y. | Woldemeskel, M. | Dawo, F. | Aragaw, K. | Rege, J.E.O.
Hematological parameters were studied in 163 apparently healthy goats comprised of 3 indigenous breeds at Adami-Tulu Agricultural Research Centre (ATARC) and Sheno, Agricultural Research Centre (SARC), Ethiopia. Data were analyzed for the effect of breed, sex, age, and season. Hemoglobin (Hb) was significantly higher (P < 0.0001) for Arsi-Bale (AB) than Longeared Somali (LES) and Central Highland (CH) goats. Packed cell volume (PCV) was significantly lower (P < 0.0001) for LES than the other two breeds. White blood cells (WBC) (P < 0.05), neutrophils (P < 0.0001) and basophils (P < 0.0001) were higher in CH than in the other two breeds. Conversely, lymphocytes were lowest (P < 0.0001) in CH goats compared to other breeds. Female goats had significantly (at least P < 0.05) higher red blood cells (RBC), PCV, WBC, lymphocytes and eosinophils than male goats. In contrast, males had higher (P < 0.05) mean corpuscular hemoglobin (MCH) and neutrophils than females. There was no significant age difference for the erythrocytic series but the age difference was highly significant (P < 0.0001) for the leukocytic series. WBC and lymphocytes decreased as age increased while the reverse was true for neutrophils and eosinophils. Seasonal variation was also considerable for both erythrocytic and leukocytic series. RBC, Hb, lymphocytes, and neutrophils of the indigenous goat breeds were remarkably different compared to most other exotic goat breeds.
Afficher plus [+] Moins [-]Age and seasonal pattern of contagious agalactia in small ruminants in Ukraine
2021
Bohach, Dmytro Mykolaivych | Stegniy, Borys Tymofiyovych | Bohach, Mykola Volodymyrovych | Pavlov, Serhii Leonidovych | Bolotin, Vitaliy Igorovych
The aim of the study was to determine how the spread of contagious agalactia in sheep and goats in the Odesa region depended on the age of the animals and the season. From January 2016 to December 2018, 1,964 ewes and 1,484 nanny goats of different age groups were studied by ELISA for antibodies to Mycoplasma agalactiae. The highest incidence of contagious agalactia was registered in one-year-old animals and was 59.7‒83.0%, two-year-old ruminants showed 17.0‒40.3% prevalence, in livestock at the age of 3–4 years no serological evidence of the disease was registered and in ewes and nanny goats older than 5–6 years 1.5–3.6% were infected. The most susceptible were young animals at the age of one-month (11.6‒14.5%). The first peak of the disease was recorded in March‒April (21.0‒26.1%), in the lambing period, which coincided with the beginning of lactation and the suckling period, and the second peak occurred in June–July (28.9‒34.2%), the period of maximum lactation and of manual milking of sheep and goats. The results of serological investigations indicate the circulation of M. agalactiae in small ruminants in the south of Ukraine. To avoid greater dissemination of the pathogen, appropriate measures should be applied and strategies for its control need to be drawn up.
Afficher plus [+] Moins [-]MDA and GSH-Px activity in transition dairy cows under seasonal variations and their relationship with reproductive performance
2017
Colakoglu, Hatice Esra | Yazlik, Murat Onur | Kaya, Ufuk | Colakoglu, Ekrem Cagatay | Kurt, Serdal | Oz, Burcu | Bayramoglu, Rustem | Vural, Mehmet Rifat | Kuplulu, Sukru
Introduction: The purpose of the current study was to evaluate the blood glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels under seasonal variations in dairy cows during transition period, and to assess the relationship between chosen reproductive parameters, GSH-Px, and MDA. Material and Methods: Holstein cows calving in January were assigned into winter group (n = 42), while cows calving in August were assigned into summer group (n = 42). Blood samples were collected from the jugular vein 21, 14, and 7 days before calving, at calving (0 day), and 7, 14, and 21 days after calving. Reproductive parameters obtained from farm records were evaluated. Results: In both groups of cows, GSH-Px activity decreased from 21 days before calving to day 0, and it gradually continued to increase until 21 days after calving. GSH-Px activity was higher in winter group compared to summer group during the transition period (P < 0.05). MDA levels in both groups increased over time starting from 21 days before calving to 0 day, but it gradually decreased thereafter. MDA levels were higher in summer group compared to winter group during the transition periods (P < 0.05). Summer group of cows showed higher intervals of calving-to-oestrus, calving-to-conception, and higher insemination index (P < 0.01). Negative correlation was recorded between GSH-Px and MDA during all examination days (P < 0.01). MDA levels correlated with calving to conception interval on day 21 before calving and day 0 (P < 0.01) and insemination index on day 0 and 21 days after calving (P < 0.01). GSH-Px activity was negatively correlated with calving to conception interval on day 21 before calving, day 0, and 21 days (P < 0.01) after calving. Negative correlation on day 21 before calving and day 0 was also determined between GSH-Px and insemination index (P < 0.01). Conclusion: This study showed that blood oxidant and antioxidant levels have affected the fertility parameters in cows under seasonal variations.
Afficher plus [+] Moins [-]Assessment of the long-term effect of vaccination on transmission of infectious bovine rhinotracheitis virus in cattle herds hyperimmunized with glycoprotein E–deleted marker vaccine
2012
Ampe, Bart | Duchateau, Luc | Speybroeck, Niko | Berkvens, Dirk | Dupont, Alain | Kerkhofs, Pierre | Thiry, Etienne | Dispas, Marc
Objective: To assess long-term effects and risk factors for the efficacy of hyperimmunization protocols against infectious bovine rhinotracheitis (IBR) during a longitudinal field study of dairy and dairy-beef mixed farms. Animals: Approximately 7,700 cows from 72 farms. Procedures: Farms were assigned to 3 treatment groups (hyperimmunization groups [HIGs] 1 and 2, which were hyperimmunized with glycoprotein E [gE]–deleted marker vaccines, and a nonintervention group [NIG]). Cattle in HIG 1 were initially vaccinated with an attenuated vaccine, whereas cattle in HIG 2 were initially vaccinated with an inactivated-virus vaccine. Cattle in both HIGs received booster inoculations with inactivated-virus vaccines at 6-month intervals. The risk for gE seroconversion was compared among experimental groups via a shared frailty model with a piecewise constant baseline risk to correct for seasonal and secular effects. Results: Risk for gE seroconversion significantly decreased over time for the HIGs, compared with the NIG. Seasonal changes in the risk of gE seroconversion were detected, with a higher risk during winter periods, compared with grazing periods. No significant difference was detected between HIGs 1 and 2. The only significant risk factor was the number of buildings for cattle on a farm; the higher the number of buildings, the lower the risk for gE seroconversion. Prevalence of IBR decreased over time in both HIGs but remained constant or increased in the NIG. Conclusions and Clinical Relevance: Hyperimmunization via repeated administration of attenuated and inactivated-virus gE-deleted marker vaccines as well as inactivated-virus vaccines may provide a method for control of IBR.
Afficher plus [+] Moins [-]Persistence of a single electropherotype and serotype (G6P5) of bovine rotavirus in calves on a closed dairy farm from 1990 to 1993
1995
Ishizaki, H. | Ohta, C. | Shirahata, T. | Goto, H. | Taniguchi, K. | Urasawa, T. | Urasawa, S.
A virologic survey was conducted on calves with diarrhea associated with bovine rotavirus (BRV) on a closed dairy farm. The BRV was detected from 32 of 219 (14.6%) fecal specimens repeatedly collected from 56 calves born during the years 1992-1993, regardless of whether they had diarrhea. Most of the 32 strains were isolated from fecal specimens obtained from 2-to 6-week-old calves. After electrophoresis of doublestranded viral RNA from the 32 strains, genomic RNA migration patterns were similar to those of the predominant BRV strains isolated at the same farm during the years 1990-1991. All representative strains were identified as G serotype 6 (G6) and P type 5 (P5) by results of the virus-neutralization test and polymerase chain reaction procedure. Thus, BRV had no change in genomic RNA electropherotypes and serologic antigenicities in a closed dairy herd over a period of several years.
Afficher plus [+] Moins [-]Enzymatic analysis of liver samples from rainbow trout for diagnosis of blue-green algae-induced toxicosis
1995
Microcystin and related toxic peptides produced by cyanobacteria (blue-green algae) are potent and selective inhibitors of protein phosphatases 1 and 2A. We adapted existing enzymatic techniques to analyze the liver of rainbow trout after oral administration of hepatotoxic cyanobacteria. Liver tissue was removed 3 and 12 hours after treatment, and phosphatase activity was determined in liver extracts, using a specific phosphoprotein substrate. In all samples from fish exposed to toxic cyanobacteria, phosphatase activity was suppressed, whereas the control enzyme, lactate dehydrogenase, present in the same liver extract, was not affected by cyanobacteria. Thus, experimental poisoning by hepatotoxic cyanobacteria resulted in an abnormally low ratio of phosphatase to lactate dehydrogenase activity in the liver extracts. These results indicate that specific inhibition of phosphatases 1 and 2A may provide a useful diagnostic tool to determine the early effects of cyanobacteria toxic peptides directly in liver samples from poisoned animals. Although this test was developed with rainbow trout, it should be possible to extend the analysis of liver phosphatase activity to other species, including sheep and cattle, which are frequently affected by hepatotoxic cyanobacteria.
Afficher plus [+] Moins [-]Retrospective evaluation of factors associated with the risk of seropositivity to Ehrlichia risticii in horses in New York state
1992
Atwill, E.R. | Mohammed, H.O. | Dubovi, E. | López Izquierdo, J.
A retrospective study was designed to determine the distribution of equine monocytic ehrlichiosis among the equine population in New York state, and to identify factors associated with risk of disease. Serum samples submitted to the diagnostic laboratory of the university during the period from January 1985 through December 1986 were examined for antibodies to Ehrlichia risticii, using the indirect fluorescent antibody technique. Factors evaluated included geographic origin and date of submission of the sample, and age, breed, and sex of the horse. Logistic regression analysis was used to identify which factors were significantly associated with the risk of seropositivity to E risticii, while simultaneously controlling for other factors. Of the 2,579 tested samples, 1,950 (76%) had positive results. Factors significantly associated with risk of seropositivity to E risticii were: breed of the horse (Thoroughbreds were 3 times more likely to have been exposed to E risticii, compared with non-Standardbred, non-thoroughbred breeds); sex (female horses were 2.7 times more likely to have been exposed, compared with male horses); age of the horse (the risk of being exposed to E risticii increased with age, peaked at around 12 years, and decreased thereafter); and month of submission (horses tested during November and December had the highest odds of being seropositive [odds ratio = 2.1], and horses tested during March through April were least likely to be seropositive [odds ratio = 0.5], compared with horses tested during January and February).
Afficher plus [+] Moins [-]Fungal flora of the healthy camelid conjunctival sac
1992
Gionfriddo, J.R. | Gabal, M.A. | Betts, D.M.
Swab specimens for fungal isolation were collected from the healthy conjunctival sacs of 3 species of captive camelids (Lama glama, L guanicoe, L pacos) and llama-guanaco hybrids. Fungi were collected from over half the animals in winter (53%) and summer (56%). Fungal species of 10 genera were isolated. In both seasons, Aspergillus was the most commonly isolated genus; at least 9 species of Aspergillus were found. The fungal organisms isolated were similar to those found in healthy eyes of other domestic animals and may represent a random seeding from the environment where they are ubiquitous.
Afficher plus [+] Moins [-]Prevalence of Cryptosporidium infection in dairy calves in western Washington
1989
Ongerth, J.E. | Stibbs, H.H.
The prevalence and intensity of Cryptosporidium infection were examined in 445 Holstein calves at 10 dairy farms in western Washington, near Seattle. Fifty-one percent (176) of calves in the 7- to 21-day-old age group (n = 342) were positive for oocysts in the feces by carbolfuchsin staining. Prevalence and intensity of infection were highest in calves 8 to 14 days old; prevalence was 60% in this group, and 48% of the Cryptosporidium-positive calves had oocyst shedding at a 4+ level. A seasonal pattern in prevalence was not evident.
Afficher plus [+] Moins [-]A temporal study of Salmonella serovars from environmental samples from poultry breeder flocks in Ontario between 1998 and 2008
2013
Sivaramalingam, Theva | McEwen, Scott A. | Pearl, David L. | Ojkic, Davor | Guerin, Michele T.
A temporal study was carried out to determine Salmonella prevalence, trends, major serovars, and their clusters from environmental samples, in poultry breeder flocks in Ontario between January 1998 and December 2008. Surveillance data were obtained from the Ontario Hatchery and Supply Flock Policy. Logistic regression with a random effect for flock was used to identify factors [poultry type, year (trend) and season] associated with the prevalence of Salmonella. A cluster detection test was used to identify clusters of common serovars. The period prevalence of Salmonella was 47.4% in broiler-breeder, 25.7% in layer-breeder, and 19.6% in turkey-breeder flocks. The overall trend in the prevalence of Salmonella was decreasing for all breeder types, due primarily to decreasing trends of Salmonella Heidelberg. The seasonal effects varied by year with the highest probability of Salmonella occurring in different seasons. The 4 most common serovars identified were Salmonella Heidelberg, Kentucky, Hadar, and Typhimurium in broiler-breeders; Salmonella Heidelberg, Brandenburg, Thompson, and Typhimurium in layer-breeders; and Salmonella Heidelberg, Saintpaul, Brandenburg, and Muenster in turkey-breeders. Salmonella Enteritidis was infrequently isolated in all poultry breeder types. Temporal clusters of different serovars were identified in all poultry breeder types. Clusters of Salmonella Heidelberg, Typhimurium, and Hadar from environmental samples from breeder flocks were detected during a similar period to clusters from hatchery fluff samples from the same population. Therefore, interventions at the breeder flock-level might help to reduce transmission of Salmonella from breeder flocks to hatcheries and possibly, to lower levels of the poultry production chain.
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