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Seasonal prevalence of gastrointestinal nematodes of beef calves grazed on irrigated pastures in the lower Sacramento Valley of California.
1988
Charles T.P. | Baker N.F.
The impact of traditional management on seasonal internal parasite burdens and productivity of indigenous Tswana goats in southern Botswana
2001
Nsoso, S.J. | Machete, J.B. | Molatole, M. | Ndebele, R.T | Lebani, N.N. | Chabo, R.G. | Kalake, A.M. | Jacyna, L. | Segadimo, B.W | Mine, O.M
Data collected monthly over a period of two years were live weight, packed cell volume (PCV), nematode faecal egg counts (FECs) and coccidial oocyst counts from faecal analyses for 100 mixed age (3-7 years) indigenous Tswana does. The aims of this experiment were to determine seasonal FECs and coccidial oocysts in these goats and quantify the relationships of these burdens to liveweight and PCV. FECs significantly (P < 0.05) varied with season, with the warmer seasons viz spring, summer and autumn having higher log (x + 1) parasite burdens than the cooler winter, while seasonal trends for coccidial oocysts were not obvious. PCV was also significantly (P< 0.05) lower in the warmer seasons than winter. FECs and coccidial oocysts in all seasons were less than the mean log (x + 1) of 3.3 inferred to reduce production in small stock. Correlation coefficients were strongly negative: -0.95 for FECs and liveweight and -0.84 for FECS and PCV, indicating that these worms had a negative impact on productivity. A further study should be conducted to quantify the effects of controlling these parasites during the warm seasons on productivity.
اظهر المزيد [+] اقل [-]Diversity of Salmonella serovars in feedyard and nonfeedyard playas of the Southern High Plains in the summer and winter
2004
Purdy, Charles W. | Straus, David C. | Clark, R Nolan
Objective-To compare Salmonella isolates cultured from feedyard and nonfeedyard (control) playas (ie, temporary shallow lakes) of the Southern High Plains. Sample Population-Water and muck (sediment) samples were obtained from 7 feedyard playas and 3 nonfeedyard playas in the winter and summer. Procedure-Each water and muck sample was enriched with sulfur-brilliant-green broth and incubated in a shaker at 37°C for 24 hours. A sample (100 mL) of the incubated bacterial-enriched broth was then mixed with 100 mL of fresh sulfur-brilliant-green enrichment broth and incubated in a shaker at 37°C for 24 hours. After the second incubation, a swab sample was streaked on differential media. Suspect Salmonella isolates were further identified by use of biochemical tests, and Salmonella isolates were confirmed and serovar determinations made. Results-Salmonella isolates were not recovered from the 3 control playas. Seven Salmonella enterica serovars were isolated from 5 of 7 feedyard playas in the summer, and 13 S enterica serovars were isolated from 7 of 7 feedyard playas in the winter. In the summer, 296 isolates were cultured, and 47 were Salmonella organisms. In the winter, 288 isolates were cultured, and 171 were Salmonella organisms. Conclusions and Clinical Relevance-Results indicated that feedyard playas are frequently contaminated with many Salmonella serovars. These pathogens should be considered whenever feedyard managers contemplate the use of water from these playas. Water from feedyard playas should not be used to cool cattle in the summer or for dust abatement.
اظهر المزيد [+] اقل [-]Effect of early lactation milk yield on reproductive disorders in dairy cows
1994
Grohn, Y.T. | Hertl, J.A. | Harman, J.L.
Association between individual cumulative milk yield and various reproductive disorders in 56,772 Finnish Ayrshire cows belonging to 5,912 herds in 80 communities was studied. All cows delivered calves between September 1985 and September 1986. Five logistic regression models were fitted, 1 for each outcome disorder of interest: early metritis, late metritis, silent heat, ovarian cyst, and other infertility. Cumulative individual 37-day milk yield was used in the early metritis model, and cumulative individual 60-day milk yield was used in the other models, on the basis of median days in milk when these disorders developed. Cumulative 305-day herd milk yield, parity, calving season, presence or absence of other disorders, and community were also included in the models. Point estimates from the models represented odds ratios for the likelihood of having the outcome disorder.Lactational incidence risks for the 5 reproductive disorders studied were: early metritis (2.4%), late metritis (1.1%), silent heat (5.4%), ovarian cyst (6.6%), and other infertility (2.1%). The risk of early metritis decreased with increasing 37-day milk yield. The risk of silent heat, ovarian cyst, and other infertility increased with increasing 60-day milk yield; 60-day milk yield had no effect on late metritis. The 305-day herd milk yield increased the risk of early metritis, ovarian cyst, and other infertility; it had no effect on late metritis or silent heat. Parity had an effect on all disorders, except late metritis. Cows that delivered calves during the colder, darker seasons of the year had a higher risk of reproductive disorders than did those that delivered calves at other times of the year. A number of other disorders, reproductive and otherwise, were significant predictors of development of the outcome disorders.
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]Mass screening of cattle sera against 14 infectious disease agents, using an ELISA system for monitoring health in livestock
1991
Behymer, D.E. | Riemann, H.P. | Utterback, W. | D-Elmi, C. | Franti, C.E.
Mass screening ELISA methods were developed for testing cattle serum for antibodies against 14 common livestock diseases simultaneously. The absorbance values were transformed to a % ELISA (spectrophotometric antibody end point) by a computer interfaced with a microplate reader. A histogram indicating a cutoff point and a report for the veterinarian also was generated. The computer program produced a print-out of the antibody profile for each animal tested, the antibody concentration against each disease, and a histogram (antibody profile) showing the prevalence of each disease in the herd. Serum samples were obtained from 1,953 cattle, including 880 dairy cattle from 10 herds and 1,073 beef cattle from 20 herds. These samples were obtained from June 1988 through June 1989. The highest antibody prevalence was against bluetongue virus. Of the 1,953 cattle tested, 1,223 (63%) were seropositive for bluetongue virus, including 502 (57%) of the dairy cattle and 721 (67%) beef cattle. Other antibody prevalences, in descending order, were: rotavirus (44%), Pasteurella spp (25%), Leptospira spp and Haemophilus spp (22%), Mycoplasma spp (18%), parainfluenza virus (17%), Campylobacter spp (16%), Anaplasma marginale (15%), bovine leukosis virus (13%), Brucella spp (8%), Mycobacterium paratuberculosis (8%), bovine viral diarrhea virus (3%), and infectious bovine rhinotracheitis virus (3%). Major differences in antibody prevalence between dairy and beef cattle were that only 4% of the dairy cattle were seropositive for A marginale, compared with 25% of the beef cattle, and conversely, 29% of the dairy cattle were seropositive for bovine leukosis virus, compared with 1% of the beef cattle. Further development of the ELISA is advocated for mass screening of livestock sera for the application in epidemiologic methods for disease control in food animals.
اظهر المزيد [+] اقل [-]Effects of age and season on the type and occurrence of sperm abnormalities in Nubian bucks
1988
Skalet, L.H. | Rodrigues, H.D. | Goyal, H.O. | Maloney, M.A. | Vig, M.M. | Noble, R.C.
Effects of age and season on type and occurrence of sperm abnormalities were examined in semen samples collected from 3 groups of Nubian bucks at ages of 4 to 9 months, 10 to 21 months, and 39 to 50 months. The average total percentage of sperm abnormalities at the onset of puberty (141 +/- 4 days) was 64.6 +/- 14.8% (head, 19.5 +/- 13.6%; middle piece, 17.2 +/- 9.3%; and proximal protoplasmic droplets, 14.6 +/- 10.5%), but this improved rapidly and was reduced to 12.5 +/- 7.5% by 8 months of age (head, 1.9 +/- 4.5%; middle piece, 4.6 +/- 2.8%). Further increase in age, at least up to 4 years, did not reveal a significant effect (P less than 0.05) on the type of percentage of total abnormalities. Similar to age, a comparison of data among seasons did not reveal a significant effect on the type or occurrence of sperm abnormalities in 10- to 21-month-old or 39- to 50-month-old bucks. Seemingly, Nubian bucks started producing good quality semen at 8 months of age, and season did not influence sperm abnormalities.
اظهر المزيد [+] اقل [-]Transmission of equine cyathostomes (Strongylidae) in central Texas
1983
Craig, T.M. | Bowen, J.M. | Ludwig, K.G.
strongyles (predominantly cyathostomes), mares and their foals, dynamics of transmission studied on pastures previously free of parasites, fecal egg counts beginning day of parturition and based on time of year, relationship between weather conditions and pasture larval counts, necropsy findings in two foals: Texas
اظهر المزيد [+] اقل [-]Parasites of domestic and wild animals in South Africa. XIV. The seasonal prevalence of Rhipicephalus sanguineus and Ctenocephalides spp. on kennelled dogs in Pretoria North
1982
Horak, I.G.
Rhipicephalus sanguineus and Ctenocephalides spp. on kennelled dogs, seasonal prevalence and mean numbers and percentages of immature and adult ticks and of fleas recovered from various sites on dogs
اظهر المزيد [+] اقل [-]Parafilaria bovicola (Tubangui 1934) in cattle: Epizootiology--disease occurrence
1982
Bech-Nielsen, S. | Sjogren, U. | Lundquist, H.
Parafilaria bovicola, cattle, epizootiology, results of questionnaire survey among cattle owners revealed that (i) condemnation losses due to parasite were overrepresented among animals that came from herds held on pasture the previous year, as opposed to those from farms with indoor cattle management only; (ii) statistically significant difference between affected and nonaffected herds with respect to age groups; and (iii) frequency of lesions showed seasonal trend: Sweden
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