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61.
62.
The objective of this study was to investigate the impact of paratuberculosis sero-status on milk yield, fat, protein, somatic cell count and calving interval in Irish dairy herds. Serum from all animals over 12 months of age (n = 2,602) in 34 dairy herds was tested for antibodies to Mycobacterium avium subsp. paratuberculosis using an ELISA. Herds were categorised by sero-status into positive, non-negative and negative, where a positive herd contained two or more positive cows, a non-negative herd contained only one positive cow and a negative herd contained no positive cows. Data at animal, parity and herd-level were analysed by multiple regression using general linear models. Positive herds (mean herd size = 129 cows) and non-negative herds (81 cows) were larger than negative herds (72 cows) (P < 0.01). Negative herds had the highest economic breeding index (EBI), while positive herds had the highest estimated breeding value (EBV) for milk yield. There was no significant effect of paratuberculosis sero-status at animal, parity or herd-level on milk yield, milk fat or protein production, somatic cell count score (SCCS) or calving interval. Negative herds tended to have a lower SCCS than positive and nonnegative herds (P = 0.087). This study only examined the effects of paratuberculosis sero-status but did not examine the clinical effects of Johne's disease at the farm or dairy industry levels. 相似文献
63.
Marsha I. Sheppard D. H. Thibault Jude McMurry P. A. Smith 《Water, air, and soil pollution》1995,83(1-2):51-67
Iodine-129 is an important radionuclide released from nuclear facilities because of its long radioactive half-life and its environmental mobility. Its retention in surface soils has been linked to pH, organic matter, and Fe and Al oxides. Its inorganic solution chemistry indicates I will most likely exist as an anion. Three investigations were carried out to provide information on the role of the inorganic and organic chemistry during sorption of I by soil. Anion competition using Cl? showed that anion exchange plays a role in I sorption in both mineral and organic soils. The presence of Cl decreased the loss of I? from solution by 30 and 50% for an organic and a carbonated sandy soil respectively. The I remaining in solution was associated primarily with dissolved organic carbon (DOC). The loss rate from solution appears to depend on two reactions of I with the soil solids (both mineral and organic) creating both a release to and a loss from solution, and the reaction of I with the DOC (from very low to high molecular weight). Composition analyses of the pore water and the geochemical modelling indicate that I sorption affects the double-charged anion species in solution the most, particularly SO4 ?. Iodide introduced to natural bog groundwater at three concentrations (10?3, 10?1 and 10 meq L?1) remained as I? and was not lost from solution quickly, indicating that the association of I with DOC is slow and does not depend on the DOC or I concentration. If sorption of I to soil solids or DOC is not sensitive to concentration, then stable I studies, which by necessity must be carried out at high environmental concentrations, can be linearly extrapolated to radioactive I at much lower molar concentrations. 相似文献
64.
This study examined how muscle metabolic organization varied during an annual cycle in which rainbow trout (Oncorhynchus mykiss) were held in outdoor holding ponds in which they were exposed to natural changes in temperature (range 0.2 to 15.6°C) and
photoperiod. We examined the activities of glycolytic and mitochondrial enzymes in red and white muscle to evaluate whether
trout enhance their capacity for lipid and carbohydrate oxidation during cold-acclimization. When assayed at habitat temperature,
the enzyme activities generally increased in spring to reach a maximum in summer followed by a decrease in the fall. This
led to significantly higher activities at warm than cold periods for all enzymes measured in red muscle and all but one in
white muscle. The activities at 10°C provided little evidence for compensatory adjustments of aerobic capacity. Particularly
in red muscle, enzyme levels at 10°C were generally lower during cold than warm periods. The variation of enzyme activities
throughout the cycle was not due to changes in protein concentration, as the same responses were observed when activities
were expressed per g wet mass or per mg protein. Although the aerobic capacity did not increase with cold-acclimatization,
the relative capacity for lipid oxidation was higher in winter than in summer trout. In contrast, the relative capacity for
aerobic glycolysis was higher in summer than in winter trout. Thus, the metabolic capacities of trout muscle undergo seasonal
reorganization. 相似文献
65.
I García‐Ispierto S Almería B Serrano NM de Sousa JF Beckers F López‐Gatius 《Reproduction in domestic animals》2013,48(4):613-618
The present study sought to determine: (i) the effects of Neospora caninum infection and twin pregnancy on plasma pregnancy‐associated glycoprotein‐2 (PAG‐2) concentrations throughout pregnancy and (ii) whether plasma PAG‐2 concentrations could predict abortion in N. caninum‐infected cows. The study was performed on a commercial Holstein‐Friesian dairy herd in northeastern Spain and the final data included those recorded in 53 non‐aborting and 19 aborting animals. Blood samples were collected immediately before pregnancy diagnosis (on Days 40, 90, 120, 150, 180 and 210 post‐insemination) in non‐aborting cows or until the time of abortion detection in aborting cows. General lineal models (GLM) repeated measures anova revealed the different behaviour of PAG‐1 and PAG‐2, and significant effects of Neospora seropositivity, cool season and twin pregnancy on plasma PAG‐2 concentrations throughout gestation (between‐subject effects). In addition, based on the odds ratios, the likelihood of abortion increased in Neospora‐seropositive cows (by a factor of 7.0) compared to seronegative animals and decreased in cows with a high plasma PAG‐2 concentration (>4.5 ng/ml) on Day 120 of pregnancy (by a factor of 0.24), compared to the remaining cows. In conclusion, there is a relationship between plasma PAG‐2 concentrations and the risk of abortion in Neospora‐infected dairy cows. Thus, plasma PAG concentrations measured using anti‐boPAG‐2 antiserum on Day 120 of gestation could serve as an indicator of the abortion risk in N. caninum infected animals; values <4.5 ng/ml indicating a high risk of abortion in chronically infected animals. 相似文献
66.
The objective of the present study was to elicit opinion from two groups of veterinarians [subject matter experts and non‐subject matter experts] about the causes of bovine perinatal mortality and the criteria used to assign such causes. The subject matter experts were selected on the basis of their scientific publications or experience of working in a veterinary diagnostic or research laboratory in the area of bovine perinatal mortality. The non‐subject matter experts were self‐selected as cattle veterinarians without particular expertise in bovine perinatology. A total of 74 veterinarians (46 subject matter experts and 28 non‐subject matter experts) from 23 countries responded. The study was conducted using Delphi methodology over seven rounds. Respondents were asked to agree the causes of bovine perinatal mortality and for each cause to agree the supporting diagnostic criteria. There was a close agreement between groups on 16 causes of death apart from intra‐uterine growth retardation (IUGR) and micronutrient imbalances which were accepted by fewer subject matter experts. There was inter‐group consensus on the criteria to diagnose accidents, congenital defects, dystocia, hyperthermia, infections, premature placental separation, prematurity and prolonged calving. There was inter‐group consensus on the criteria to diagnose anoxia, apart from gingival cyanosis; on haemorrhage, apart from haemorrhagic anaemia; on IUGR, apart from organ weights; and on iodine imbalance, apart from goitre and thyroid iodine content. The results from this study highlighted the current lack of standardization of the criteria used to define the cause of death for bovine perinatal mortality and the need for such standardization. 相似文献
67.
A Torres JF Silva N Bernardes J Sales Luís L Lopes da Costa 《Reproduction in domestic animals》2013,48(3):e33-e37
Here is reported a disorder of sex development found in the Portuguese Lusitano horse breed. The complex genital phenotype included mammary glands, abdominal testes without epididymis, connected through oviducts to pelvic hypoplastic uterine horns and fused vulvar labia majora from which protruded ventrally a penis‐like structure. This structure was presented in a reversed position, the urethral opening placed dorsally in the glans. However, it was functional both for micturition and erection. The horse exhibited female micturition posture and aggressive male‐like behaviour, including flehmen, mounting, thrusting and flagging of the tail. Plasma testosterone concentrations were below detection limits and the genetic evaluation revealed a 64, XX, SRY‐negative karyotype. Surgery consisted in the removal of abdominal gonads followed by amputation of the penis and repositioning of the urethra. This case of reversion between the chromosomal and gonadal sex, associated with mixed anatomical and behavioural phenotype, illustrates that development of the testes may occur in the absence of the SRY gene and that other genetic and cellular pathways leading to gonad differentiation should be investigated. 相似文献
68.
A Grinberg WE Pomroy JF Weston A Ayanegui-Alcerreca D Knight 《New Zealand veterinary journal》2013,61(5):315-320
AIM: To determine the occurrence of Cryptosporidium parvum oocysts, Campylobacter spp and Salmonella spp in faecal samples taken from newborn dairy calves on 24 dairy farms in the Manawatu region of New Zealand. METHODS: A cross-sectional study was conducted during the 2002 calving season. Faecal samples were collected from 185 newborn calves from a convenience sample of 24 dairy farms. The samples were tested microscopically for the presence of C. parvum oocysts, and bacteriologically for the presence of Campylobacter spp and Salmonella spp. RESULTS: Infections with C. parvum were identified in 33/156 (21.2%) calves from 10 farms. More than 106 oocysts/g (OPG) faeces were detected in calves from four farms. Campylobacter spp were isolated from 58/161 (36%) calves from 18 farms; in particular, C. jejuni subsp jejuni was isolated from 11/161 (6.8%) calves from seven farms. Salmonellae were not detected. CONCLUSIONS: Despite the short and concentrated calving pattern and the long interval between calving seasons characterising most dairy farms in New Zealand, C. parvum is widespread among calves. Campylobacter spp, especially C. jejuni, rapidly colonise the intestinal tract of newborn calves. RELEVANCE: This study provided an estimate of the ecological impact of newborn dairy calves with regard to the potentially zoonotic enteric pathogens most frequently isolated from human gastrointestinal infections in New Zealand. 相似文献
69.
R Kasimanickam JB Hall JF Currin B Inman JS Rudolph WD Whittier 《Reproduction in domestic animals》2010,45(3):487-492
Crossbred cows (n = 1073) from five locations had oestrous cycles synchronized with 100 μg of GnRH IM and insertion of controlled internal drug release device (CIDR) on Day 0 followed by 25 mg of PGF2α IM and CIDR removal on Day 7. Kamar® patches were placed on all cows at CIDR removal. Cows were observed three times daily for oestrus after PGF2α administration. In the Ovsynch‐CIDR group, cows detected in oestrus (n = 193) within 48 h after PGF2α were inseminated using the AM–PM rule. Among these cows, 80 received and 113 did not receive a second GnRH at 48 h after PGF2α. Cows (n = 345) not detected in oestrus received a second GnRH at 48 h after PGF2α on Day 9, and fixed‐time AI 16 h after the GnRH on Day 10. In the CO‐Synch‐CIDR group, cows detected in oestrus (n = 224) within 48 h after PGF2α were inseminated using the AM–PM rule. Among these cows, 79 received and 145 did not receive a second GnRH at 64 h after PGF2α. Cows (n = 311) not detected in oestrus received a second GnRH on Day 10 at the time of AI, 64 h after PGF2α. The AI pregnancy rates were not different between the Ovsynch‐CIDR and CO‐Synch‐CIDR groups (p = 0.48). There were no differences in the AI pregnancy rates for cows inseminated at a fixed time (p = 0.26) or at detected oestrus (p = 0.79) between the treatment groups. Among cows inseminated in oestrus, there were no differences in the AI pregnancy rates between cows that received or did not receive the second GnRH (p = 0.47). In conclusion, acceptable AI pregnancy rates can be achieved with or without inclusion of oestrus detection in the Ovsynch‐CIDR and CO‐Synch‐CIDR protocols. Among cows detected in oestrus, cows that received a second GnRH yielded similar pregnancy rates when compared with cows that did not receive the second GnRH. 相似文献
70.
Guangling Jiao Joseph P. M. Hui Ian W. Burton Marie-Hélène Thibault Claude Pelletier Josée Boudreau Nadia Tchoukanova Balaji Subramanian Yahia Djaoued Stephen Ewart Jacques Gagnon Kathryn Vanya Ewart Junzeng Zhang 《Marine drugs》2015,13(6):3849-3876
Northern shrimp (Pandalus borealis) oil, which is rich in omega-3 fatty acids, was recovered from the cooking water of shrimp processing facilities. The oil contains significant amounts of omega-3 fatty acids in triglyceride form, along with substantial long-chain monounsaturated fatty acids (MUFAs). It also features natural isomeric forms of astaxanthin, a nutritional carotenoid, which gives the oil a brilliant red color. As part of our efforts in developing value added products from waste streams of the seafood processing industry, we present in this paper a comprehensive characterization of the triacylglycerols (TAGs) and astaxanthin esters that predominate in the shrimp oil by using HPLC-HRMS and MS/MS, as well as 13C-NMR. This approach, in combination with FAME analysis, offers direct characterization of fatty acid molecules in their intact forms, including the distribution of regioisomers in TAGs. The information is important for the standardization and quality control, as well as for differentiation of composition features of shrimp oil, which could be sold as an ingredient in health supplements and functional foods. 相似文献