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Impact of age at first calving on reproduction, lactation, postpartum disorders and longevity in Holsteins under Egyptian circumstances
2009
M. M. Hussein | A. A. A. El Agawany
A retrospective study including reproductive and productive data of 1587 primiparous Holstein cows covering a period of eight years. The reproductive data ( interval to 1st service, service period, days open, number of inseminations per conception and calving interval ) and the productive data ( total milk yield, average daily milk yield and 305 day milk yield) were studied as a function of age at first calving and postpartum disorders. Furthermore, other data including life span longevity, number of parities, the cumulative productive days and the average calving interval were also studied as a function of age at first calving. Cows were classified according to the age at first calving into young age calvers (< 24 months), mid age calvers (> 24-28 months) and old age calvers (> 28 months). The obtained data were statistically analyzed, tabulated and discussed. The overall mean age at first calving was 26.68 months in Holstein cows under Egyptian circumstances. Most of first calving (90%) were recorded in cows less than 30 month of age. The results indicated that, the young age calvers tend to have prolonged interval to 1st service, days open and calving interval and the reverse was correct in old age calvers. The postpartum disorders had significantly detrimental effects on the reproductive performance among the different age groups. Young age calvers had a higher incidence of postpartum disorders than those of mid - age calvers and much higher than had the old age group. The postpartum disorders were associated with high milk production specially in mid and old age calvers which may indicate the high predisposition of superior producer cows to postpartum disorders. Life span, longevity, number of parities and the cumulative production days were found to be increased as a function of age at first calving. Meanwhile, the average calving interval of the young age calvers was longer than the other two age groups. Finally, it was recommended to avoid insemination of maiden Holstein heifers less than 17 month of age specially those having superior productive traits.
Show more [+] Less [-]Towards an improved estimate of antimicrobial use in animals: Adjusting the "population correction unit" calculation
2017
Radke, B. R.
International comparisons of animal antimicrobial use (AMU) have typically been based on total national estimates of antimicrobials sales standardized by the national animal biomass calculated as the population correction unit (PCU). The objective of this paper was to compare the currently accepted PCU calculation with that of the adjusted population correction unit (APCU), which re-evaluates the standard animal weights used in the calculation and accounts for animal lifespan. The APCU calculation resulted in substantial changes to the 2009 national biomass estimates for cattle, pigs, and poultry in 8 European countries and Canada. The estimated national biomass for cattle increased 35% to 43%, while the estimated national biomass of pigs and poultry typically decreased by approximately 51% and 87%, respectively. Among the 9 countries, the total national APCU ranged from an increase of 1% to a decrease of 40% relative to PCU, and these differences were statistically significant. Adjusted population correction unit is preferred over PCU in comparing and contrasting AMU among animals with different lifespans because it is more transparently derived and is a reasonable approximation of the animal biomass at risk of antimicrobial treatment.
Show more [+] Less [-]Racing performance of Standardbred trotting horses undergoing surgery of the carpal flexor sheath and age- and sex-matched control horses
2017
Carmalt, James L. | Johansson, Bengt C. | Zetterstrom, Sandra M. | McOnie, Rebecca C.
OBJECTIVE To determine factors affecting race speed in Swedish Standardbred horses undergoing surgery of the carpal flexor sheath (CFS), to investigate whether preoperative racing speed was associated with specific intraoperative findings and whether horses returned to racing, and to compare the performance of horses undergoing surgery of the CFS with that of age- and sex-matched control horses. ANIMALS 149 Swedish Standardbred trotters undergoing surgery of the CFS and 274 age- and sex-matched control horses. PROCEDURES Medical records of CFS horses were examined. Racing data for CFS and control horses were retrieved from official online records. Generalizing estimating equations were used to examine overall and presurgery racing speeds and the association of preoperative clinical and intraoperative findings with preoperative and postoperative speeds. Multivariable regression analysis was used to examine career earnings and number of career races. Kaplan-Meier survival analysis was used to compare career longevity between CFS and control horses. RESULTS CFS horses were significantly faster than control horses. The CFS horses that raced before surgery were slower as they approached the surgery date, but race speed increased after surgery. There were 124 of 137 (90.5%) CFS horses that raced after surgery. No intrathecal pathological findings were significantly associated with preoperative racing speed. Career longevity did not differ between CFS and control horses. CONCLUSIONS AND CLINICAL RELEVANCE Horses undergoing surgery of the CFS had a good prognosis to return to racing after surgery. Racing careers of horses undergoing surgery of the CFS were not significantly different from racing careers of control horses.
Show more [+] Less [-]Role of toll-like receptor 4 and caspase-3, -8, and -9 in lipopolysaccharide-induced delay of apoptosis in equine neutrophils
2018
Anderson, Stacy L. | Townsend, Hugh G. G. | Balajīta Siṅgha,
OBJECTIVE To evaluate the effect of lipopolysaccharide (LPS) on apoptosis of equine neutrophils in vitro. SAMPLE Venous blood samples from 40 adult horses. PROCEDURES Neutrophils were isolated from blood samples and cultured with or without LPS from Escherichia coli O55:B5 for 12 or 24 hours. Neutrophil apoptosis was assessed by use of cytologic examination, annexin V and propidium iodide staining quantified with flow cytometry, coincubation with inducers of intrinsic and extrinsic apoptosis or a toll-like receptor (TLR) 4 inhibitor, and measurement of caspase-3, -8, and -9 activities. RESULTS Treatment with LPS resulted in a significant delay in apoptosis after incubation for 12 and 24 hours (neutrophils from blood samples of 40 horses). There was a significant correlation between increases in LPS dose and decreases in apoptosis after incubation for 24 hours (3 experiments, each of which involved neutrophils obtained from the same 3 horses at 3 separate times). Caspase-9 activity, but not caspase-3 or -8 activity, was significantly reduced in LPS-treated neutrophils after incubation for 12 hours (neutrophils from blood samples of 17 horses). Treatment with a TLR4 inhibitor or intrinsic and extrinsic inducers of apoptosis prevented LPS-delayed apoptosis. CONCLUSIONS AND CLINICAL RELEVANCE LPS treatment delayed apoptosis of equine neutrophils in vitro for up to 24 hours in a dose-dependent manner by alteration of the intrinsic pathway of apoptosis and was dependent on TLR4 signaling. Increased neutrophil life span may contribute to the development of a systemic inflammatory response syndrome in endotoxemic horses.
Show more [+] Less [-]Longevity and productivity of Taenia taeniaeformis in cats
1981
Williams, J.F. | Shearer, A.M.
Taenia taeniaeformis, cats (exper.), parasite longevity and productivity
Show more [+] Less [-]Development of a biologically immortalized equine stem cell line
2021
Nino-Fong, Rodolfo | Esparza Gonzlaez, Blanca P. | Rodriguez-Lecompte, Juan Carlos | Montelpare, William | McDuffee, Laurie
Bone repair in horses implies invasive surgeries and increased cost. Research on musculoskeletal disorders therapy in horses includes cell-based therapy with mesenchymal stromal cells (MSCs). Mesenchymal stromal cells can be obtained from bone marrow (BMMSCs). Unfortunately, BMMSCs have limited cell replication in vitro. The objective of this study was to develop a biologically immortalized equine stem cell line derived from bone marrow, with unlimited in-vitro proliferation and the ability to differentiate into bone cells. Equine BMMSCs were transfected and immortalized with human telomerase reverse transcriptase (hTERT) gene. Cell passages from equine immortal BMMSCs were characterized by the presence of stemness CD markers and expression of multi-potent differentiation genes (OCT-4, SOX2, and NANOG). Equine immortal BMMSCs were incubated in osteogenic medium and bone cell differentiation was determined by alkaline phosphatase and von Kossa staining, and osteogenic gene expression (osteocalcin, Runx2, and osterix). Telomerase activity was determined by telomeric repeat amplification technique. Results showed that equine immortal BMMSCs were able to replicate in-vitro up to passage 50 and maintain stem cell characteristics by the presence of CD90 and expression of multi-potent genes. Equine immortal BMMSCs were able to differentiate into bone cells, which was confirmed by the positive osteogenic staining and gene expression. Equine BMMSCs were successfully immortalized and maintained characteristics of stem cells and readily differentiated into osteogenic cells. Extending the life span of equine BMMSCs by transfection of the hTERT gene will revolutionize the clinical use of MSCs by making them available to orthopedic surgeons "off the shelf."
Show more [+] Less [-]Life expectancy in a follow-up study of a birth cohort of boxer dogs from post weaning to 10-years of age
2005
Hagen, van, M.A.E. | Ducro, B.J. | Knol, B.W.
Objective-To determine mortality rate over time, risk factors for death, and heritability of life expectancy in Boxers. Animals-1,733 purebred Boxers born in The Netherlands between January 1994 and March 1995. Procedure-Dogs were followed up from weaning (ie, 49 days of age) to 10 years of age through use of a written questionnaire sent to owners every 6 months. Mortality rate over time, risk factors potentially associated with death, and heritability of life expectancy were examined by use of a proportional hazards model based on the Weibull distribution. Results Estimated mortality rate during the 10-year study period for this birth cohort of Boxers was 45%. The probability of surviving to 5 years of age was 88%; the probability of surviving to 10 years of age was 55%. Estimated effective heritability of life expectancy was 0.076, meaning that in this population, an estimated 76% of the observed variation in life expectancy could be attributed to genetic differences among dogs that were passed from parents to their offspring. Conclusions and Clinical Relevance-Results suggest that cumulative incidence of death from weaning to 10 years of age among this birth cohort of Boxers was 45%. The estimated heritability of life expectancy suggested that life expectancy can be improved by use of selective breeding.
Show more [+] Less [-]In vitro study of longevity of canine cauda epididymal spermatozoa.
2011
Swain, D. K. | Tarai, A. | Kundu, A.K.
The present study was designed to evaluate the longevity of canine cauda epididymal sperm in vitro at 40C. The testes were collected from 30 mixed breed dogs of average weight of 20-25Kg,presented to the clinics for sterilization. The testes were stored at 40C in normal saline in a refrigerator.The sperms were collected from the epididymis at different intervals of time (0, 4, 8, 12 and 24 hr) by taking 6 testes in each interval of time. The sperm quality was accessed at different intervals of time.The data analysed was analysed by ANOVA and the significant level was 5% (P= 0.05). The sperm concentration at different interval of time and storage at 40C did not show significant difference. On the other hand the sperm motility revealed significant difference between all the time intervals of sperm collection except at 8 and 12 hr of collection. There was significant difference of live sperm (%) at different intervals of sperm collection except at 8-12 hrs of sperm collection. The percentage of normal sperms was significantly different in between 0 to 24 hr interval of time but there was no significant difference either at 4 and 8hr or 12 and 24 hr of sperm collection. The acrosomal integrity was found statistically significant between 0-24 hrs of sperm collection and storage at 40C. There was significant difference in percentage of hypo- osmotic swelling between 0 hr (66.67 ± 2.11%), 4 hr (40.50 ± 6.21%), 8 hr (26.27 ± 2.25), 12 hr (11.50 ± 1.38%) and 24 hr (6.67 ± 1.05%). However, there was no difference between 8 and 12 hr of sperm collection from testes and storage at 40 C. The study concluded that the cauda epididdymal spermatozoa can be effectively stored and utilised for the purpose of assisted reproductive technology during emergency. These findings can be applied to the endangered wild canines and felines.
Show more [+] Less [-]Longevity and fecundity of Trichinella spiralis in mast cell-deficient S1/S1d mice
1987
Itayama, H. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Oku, Y. | Kamiya, M.
The gray matter: Prevention and reduction of abnormal behavior in companion gray parrots (Psittacus erithacus)
2017
Greenwell, Phillip J. | Montrose, V Tamara
Gray parrots (Psittacus erithacus) are popular companion birds, particularly noted for their ability to mimic human speech, their intelligence, and longevity. They are also prone to developing abnormal behaviors such as feather damaging behavior. This review explores the current available knowledge on gray parrots kept as companion birds with respect to behavioral problems and their management. The potential causes for the development of abnormal behaviors in this species are explored. Recommendations are made for future research, and advice is provided on the synthesis and application of available research to owners, breeders, and clinicians of gray parrots so that their well-being is maximized in captivity.
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