خيارات البحث
النتائج 1 - 10 من 21
Age-related changes in carbohydrate tolerance in healthy neonatal calves.
1986
Rollin R.E. | Fettman M.J. | Phillips R.W.
Effects of ketosis in dairy cows on blood biochemical parameters, milk yield and composition, and digestive capacity النص الكامل
2019
Yang, Wei | Zhang, Bingbing | Xu, Chuang | Zhang, Hongyou | Xia, Cheng
Effects of ketosis in dairy cows on blood biochemical parameters, milk yield and composition, and digestive capacity النص الكامل
2019
Yang, Wei | Zhang, Bingbing | Xu, Chuang | Zhang, Hongyou | Xia, Cheng
This study aimed to characterise the effects of ketosis on milk yield and composition and digestive capacity in transition dairy cows. Seven ketotic and seven healthy cows were housed in individual stalls for six days. Samples of plasma, milk, refused total mixed ration, and faeces were collected, and the blood biochemical parameters, milk yield and composition, dry matter intake, and faecal dry matter (FDM) production were determined. Compared with healthy cows, the ketotic cows had significantly higher concentrations of milk fat and citrate, but lower levels of milk protein and lactose. The cows exhibited a need for acid detergent fibre in forage and better digestion of neutral detergent fibre, starch, crude protein, and phosphorus than healthy cows, but more fat and gross energy were excreted in their faeces. Ketotic cows had higher energy-corrected milk yields and lower FDM than healthy cows. Lower feed intake coinciding with the requirement to maintain high milk production is considered to be the cause of ketosis in dairy cows. Ketotic cows exhibited lower dry matter fat digestion.
اظهر المزيد [+] اقل [-]Effects of ketosis in dairy cows on blood biochemical parameters, milk yield and composition, and digestive capacity النص الكامل
2019
Yang Wei | Zhang Bingbing | Xu Chuang | Zhang Hongyou | Xia Cheng
This study aimed to characterise the effects of ketosis on milk yield and composition and digestive capacity in transition dairy cows.
اظهر المزيد [+] اقل [-]Effects of orally administered raltegravir in cats with experimentally induced ocular and respiratory feline herpesvirus-1 infection النص الكامل
2019
Spertus, Chole B. | Pennington, Matthew R. | Van de Walle, Gerlinde R. | Badanes, Zachary I. | Judd, Bonnie E. | Mohammed, Hussni O. | Ledbetter, Eric C.
OBJECTIVE To determine the effects of orally administered raltegravir in cats with experimentally induced ocular and respiratory feline herpesvirus-1 (FHV-1) infection. ANIMALS 14 healthy 6-month-old unvaccinated specific pathogen–free cats. PROCEDURES On day 0, all cats were experimentally inoculated by topical application of 0.1 mL of a solution containing 106 plaque-forming units of FHV-1 strain FH2CS to the inferior conjunctival fornix of each eye. Cats were randomly assigned to receive either raltegravir (80 mg; n = 7) or lactose (250 mg; vehicle; 7), PO, every 12 hours for 14 days beginning on day 1. Cats were assigned clinical ocular and respiratory disease scores every other day from days 0 to 30. Conjunctival swab specimens were collected for detection of FHV-1 by virus isolation and real-time PCR assay at 3-day intervals from days 0 to 30. Confocal microscopy was performed on days 0 and 10 to assess corneal epithelial leukocyte infiltration. The assessed variables and duration of FHV-1 shedding were compared between the 2 treatment groups. RESULTS Cats in both groups developed moderate to severe conjunctivitis and ulcerative keratitis characteristic of FHV-1 infection. Median duration of FHV-1 shedding was shorter and signs of ocular and respiratory disease were less severe for raltegravir-treated cats than for vehicle-treated cats. However, the mean conjunctival FHV-1 titer and corneal epithelial leukocyte count did not differ between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested orally administered raltegravir might be effective for alleviation of ocular and respiratory signs of FHV-1 infection in cats.
اظهر المزيد [+] اقل [-]Effect of orally administered melatonin on intraocular pressure of ophthalmologically normal dogs النص الكامل
2019
Visser, Hannah E. | Dees, D Dustin | Millichamp, Nicholas J. | Vallone, Lucien V. | Scott, Erin M.
OBJECTIVE To determine the effect of orally administered melatonin on the intraocular pressure (IOP) of ophthalmologically normal dogs. ANIMALS 20 ophthalmologically normal dogs (40 eyes). PROCEDURES In a randomized crossover study, each dog received a 7-day regimen of melatonin (0.1 to 0.2 mg/kg, PO, q 12 h) and a placebo (150 mg of lactose powder in a capsule, PO, q 12 h), with a 7-day washout period between treatment regimens. Rebound tonometry was used to measure the IOP in both eyes of each dog 5 times at 2-hour intervals on days 0 (before administration of the first dose), 2, 4, and 7 (after administration of the last dose) of each treatment period. Repeated-measures ANOVA was used to evaluate the effects of treatment, day, and IOP measurement time within day on IOP. RESULTS Intraocular pressure was not significantly associated with treatment but was associated with day and the interaction between day and IOP measurement time within day. The mean ± SD IOP was 14.26 ± 2.95 and 14.34 ± 2.69 mm Hg for the melatonin and placebo regimens, respectively. Within each treatment period, the mean IOP tended to decrease from day 0 to 7 as well as within each day, which was attributed to the dogs becoming acclimated to the study protocol and natural diurnal variations in IOP. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that oral administration of melatonin (0.1 to 0.2 mg/kg, q 12 h for 7 d) did not significantly affect the IOP of ophthalmologically normal dogs.
اظهر المزيد [+] اقل [-]Effect of oral administration of meloxicam prior to transport on inflammatory mediators and leukoctye function of cattle at feedlot arrival النص الكامل
2017
Capik, Sarah F. | White, Brad J. | Larson, Robert L. | Van Engen, Nicholas | Cernicchiaro, Natalia | Engelken, Terry J. | Lakritz, Jeffrey | Ballou, Michael A. | Hulbert, Lindsey E. | Vann, Rhonda C. | Caswell, Jeff L. | Jacob, Gabriella | Carroll, Jeffery A. | Coetzee, Johann F.
OBJECTIVE To investigate the effects of meloxicam administration before long-distance transport on inflammatory mediators and leukocyte function of cattle at feedlot arrival. ANIMALS 60 healthy yearling beef steers. PROCEDURES Single-source steers were assigned to a transported (n = 40) or nontransported (20) group. Then, half of the steers within each group were assigned to receive meloxicam (1 mg/kg, PO) or a lactose placebo (1 bolus/steer, PO). All steers were transported approximately 1,300 km overnight to a feedlot; however, the nontransported group was moved before treatment (meloxicam or placebo) administration and allowed a 17-day acclimation period, whereas the transported group was moved immediately after treatment administration on day −1. Blood samples for measurement of inflammatory mediators and leukocyte function were collected from all steers on days −1, 0, and 3. RESULTS For steers that received meloxicam, mean plasma meloxicam concentration for the transported group was significantly greater than that for the nontransported group on day 0. For steers that received the placebo, mean haptoglobin-matrix metalloproteinase-9 complex for the transported group was significantly greater than that for the nontransported group on day 0. Mean haptoglobin concentration, neutrophil L-selectin intensity, and polymorphonuclear leukocyte count for the transported group were significantly greater than those for the nontransported group. Mean substance P concentration for nontransported steers that received meloxicam was significantly lower than that for the other 3 treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated meloxicam administration to healthy steers immediately before long-distance transport did not significantly mitigate the effects of transport-induced stress on leukocyte function or inflammatory markers.
اظهر المزيد [+] اقل [-]A meta-analysis review of the effects of recombinant bovine somatotropin. 1. Methodology and effects on production النص الكامل
2003
Dohoo, I.R. | Leslie, K. | DesCôteaux, L. | Fredeen, A. | Dowling, P. | Preston, A. | Shewfelt, W.
This manuscript presents the results of a review of the effects of recombinant bovine somatotropin (rBST) on milk production, milk composition, dry matter intake, and body condition score that was carried out by an expert panel established by the Canadian Veterinary Medical Association (CVMA). The panel was established by the CVMA in response to a request from Health Canada in 1998 and their report was made public in 1999. A series of meta-analyses was used to combine data on production and nutrition related parameters that were extracted from all randomized clinical trials, which had been published in peer-reviewed journals or which were provided by Health Canada, from the submission by Monsanto for registration of rBST in Canada. A companion paper will present the results of the effects of the drug on measures of health, reproductive performance, and culling parameters. Recombinant bovine somatotropin was found to increase milk production by 11.3% in primiparous cows and 15.6% in multiparous cows; although there was considerable variation from study to study. While some statistically significant effects on milk composition (% butterfat, protein, and lactose) were found, they were all very small. Treatment increased dry matter intake by an average 1.5 kg/day during the treatment period and dry matter intake remained elevated on into the first 60 days of the subsequent lactation. Despite the increase in dry matter intake, treated animals had lower body condition scores at the end of the treatment period, and the reduced scores persisted through until the start of the subsequent lactation.
اظهر المزيد [+] اقل [-]Jejunal mucosal lactase activity from birth to three weeks in conventionally raised calves fed an electrolyte solution on days 5, 6 and 7 instead of milk
1991
St Jean, G.D. | Schmall, L.M. | Rings, D.M. | Hoffsis, G.F. | Hull, B.L.
The purpose of this study was to evaluate the effect of withdrawal of lactose from the diet for 72 hours on lactase activity in the jejunal mucosa of conventionally raised calves. The descending portion of the duodenum of six Holstein calves < 24 hours old was cannulated. The calves were fed milk except on days 5, 6 and 7 when they were given the same volume of an electrolyte solution. Sequential biopsy specimens of the proximal jejunal mucosa were obtained for three weeks and the lactase activity determined. Lactase activity was highest on day 1 and a trend toward decreased lactase activity from birth until three weeks was observed. Mean lactase activity was significantly (p < 0.05) higher for days 1, and 3 compared to days 9, 13 and 17. The withdrawal of milk and replacement by an electrolyte solution during three days had no significant effect on jejunal mucosal lactase activity in neonatal calves.
اظهر المزيد [+] اقل [-]Influence of variation in spray-dried lactose quality on in vitro dissolution and bioavailability of an experimental oxfendazole bolus for cattle
1982
Shastri, S. | Hegde, G. | Mroszczak, E. | Herschler, R.
oxfendazole bolus for cattle, spray-dried lactose quality as influencing in vitro dissolution and bioavailability
اظهر المزيد [+] اقل [-]Effect of metoclopramide treatment of bitches during the first week of lactation on serum prolactin concentration, milk composition, and milk yield and on weight gain of their puppies النص الكامل
2018
Keller, Stefanie R. | Abonyi-Toth, Zsolt | Sprenger, Norbert | Austin, Sean C. | Wichert, Brigitta A. C. | Liesegang, A. (Annette) | Oei, Christine H. Y. | Balogh, Orsolya | Reichler, Iris M.
OBJECTIVE To investigate effects of metoclopramide orally administered to healthy bitches on serum prolactin and milk lactose concentrations, gross energy, and dry matter content and on puppy weight gain during early lactation. ANIMALS 20 client-owned bitches and their 121 puppies. PROCEDURES 10 bitches received metoclopramide (0.2 mg/kg, PO, q 6 h for 6 days; treatment group) starting 10 to 24 hours after birth of the last puppy of the litter (day 0), and 10 bitches served as the control group. Blood and milk samples from all bitches were collected on days 0, 1, 2, 4, and 6. Milk samples for days 1 and 2 and days 4 and 6 were pooled because of small volume. Puppies were weighed twice daily. RESULTS Serum prolactin concentration increased significantly over time in both groups, and no treatment effect was detected. When day-to-day changes were analyzed, the prolactin concentration increased from day 0 to day 1 in the treatment group but not in the control group. Milk lactose concentration increased significantly and was higher in the treatment group than in the control group. Milk dry matter content was unchanged, whereas the time course for milk gross energy content differed significantly between treatment and control bitches. Puppy weight gain was not affected by metoclopramide treatment. CONCLUSIONS AND CLINICAL RELEVANCE Oral administration of metoclopramide to healthy bitches after parturition induced a transient increase in serum prolactin concentration and stimulated milk lactose production. It is likely bitches with insufficient or delayed milk production could benefit from metoclopramide treatment.
اظهر المزيد [+] اقل [-]Effects of synbiotics injected in ovo on regulation of immune-related gene expression in adult chickens النص الكامل
2014
Sławińska, Anna | Siwek, Maria | Bednarczyk, Marek F.
Objective—To determine immunomodulatory effects of synbiotics administered in ovo on immune-related gene expression in adult chickens. Animals—30 Green-legged Partridgelike chickens. Procedures—On incubation day 12, eggs were injected with 3 synbiotics (Lactococcus lactis subsp lactis IBB SL1 with raffinose family oligosaccharides [RFOs; S1], Lactococcus lactis subsp cremoris IBB SC1 with RFOs [S2], and Lactobacillus acidophilus and Streptococcus faecium with lactose [S3]). Control eggs were injected with RFOs prebiotic or saline (0.9% NaCl) solution. Gene expression of 6 cytokines (interleukin [IL]-4, IL-6, IL-12p40, IL-18, interferon [IFN]-β, and IFN-γ) and 1 chemokine (IL-8) was analyzed in the cecal tonsils and spleen of 6-week-old chickens by means of reverse transcription quantitative PCR assays. Results—Gene expression for IL-4, IL-6, IFN-β, and IL-18 was significantly upregulated in the spleen of chickens in groups S2 and S3. In contrast, IL-12 expression was downregulated in group S2 and IFN-γ expression was downregulated in group S3. Expression of IL-8 did not change in chickens treated with synbiotics in ovo. Gene expression of all cytokines, except for IL-18, was downregulated in cecal tonsils. Conclusions and Clinical Relevance—In ovo administration of synbiotics activated the immune system in adult chickens. The intestinal immune system (cecal tonsils) had downregulation of expression for the cytokines evaluated, which indicated an increase in oral tolerance, whereas in the peripheral part of the immune system (spleen), expression of IL-4 and IL-6 was upregulated. Evaluation of immune-related gene expression patterns may be useful when monitoring the effectiveness of synbiotic selection with respect to immunobiotic properties.
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