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PubMed2003

Replacement value of undecorticated sunflower meal as a supplement for milk production by crossbred cows and buffaloes in the northern plains of India.

The replacement value of undecorticated sunflower meal (SFM) in the diets of dairy animals was assessed on-station and on-farm. Eighteen primiparous crossbred (Bos taurus x Bos indicus) cows (350.4 +/- 8.84 kg), randomly allocated to three groups, were used in the on-station study. The animals were fed on either a conventional concentrate supplement (control) or on an experimental concentrate, in which SFM replaced 25% (SFM-25) or 50% (SFM-50) of the CP in the control supplement. Green oats (Avena sativa) were supplied ad libitum. A metabolism trial conducted following 60 days of experimental feeding revealed that the intakes of DM, DCP and TDN were similar among the groups. The digestibilities of OM, CP, EE, NDF and ADF were also without significant differences. All the groups were in positive nitrogen balance. Inclusion of SFM at either level had no effect on the intake, excretion or retention of nitrogen. The daily milk yield and its composition did not differ among the dietary treatments. Moreover, the efficiency of utilization of DOM and TDN for FCM production tended to reflect, although non-significantly, increasing levels of SFM inclusion. In the on-farm study, seven multiparous milking buffaloes belonging to six farmers were used to assess the effect of replacing 20% of the CP of the conventional supplement with SFM, in a predominantly crop residue-based diet. The study continued for 4 months and revealed that the average daily feed intake and milk production was similar in the control and SFM-fed groups. It was concluded that SFM can be effectively utilized as a cheaper replacement for costly oil cakes and wheat bran for economic milk production by smallholder farmers.

Animals↗

PubMed2003

Use of a polymeric device to deliver growth factors to a healing fracture.

BACKGROUND: Fracture healing is a cascade of events regulated by systemic and local factors. Local growth factors are believed to play an integral role. The present study evaluates the effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor-1 (IGF-1) using a controlled delivery system in a closed rodent femoral fracture model. METHODS: Female Wistar rats (n = 144) were used in the present study. Animals were randomly allocated to six groups, with each group divided into three time-points of 2, 4 and 8 weeks. Two groups had growth factor administered. The others had no operation or sham operations. Growth factors were delivered to the fracture site using a specialised delivery system. This consisted of a Kirschner-wire coated with ethylene vinyl acetate co-polymer embedded with growth factors, inserted as an intramedullary nail. Fractures were effected with a three-point bending device. Femurs were tested in four-point bending and structural properties of peak load and stiffness were obtained from the load-displacement graphs. Specimens were prepared for qualitative analysis under a light microscope and using immunohistochemistry, specimens were analysed for expression of bFGF, IGF-1 and transforming growth factor beta (TGF-beta). RESULTS: The growth factor-treated groups exhibited larger calluses at 2 and 4 weeks. Four-point bending showed weaker structural properties (stiffness and peak load) at 4 weeks in both growth factor-treated groups. Administration of bFGF or IGF-1 increased the ratio of cartilaginous to mesenchymal tissues in the fracture callus compared with non-treated animals at 2 and 4 weeks. Immunostaining intensity and distribution of both growth factors in the treated groups was greater than the non-treated groups. CONCLUSION: Exogenous delivery of bFGF or IGF-1 alters the course of fracture healing.

Animals↗

PubMed2003

The soya isoflavone content of rat diet can increase anxiety and stress hormone release in the male rat.

RATIONALE: Most commercial rodent diets are formulated with soya protein and therefore contain soya isoflavones. Isoflavones form one of the main classes of phytoestrogens and have been found to exert both oestrogenic and anti-oestrogenic effects on the central nervous system. The effects have not been limited to reproductive behaviour, but include effects on learning and anxiety and actions on the hypothalamo-pituitary axis. It is therefore possible that the soya content of diet could have significant effects on brain and behaviour and be an important source of between-laboratory variability. OBJECTIVES: To determine whether behaviour in two animal tests of anxiety, and stress hormone production, would differ between rats that were fed a diet which was free of soya isoflavones and other phytoestrogens (iso-free) and those that were fed a diet which contained 150 microg/g of the isoflavones genistein and daidzein (iso-150). This controlled diet has an isoflavone concentration similar to that in the maintenance diet routinely used in our institution. METHODS: Male rats were randomly allocated to the iso-free and iso-150 diets and their body weights and food and water consumption were recorded for 14 days. They were then maintained on the same diets, but housed singly for 4 days, before testing in the social interaction and elevated plus-maze tests of anxiety. Corticosterone concentrations in both dietary groups were determined under basal conditions and after the stress of the two tests of anxiety. Vasopressin and oxytocin concentrations were determined after brief handling stress. RESULTS: The groups did not differ in food or water intake, body weight or oxytocin concentrations. Compared with the rats fed the iso-free diet, the rats fed the iso-150 diet spent significantly less time in active social interaction and made a significantly lower percentage of entries onto the open arms of the plus-maze, indicating anxiogenic effects in both animal tests. The groups did not differ in their basal corticosterone concentrations, but the iso-150 group had significantly elevated stress-induced corticosterone concentrations. Stress-induced plasma vasopressin concentrations were also significantly elevated in the iso-150 diet group compared with the iso-free rats. CONCLUSIONS: Major changes in behavioural measures of anxiety and in stress hormones can result from the soya isoflavone content of rat diet. These changes are as striking as those seen following drug administration and could form an important source of variation between laboratories.

Animals↗

PubMed2005

The enhancing effects of a chicken-meat extract on serum Ig concentrations in normal and scalded animals.

The aim of the study was to investigate the effects of a chicken-meat extract known as Essence of Chicken (EOC) on immune function in a normal and scalded animal model. In this experimental study, 120 rats were randomly allocated into three groups: a SHAM group (inflicted with a sham wound), a BURN group (inflicted with a full-thickness scald wound covering 30 % of total body surface area) and a CONTROL group. Rats in the SHAM and BURN groups were further divided into normal saline (NS)-fed and EOC-fed groups. They were fed by force-feeding with a feeding needle and blood samples were taken from each group on days 1, 8, 15 and 22 postburn. Serum IgG, IgA and IgM concentrations were determined by ELISA and the results of the EOC-fed and NS-fed cohorts of both the SHAM and BURN groups were compared. The level of significance was set at P<0.05. Serum IgG level of both SHAM-EOC and BURN-EOC cohorts showed significant elevation on day 8. IgA exhibited a significant increase in the SHAM-EOC group on day 15 and in the BURN-EOC group on day 22. A significant increase of IgM level was found on days 1 and 22 for the SHAM-EOC group and on day 15 for the BURN-EOC group. Conclusively, EOC was shown to have an enhancing effect on serum Ig levels for both normal and tissue-stressed rats. It is suggested that EOC may help improve immune function when the immune system is at normal status or when it faces a challenge.

Animals↗

PubMed2004

Effects of an injectable trace mineral supplement on first-service conception rate of dairy cows.

A total of 825 dairy cows from a commercial dairy farm in central California were used to evaluate effects of one or 2 doses of an injectable trace mineral supplement containing 20 mg/mL of zinc, 20 mg/mL of manganese, 5 mg/mL of selenium, and 10 mg/mL of copper on first-service conception rate. Cows were randomly allocated into treatment or control group to either a single dose (experiment 1) or a double dose (experiment 2) of injected supplement. Allocation was based on days in lactation for experiment 1 and the length of gestation periods for experiment 2. In experiment 1, cows 38 to 45 d in lactation (n = 190) received a single dose of 5 mL of injected supplement. Similar cows were used as controls (n = 227). In experiment 2, cows and pregnant heifers received an initial injection of 5 mL of the mineral supplement from 2 to 3 wk precalving (n = 186). An equal dose was repeated 38 to 45 d in lactation. A similar group of cows and pregnant heifers served as controls for experiment 2 (n = 222). Health and reproductive events postcalving were recorded. In experiment 1, the odds of first-service conception were not significantly different for cows receiving a one-dose regimen of minerals compared with untreated control cows; conception rates were 26.8 and 27.5% for experiment 1 treatment and control groups, respectively. In experiment 1, the odds of first-service conception were significantly lower (odds ratio = 0.66) for cows and heifers given the 2-dose regimen of minerals compared with untreated controls; overall conception rates were 21.5 and 31.5% for experiment 2 treatment and control groups, respectively. In this intensively managed dairy herd, a single dose of injected trace minerals before breeding had no beneficial effects on first-service conception rate. However, dairy cows receiving a dose of trace minerals before calving and another dose before breeding had lower conception at first service.

Animals↗

PubMed1984

A double-blind randomized evaluation of converting enzyme inhibition as the first-step treatment of mild to moderate hypertension.

The new angiotensin converting enzyme inhibitor, enalapril (MK-421), was tested by a double-blind trial. Patients with uncomplicated essential hypertension were randomly allocated to one of two stepped-care treatment groups: enalapril 20 mg once-a-day, or placebo as the first step, followed when necessary by the successive addition of hydrochlorothiazide (25 and 50 mg), oxprenolol (160 and 320 mg) and dihydralazine (50 and 100 mg). Blood pressure was normalized in both groups, although the enalapril group showed lower systolic and diastolic blood pressures than the placebo group (systolic 130.5 +/- 12 versus 136.6 +/- 9 mmHg, P less than 0.01; diastolic 82.8 +/- 6 versus 87.0 +/- 5 mmHg, P less than 0.001). These results were obtained with a smaller number of tablets per day (2.6 +/- 1.8 versus 4.2 +/- 2.4 mmHg, P less than 0.0001). Plasma potassium was identical for both groups at the start of treatment. At the end of the study, it was significantly higher in the enalapril group than in the placebo group (4.1 +/- 0.3 versus 3.9 +/- 0.5 mmol/l; P less than 0.05). Spontaneous complaints were noted during the bi-weekly or monthly visit and were also expressed by patients completing a self-administered questionnaire. Differences in spontaneous complaints or in the symptoms evaluated by the questionnaire were not significant. The increase in the number of symptoms at the end of the study was greater in the placebo group than in the enalapril group, but the difference was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1984

Ranitidine and metoclopramide for prophylaxis of aspiration pneumonitis in elective surgery.

The effects of preanesthetic oral ranitidine and metoclopramide on gastric contents were studied in 150 inpatients scheduled for elective surgery with random allocation into ten groups with fifteen patients in each group. Patients in group I served as controls. Group II patients received metoclopramide, 10 mg, in the morning. Patients in group III received ranitidine, 150 mg; while group IV patients received ranitidine, 150 mg, and metoclopramide, 10 mg, also in the morning. Group V patients received ranitidine, 150 mg, at bedtime and in the morning; while patients in group VI received ranitidine as in group V and, in addition, received metoclopramide, 10 mg, in the morning. Group VII patients received ranitidine, 300 mg, in the morning; while patients in group VIII received ranitidine, 300 mg, and metoclopramide, 10 mg, in the morning. Patients in group IX received ranitidine, 300 mg, at bedtime and in the morning; while group X patients received ranitidine as in group IX, and in addition, received metoclopramide, 10 mg, in the morning. Patients with gastric pH less than or equal to 2.5 or gastric content volume greater than or equal to 20 ml were defined to be at risk of pulmonary damage in the event of aspiration. Patients in group I had a mean gastric pH of 2.33 with 73% of the patients with pH less than or equal to 2.5, while 47% of the patients presented with a combination of pH less than or equal to 2.5 and volume greater than or equal to 20 ml. Ranitidine and metoclopramide independently and in combination significantly reduced risk factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1996

Pressure-limited ventilation with permissive hypercapnia and minimum PEEP in saline-lavaged rabbits allows progressive improvement in oxygenation, but does not avoid ventilator-induced lung injury.

OBJECTIVE: To determine whether pressure-limited intermittent mandatory ventilation with permissive hypercapnia and positive end-expiratory pressure (PEEP) titrated to arterial oxygen tension (PaO2) prevents or reduces acute lung injury, compared to conventional ventilation, in saline-lavaged rabbits. DESIGN: Prospective randomised trial. SETTING: University animal laboratory. SUBJECTS: 18 New Zealand White rabbits. INTERVENTIONS: Following five sequential saline lung lavages, anaesthetised rabbits were randomly allocated in pairs to receive either of two ventilation protocols using intermittent mandatory ventilation. The study group had peak inspiratory pressure limited to 15 cm H2O and arterial partial pressure of carbon dioxide (PaCO2) was allowed to rise. The control group received 12 ml/kg tidal volume with rate adjusted for normocarbia. PEEP and fractional inspired oxygen (FIO2) were adjusted to maintain, PaO2 between 8 and 13.3 kPa (60 and 100 mm Hg) using a predetermined protocol. At 10 h or following death, lung lavage was repeated and lung histology evaluated. MEASUREMENTS AND MAIN RESULTS: The mean increase in lavage cell counts and protein concentration and hyaline membrane scores were not significantly different between the groups. Oxygenation progressively improved more in the study group (p = 0.01 vs control for PaO2/FIO2 ratio and alveolar-arterial oxygen tension gradient (AaDO2)). PEEP was similar and the mean airway pressure higher in the control group, suggesting that this probably resulted from less ventilator-induced injury in the study group. Four deaths occurred in the control group (three due to pneumothorax and one to hypoxaemia) and none in the study group (p = 0.08). CONCLUSIONS: This ventilatory protocol may have failed to prevent lung overdistension or it may have provided insufficient PEEP to prevent injury in this model; PEEP greater than the lower inflection point of the pressure-volume curve has been shown to prevent injury almost entirely.

Animals↗

PubMed1994

Successful embryo transfer following artificial insemination of superovulated fallow deer (Dama dama).

Thirty-four European fallow deer (Dama dama dama) were randomly allocated into embryo donor (n = 12) or embryo recipient (n = 22) groups. All does were treated with controlled internal drug release (CIDR) devices for 14 days. Animals in the embryo donor group were further treated with 200 I.U. pregnant mare serum gonadotrophin (PMSG) and 0.5 units ovine follicle-stimulating hormone (FSH). PMSG was administered 72 h before withdrawal of CIDR devices and FSH was given in eight 0.063 unit injections at 12-hourly intervals starting at the time of PMSG administration. All embryo donor animals were inseminated, by laparoscopy in both uterine horns, 36 h after withdrawal of CIDR devices with 25 x 10(6) fresh spermatozoa collected from Mesopotamian fallow deer (Dama dama mesopotamica). Embryos were recovered by laparotomy on Day 3 (n = 6) or Day 6 (n = 6) after withdrawal of CIDR devices and the ovarian response was determined. In total, 22 embryos were transferred into the oviduct (2-4-cell stage, n = 14) or uterine horn (morula stage, n = 8) on Day 3 or Day 6 after withdrawal of CIDR devices respectively. The overall means (+/- s.e.m.) of total follicular response and corpora lutea were 24.2 +/- 3.5 and 14.1 +/- 3.6 respectively. The mean number of large unruptured follicles was higher on Day 6 than on Day 3 (13.5 +/- 2.9 v. 6.7 +/- 1.3, P < 0.05). The overall embryo recovery rate was 45.8%. There was no difference in pregnancy rate following transfer of embryos on either Day 3 or Day 6 (7/14 v. 5/8 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2005

The effects of botulinum-A toxin on bladder function and histology in spinal cord injured rats: is there any difference between early and late application?

PURPOSE: We explored the effects of early and late application of botulinum-A toxin (BTX-A) on reservoir function and histological bladder changes in spinal cord injured rats. MATERIALS AND METHODS: The study was done in 30 Sprague-Dawley rats randomly allocated into 5 groups. Group 1 of 6 rats underwent sham operation only. Group 2 of 6 rats underwent spinal cord transection. Group 3 of 6 rats underwent spinal cord transection followed by BTX-A application into the detrusor muscle 7 days later. Group 4 of 6 rats underwent spinal cord transection, followed by BTX-A application into the detrusor muscle 28 days later. Group 5 of 6 rats underwent spinal cord transection followed by saline injection into the detrusor muscle after 28 days. Spinal cord injury was created by transecting the cord at the T9 to T10 level. All rats underwent cystometric examination initially and on day 42 before sacrifice. The bladders were removed and examined histologically for fibrosis and hyperplasia. RESULTS: On cystometric examination BTX-A caused an improvement in baseline pressure, and the frequency and amplitude of uninhibited detrusor contractions (p <0.001). No significant differences were observed in maximal bladder capacity or urethral opening pressure (p >0.05). Histologically BTX-A led to decreased fibrosis and hyperplasia (p <0.001). No significant differences were found between histological or cystometric among the groups with respect to receiving BTX-A in the early and late periods (p >0.05). CONCLUSIONS: BTX-A has a functional and histological healing effect on detrusor hyperreflexia subsequent to spinal cord injury in rats. Although administering BTX-A in the early period had better quantifiable functional and histological outcomes compared to the late period, the difference was not statistically significant.

Animals↗

PubMed1997

Effects of vitamin E and selenium on some rumen parameters in lambs.

The effects of supplemented selenium and vitamin E on a number of rumen parameters such as the population of rumen protozoa, pH, concentration of volatile fatty acids and ammonia nitrogen in the rumen content were studied. Eight lambs were randomly allocated into two groups: a control group and an experimental group receiving vitamin E (DL-alpha-tocopheryl acetate, 250 mg/kg of feed) and selenium (sodium selenite, 0.3 mg/kg of feed) supplementation. Samples of rumen content were taken from all lambs three times daily once a week (before feeding as well as 3 and 6 h after feeding) over a period of 10 consecutive weeks. In addition, the lambs were weighed at the end of experiment. The total counts and percentage proportions of rumen protozoa, the pH value, and the levels of ammonia nitrogen and volatile fatty acids were determined in the samples of rumen content. The levels of acetic acid, propionic acid, butyric acid and total volatile fatty acids, the total counts of protozoa, and the percentage proportion of Diplodinium were found to be significantly higher in the supplemented than in the control group (P < 0.05, P < 0.01), whereas the pH values and the percentage proportion of Dasytricha ruminantium were significantly lower in the supplemented group than in the control (P < 0.05). However, there was no statistically significant difference between the two groups in ammonia nitrogen levels. The body mass gain of lambs in the supplemented group was significantly higher than that of the control animals (P < 0.01). Combined selenium and vitamin E supplementation of the lambs' ration caused an increase in the levels of volatile fatty acids, total counts of protozoa, and body mass gain while decreasing the pH value of the rumen content.

Acetic Acid↗

PubMed1998

The effect of gonadotrophin releasing hormone and follicle stimulating hormone in conjunction with pregnant mare serum gonadotrophin on the superovulatory response in crossbred sheep in India.

Thirty-two mature crossbred (Fine Wool Synthetic, FWS) sheep developed for fine wool production in India were treated for superovulation and oestrus synchronization in spring season. The ewes were randomly allocated to four treatment groups in a factorially designed experiment. For induction of superovulation, pregnant mare serum gonadotrophin (PMSG) was administered alone (group 1), in combination with gonadotrophin releasing hormone (GnRH) (group 2) or with follicle stimulating hormone (FSH) (group 3) and with both (group 4). Oestrus was synchronized in all the ewes by two injections of prostaglandin F2 alpha (PGF, 10 mg each) administered at an interval of 10 days. Superovulation treatment started 48 h prior to the second PGF injection. The proportion of ewes in oestrus did not differ significantly (p > 0.05) in the four groups. The use of GnRH set the ewes into oestrus earlier than the ewes in the other groups. Treatment with PMSG (800 IU) in conjunction with 4 micrograms of Buserilin (GnRH) increased the ovulation rate (9.1 +/- 2.6 corpora lutea (CL)) above that observed when PMSG was used alone (3.0 +/- 0.7 CL). The use of FSH (0.5 U ovagen) in conjunction with PMSG was characterized by a decrease in the proportion of ewes with < or = 2 CL (4/8 vs 7/8; p < 0.05) and in the number of ovulations, i.e. CL observed (2.4 +/- 0.6 vs 9.1 +/- 2.6), and a nonsignificant increase in the incidence of large follicles (LF) (4.6 +/- 1.28 vs 3.25 +/- 0.6; p > 0.05). The interaction between treatments of FSH and GnRH was not significant (p > 0.05). It is concluded that use of GnRH, in conjunction with either PMSG alone or PMSG plus FSH treatment, advanced the onset of oestrus and increased the ovulation rate in FWS sheep.

Animals↗

PubMed2000

Wound modulation after trabeculectomy by different formulations of antimetabolites in rabbits.

A prospective, randomized study was performed to examine the effects of subconjunctival retention of 5-fluorouracil (5-FU) microparticles or 5-FU microparticles combined with mitomycin-C (MMC) on the success of trabeculectomy procedure in 32 New Zealand white rabbits. Drug-loaded microparticles were prepared using a biodegradable polymer, 50:50 ploy (D,L-lactide-co-glycolide) (50:50, PLG, MW 9000), by an oil-in-oil emulsification/solvent extraction technique. Each rabbit underwent trabeculectomy on both eyes, then one of the 5-FU and/or MMC preparations was placed at the site of the filtering surgery intraoperatively in the right eye, while the left eye was used as a control. The rabbits were randomly allocated to one of four treatment groups: group 1 rabbits received 5% 5-FU microparticles 10 mg; group 2 rabbits received 10% 5-FU microparticles 10 mg; group 3 rabbits received 10% 5-FU microparticles 5 mg and MMC 0.01 mg (5-FU/MMC); and group 4 rabbits received MMC 0.02 mg. Postoperatively, intraocularpressure (IOP), bleb survival, complications and IOP dynamics were compared during a follow-up period of 42 days. The results showed that IOPs were significantly lower in the eyes that received groups 3 and 4 treatments, while the eyes that received low concentrations of 5-FU microparticles resulted in no difference in IOPs as compared with those of controls. At 42 days, blebs were present in 100% of the eyes treated with 5-FU/MMC and MMC, but 0% of the eyes treated with 5-FU microparticles. The blebs in the eyes treated with MMC 0.02 mg were thinner, and significant complications (endophthalmitis, transient corneal opacification and neovascularization) occurred. In addition, the IOP dynamics study revealed that the eyes treated with 5-FU/MMC and MMC resulted in less IOP spikings after intravenous infusion of 0.9% NaCl solution. Our study suggested that the use of 5-FU microparticles in promoting the success of trabeculectomy in rabbits is dose-dependent, and its effect is less potent than a single intraoperative application of MMC.

Animals↗

PubMed1995

The combined effects of dietary fat and estrogen on survival, 7,12-dimethylbenz(a)anthracene-induced breast cancer and prolactin metabolism in rats.

The relationships between dietary fat concentration (10 or 40% of energy), fat source (corn oil or beef tallow) and estrogen (control, ovariectomy or ovariectomy with estrogen replacement) to 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast carcinogenesis and survival in rats were studied in a 2 x 2 x 3 factorial experiment. Female Sprague-Dawley rats given DMBA (2.5 mg/100 g body wt, intragastric) at 55 d of age were randomly allocated to three groups 48 h later: sham ovariectomy (control), ovariectomy (OVX) or ovariectomy with a subcutaneous estrogen implant (OVX+E). Each group was subdivided into dietary groups fed 10 and 40% of energy as corn oil or beef tallow for 70 wk. OVX+E rats exhibited serum estrogen concentrations in excess of physiologic values. Survival at 70 wk for the 3 hormonal groups was control 51%, OVX 67% and OVX+E 13%. Mortality in controls was doubled by feeding a high fat diet; no diet effect was detected in OVX or OVX+E rats. Palpable tumors developed in 74, 14 and 60% of control, OVX and OVX+E rats, respectively. High fat diets approximately doubled the hazard of developing a palpable tumor. Adenocarcinoma prevalence was 58, 12 and 63% in control, OVX and OVX+E rats, respectively. The odds of having any tumor, an adenocarcinoma or an adenoma were multiplied by 3.6, 2.8 and 2.3, respectively, for rats fed high vs. low fat. Additional studies showed that diet had no effect on serum prolactin or estrogen concentrations or metabolism and clearance of intravenously administered radiolabeled prolactin. We demonstrated that high dietary fat concentration enhances breast carcinogenesis independently of cyclic ovarian function, although the presence of estrogen may be a prerequisite for significant dietary modulation. The effect of fat on breast cancer is not mediated by major changes in systemic prolactin metabolism.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1990

Influence of vitamin D3, 1 alpha-hydroxyvitamin D3, and 1,25-dihydroxyvitamin D3 on eggshell quality, tibia strength, and various production parameters in commercial laying hens.

Four hundred 53-wk-old Hyline W36 laying hens were randomly allocated to 10 treatments. The effects of feeding two vitamin D3 metabolites, 1 alpha-hydroxyvitamin D3 [1 alpha-(OH) D3] and 1,25-dihydroxyvitamin D3 [1,25-(OH)2 D3], each at five dietary levels (0, .75, 1.50, 3.00, and 4.50 micrograms/kg of feed) were determined on eggshell quality and tibia strength in commercial laying hens (Experiment 1). In Experiment 2, 1,440 Hyline W36 65-wk-old laying hens were used to determine the effects of four levels of vitamin D3 (0, 500, 1,000, and 1,500 ICU vitamin D3/kg) and three levels of dietary 1,25-(OH)2 D3 (0, .5, and 1.0 microgram/kg of feed) on eggshell quality, tibia strength, and egg production. In Experiment 1, neither 1,25-(OH)2 D3 nor 1 alpha-(OH) D3 affected eggshell quality or production criteria. Tibia weight was increased by adding either 1,25-(OH)2 D3 or 1 alpha-(OH) D3. In Experiment 2, 1,25-(OH)2 D3 increased percentage of shell, shell weight, and egg breaking strength when 0 ICU D3/kg was fed but had no effect at higher levels of vitamin D3. Egg production, feed consumption, and egg weight were also increased with supplemental 1,25-(OH)2 D3 when 0 ICU D3/kg was fed. Tibia weight and tibia breaking strength were also increased by adding 1,25-(OH)2 D3 to the diet. The commercial laying hen metabolizes sufficient 1,25-(OH)2 D3 from dietary vitamin D3 to maintain shell quality but not enough to maintain tibia strength.

Animals↗

PubMed2006

Open lung ventilation preserves the response to delayed surfactant treatment in surfactant-deficient newborn piglets.

OBJECTIVE: Delayed surfactant treatment (>2 hrs after birth) is less effective than early treatment in conventionally ventilated preterm infants with respiratory distress syndrome. The objective of this study was to evaluate if this time-dependent efficacy of surfactant treatment is also present during open lung ventilation. DESIGN: Prospective, randomized controlled animal study. SETTING: University-affiliated research laboratory. SUBJECTS: Thirty-eight newborn piglets. INTERVENTIONS: Following repeated whole-lung lavage, animals were randomly allocated to conventional positive pressure ventilation (PPVCON) using a positive end-expiratory pressure (PEEP) of 5 cm H2O and a tidal volume of 7 mL/kg or open lung positive pressure ventilation (PPVOLV). During PPVOLV, collapsed alveoli were actively recruited and thereafter stabilized with sufficient PEEP. Within each ventilation group, animals received surfactant (25 mg/kg) either after 2 hrs (PPVCON-2 and PPVOLV-2) or after 4 hrs (PPVCON-4 and PPVOLV-4) of ventilation. A control group received surfactant immediately after lung lavage. Following surfactant administration, all animals were conventionally ventilated for an additional 2 hrs. MEASUREMENTS AND MAIN RESULTS: Two hours after surfactant treatment, both oxygenation and lung mechanics showed a clear deterioration in the PPVCON-4 group compared with PPVCON-2 and the control group. However, this deterioration of the surfactant response over time was not observed during PPVOLV. Analysis of the bronchoalveolar lavage fluid obtained at the end of the experiment showed that the protein concentration and the conversion of large to small aggregate surfactant was significantly higher in the PPVCON-4 group compared with the PPVCON-2 group while comparable in both PPVOLV groups. In addition, interleukin-8 and myeloperoxidase levels tended to be higher in the PPVCON-4 group compared with the PPVOLV-4 group. CONCLUSIONS: In contrast to conventional ventilation, open lung ventilation preserves the response to delayed surfactant treatment in surfactant-deficient newborn piglets. This sustained response is accompanied by an attenuation of secondary lung injury.

Animals↗

PubMed1992

Clinical and histologic evaluation of the prolapsed third eyelid gland in dogs.

Eighteen prolapses of the gland of the third eyelid in 17 Beagles were randomly allocated to 3 groups, which included nontreated (group 1, n = 6), excised (group 2, n = 4), and surgically repositioned (group 3, n = 8) glands. A schirmer tear test (STT) was performed on affected and normal (control) eyes for 5 consecutive days on weeks 0 (baseline), 2, 4, 6, 8, 10, 12, 16, 18, 20, and 24. All prolapsed third eyelid glands were excised and examined histologically. Ten female and 7 male Beagles were used in the prospective study. Mean age at prolapse was 35.1 weeks (range, 6 to 89 weeks). Control STT data revealed a population mean of 22.2 +/- 2.1 mm/min. Complications developed in 4 of 6 eyes when the gland was allowed to remain in a prolapsed position. Complications for group-1 eyes were significantly (P < 0.005) greater than those for eyes in groups 2 and 3 (0 of 12). Comparison of affected and control eye baseline data revealed decreased STT values for eyes with prolapsed glands (P < 0.01). Mean differences between affected and control eyes were 2.2, 2.0, and 3.4 mm/min for groups 1, 2, and 3, respectively. A significant (P < 0.001) decrease in lacrimation (0.2 to 3.1 mm/min) in group-2 eyes was detected after removal of the gland. Tear production for affected eyes of nontreated dogs fluctuated above and below that of control eyes prior to excision of the prolapsed gland of the third eyelid; however, with time, affected and control eye STT values were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1999

Effects of laparotomy, and carbon dioxide and air pneumoperitoneum, on cellular immunity and peritoneal host defences in rats.

OBJECTIVE: To assess the effects of laparotomy, and insufflation of carbon dioxide and air, on the immune system in rats. DESIGN: Randomised laboratory study. SETTING: Teaching hospital, Turkey. ANIMALS: 77 Wistar rats randomly allocated to 2 groups one of which was sensitised with dinitrofluorobenzene (DNFB, n = 43) and one of which was not (n = 34). INTERVENTIONS: The DNFB group was sensitised and subdivided into control (n = 8), laparotomy alone (n = 7), and insufflation with carbon dioxide (CO2) for 30 and 60 mins (n = 7 in each) or room air for 30 and 60 mins (n = 7 in each). A week later DNFB was reapplied to the ears. In the group not sensitised with DNFB the animals were subdivided similarly, the corresponding numbers in each group being, 6, 6, 6, 6, 5, and 5. MAIN OUTCOME MEASURES: Delayed type hypersensitivity (DTH) measured by ear swelling in the DNFB group, and peritoneal bactericidal activity, total free peritoneal cell counts (TPC), and cell types in the non-sensitised group. RESULTS: There were significant differences in the degree of ear swelling in the DNFB group between control and laparotomy groups (p = 0.0001) and between control and both insufflations of air (p = 0.002 and p = 0.0003, respectively). In the non-sensitised group peritoneal bactericidal activity was significantly increased after 7 hours in the 60 mins air insufflation group (p = 0.04). At 24 hours there were no differences among the groups. TPC were not affected. The number of peritoneal polymorphonuclear leucocytes (PMN) was significantly higher in the laparotomy alone group than in the control or any of the insufflation groups (p < 0.05). CONCLUSIONS: Laparotomy and air insufflation depressed cell-mediated immunity. Peritoneal bactericidal activity was affected only after 60 minutes of air insufflation.

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