Correlation between fetoplacental Doppler indices and measurements of cardiac function in term fetuses.

OBJECTIVE: Redistribution of cardiac output (CO) is responsible for the brain-sparing effect seen during periods of fetal stress. Our aim was to investigate prospectively the correlation between fetoplacental Doppler indices and measurements of cardiac function in uncomplicated term singleton pregnancy. METHODS: This was a prospective observational study of normotensive women with appropriately grown, non-anomalous singleton pregnancy. Participants underwent fortnightly ultrasound examinations from 36 weeks' gestation until delivery, and intrapartum and neonatal outcomes were recorded. The correlation between fetoplacental Doppler indices and various measurements of cardiac function was evaluated. RESULTS: The study cohort comprised 273 singleton pregnancies. The cerebroplacental ratio (CPR) was correlated positively with left ventricular CO (LVCO) (P < 0.001, rho = 0.29), left-to-right ventricular CO ratio (LVCO/RVCO; P < 0.001, rho = 0.41), global left ventricular strain (P < 0.01, rho = 0.17) and global right ventricular strain (P < 0.001, rho = 0.22). The CPR was correlated inversely with the left ventricular myocardial performance index (P < 0.01, rho = -0.18) and the RVCO (P < 0.001, rho = -0.28). The LVCO and global left ventricular strain were correlated positively with umbilical venous flow (P = 0.04, rho = 0.18 and P < 0.001, rho = 0.25, respectively). There was minimal or no correlation between either the mean uterine artery pulsatility index (PI) or umbilical artery PI with any cardiac indices. CONCLUSION: The fetal CPR, middle cerebral artery PI and umbilical venous flow are correlated positively with LVCO, LVCO/RVCO and global left ventricular strain in low-risk term pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Prelabor screening for intrapartum fetal compromise in low-risk pregnancies at term: cerebroplacental ratio and placental growth factor.

OBJECTIVES: To determine the screening performance of low fetal cerebroplacental ratio (CPR), a marker of fetal adaptation to suboptimal growth, and maternal placental growth factor (PlGF) level, both in isolation and in combination, for the prediction of Cesarean section (CS) for intrapartum fetal compromise (IFC) and composite adverse neonatal outcome (CANO). METHODS: This was a prospective cohort study in low-risk women with uncomplicated singleton pregnancy from 36 weeks' gestation to delivery. CPR and PlGF were assessed fortnightly and intrapartum and neonatal outcomes were recorded. CPR and PlGF values from the final assessment for each woman were corrected for gestational age and assessed for screening performance, firstly as continuous variables and then as binary predictors. RESULTS: Of the 264 women who consented to participate in the study, 207 were included in the final analysis. Seven pregnancies required CS for IFC and 38 had CANO. Pregnancies delivered by CS for IFC had lower CPR and PlGF centiles than those in all other pregnancies. Pregnancies with CANO had a lower PlGF centile. The greatest areas under the receiver-operating characteristics curves (AUCs) for the prediction of CS for IFC (0.92; 95% CI, 0.86-0.97) and CANO (0.64; 95% CI, 0.54-0.74) were achieved by a combination of CPR 20th and PlGF 33rd centile thresholds. This produced sensitivities, specificities and positive likelihood ratios for the prediction of CS for IFC of 100%, 86% and 7.14, respectively, and 34.2%, 87.0% and 2.63, respectively, for the prediction of CANO. There was no statistical difference in the AUC for CS for IFC between the combined model and when CPR was used alone, or for CANO between the combined model and CPR or PlGF in isolation. CONCLUSIONS: This pilot proof-of-concept study describes the screening performance of CPR and maternal PlGF level for CS for IFC in low-risk women from 36 weeks' gestation. It was found that CPR and maternal PlGF improved the overall predictive utility for CS for IFC, as well as that for CANO. However, given the lack of significant difference between the combined model and its individual components, it is debatable whether the combined model is a superior screening test. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Relationship of prelabor fetal cardiac function with intrapartum fetal compromise and neonatal status at term.

OBJECTIVES: To investigate prospectively the relationship of fetal cardiac function and Doppler ultrasound parameters with intrapartum fetal compromise (IFC) in appropriately grown term fetuses. Secondary aims were to correlate prenatal cardiac function with neonatal acid-base status, intrapartum fetal heart rate (FHR) abnormalities and adverse neonatal outcomes. METHODS: This was a blinded, prospective, observational, cohort study of 270 women with an uncomplicated singleton pregnancy who underwent fortnightly ultrasound assessment from 36 weeks' gestation until delivery at the Mater Mother's Hospital, Brisbane, Australia. Fetal cardiac output and blood flow parameters were assessed and correlated with intrapartum and neonatal outcomes. The primary outcome was need for operative (either Cesarean or instrumental vaginal) delivery for IFC. Secondary outcome measures were acidosis at birth, 5-min Apgar score ≤ 7, suspicious or pathological FHR abnormalities and admission to the neonatal intensive care unit. RESULTS: Two hundred and seventy women were included in the analysis, of whom 51 (18.9%) had an emergency operative delivery for IFC. Fetuses that had emergency delivery for IFC showed lower mean left ventricular cardiac output (LVCO) (560 ± 44 mL/min vs 617 ± 73 mL/min; P < 0.001), lower mean LVCO/right ventricular cardiac output (RVCO) ratio (0.55 ± 0.07 vs 0.64 ± 0.11; P < 0.001), lower mean cerebroplacental ratio (CPR) (1.62 ± 0.3 vs 1.90 ± 0.5; P < 0.001) and higher mean RVCO (1026 ± 105 mL/min vs 978 ± 110 mL/min; P = 0.003) compared with those that did not develop IFC. Additionally, LVCO and CPR were lower in fetuses with adverse neonatal outcome. CONCLUSION: Term fetuses with estimated fetal weight > 10th centile that develop IFC have evidence of lower LVCO and higher RVCO, which are in turn associated with poorer condition of the newborn. Fetal CPR is positively correlated with LVCO. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Cerebroplacental ratio thresholds measured within 2 weeks before birth and risk of Cesarean section for intrapartum fetal compromise and adverse neonatal outcome.

OBJECTIVES: Prediction of intrapartum fetal compromise in uncomplicated, term pregnancies is a global obstetric challenge. Currently, no widely accepted screening test for this condition exists, although the cerebroplacental ratio (CPR) shows promise. We aimed to evaluate prospectively the screening performance of the CPR 10th centile threshold for prediction of Cesarean section for intrapartum fetal compromise (IFC) and composite adverse neonatal outcome (ANO) after 36 weeks' gestation in low-risk women, and to compare this with CPR ≤ 1 and < 5th centile thresholds described previously in the literature. METHODS: This was a blinded, prospective, observational, cohort study of 483 women with uncomplicated singleton pregnancy who underwent fortnightly CPR measurements from 36 weeks to delivery, and their intrapartum and neonatal outcomes were recorded. The CPR 10th centile threshold screening performance was calculated for emergency Cesarean section for IFC and composite ANO (defined as acidosis at birth, 5-min Apgar score < 7 and/or admission to the neonatal intensive care unit). Comparison of screening performance of CPR ≤ 1 and < 5th and < 10th centile thresholds was also undertaken for these specified outcomes. RESULTS: In total, 437 women were included in the analysis, of whom 4.1% had an emergency Cesarean section for IFC and 17.8% had a composite ANO. Sensitivity and specificity for CPR < 10th centile were, respectively, 55.6% and 87.9% for prediction of Cesarean section for IFC, and 28.2% and 88.0% for composite ANO. Compared with CPR ≤ 1 and < 5th centile, CPR < 10th centile yielded the best overall test performance for detection of Cesarean section for IFC and composite ANO, although its predictive value was only fair for Cesarean section for IFC (area under the receiver-operating characteristics curve (AUC) = 0.72) and poor for composite ANO (AUC = 0.58). CONCLUSION: The CPR 10th centile threshold may be useful as a component of a risk assessment tool for Cesarean section for IFC in low-risk pregnancies at term. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Myocardial strain assessment using velocity vector imaging in normally grown fetuses at term.

OBJECTIVES: To assess prospectively fetal myocardial deformation at term in normally grown fetuses using the velocity vector imaging (VVI) two-dimensional speckle-tracking technique, and to explore myocardial deformation changes over the last 4 weeks of pregnancy. METHODS: This was a prospective, observational cohort study of 276 women with an uncomplicated singleton pregnancy who underwent fortnightly ultrasound from 36 weeks' gestation until delivery at the Mater Mother's Hospital, Brisbane, Australia. Fetal myocardial deformation (assessed by global and segmental longitudinal systolic myocardial strain and strain rate of both right and left ventricles) was measured using VVI software. RESULTS: Mean global longitudinal left and right ventricular strain and strain rate values decreased between each time point. At 36, 38 and 40 weeks' gestation, left ventricular global strain (%) and strain rate (/s) decreased, respectively, as follows: -14.6 ± 3.8% and -1.2 ± 0.3/s at 36 weeks; -13.6 ± 3.3% and -1.1 ± 0.3/s at 38 weeks; and -12.3 ± 3.1% and -1.0 ± 0.3/s at 40 weeks. At 36, 38 and 40 weeks, mean right ventricular global strain (%) and mean strain rate (/s) decreased, respectively, as follows: -14.2 ± 3.4% and -1.2 ± 0.2/s at 36 weeks; -13.4 ± 3.0% and -1.1 ± 0.2/s at 38 weeks; and -12.8 ± 2.8% and -1.1 ± 0.2/s at 40 weeks. CONCLUSIONS: Global ventricular strain values diminish with advancing gestational age. Myocardial deformation imaging is feasible in late gestation and may be useful as an adjunct for the assessment of fetal cardiac function close to birth. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Magnitude of change in fetal cerebroplacental ratio in third trimester and risk of adverse pregnancy outcome.

OBJECTIVES: To evaluate whether the magnitude of change in the cerebroplacental ratio (CPR) after 30 weeks' gestation is a better predictor of adverse pregnancy outcome compared with a single CPR measurement at 35-37 weeks. A secondary aim was to evaluate whether the utility of CPR at 35-37 weeks was enhanced after adjusting for change in gestational age. METHODS: This was a retrospective cohort study of women who had at least two ultrasound scans between 30 and 37 weeks' gestation, with the final scan at 35-37 weeks. Exclusion criteria were major congenital abnormality, aneuploidy, multiple pregnancy and unknown middle cerebral artery pulsatility index or umbilical artery pulsatility index. A normal reference range for CPR was derived from a separate cohort of women with normal outcome and a Generalised Additive Model for Location, Scale and Shape was fitted to derive standardized centiles. These reference centiles were then used to calculate Z-scores for the study cohort. Logistic regression models and receiver-operating characteristics (ROC) curves were used to evaluate the predictive utility of CPR Z-score at last CPR measurement and the change in CPR on mode of delivery, neonatal outcome and composite neonatal outcome. The area under the ROC curve (AUC) for each model was compared before and after adjustment for parity, hypertension, diabetes, body mass index and smoking status. RESULTS: A total of 1860 women met the inclusion criteria. There was no association between the magnitude of change in CPR and composite adverse pregnancy outcome (P = 0.92). Of the outcomes that made up the composite, an increase in CPR Z-score over time was associated with a lower risk for emergency Cesarean delivery (P < 0.001) and emergency Cesarean delivery for non-reassuring fetal status (P = 0.02). It was also associated with a lower risk of birth weight < 10th centile (P = 0.01) and hypoglycemia (P = 0.001). There was no significant difference between the AUCs of last CPR Z-score and last CPR Z-score adjusted for the change in gestational age in predicting pregnancies at risk for adverse outcome. CONCLUSIONS: Our results suggest that both the individual CPR Z-score and the magnitude and direction of change in CPR Z-score can identify pregnancies at risk of various adverse perinatal outcomes. However, the CPR Z-score at 35-37 weeks' gestation appears to be a better predictor. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

A survey on the use of rugs in Australian horses.

The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and competition were significantly associated with the use of rugs. Nearly all respondents (89.0%) felt that 'over-rugging' was a concern. However, 4.8% of owners would use up to 4 rugs at any one time on their horse and 21.4% of horses were still rugged in temperatures above 20°C in Australia. Many Australian horse owners (42.8%) also believe that horses feel cold if they are not rugged. Anthropomorphism when it comes to rugging horses cannot be justified as the horse has a much wider thermoneutral zone (TNZ) than humans. Australian climate, owner opinions, equestrian discipline and whether a horse is used for riding influence Australian horse rugging practices. However, current practices are based on limited available research and are not necessarily to the benefit of the horse. The major limitation was that the survey likely attracted respondents who are interested in the topic creating a self-selection bias.

Comparative pharmacokinetics and pharmacodynamics of tablet, suspension and paste formulations of atenolol in cats.

This study compared the pharmacokinetic and pharmacodynamic profiles of an extemporaneously prepared (compounded) atenolol paste and suspension for oral administration, against the commercially available divided tablet in healthy cats. Eleven healthy cats (mean: age 4 ± 0.4 year, weight 5.0 ± 0.7 kg) were dosed twice-daily with 12.5 mg atenolol (tablet, paste or suspension) for 7 days in a randomized cross-over design with a 7-day wash-out period. On day 7, an electrocardiogram was performed before and immediately after stress provocation (jugular venipuncture) at prestudy screening, and at 2, 6 and 12 h after morning dosing. Systolic arterial blood pressure (BP) was assessed following the second electrocardiogram. Plasma was collected at prestudy screening, and at 1, 2, 6 and 12 h to measure atenolol plasma concentrations. Mean atenolol dose was 2.5 mg/kg (range: 2.1-3.3 mg/kg). Stress-induced rise in heart rate was attenuated (P < 0.05) at every time point compared to baseline for all formulations. Although the paste significantly attenuated stress-induced elevation in heart rate at all time points, the effect was not consistently equivalent to the tablet. The BP was not altered (P > 0.05) at any time point by any formulation. In conclusion, there were no significant differences (P > 0.05) in any of the pharmacokinetic parameters or pharmacodynamic profiles of the paste and suspension compared to the commercially available tablet.

A review of 91 canine and feline red-bellied black snake (Pseudechis porphyriacus) envenomation cases and lessons for improved management.

INTRODUCTION: Most cases of red-bellied black snake (RBBS) envenomation in dogs respond favourably to treatment comprising of tiger-brown snake antivenom (TBAV), intravenous fluid therapy, analgesia and, if indicated, mechanical ventilation and/or blood transfusion. However, there remains a subset of patients who develop fatal complications despite intensive treatment and risk factors for these occurring remain unknown. Here we present a retrospective cross-sectional survey of 91 canine and feline RBBS envenomation cases. METHODS: Cases seen between June 2010 and June 2020 were retrieved from the databases of seven practices in South East and coastal Queensland. From the canine case population, logistic regression analysis was performed to assess the impact of potential risk factors at presentation on the likelihood of death. A final multivariable model was developed using a manual backwards elimination approach based on overall likelihood ratio tests and Wald chi-square P-values for each variable. Where model convergence failed due to quasi-complete separation, Firth's penalised maximum likelihood method was implemented. Such separation may occur when an outcome is completely predicted by an explanatory variable in one group. RESULTS: Of the 88 canine cases, 7 died (8.0%), all after prognosis-based euthanasia. Of the three feline cases, one died after unsuccessful resuscitation following cardiopulmonary arrest. Compared to survivors, dogs that died were older, exhibited pigmenturia, received antivenom later and had a higher total plasma protein (TPP), activated clotting time (ACT) and lower packed cell volume (PCV) at presentation.

Intra-articular methylprednisolone and bupivacaine for treatment of sesamoid disease in dogs.

INTRODUCTION: The sesamoid disease is a cause of lameness in dogs, and there is limited literature relating to diagnosis, treatment and outcome of treatment in dogs with the sesamoid disease. Our aim was to compare the efficacy of intra-articular metacarpophalangeal/metatarsophalangeal joint injection with methylprednisolone and bupivacaine (IMPB) or conservative management with nonsteroidal anti-inflammatories and rest (CMNR) for treatment of this disease. MATERIALS AND METHODS: We conducted a retrospective survey of dogs treated for the sesamoid disease with IMPB or CMNR. The medical records of all dogs that received IMPB or were recommended CMNR for treatment of sesamoid pain were reviewed, and a client questionnaire was delivered to owners. Response to treatment, rapidity of response, length of resolution and recurrence of clinical signs associated with the sesamoid disease were assessed. RESULTS: A total of 78 dogs were included in the study. One week after IMPB, 52/58 (89.7%) dogs demonstrated resolution of lameness compared with 1 week of CMNR, 0/18 (P < 0.001). There was limited statistical evidence in client satisfaction between treatment groups, IMPB 36/53 (67.9%) and CMNR 16/17 (94%) (P = 0.052). Dogs presenting with the sesamoid disease had comorbidities in 51/78 (65.4%) of cases. Elbow disease was the most common comorbidity 29/78 (37.2%). CONCLUSION: Our results support the use of IMPB for short-term (1 week) resolution of lameness associated with sesamoid disease in dogs. Dogs treated with CMNR had slower improvement; however, there was no difference in lameness or client satisfaction between treatment groups at long-term follow-up (12 months).

Dietary manipulation of Bos indicus x heifers during gestation affects the reproductive development of their heifer calves.

The effect of nutrition during the first and second trimesters of pregnancy in composite beef heifers on reproductive parameters of their female calves was determined in the present study. At artificial insemination, heifers were assigned to one of four treatment groups (i.e. HH, HL, LowH and LL) depending on the level of crude protein intake (H = high; L = low) for first and second trimesters of pregnancy. Gonadotrophin concentrations and ovarian parameters were measured in their female calves at 5 and 23 months of age. Crude protein intake was positively associated with dam plasma urea (P < 0.001). The density of healthy follicles in heifers at the time of death was negatively correlated with dam plasma urea at Day 179 (P = 0.009). Heifers from LowH dams had a smaller-sized prepubertal largest ovarian follicle (P = 0.03) and lower densities of primordial and primary follicles (P = 0.02) and healthy antral follicles (P = 0.009) when they were killed. There was a positive correlation between plasma FSH concentrations at 5 and 23 months of age (P = 0.02), as well as between the sizes of the largest ovarian follicles at 6 and 23 months of age (P = 0.01). In conclusion, the reproductive development of heifers may be affected by prenatal nutrition during early and mid-gestation.

Relationship between sources of pet acquisition and euthanasia of cats and dogs in an animal shelter: a pilot study.

OBJECTIVE: Approximately 140,000 unwanted dogs and cats are culled in Australia annually. There is a paucity of information linking sources of pet acquisition with subsequent euthanasia, which may inform evidence-based strategies to reduce euthanasia rates. This pilot study aimed to determine whether there is a higher risk of euthanasia related to the source of acquisition for pets surrendered to an animal shelter. METHODS: Data for 5391 dogs and 5581 cats surrendered to one Queensland shelter between January 2006 and December 2009 were analysed. RESULTS: The main sources of acquisition for owner-surrendered dogs were 'shelter' and 'pet shop' and for owner-surrendered cats were 'own litter' and 'shelter'. Euthanasia rates for different sources varied. For adult dogs, acquisition through newspaper advertisements was associated with the highest euthanasia rate. Adult cats obtained as gifts (from friend or family member) had the highest euthanasia rate. For junior cats, the overwhelming source was the owner's own litter (68% of intake) and only kittens acquired as strays were at significantly higher risk of euthanasia. For both dogs and cats, animals acquired from shelters had lower rates of euthanasia than most other sources, which suggests that shelter-sourced animals may be considered a preferred source for pet acquisition to assist in reducing the number of adoptable pets euthanased. CONCLUSION: There was evidence from the study animal shelter that the risk of euthanasia was related to acquisition source. These findings should be confirmed by prospective studies, which should also investigate the interaction between acquisition source and other factors, using larger data sets from a variety of shelters.

Predicting intrapartum fetal compromise using the fetal cerebro-umbilical ratio.

INTRODUCTION: The aim of this study was to explore the association between the cerebro-umbilical ratio measured at 35-37 weeks and intrapartum fetal compromise. METHODS: This retrospective cross sectional study was conducted at the Mater Mothers' Hospital in Brisbane, Australia. Maternal demographics and fetal Doppler indices at 35-37 weeks gestation for 1381 women were correlated with intrapartum and neonatal outcomes. RESULTS: Babies born by caesarean section or instrumental delivery for fetal compromise had the lowest median cerebro-umbilical ratio 1.60 (IQR 1.22-2.08) compared to all other delivery groups (vaginal delivery, emergency delivery for failure to progress, emergency caesarean section for other reasons or elective caesarean section). The percentage of infants with a cerebro-umbilical ratio <10th centile that required emergency delivery (caesarean section or instrumental delivery) for fetal compromise was 22%, whereas only 7.3% of infants with a cerebro-umbilical ratio between the 10th-90th centile and 9.6% of infants with a cerebro-umbilical ratio > 90th centile required delivery for the same indication (p < 0.001). A lower cerebro-umbilical ratio was associated with an increased risk of emergency delivery for fetal compromise, OR 2.03 (95% CI 1.41-2.92), p < 0.0001. DISCUSSION: This study suggests that a low fetal cerebro-umbilical ratio measured at 35-37 weeks is associated with a greater risk of intrapartum compromise. This is a relatively simple technique which could be used to risk stratify women in diverse healthcare settings.

An abattoir survey of equine dental abnormalities in Queensland, Australia.

OBJECTIVE: A cadaver study to estimate the prevalence of dental disorders in horses presented at an abattoir in Queensland, Australia. METHODS: Cadaver heads at a Queensland abattoir were examined for the presence of dental abnormalities and categorised into age groups. The prevalence of abnormalities was analysed by binomial observation of observed proportion, Pearson's Chi-square test or Fisher's exact correlation test. Strength of association was evaluated using Cramer's V test. RESULTS: Heads from horses (n=400) estimated to be between 1 and 30 years of age were placed into four age groups. The most common abnormalities were sharp enamel points (55.3%) and hooks (43%). The highest frequency of dental diseases and abnormalities were in horses 11-15 years old (97.5%). CONCLUSIONS: Common abnormalities were found in all groups and the prevalence increased with age. This study suggests that all horses should have regular complete dental examinations to detect and treat dental disorders in order to limit more severe dental pathologies later in life.

Evaluation and histological examination of a Campylobacter fetus subsp. venerealis small animal infection model.

Bovine genital campylobacteriosis (BGC), caused by Campylobacter fetus subsp. venerealis, is associated with production losses in cattle worldwide. This study aimed to develop a reliable BGC guinea pig model to facilitate future studies of pathogenicity, abortion mechanisms and vaccine efficacy. Seven groups of five pregnant guinea pigs (1 control per group) were inoculated with one of three strains via intra-peritoneal (IP) or intra-vaginal routes. Samples were examined using culture, PCR and histology. Abortions ranged from 0% to 100% and re-isolation of causative bacteria from sampled sites varied with strain, dose of bacteria and time to abortion. Histology indicated metritis and placentitis, suggesting that the bacteria induce inflammation, placental detachment and subsequent abortion. Variation of virulence between strains was observed and determined by culture and abortion rates. IP administration of C. fetus subsp. venerealis to pregnant guinea pigs is a promising small animal model for the investigation of BGC abortion.

Fate of swallowed interleukin 8 and TNF alpha, and effect on the Wistar rat gut.

To evaluate the passage of cytokines through the gastrointestinal tract, we investigated the digestion of interleukin-8 (IL-8) and tumour necrosis factor alpha (TNF alpha), in vitro and in vivo, and their propensity to induce intestinal inflammation. We serially immuno-assayed IL-8 and TNF alpha solutions co-incubated with each of three pancreatin preparations at pH 4.5 and pH 8. We gavaged IL-8, TNF alpha and marker into 15 Wistar rats, and measured their faecal cytokine concentrations by ELISA and histologically examined their guts. IL-8 immunoreactivity was extinguished by all pancreatin preparations after 1 h of incubation at 37 degrees C. TNF alpha concentration progressively fell from 1 to 4 h with all enzyme preparations. Buffer control samples maintained their cytokine concentrations throughout incubation. No IL-8 or TNF alpha was detected in any rat faecal pellets. There was no significant proinflammatory effect of the gavaged cytokines on rat intestine. IL-8 and TNF alpha in aqueous solution could well be fully digested in the CF gut when transit time is normal and exogenous enzymes are provided, although cytokines swallowed in viscous sputum may be protected from such digestion.

The use of air displacement plethysmography in children and adolescents with cystic fibrosis.

OBJECTIVES: The purpose of this paper was to evaluate the use of air displacement plethysmography (ADP) in children and adolescents with cystic fibrosis (CF). Specifically, the primary aim of this study was to compare estimates of fat-free mass (FFM) measured from ADP and dual energy X-ray absorptiometry (DEXA) in children and adolescents with CF. The secondary aim was to compare the effect of using predicted thoracic gas volume (VTG) and measured VTG for the calculation of FFM by ADP in this population. METHODS: Cross-sectional FFM measurements were taken using ADP and DEXA in 52 children and adolescents with CF, ranging in age from 6.3 to 16.6 y. RESULTS: Bland-Altman analysis showed that ADP values of FFM were on average 0.59 kg higher than DEXA values (95% limits of agreement = 3.61 to -2.43 kg); however this difference was not significant. There was no significant correlation (r = -0.26, P = 0.07) between the mean FFM and difference in FFM between ADP and DEXA. Using either predicted or measured VTG did not significantly affect FFM estimates in individuals with CF who had normal lung function (bias = -0.39 +/- 0.86 kg; r = -0.02, P = 0.93). CONCLUSIONS: ADP is an appropriate technique for use in children and adolescents with CF.

Energy expenditure and the body cell mass in cystic fibrosis.

Poor nutritional status in patients with cystic fibrosis (CF) is associated with severe lung disease, and possible causative factors include inadequate intake, malabsorption, and increased energy requirements. Body cell mass (which can be quantified by measurement of total body potassium) provides an ideal standard for measurements of energy expenditure. The aim of this study was to compare resting energy expenditure (REE) in patients with CF with both predicted values and age-matched healthy children and to determine whether REE was related to either nutritional status or pulmonary function. REE was measured by indirect calorimetry and body cell mass by scanning with total body potassium in 30 patients with CF (12 male, mean age = 13.07 +/- 0.55 y) and 18 healthy children (six male, mean age = 12.56 +/- 1.25 y). Nutritional status was expressed as a percentage of predicted total body potassium. Lung function was measured in the CF group by spirometry and expressed as the percentage of predicted forced expiratory volume in 1 s. Mean REE was significantly increased in the patients with CF compared with healthy children (119.3 +/- 3.1% predicted versus 103.6 +/- 5% predicted, P < 0.001) and, using multiple regression techniques, REE for total body potassium was significantly increased in patients with CF (P = 0.0001). There was no relation between REE and nutritional status or pulmonary disease status in the CF group. In conclusion, REE is increased in children and adolescents with CF but is not directly related to nutritional status or pulmonary disease.

Dietary manipulation of Bos indicusxheifers during gestation affects the prepubertal reproductive development of their bull calves.

We determined the influence of nutritional protein and energy during the first and second trimesters of pregnancy in composite beef heifers on prepubertal reproductive parameters of their male calves. At artificial insemination, heifers were stratified by weight within each composite genotype into 4 treatment groups: High/High (HH=250% crude protein (CP) and 243% metabolisable energy (ME) for first and 229% CP and 228% ME for second trimester of pregnancy), High/Low (HL=250% CP and 243% ME for first trimester and 63% CP and 176% ME for second trimester) Low/High (LowH=75% CP and 199% ME for first trimester and 229% CP and 228% ME for second trimester) or Low/Low (LL=75% CP and 199% ME for first trimester and 63% CP and 176% ME for second trimester). At 5 months of age, male calves were castrated, and gonadotrophins and testosterone (pre- and post-GnRH challenge), IGF-I and leptin were measured along with testicular parameters. Lower maternal dietary protein and energy levels during gestation were associated with increased prepubertal FSH concentrations (P=0.03) and paired testicular volume (P=0.04) in male offspring. Serum LH (P<0.001) and FSH concentrations (P=0.04) were correlated with seminiferous tubule diameter. Testosterone concentrations were positively correlated with testis measures: paired testicular weight (P<0.001), volume (P=0.03) and seminiferous tubule diameter (P<0.001). Although leptin concentrations were associated with prepubertal age (P=0.04) and body weight (P=0.006), they were not associated with any of the measures of reproductive development, but insulin-like growth factor-I was associated with prepubertal FSH (P=0.005). In conclusion, prepubertal reproductive development of bulls may be affected by prenatal nutrition during early and mid gestation.

Dystocia in 3-year-old beef heifers; relationship to maternal nutrient intake during early- and mid-gestation, pelvic area and hormonal indicators of placental function.

The influence of nutrition during the first and second trimesters of gestation on the occurrence of dystocia was investigated in 3-year-old composite-breed beef heifers. Heifers were allocated according to stratification by weight and genotype to either a high (H/-=76 MJ metabolisable energy (ME) and 1.4 kg crude protein (CP)), or low (L/-=62 MJ ME and 0.4 kg CP daily) nutritional treatment on the day of artificial insemination (day 0) to the same Senepol bull. Half of each nutritional group changed to an opposite nutritional group on day 93 of gestation (-/H=82 MJ ME and 1.4 kg CP; -/L=63 MJ ME and 0.4 kg CP daily), resulting in four treatment groups: HH (n=16); HL (n=19); LH (n=17); LL (n=19). From 180 days until calving all heifers were fed the same diets. Pelvic area measures were taken at heifer selection (-72 days) and at 117 days. Maternal circulating concentrations of estrone sulphate (ES), bovine placental lactogen (bPL), bovine pregnancy associated glycoprotein and progesterone were monitored throughout gestation. Heifers were observed continuously over the calving period and delivery type classified as being either eutocic or dystocic. The occurrence of dystocia was 14.1%. Increased calf birth weight increased the odds of occurrence of dystocia (odds ratio (OR)=1.40; 95% confidence interval (95% CI) 1.12-1.76; P<0.01). High diets in the second trimester were associated with heavier calves at birth (P=0.01). The mean pelvic area of eutocic heifers on -72 d, tended to be greater compared to that of dystocic heifers (P=0.08) such that a 1-cm(2) difference in pelvic area tended to decrease the risk of dystocia (OR=0.97; 95% CI 0.93-1.01; P=0.09). Longer gestation length was associated with an increased risk of dystocia (P=0.03). ES (P=0.04) and bPL (P=0.09) at calving were positively associated with the risk of dystocia. In conclusion, the current study demonstrates (a) that pelvic area measurement at selection in 3-year-old Bos indicusxBos taurus heifers may be useful for identifying heifers at an increased risk of dystocia and (b) increased ES and bPL concentrations at calving are associated with increased risk of dystocia. Pelvic area measurements obtained prior to conception remain valid in their assessment of the relationship between pelvic area and likelihood of dystocia occurring in the event of changing maternal nutrient intake during gestation. This is an important finding given maternal diets high in protein and energy during the second trimester of gestation increased calf birth weight and calf birth weight was associated with an increase in the occurrence of dystocia in heifers calving as 3-year olds.