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This study compared the sensitivity of peak running speed (PRS) measured during a submaximal run test (SRT) with a countermovement jump (CMJ) test to provide an alternate method of measuring neuromuscular fatigue (NMF). The study involved 20 semi-professional academy soccer players who performed a SRT and CMJ test, 24-hours pre-match, 24-, 48-, 72- and 96-hours post-match. Moderate decreases (effect-size (ES) +/- 90% confidence intervals) were observed 24-hours post-match for CMJ(H); ES -0.70 +/- 0.19, CMJ(PV); ES -0.92 +/- 0.27 and PRS; ES -0.58 +/- 0.11 with small decreases in CMJ(H); ES -0.36 +/- 0.13 and PRS; ES -0.27 +/- 0.23 still evident 48-hours post-match before returning to baseline 72-hours post-match. The results confirm PRS as an inexpensive alternate method of measuring NMF which, allows instantaneous real-time feedback on NMF. This can allow changes to be made immediately on-field within the post-match recovery phase without the need for further analysis or equipment.

Introduction: To determine whether combined exercise training with an energy-restricted diet leads to improved physical fitness and body composition when compared to energy restriction alone in free-living premenopausal women with clinically severe obesity. Methods: Sixty premenopausal women (BMI of 40.4 ± 6.7) were randomised to energy restriction only (ER) or to exercise plus energy restriction (EXER) for 12 months. Body composition and fitness were measured at baseline, 3, 6 and 12 months. Results: VO2 peak improved more for EXER compared to ER at 3 (mean difference ± SEM 2.5 ± 0.9 mL ∙ kg–1 ∙ min–1, p = 0.006) and 6 (3.1 ± 1.2 mL ∙ kg–1 ∙ min–1, p = 0.007) but not 12 months (2.3 ± 1.6 mL ∙ kg–1 ∙ min–1, p = 0.15). Muscle strength improved more for EXER compared to ER at all time points. No differences between groups for lean mass were observed at 12 months. Conclusion: Combining exercise training with an energy-restricted diet did not lead to greater aerobic power, total body mass, fat mass or limit lean body mass loss at 12 months when compared to energy restriction alone for premenopausal women with clinically severe obesity in free-living situations. Future research should aim to determine an effective lifestyle approach which can be applied in the community setting for this high-risk group.

Issue addressed: To deconstruct a personal account involving the initial decision making and ultimate consequences of driving under the influence of alcohol to educate drinkers about the realities of short- and long-term impacts associated with drink-driving. Methods: This qualitative study uses collaborative methods and draws on an autoethnographic (n = 1) account to identify multiple challenges and outcomes arising from a singular drink-driving incident. Results: Findings document how the split-second decision to drink and drive can give rise to unforeseen, ongoing and complex problems associated with injuries and pain management, the legal system, personal and professional costs, social isolation and shame. Conclusions: Many believe that driving ability is only affected if an individual is drunk, and that the ramifications of low-range drinking (blood alcohol concentration greater than 0.05 and less than 0.07) and driving are minimal and avoidable. This personal account emphasises the stark realities associated with such na€ive perceptions, particularly among young males, and augments efforts to dissuade drivers from drinking. So what? The experiential insights within this narrative account have the potential to help inform peer education programs and contribute to reductions in youth road trauma and associated injuries.

Objective Obesity is associated with a decline in health-related quality of life (HRQOL), while weight loss and exercise training have a positive influence. The aim of this systematic review was to compare the effects of energy restriction (ER) alone intervention to diet and exercise intervention on HRQOL. Methods MEDLINE, CINAHL and PsycINFO databases were searched for randomised controlled trials examining HRQOL through lifestyle interventions which examined ER and energy restriction plus exercise in obese adults. Results Nine hundred and fifty-two papers were assessed for inclusion in this review with nine being deemed suitable. This review indicates that four studies provide evidence to support the role of exercise in addition to ER to improve HRQOL in adults with obesity. The findings of this review are limited due to the limited number of studies as well as substantial heterogeneity in ER, exercise prescription variables and outcome measures utilised within studies. Conclusions A definitive conclusion regarding the capacity of exercise to facilitate greater improvement in HRQOL than diet alone, or, to formulate an exercise prescription for obese adults to address HRQOL is not feasible based on the existing evidence. Future studies should utilise comparable HRQOL assessment tools along with ensuring full reporting of results.

Summary Introduction Achieving continence in children with neurogenic sphincteric incompetence is a challenge. Awareness of the long-term outcome in this young patient population is important. In the past 25 years, the study institution has built experience in bladder outlet procedures such as bladder neck sling and bladder neck reconstructions. Objective The objective of this study was to evaluate the long-term outcome on continence and re-intervention rate of bladder outlet procedures in children with neurogenic urinary incontinence at the study institution. Design All children who underwent a bladder neck procedure between 1992 and 2017 at the study institution were retrospectively reviewed. Continence at the end of follow-up was the primary endpoint, defined as ‘dry’ when there was an interval of a minimum of 4 h without urinary leakage. Non-parametric tests were used for statistical analysis. Results During this 25-year period, a total of 60 children underwent a bladder outlet procedure, either a bladder neck sling (n = 43) or a bladder neck reconstruction (n = 17). The median age at surgery was 11.6 years (interquartile range [IQR] 7.8–13.9). Concomitant surgery consisted of bladder augmentation in 80% and continent catheterizable urinary channel in 97% of children. Dry rate within 1 year was 38%. After a median follow-up of 10.4 years (IQR 6.5–15.5), 77% of all children were dry. Twenty-five children (42%) needed one or more re-interventions, including redo of the bladder outlet procedure, other type of outlet procedure, bulking agents, bladder augmentation, and bladder neck closure. Discussion This study confirms that achieving continence is a challenge. The inconsistent use of the definition of urinary continence creates confusion in the literature and makes comparison of outcome with other studies difficult. Openness of (long-term) results in achieving urinary continence is important and helpful for future patients. Conclusion On the long term, the majority of children with neurogenic urinary incontinence were dry after a bladder outlet procedure, but a considerable number of patients had a re-intervention. The initial outcome on continence was slightly disappointing. Reporting long-term results is essential and helpful for patient counseling. Summary Table . Gender and continence outcome presented in number (%). Total n = 60 BNS n = 43 BNR n = 17 Difference between BNS and BNR Gender Female 35 (58%) 31 (72%) 4 (23.5%) Male 25 (42%) 12 (28%) 13 (77.5%) P a Continence outcome Dry rate 23 (38%) 15 (35%) 8 (47%) P = 0.382 a Dry rate > 1 yr follow-up 46 (77%) 33 (77%) 13 (77%) P = 0.982 a BNS, bladder neck sling; BNR, bladder neck reconstruction. a Chi-squared test.

Background Accelerometry is the method of choice for objectively assessing physical activity in older adults. Many studies have used an accelerometer count cut point corresponding to 3 metabolic equivalents (METs) derived in young adults during treadmill walking and running with a resting metabolic rate (RMR) assumed at 3.5 mL · kg−1 · min−1 (corresponding to 1 MET). RMR is lower in older adults; therefore, their 3 MET level occurs at a lower absolute energy expenditure making the cut point derived from young adults inappropriate for this population. The few studies determining older adult specific moderate-to-vigorous intensity physical activity (MVPA) cut points had methodological limitations, such as not measuring RMR and using treadmill walking. Methods This study determined a MVPA hip-worn accelerometer cut point for older adults using measured RMR and overground walking. Following determination of RMR, 45 older adults (mean age 70.2 ± 7 years, range 60–87.6 years) undertook an outdoor, overground walking protocol with accelerometer count and energy expenditure determined at five walking speeds. Results Mean RMR was 2.8 ± 0.6 mL · kg−1 · min−1. The MVPA cut points (95% CI) determined using linear mixed models were: vertical axis 1013 (734, 1292) counts · min−1; vector magnitude 1924 (1657, 2192) counts · min−1; and walking speed 2.5 (2.2, 2.8) km · hr−1. High levels of inter-individual variability in cut points were found. Conclusions These MVPA accelerometer and speed cut points for walking, the most popular physical activity in older adults, were lower than those for younger adults. Using cut points determined in younger adults for older adult population studies is likely to underestimate time spent engaged in MVPA. In addition, prescription of walking speed based on the adult cut point is likely to result in older adults working at a higher intensity than intended.

Background: Clinical practice guidelines globally recommend lifestyle modification including diet and exercise training as first-line treatment for obesity. The clinical benefits of exercise training in adults with obesity is well-documented; however, there is no strong evidence for the effectiveness of exercise training for weight loss in class II and class III obesity. The purpose of the randomised controlled trial described in this protocol article is to examine the effect of exercise training, in addition to a very low energy diet (VLED), in clinically severe obese women for changes in body composition, physical function, quality of life, and markers of cardiometabolic risk. Methods/Design: Sixty women, aged 18–50 years with a body mass index (BMI) greater than 34.9 kg.m2 and at least one obesity-related co-morbidity, will be recruited for this 12-month study. Participants will be randomised to either exercise plus energy restriction (n = 30), or energy restriction alone (n = 30). All participants will follow an energy-restricted individualised diet incorporating a VLED component. The exercise intervention group will also receive exercise by supervised aerobic and resistance training and a home-based exercise programme totalling 300 minutes per week. Primary outcome measures include body composition and aerobic fitness. Secondary outcome measures include: physical function, cardiometabolic risk factors, quality of life, physical activity, and mental health. All outcome measures will be conducted at baseline, 3, 6 and 12 months. Discussion: Previous research demonstrates various health benefits of including exercise training as part of a healthy lifestyle at all BMI ranges. Although clinical practice guidelines recommend exercise training as part of first-line treatment for overweight and obesity, there are few studies that demonstrate the effectiveness of exercise in class II and class III obesity. The study aims to determine whether the addition of exercise training to a VLED provides more favourable improvements in body composition, physical function, quality of life, and markers of cardiometabolic risk for women with clinically severe obesity, compared to VLED alone. Trial registration: Australian New Zealand Clinical Trials Registry (ACTRN12611000694910). Date registered: 4 July 2011

Objectives: Endothelin (ET) is a strong constrictor of smooth muscle structures. The relevance of Endothelin-A receptors in the bladder was demonstrated in several in vitro studies. The aim of this functional study was to evaluate the acute effect of the selective ET-A-antagonist LU 302146 (LU) on neurostimulation-induced bladder contractions in vivo. Methods: Eight male mini pigs were anesthesized. The bladder was exposed and a double lumen catheter was inserted to perform intravesical pressure (pves) measurements. Laminectomy was performed for sacral anterior root stimulation (SARS) of S2. Four animals received the selective ET-A-antagonist LU, three atropine and one animal was treated with vehicle. Pves was recorded before and after drug administration as well as before and during neurostimulation. At the end of each LU trial, a supplementary application of 4 mg atropine was administered followed by a final SARS. Results: In all experiments reproducible pves values were elicited during electrostimulation before administration of the test substance. The selective ET-A-antagonist reduced stimulation-induced bladder contraction by a mean of 57%. Additional administration of atropine inhibited the detrusor contraction almost completely during SARS. The vehicle had no effect on bladder contraction. Conclusions: In the presented animal model, ET-1 inhibition with the selective ET receptor-A-antagonist LU 302146 decreases stimulation-induced bladder contraction in vivo. The results suggest that the selective ET-A antagonist LU acts on the atropine-resistant component of efferent detrusor activation since additional administration of atropine almost completely abolish detrusor contraction. This observation in addition to the involvement of ET-1 in bladder smooth muscle proliferation, raises the possibility that ET-receptor antagonists might be beneficial in patients with neurogenic bladder dysfunction or in patients with functional or anatomical BOO.

Introduction An increased activity of the external urethral sphincter or pelvic floor muscles during voluntary voiding leads to dysfunctional voiding. Frequently reported symptoms are urinary incontinence, urinary tract infections and high post-void residuals. Dysfunctional voiding is a common problem in school-aged children and despite various treatment options, 10-40% of the children remain therapy-refractory. Objective The aim of this study is to evaluate the effectiveness of Onabotulinum toxin-A (BTX-A) injections in the external urethral sphincter in children with therapy-refractory dysfunctional voiding. Patients and methods Patients with therapy-refractory dysfunctional voiding who have received BTX-A injections in the external urethral sphincter from 2010 to 2013 were analysed. Children with known neuropsychiatric disorders were excluded. All children had abnormal flow patterns and increased pelvic floor tone during uroflowmetry/EMG studies. They had received at least five sessions of urotherapy and two sessions of pelvic floor physical therapy prior to treatment. A total of 100 IU of BTX-A was injected in the external urethral sphincter at the 3, 9 and 12 o'clock positions. Our main outcome measures were urinary incontinence, recurrent urinary tract infections and post-void residual. Results A total of twenty patients, of whom 16 girls, with a median age of 9 years (range 5-14) were treated with BTX-A. The median follow-up was 13 months (range 5-34). Post-void residual decreased by 75% after BTX-A, from a median of 47.5 ml (16.3-88.5 ml) to 0 ml (0.0-28.0 ml) (p = 0.001) Six patients had a post-void residual < 20 ml prior to treatment. After BTX-A sixteen patients had a post-void residual < 20 ml (Figure). No significant changes in uroflowmetry results was seen. Sixteen children are no longer daily incontinent, of whom 9 became completely dry (p = 0.0001). Eleven patients suffered from recurrent urinary tract infections prior to treatment. After BTX-A five children remained infection free, while the other six experienced only one urinary tract infection during follow-up (p = 0.003). Fourteen patients received additional urotherapy after BTX-A. Repeat injections were necessary in four patients after initial satisfactory results, with repeated good clinical responses. Two children showed no improvement after first BTX-A injection. No serious adverse events were reported. Discussion The results in this homogenous group of patients confirm the conclusions of previous studies in opting BTX-A in the external urethral sphincter to be a viable treatment option for the therapy-refractory group of patients with dysfunctional voiding. What is new, is that in most of our patients post-injection urotherapy was used to amplify the BTX-A effect. During our long-term follow-up the satisfactory results were sustained, similar to the results of the long-term follow-up presented by Vricella et al. [1]. The retrospective character and relative small sample size are limitations of this study. Conclusions This study shows safe and persistent satisfactory results during our average 13-month follow-up in 90% of our patients with therapy-refractory dysfunctional voiding. A prospective study using validated and standardized measurements will be performed to affirm our results and evaluate the exact role of post-injection urotherapy.

Diseases in childhood have an impact on growth. The influence of Langerhans cell histiocytosis (LCH) on growth has never been studied well. Recently a patient with LCH was treated with human growth hormone (GH) because of severe GH deficiency due to LCH involvement of both the hypothalamus and pituitary. This led us to review our charts from 1971 onward for evaluation of the growth patterns in patients with LCH. Here the long-term growth of 22 patients with LCH is reported, the median follow up being 7 years and 1 month. The height data were converted into standard deviation scores (SDS). At diagnosis the mean SDS of patients with isolated LCH at diagnosis was 0.04 and -0.37 in patients with disseminated LCH. Of the total group, 12 patients did not show any influence from the LCH or therapy on their growth. The remaining 10 patients reached, after a minimum of 3 years, a percentile clearly higher than that at diagnosis. However all the ten above mentioned patients, either isolated or disseminated LCH, had a lesion in the facial side of the skull. CONCLUSION. GH deficiency is not a common manifestation of LCH in childhood and GH provocation tests are only indicated when there is a poor or decelerating growth rate. In our patients the number of organs involved and/or the treatment modality did not influence the growth in all but one.

Reported here is the case of a 5-year old boy with a pyeloureteral junction (PUJ) obstruction and pyelonephritis caused by Actinobaculum schaalii, an Actinomyces-like organism. Pyelonephritis or any other urinary tract infection caused by Actinobaculum schaalii has not been described in children before. The patient responded well to pyeloplasty in combination with antibiotic treatment.

We devised a technique for phalloplasty in a female-to-male transsexual combining the lateral upper arm free flap with a bladder mucosa graft, to address the ideal requirements of phalloplasty in the best possible way. The surgical techniques are described. Healing of the phallus has been uneventful, but postoperative bladder spasms, meatal stenosis, and an intraurethral valve were encountered. The cosmetic result of the phalloplasty is pleasing. Sensibility is still increasing after a 14-month follow-up. Scarring of the upper arm donor site can be camouflaged easily. Although the actual phalloplasty as described in this article is a one-stage microsurgical procedure that appears to be reproducible, the construction of a phallus meeting all requirements still implies more than one stage.

Contains fulltext : 79985.pdf (Publisher’s version ) (Closed access) Chromosome analysis in two young patients with multiple congenital anomalies revealed a de novo interstitial deletion of 8q that has not been reported before. The deletions were overlapping by 8.35 Mb (8q24.21q24.23). The clinical features shared by our patients were coloboma, VSD, digital abnormalities, congenital dislocation of a hip, feeding problems, psychomotor delay and convulsions. The deletion included the region for Langer-Giedion syndrome (TRPS1 and EXT1) in the girl only. However, she is too young to present features of this syndrome, apart from dysmorphic features like a bulbous nose and notched alae nasi. Several genes are present in the commonly deleted region, including genes with unknown function, and genes for which haploinsufficiency is known to have no phenotypic effect in mice (Wnt1). A gene that might play a role in the convulsions of our patients is KCNQ3.

Heart failure is a life-threatening complication of fulminant meningococcal septic shock (MSS). Depression of left ventricular function, in particular, is thought to be due to circulating meningococcal endotoxin. Myocardial failure leads to ventricular dilation expressed by an increased left-ventricle end-diastolic diameter (LVED). With ultrasonography, LVED can be accurately measured as well as the shortening fraction (SF). In an evaluative study we investigated the accuracy of the SF and compared it to the accuracy of the Glasgow meningococcal septicemia prognostic score (GMSPS) in the prediction of mortality in children with fulminant MSS. In 27 children admitted in a 4-year period with a presumptive clinical diagnosis of fulminant MSS, hypotension persisted for more than 1 h despite volume loading and inotropic therapy. Seven of these children died (26%); all had an SF or =10 (the sensitivity of both scores was 100%). Positive predictive values of the SF and GMSPS were 41% and 58% respectively. CONCLUSIONS: SF can be used in addition to other severity scores in clinical decision-making and contribute to the selection of children with the worst prospects for inclusion in experimental treatment studies

A significant increase in the incidence of caseous lesions in the lymph nodes of slaughter pigs prompted a large-scale investigation in five slaughterhouses in The Netherlands. In total, 158,763 pigs from 2,899 groups underwent gross examination. At least one pig with caseous lesions in the submaxillary and/or mesenteric lymph nodes was observed in each of 154 of the 2,899 groups examined (5%). In total, 856 pigs (0.5%) were affected. As many as five pigs in each of 141 of the 154 positive groups (91.5%) had lymph node lesions. Greater numbers of pigs with affected lymph nodes were found in 13 groups (8.5%). Four pigs had lesions in the kidneys, liver, or spleen. Acid-fast bacteria were detected by microscopic examination of 121 of 292 Ziehl-Neelsen-stained smears of caseous lesions (41%). In a follow-up study, Mycobacterium avium complex (MAC) bacteria were isolated from 219 of 402 affected lymph nodes (54.2%). Ninety-one of the isolated strains were analyzed by restriction fragment length polymorphism (RFLP) typing with insertion sequence IS 1245 as a probe. All but 1 of these 91 strains contained IS 1245 DNA, indicating that pigs in The Netherlands carried almost exclusively M. avium bacteria and no other bacteria of MAC. Only one pig isolate exhibited the bird-type RFLP pattern. MAC isolates from 191 human patients in The Netherlands in 1996 were also typed by RFLP analysis. Computer-assisted analysis showed that the RFLP patterns of 61% of the human isolates and 59% of the porcine isolates were at least 75% similar to the RFLP patterns of the other group of strains. This indicates that pigs may be an important vehicle for M. avium infections in humans or that pigs and humans share common sources of infection.

The 9 cows used in the preceding trial [see DSA 39, 2470] were allocated during the dry period (approx. 8 wk) to 3 levels of aldrin, heptachlor and beta -hexachlorocyclohexane ( beta -BHC) mixed with the concentrate ration. The daily dosages/cow were (i) 0.5, (ii) 1 or (iii) 2 mg of each pesticide. Because the date of parturition could only be predicted roughly, the dry period/cow varied resulting in large differences in total doses for cows within a group; mean total dose of each pesticide was (i) 26, (ii) 56 and (iii) 87 mg/cow. The pesticide levels in milk fat after parturition did not only represent the effect during the dry period because the cows had also been dosed with pesticides late in the preceding lactation. Aldrin and heptachlor residues in milk fat were below the detection limit of 0.01 mg/kg and content of beta -heptachlor epoxide was

Deposition of radiocaesium from the Chernobyl reactor accident on the Netherlands made it possible to collect contaminated fresh grass and first cut wilted grass silage. These contaminated roughages were used in transfer experiments with lactating dairy cows to determine transfer coefficients and half-lives for Cs-137 in milk. The experimental design was based on three consecutive periods: a preliminary period to determine the background concentration of the isotope in milk, a contamination period to determine the magnitude of accumulation and finally a depletion period to measure the rate at which the activity concentration of Cs-137 in milk declined after continuous feeding. The average transfer coefficient (Fmilk) for cows fed on contaminated dried grass under steady-state conditions was 0.002 d/kg and for cows fed on slightly contaminated second cut fresh grass 0.006 d/kg. The highest transfer coefficients were obtained for cows fed on contaminated grass silage for 119 days, which also included the dry period of about two months. For the first five days after calving the Fmilk values varied from 0.0066 to 0.0091 d/kg. There were no significant differences in transfer coefficients between cows in early lactation (third month of lactation), cows in late lactation (the last month of the lactation period) and cows fed on both contaminated grass silage and uncontaminated maize silage simultaneously. Half-life values for the rate of decline of the isotope in milk during the depletion period were estimated on the basis of a mathematical model with two exponential components. These components were characterized by half-lives of 0.5 to 3.5 days and 10 to 46 days.

1. To investigate the transfer of aldrin, heptachlor and beta -hexachlorocylohexane ( beta -HCH) from feed to milk and body fat of dairy cows, 9 cows early and 9 cows late in lactation were assigned to groups of 3 and given different daily dosages of a mixture of pesticides: 1 mg, 2 mg or 4 mg each of aldrin, heptachlor and beta -HCH/cow daily for 4 weeks. Milk fat and body fat samples were analysed for pesticide content. Aldrin and heptachlor could not be detected in milk fat or in body fat. Average contents of beta -heptachlorepoxide were below 0.1 mg/kg even for the highest dosage. The beta -HCH and dieldrin contents in milk fat increased rapidly. The ratio of contents between the groups roughly corresponded to that between the dosages. The cows early in lactation did not have less beta -HCH and dieldrin than the cows late in lactation. During the first 14 days after withdrawal the contents of beta -HCH and dieldrin usually decreased by more than half. The average transfer coefficients for cows late in lactation were all below 10% and for cows early in lactation about 3 times as high, because yield of milk fat was nearly 3 times as high early in lactation. The pesticide contents in body fat too increased but did not reach the same level as in milk fat. Cows early in lactation usually had higher contents in body fat than cows late in lactation. An estimate of the average relative mass of beta -HCH and dieldrin in milk fat and body fat is given. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Pregnant sows were given tritiated water at two different doses (0.517 and 1.53 mCi/liter) during pregnancy and for 43 days thereafter (a total of 120 days). Some of the young pigs were left with their mother while the others were exchanged with uncontaiminated newborn to follow tritium oxide and organic tritium in different organs with respect to (a) continuing uptake, (b) uptake from milk, and (c) loss of activity after birth. Turnnover time of tritium oxide in adult sows is almost 10 days, and that in young pigs is about 8 days. In addition, components (less than or equal to 5%) of slower turnover are present. At equilibrium, the relative specific activity (i.e., the ratio of specific activity of tritium oxide isolated either directly or after combustion or organic matter to the specific activity of tritiated water ingested) is about 0.7 for body water in adult and newborn pigs and about 0.14 for organic tritium in most tissues. It is somewhat higher (0.22) in the brain of newborns than in other tissues. Turnover time for organic tritium in young pigs is longest in brain (59 days) and slower in muscular tissues (28 days), kidney, spleen, and pancreas (22 days), andmore » liver and intestine (17 days). From the data presented it is estimated that the contribution of organic tritium to the integral tissue dose is on the order of one-third to two-thirds of that from tritium oxide alone, except in the case of brain, where the contribution to the dose from organic tritium may equal or even exceed that from tritium oxide.« less

Two lactating cows were given tritiated hay containing organically bound tritium (OBT) only for about 4 weeks. Tritium activity was determined in milk fat, casein, lactose, milk water, and whole milk. In one cow, milk was sampled for approximately 450 days, covering two lactation periods. At steady state, specific tritium activities in casein, lactose, and milk water were 58, 10, and 11%, respectively, of those in milk fat. Some OBT was converted into THO during catabolism and entered the body water pool. This 3H source accounted for nearly 40% of tritium in lactose, but in casein and milk fat about 97% of tritium was derived from ingested OBT. Comparison of the specific activity of milk constituents with the specific activity of ingested hay showed the following values: 0.84 for milk fat, 0.49 for casein, 0.05 for lactose, 0.10 for milk water. About one-half of the tritium transferred to milk was found in organic milk constituents and the other half in milk water. Decrease of tritium activity with time could be represented by three components with different half-lives for the organic milk constituents. Those for milk fat and casein were quite similar, with a slow component of nearly 3 months.