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Concept: Weaning


BACKGROUND: Despite resolution of the symptoms of eating and/or swallowing disorders, prolonged tube feeding is maintained in some children. This study summarized the characteristics of children with tube dependence and investigated the causes of tube dependence. METHODS: Clinical and growth data were evaluated using medical records and referral forms for 35 tube-dependent children. RESULTS: The children in this study had a median age of 30 months (range, 17-37 months) on the first visit and 35.5 months (range, 21.3-44.8 months) at tube removal. Seven children were not weaned from the feeding tube within the study period. Twenty-two (63%) of the children were girls, 20 (57%) were able to walk, 24 (69%) had mild mental retardation, and 33 (94%) had underlying disease. Tube-dependent children tended to weigh less than age-matched normal children. Sixteen (45.7%) children were underweight. Children who had their feeding tubes removed before age 3 were significantly younger at the initial visit than those who had their tubes removed after 3 years of age. Increased finger feeding was observed during the period before tube removal. CONCLUSION: tube-dependent children tend to be close to normal in body growth and intellectual development. When weaning from tube feeding, interventions at earlier ages are more efficient. Reduction in or discontinuation of tube feeding and encouraging feeding self were effective to wean off tube feeding.

Concepts: Weaning, Mental retardation, Feeding tube


Abstract Objective: The aim of the study is to evaluate the application of Neurally Adjusted Ventilatory Assist (NAVA) in the respiratory weaning of patients affected by congenital diaphragmatic hernia (CDH). Methods: We analyzed the NAVA weaning in 12 neonates affected by CDH, relating the effectiveness of the electrical activation of the diaphragm (EAdi) signal to the type of CDH repair (with or without patch), the size of the patch, the stomach and His angle position, and the trend evaluation of some cardio-respiratory parameters with NAVA compared to pressure-support-ventilation (PSV). Results: 5 neonates submitted to primary repair showed a regular EAdi signal and were successfully weaned with NAVA. Of the 7 patients submitted to patch repair, 5 operated with patch limited to the diaphragmatic postero-lateral area had an active EAdi signal that permitted weaning with NAVA. Only in 2 neonates with hemidiaphragm agenesis was NAVA not feasible due to the impossibility to capture the EAdi signal. Compared to PSV, NAVA allows a significant improvement of oxygenation-linked indexes and paCO(2), while PIP is reduced. Conclusion: Neonatal CDH with a postero-lateral diaphragmatic defect allows the NAVA catheter to obtain a correct EAdi signal and develop a viable NAVA ventilation. The lower risk of lung injury in NAVA appears compatible with current ventilatory strategies considered useful in CDH.

Concepts: Weaning, Respiration, Diaphragm, Breastfeeding, Congenital diaphragmatic hernia, Milk, Respiratory system, Thoracic diaphragm


Early-life dietary transitions reflect fundamental aspects of primate evolution and are important determinants of health in contemporary human populations. Weaning is critical to developmental and reproductive rates; early weaning can have detrimental health effects but enables shorter inter-birth intervals, which influences population growth. Uncovering early-life dietary history in fossils is hampered by the absence of prospectively validated biomarkers that are not modified during fossilization. Here we show that large dietary shifts in early life manifest as compositional variations in dental tissues. Teeth from human children and captive macaques, with prospectively recorded diet histories, demonstrate that barium (Ba) distributions accurately reflect dietary transitions from the introduction of mother’s milk through the weaning process. We also document dietary transitions in a Middle Palaeolithic juvenile Neanderthal, which shows a pattern of exclusive breastfeeding for seven months, followed by seven months of supplementation. After this point, Ba levels in enamel returned to baseline prenatal levels, indicating an abrupt cessation of breastfeeding at 1.2 years of age. Integration of Ba spatial distributions and histological mapping of tooth formation enables novel studies of the evolution of human life history, dietary ontogeny in wild primates, and human health investigations through accurate reconstructions of breastfeeding history.

Concepts: Evolution, Demography, Breastfeeding, Weaning, Nutrition, World population, Primate, Human


Childhood is a unique stage in human life history, in which subadults have completed their weaning process but are still dependent on older individuals for survival. Although the importance of food provisioning during childhood has been intensively discussed, childhood diet in the past has rarely been studied in a systematic manner.

Concepts: Past, Weaning, Chemical element, World population, Human


Parenteral nutrition (PN) dependence in short bowel syndrome (SBS) patients is linked to the functionality of the remnant small bowel (RSB). Patients may wean off PN following a period of intestinal adaptation that restores this functionality. Currently, plasma citrulline is the standard biomarker for monitoring intestinal functionality and adaptation. However, available studies reveal that the relationship the biomarker with the length and function of the RSB is arguable. Thus, having additional biomarkers would improve pointing out PN weaning.

Concepts: Weaning, Function, Biomarker, Lacteal, Intestine, Large intestine, Small intestine


Concentrations of HIV-1 RNA and DNA in mucosal compartments influence the risk of sexual transmission and mother-to-child transmission of HIV-1. Breast milk production is physiologically regulated such that supply is a function of infant demand, but whether demand also influences HIV-1 dynamics in breast milk is unknown. We tested whether minor and major changes in feeding frequency influence breast milk viral concentrations in 958 HIV-1-infected women and their infants followed, for 24 months during a trial in Lusaka, Zambia. Women were randomized to wean abruptly at 4 months or to continue breast-feeding for a duration of their own choosing. Two weeks after breast-feeding cessation (4.5 months), HIV-1 concentrations in breast milk were substantially higher (median RNA, 2708 copies/ml; DNA, 14 copies/ml) than if breast-feeding continued (median RNA, <50 copies/ml; DNA, <1 copy/ml; P < 0.0001). Among those continuing breast-feeding, HIV-1 concentrations in milk were higher if breast-feeding was nonexclusive (median RNA, 293 copies/ml; DNA, 2 copies/ml; P = 0.0006). Elevated milk viral concentrations after stopping breast-feeding explained higher than expected rates of late postnatal HIV transmission in those who weaned early. Changes in the frequency of breast-feeding peri-weaning and with nonexclusive breast-feeding influenced milk viral concentrations. This may explain the reduced risk of HIV-1 transmission associated with exclusive breast-feeding and why early weaning does not achieve the magnitude of HIV prevention predicted by models. Our results support continuation of maternal antiretroviral drug interventions over the full duration of time when any breast milk exposures may occur after planned weaning.

Concepts: AIDS, Prolactin, Infant, Weaning, Breastfeeding, Milk, HIV, Breast milk


Dairy calves weaned off milk at an early age show signs of hunger and can lose weight. We examined whether using automated feeders to wean calves according to individual voluntary solid feed intake reduced the effects of weaning. Female Holstein calves were housed in groups of 5 to 9. All calves were fed 12 L/d milk and ad libitum grain starter and hay from automated feeders immediately after grouping, and were allocated to 3 weaning strategies: (1) early-weaned (EW; n = 14): weaning began on d 40, and milk allowance gradually decreased until weaning was complete on d 48; (2) late-weaned (LW; n = 14): weaning began on d 80 and was completed on d 89; (3) weaned by starter intake (WSI; n = 28): weaning began when calves consumed 200 g/d of starter and was completed when the calves consumed 1,400 g/d. Each day, the automated feeders recorded quantities of milk, starter, and hay eaten by all calves, as well as the frequency of visits to the milk feeder; we used unrewarded visit frequency as a sign of hunger. Body weights (BW) were recorded weekly. We estimated daily digestible energy (DE) intake for each calf based on the milk, hay, and starter consumed. Average daily gains (ADG) were expressed as percent of BW. For calves in WSI, weaning began at 54.7 ± 18.9 d (mean ± SD) of age, the duration of weaning was 21.1 ± 10.6 d, and weaning ended at 75.8 ± 10.7 d of age. Both LW and WSI calves had better ADG from wk 3 to 13 than EW calves. Calves in the WSI group drank less milk and ate more starter than LW calves but had similar ADG. During the period of weaning, EW calves made more unrewarded visits to the milk feeder than LW and WSI calves. Three EW calves lost weight during weaning, whereas all LW and WSI calves gained weight. Calves differ greatly in when they begin to eat solid feed and how quickly they increase the intake in response to a decrease in milk allowance. An advantage of automated feeders is that calves can be weaned at variable ages depending on their ability and willingness to eat solid feed, which reduces signs of hunger and improves weight gains during weaning.

Concepts: Nutrition, Cattle, Dairy farming, Breast milk, Lactose intolerance, Weaning, Milk


IMPORTANCE Patients requiring prolonged mechanical ventilation (>21 days) are commonly weaned at long-term acute care hospitals (LTACHs). The most effective method of weaning such patients has not been investigated. OBJECTIVE To compare weaning duration with pressure support vs unassisted breathing through a tracheostomy collar in patients transferred to an LTACH for weaning from prolonged ventilation. DESIGN, SETTING, AND PARTICIPANTS Between 2000 and 2010, a randomized study was conducted in tracheotomized patients transferred to a single LTACH for weaning from prolonged ventilation. Of 500 patients who underwent a 5-day screening procedure, 316 did not tolerate the procedure and were randomly assigned to receive weaning with pressure support (n = 155) or a tracheostomy collar (n = 161). Survival at 6- and 12-month time points was also determined. MAIN OUTCOME MEASURE Primary outcome was weaning duration. Secondary outcome was survival at 6 and 12 months after enrollment. RESULTS Of 316 patients, 4 were withdrawn and not included in analysis. Of 152 patients in the pressure-support group, 68 (44.7%) were weaned; 22 (14.5%) died. Of 160 patients in the tracheostomy collar group, 85 (53.1%) were weaned; 16 (10.0%) died. Median weaning time was shorter with tracheostomy collar use (15 days; interquartile range [IQR], 8-25) than with pressure support (19 days; IQR, 12-31), P = .004. The hazard ratio (HR) for successful weaning rate was higher with tracheostomy collar use than with pressure support (HR, 1.43; 95% CI, 1.03-1.98; P = .033) after adjusting for baseline clinical covariates. Use of the tracheostomy collar achieved faster weaning than did pressure support among patients who did not tolerate the screening procedure between 12 and 120 hours (HR, 3.33; 95% CI, 1.44-7.70; P = .005), whereas weaning time was equivalent with the 2 methods in patients who did not tolerate the screening procedure within 0 to 12 hours. Mortality was equivalent in the pressure-support and tracheostomy collar groups at 6 months (55.92% vs 51.25%; 4.67% difference, 95% CI, -6.4% to 15.7%) and at 12 months (66.45% vs 60.00%; 6.45% difference, 95% CI, -4.2% to 17.1%). CONCLUSION AND RELEVANCE Among patients requiring prolonged mechanical ventilation and treated at a single long-term care facility, unassisted breathing through a tracheostomy, compared with pressure support, resulted in shorter median weaning time, although weaning mode had no effect on survival at 6 and 12 months. TRIAL REGISTRATION Identifier: NCT01541462.

Concepts: Activities of daily living, Nursing home, Long-term care, Hour, Weaning, Time, Randomized controlled trial, Interquartile range


The main objective of this research was to conduct an exploratory study of the lactation curve in order to characterize the productive potential of Pantaneiro ewes and lambs. Fifty ewes were bred using four rams in two different mating seasons. The ewes were kept with their lambs on pasture of Brachiaria brizantha. Ewe body score, ewe weight, and lamb weight were evaluated. Milk sampling was performed every week. In the morning for milk collections, the ewes were treated with 1 UI of oxytocin (intramuscular) for complete milking. Lambs were separated from the ewes for 4 h and milk collections were performed. The total milk production over 24 h was estimated by multiplying the production of this period (4 h) by 6. The data were analyzed using the MIXED procedure (P < 0.05) in SAS. Milk production data were fitted to the curve using the incomplete gamma function of Wood, and lamb growth data were fitted using the Gompertiz equation. The average milk production of the ewes was 1.03 kg/day-1. Younger ewes had the lowest milk production (18 = 798 ± 330, 24 = 1001 ± 440, 36 = 1100 ± 490, and 48 = 1106 ± 490 g/day-1). Ewe body score at lambing affected initial milk production (1.0 = 816 ± 660, 1.5 = 1089 ± 105, and 2.0 = 1424 ± 1600 g/day-1). Lambs were weaned with an average weight of 20.3 kg. Daily weight gain from birth to weaning was 181 g. Locally adapted Pantaneiro ewes showed a linear decreasing lactation curve, with reduced production from the second week of lactation. Overall, evaluation of the dairy production and lamb performance revealed great variation, denoting potential for selection.

Concepts: Dairy farming, Weaning, Domestic sheep, LaMB, Cattle, Breast milk, Dairy, Milk


The objective of this study was to evaluate the effects of preweaning total plane of milk intake and weaning age on intake, growth performance, and blood metabolites of dairy calves. A total of 48 Holstein calves (40 ± 1.6 kg of body weight) were used in a 2 × 2 factorial arrangement with the factors of weaning age (d 60 vs. 75) and the total plane of milk intake (medium vs. high) during the preweaning period. Calves were assigned to 1 of 4 treatments: (1) calves fed medium plane of milk (MPM) intake and weaned on d 60 of age (MPM-60d, 4 L/d of milk from d 3 to 10, 6 L/d of milk from d 11 to 55, and 3 L/d of milk from d 56 to 60 of age; total milk intake = 317 L), (2) calves fed MPM intake and weaned on d 75 of age (MPM-75d, 4 L/d of milk from d 3 to 10 and 4.5 L/d of milk from d 11 to 70 of age followed by feeding 2.25 L/d of milk from d 71 to 75 of age; total milk intake = 313 L), (3) calves fed high plane of milk (HPM) intake and weaned on d 60 of age (HPM-60d, 4 L/d of milk from d 3 to 10, 6 L/d of milk from d 11 to 20, and 8.5 L/d of milk from d 21 to 55 followed by feeding 4.25 L/d of milk from d 56 to 60 of age; total milk intake = ∼411 L); and (4) calves fed HPM intake and weaned on d 75 (HPM-75d, 4 L/d of milk from d 3 to 10, and 6 L/d of milk from d 11 to 70 of age followed by feeding 3 L/d of milk from d 71 to 75 of age; total milk intake = 407 L) with no milk refusals. All of the calves were monitored up to d 90 of age. Regardless of weaning age, starter feed intake and dry matter intake (% of body weight) were lower in calves fed HPM compared with those receiving MPM. A tendency for the plane of milk intake × weaning age interaction was observed for metabolizable energy intake with the highest value was recorded with the HPM-75d calves. The lowest efficiency of metabolizable energy intake and average feed efficiency was observed in HPM-60d calves throughout the experimental period as compared with the other groups. An interaction was found between the total plane of milk intake and weaning age regarding effects on total average daily gain, average daily gain/metabolizable energy intake, feed efficiency, final body weight, and plasma β-hydroxybutyrate levels with the highest values measured in HPM-75d calves. Weaning on d 75 versus d 60 improved wither height and hip width, which tended to increase body length at the end of the trial. The results suggest that calves fed high amounts of milk during their preweaning period benefit from extending the time of weaning from 60 to 75 d of age based on average daily gain, feed efficiency, and final body weight.

Concepts: Plane, Cattle, Mass, Breast milk, Lactose intolerance, Dairy farming, Weaning, Milk