Calculation of new enteric methane emission factors for small ruminants in western Kenya highlights the heterogeneity of smallholder production systems

Context African livestock play a critical role in food security and the wider economy, while accounting for >70% of African agricultural greenhouse gas emissions. Accurate estimates of greenhouse gas emissions from livestock are required for inventory purposes and to assess the efficacy of mitigation measures. While there is an increasing number of studies assessing methane (CH4) emissions of cattle, little attention has been paid to small ruminants (SR). Aims Enteric CH4 emissions were assessed from 1345 SR in three counties of western Kenya to develop more accurate emission factors (EF) for enteric CH4 from sheep and goats. Methods Using on-farm animal activity data, feed samples were also analysed to produce estimates of feed digestibility by season and region. The combined data were also used to estimate daily CH4 production by season, location and class of animal to produce new EF for annual enteric CH4 production of SR. Key results Mean dry-matter digestibility of the feed basket was in the range of 58–64%, depending on region and season (~10% greater than Tier I estimates). EF were similar for sheep (4.4 vs 5 kg CH4/year), but lower for goats (3.7 vs 5 kg CH4/year) than those given for SR in developing countries in Intergovernmental Panel on Climate Change (Tier I) estimates. Conclusions Published estimates of EF for SR range widely across Africa. In smallholder systems in western Kenya, SR appear to be managed differently from cattle, and EF appear to be driven by different management considerations. Implications The findings highlighted the heterogenous nature of SR enteric emissions in East Africa, but also suggested that emissions from SR are quantitatively less important than other estimates suggest compared with cattle.

Simple and robust algorithms to estimate liveweight in African smallholder cattle

Measurement of liveweight of stock is one of the most important production tools available to farmers – playing a role in nutrition, fertility management, health and marketing. Yet most farmers in sub-Saharan Africa do not have access to scales on which to weigh cattle. Heart girth measurements (and accompanying algorithms) have been used as a convenient and cost-effective alternative to scales, however despite a plethora of studies in the extant literature, the accuracy and sensitivity of such measures are not well described. Using three datasets from phenotypically and geographically diverse cattle populations, we developed and validated new algorithms with similar R2 to extant studies but lower errors of prediction over a full range of observed weights, than simple linear regression, that was valid for measurements in an unassociated animal population in sub-Saharan Africa. Our results further show that heart girth measurements are not sufficiently sensitive to accurately assess seasonal liveweight fluctuations in cattle and thus should not be relied on in situations where high precision is a critical consideration.

Evaluation Of Mycotoxin Content In Soybean (Glycine max L.) Grown In Rwanda

Soybean is a critical food and nutritional security crop in Rwanda. Promoted by the Rwandan National Agricultural Research System for both adults and as an infant weaning food, soybean is grown by approximately 40% of households. Soybean may be susceptible to the growth of mycotoxin-producing moulds; however, data has been contradictory. Mycotoxin contamination is a food and feed safety issue for grains and other field crops. This study aimed to determine the extent of mycotoxin contamination in soybean, and to assess people's awareness on mycotoxins. A farm-level survey was conducted in 2015 within three agro-ecological zones of Rwanda suitable for soybean production. Soybean samples were collected from farmers (n=300) who also completed questionnaires about pre-and post-harvest farm practices, and aflatoxin awareness. The concentration of total aflatoxin in individual soybean samples was tested by enzymelinked immunosorbent assay (ELISA) using a commercially-available kit. Other mycotoxins were analyzed using liquid chromatography-mass spectrometry (LCMS/MS) on 10 selected sub samples. Only 7.3% of the respondents were aware of aflatoxin contamination in foods, but farmers observed good postharvest practices including harvesting the crop when the pods were dry. Using enzyme-linked immunosorbent assay (ELISA), only one sample had a concentration (11 µg/kg) above the most stringent EU maximum permitted limit of 4 µg/kg. Multi-mycotoxins liquid chromatography-mass spectrometry (LC-MS/MS) results confirmed that soybeans had low or undetectable contamination; only one sample contained 13µg/kg of sterigmatocystine. The soybean samples from Rwanda obtained acceptably low mycotoxin levels. Taken together with other studies that showed that soybean is less contaminated by mycotoxins, these results demonstrate that soybean can be promoted as a nutritious and safe food. However, there is a general need for educating farmers on mycotoxin contamination in food and feed to ensure better standards are adhered to safeguard the health of the consumers regarding these fungal secondary metabolites.

Once-a-day Concerta methylphenidate versus three-times-daily methylphenidate in laboratory and natural settings

OBJECTIVE

Methylphenidate (MPH), the most commonly prescribed drug for attention-deficit/hyperactivity disorder (ADHD), has a short half-life, which necessitates multiple daily doses. The need for multiple doses produces problems with medication administration during school and after-school hours, and therefore with compliance. Previous long-acting stimulants and preparations have shown effects equivalent to twice-daily dosing of MPH. This study tests the efficacy and duration of action, in natural and laboratory settings, of an extended-release MPH preparation designed to last 12 hours and therefore be equivalent to 3-times-daily dosing.

METHODS

Sixty-eight children with ADHD, 6 to 12 years old, participated in a within-subject, double-blind comparison of placebo, immediate-release (IR) MPH 3 times a day (tid), and Concerta, a once-daily MPH formulation. Three dosing levels of medication were used: 5 mg IR MPH tid/18 mg Concerta once a day (qd); 10 mg IR MPH tid/36 mg Concerta qd; and 15 mg IR MPH tid/54 mg Concerta qd. All children were currently medicated with MPH at enrollment, and each child's dose level was based on that child's MPH dosing before the study. The doses of Concerta were selected to be comparable to the daily doses of MPH that each child received. To achieve the ascending rate of MPH delivery determined by initial investigations to provide the necessary continuous coverage, Concerta doses were 20% higher on a daily basis than a comparable tid regimen of IR MPH. Children received each medication condition for 7 days. The investigation was conducted in the context of a background clinical behavioral intervention in both the natural environment and the laboratory setting. Parents received behavioral parent training and teachers were taught to establish a school-home daily report card (DRC). A DRC is a list of individual target behaviors that represent a child's most salient areas of impairment. Teachers set daily goals for each child's impairment targets, and parents provided rewards at home for goal attainment. Each weekday, teachers completed the DRC, and it was used as a dependent measure of individualized medication response. Teachers and parents also completed weekly standardized ratings of behavior and treatment effectiveness. To evaluate the time course of medication effects, children spent 12 hours in a laboratory setting on Saturdays and medication effects were measured using procedures and methods adapted from our summer treatment program. Measures of classroom behavior and academic productivity/accuracy were taken in a laboratory classroom setting during which children completed independent math and reading worksheets. Measures of social behavior were taken in structured, small-group board game settings and unstructured recess settings. Measures included behavior frequency counts, academic problems completed and accuracy, independent observations, teacher and counselor ratings, and individualized behavioral target goals. Reports of adverse events, sleep quality, and appetite were collected.

RESULTS

On virtually all measures in all settings, both drug conditions were significantly different from placebo, and the 2 drugs were not different from each other. In children's regular school settings, both medications improved behavior as measured by teacher ratings and individualized target behaviors (the DRC); these effects were seen into the evening as measured by parent ratings. In the laboratory setting, effects of Concerta were equivalent to tid MPH and lasted at least through 12 hours after dosing. Concerta was significantly superior to tid MPH on 2 parent rating scores, and when asked, more parents preferred Concerta than preferred tid IR MPH or placebo. Side effects on children's sleep and appetite were similar for the 2 preparations. In the lab setting, both medications improved productivity and accuracy on arithmetic seatwork assignments, disruptive and on-task behavior, and classroom rule following. Both medications improved children's rule following and negative behavior in small group board games, as well as in unstructured recess settings. Individual target behaviors also showed significant improvement with medication across domains in the laboratory setting. Children's behavior across settings deteriorated across the laboratory day, and the primary effect of medication was to prevent this deterioration as the day wore on. Results support the use of background behavioral treatment in clinical trials of stimulant medication, and illustrate the utility of a measure of individualized daily target goals (ie, the DRC) as an objective measure of medication response in both the laboratory and natural school settings.

CONCLUSION

This investigation clearly supports the efficacy of the Concerta long-acting formulation of MPH for parents who desire to have medication benefits for their child throughout the day and early evening. (ABSTRACT TRUNCATED)

A comparison of morning-only and morning/late afternoon Adderall to morning-only, twice-daily, and three times-daily methylphenidate in children with attention-deficit/hyperactivity disorder

OBJECTIVE

1) To compare standard twice-daily methylphenidate (MPH) dosing with a single morning dose of MPH and of Adderall during a typical school-day time period, and 2) to conduct a dose-response study of the effects of a late-afternoon (3:30 PM) dose of MPH and Adderall on evening behavior and side effects.

DESIGN

Within-subject, placebo-controlled, crossover design.

SETTING

Intensive summer treatment program with a comprehensive behavioral approach.

STUDY PARTICIPANTS

Twenty-one children with attention-deficit/hyperactivity disorder (19 boys and 2 girls), between the ages of 6 and 12 years.

INTERVENTIONS

Children received, in random order with daily crossovers, each of the following conditions: 1) placebo, 2) 0.3 mg/kg of MPH received 3 times, 3) 0.3 mg/kg of MPH received twice (7:30 AM and 11:30 AM) with 0.15 mg/kg received at 3:30 PM, 4) 0.3 mg/kg of MPH received once in the morning only, 5) 0.3 mg/kg of Adderall received at 7:30 AM and at 3:30 PM, 6) 0.3 mg/kg of Adderall once in the morning with 0.15 mg/kg received at 3:30 PM, 7) 0.3 mg/kg of Adderall received in the morning only.

OUTCOME MEASURES

Daily rates of behaviors in social and academic settings, and standardized ratings from counselors and teachers, were assessed for the hours between 8:00 AM and 3:30 PM (a typical school-day). Relative sizes of the medication effects were compared hourly between first daily ingestion (7:30 AM) and 4:45 PM to assess the time course of the 2 drugs. Effects of the 3:30 PM doses on functioning in the evenings at home were evaluated using parent ratings of behavioral and side effects.

RESULTS

A single morning dose of Adderall produced equivalent behavioral effects to those of MPH received twice-daily and behavioral effects of that single morning dose lasted throughout the school-day period. One morning dose of MPH was less effective than either 2 daily doses of MPH or 1 dose of Adderall, and seemed to wear off in the early to mid-afternoon. For some children a single morning dose of MPH maintained their behavior for an entire school day in the context of the summer treatment program. On parent ratings of evening behavior, 0.3 mg/kg of MPH at 3:30 PM was superior to 0.15 mg/kg at 3:30 PM, but there was no difference between the 2 doses of Adderall. Compared with placebo at 3:30 PM, only the 0.3 mg/kg dose of MPH caused significant improvement in parent ratings. In placebo versus Adderall comparisons, all doses, even the condition that consisted of Adderall in the morning and placebo at 3:30 PM, produced a significant change in evening behavior.

CONCLUSIONS

The results show that, at least in the context of an intensive behavioral intervention, a single morning dose of Adderall had behavioral effects throughout an entire school day period that were equivalent to standard twice-daily MPH dosing. These results indicate that Adderall may be used as a long-acting stimulant for children for whom midday dosing is a problem. Further study including dose-response comparisons, effects in regular school settings, and direct comparisons with comparable doses of MPH and d-amphetamine will help to clarify the time course and relative advantages of Adderall.

A comparison of ritalin and adderall: efficacy and time-course in children with attention-deficit/hyperactivity disorder

OBJECTIVE

Very little research has focused on the efficacy of Adderall (Shire-Richwood Inc, Florence, KY) in the treatment of children with attention-deficit/hyperactivity disorder (ADHD), and no studies have compared it with standardized doses of Ritalin (Novartis Pharmaceuticals, East Hanover, NJ). It is thought that Adderall has a longer half-life than Ritalin and might minimize the loss of efficacy that occurs 4 or 5 hours after Ritalin ingestion. We compared two doses of Ritalin and Adderall in the treatment of ADHD in children in an acute study and assessed the medications' time courses.

DESIGN

Within-subject, double-blind, placebo-controlled, crossover design lasting 6 weeks. As in our previous work, medication changes occurred on a daily basis in random order over days.

SETTING

Eight-week, weekday (9 hours daily) summer treatment program at the State University of New York at Buffalo, using an intensive behavioral treatment program including a point system and parent training.

STUDY PARTICIPANTS

Twenty-five children (21 boys and 4 girls) diagnosed as ADHD using standardized structured interview and rating scales, mean age 9.6 years, 88% Caucasian, of average intelligence, with no medical conditions that would preclude a trial of stimulant medication. Thirteen were comorbid for oppositional-defiant disorder and another 8 for conduct disorder.

INTERVENTIONS

Children received 10 mg of Ritalin, 17.5 mg of Ritalin, 7.5 mg of Adderall, 12.5 mg of Adderall, or placebo, twice a day (7:45 AM and 12:15 PM), in random order with conditions changing daily for 24 days.

OUTCOME MEASURES

Daily rates of behaviors in recreational and classroom settings, and standardized ratings from counselors, teachers, and parents, were averaged across days within condition within child and compared. Within-subject relative sizes of the medication effects were computed by taking the placebo-minus-drug mean difference divided by the placebo standard deviation for each child, and were compared hourly between first daily ingestion (7:45 AM) and 5:00 PM to assess the time course of the two drugs. Measures were taken at 12:00 PM (recess rule violations) and at 5:00 PM (parent behavior ratings) to determine whether Adderall was still effective at times when the effects of Ritalin should have worn off. Parent ratings were also made for evening behavior to assess possible rebound, and side effects ratings were obtained from parents, counselors, and teachers. Parents, counselors, and teachers also rated their perceptions of medication status and whether they recommended the continued use of the medication given that day. Finally, a clinical team made recommendations for treatment taking into account each child's individual response.

RESULTS

Both drugs were routinely superior to placebo and produced dramatic improvements in rates of negative behavior, academic productivity, and staff/parent ratings of behavior. The doses of Adderall that were assessed produced greater improvement than did the assessed doses of Ritalin, particularly the lower dose of Ritalin, on numerous but not all measures. This result suggests that the doses of Adderall used were functionally more potent than those for Ritalin. Adderall was generally superior to the low dose of Ritalin when the effects of Ritalin were wearing off at midday and late afternoon/early evening. The lower dose of Adderall produced effects comparable to those of the higher dose of Ritalin. Both drugs produced low and comparable levels of clinically significant side effects. Staff clinical recommendations for continued medication favored Adderall three to one. Almost 25% of the study participants were judged to be nonresponders by the clinical team, presumably because of their large beneficial response to the concurrent behavioral intervention and minimal incremental benefit from medication.

CONCLUSIONS

This is the first investigation to assess comparable doses of Adderall and Ritalin directly. (ABSTRACT TRU

Food diversity versus breastfeeding choice in determining anthropometric status in rural Kenyan toddlers

BACKGROUND

Prolonged breastfeeding in developing countries is routinely recommended as a valuable and cost-effective public health measure to promote early childhood growth. However, the effects of breastfeeding beyond 12 months are unclear, with some studies showing positive, and some showing negative effects. The role of complementary foods for children 1-3 years has been less studied.

METHODS

We examined feeding behaviour and illness data in relation to anthropometric status among 154 rural western Kenyan children, aged 12-36 months.

RESULTS

There was little difference in anthropometric status between partially breastfed and fully weaned children. Rather, dietary diversity (number of different foods consumed) was strongly and consistently related to anthropometric status in this age group. In addition, early complementation with starchy gruels was associated with stunting.

CONCLUSIONS

Public health efforts which focus only on prolonged breastfeeding (>12 months) in developing countries will not ensure adequate early childhood growth. Important complementary feeding recommendations that promote diet diversity, through the inclusion of a variety of foods in the diets of children in the 1-3 year age group, are needed.

Household headship and child nutrition: a case study in western Kenya

The effect of female household headship on child nutrition has been hypothesized by some to be negative, based on the assumption that mothers alone will be poorer and will have greater demands on their time and resources. On the other hand, there is some evidence in Kenya that the nutritional status of children of female heads may be better than that of children of male heads, suggesting that when women have more control over resources, more goes to the children. In Kenya, de facto female headship is common due to male labor migration. This study examines the relationship between child nutrition and de facto female vs male household headship in western Kenya through the examination of family income and decision making patterns. Women in male-headed households had greater financial responsibility for household maintenance. Female heads assumed more farming responsibilities and had higher remittances from husbands. Husbands of female heads purchased food and other goods in the city for use by the household. Male headed households produced more food crops and used a larger proportion of them for home consumption. In this study, children of female heads consumed a greater variety of foods. Despite a greater prevalence of stunting, there was a lower prevalence of low weight for age among children of female heads. However, in statistical analyses, headship did not relate significantly to nutritional intake or status. In attempting to understand the possible factors influencing the relationship between headship and nutritional status, we found trade-offs in the ways families were coping, which appeared to balance some of the negative and positive effects of each situation.