A breeding goal for South African Holstein Friesians in terms of economic weights in percentage units

In South Africa the exact breeding goal for Holstein Friesians still needs to be determined. This means that the traits, which should be most important in selection have to be identified. One method to identify these traits could be to calculate economic weights for production and functional traits. Economic weights calculated in absolute units cannot be compared because some traits are measured in different units. The objective of this study was therefore the calculation of economic weights for production and functional traits, in percentage units, to make a comparison between traits possible. The production traits were milk, butterfat, protein and lactose yield and the functional traits included survival rate, feed efficiency, live weight and calving interval. The study used a simulation model to calculate economic weights. This model included three production enterprises classified according to the production level of the herds. The results show that for all three the production enterprises milk yield is potentially the most important trait to improve in selection, with the second trait being feed efficiency followed by live weight. The results were confirmed by constructing a selection index, including milk yield and live weight, showing that economic improvement with a selection index is about 25% more efficient than direct selection for milk yield alone.In Suid-Afrika is die presiese teeldoelwit vir Holstein Friese nog nie bepaal nie. Dit beteken dat die eienskappe wat die belangrikste behoort te wees in seleksie nog geidentifiseer moet word. Berekening van ekonomiese gewigte vir produksie en funksionele eienskappe is een manier om hierdie eienskappe te identifiseer. Met ekonomiese gewigte in absolute eenhede is 'n vergelyking tussen die eienskappe nie moontlik nie, omdat eienskappe gemeet word in verskillende eenhede. Die doelwit van hierdie studie was die berekening van ekonomiese gewigte in persentasie eenhede om 'n vergelyking van die eienskappe moontlik te maak. Die produksie-eienskappe in die studie was melk-, bottervet-, proteien- en laktose opbrengs en die funksionele eienskappe het oorlewingstempo, voerdoeltreffendheid, liggaamsmassa en kalfinterval ingesluit. Die studie het 'n simulasiemodel gebruik om ekonomiese gewigte te bereken met die insluiting van drie produksiesisteme wat geklassifiseer is volgens die produksievlak van die kudde. Die resultate toon dat vir al drie die produksie-sisteme melkopbrengs potensieel die belangrikste eienskap is om te verbeter in seleksie, met voerdoeltreffendheid die tweede belangrikste eienskap gevolg deur liggaamsmassa. Om die resultate te staaf is 'n seleksie-indeks bereken, wat melkopbrengs en liggaamsmassa insluit en getoon het dat ekonomiese vordering ongeveer 25% meer effektief is met indeks-seleksie as seleksie slegs vir melkopbrengs.https://www.sasas.co.za/resources/sa-journal-animal-sciencehj2020Genetic

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Breeding phenology and meteorological conditions affect carer provisioning rates and group-level coordination in cooperative chestnut-crowned babblers

Recent theoretical and empirical work suggests that coordinating offspring provisioning plays a significant role in stabilizing cooperative care systems, with benefits to developing young. However, a warming and increasingly extreme climate might be expected to make contributions to, and so coordination of, care more challenging, particularly in cooperative breeding systems comprising multiple carers of varying age and pairwise relatedness. Here we investigated the interplay between breeding phenology, meteorological conditions and carer number on the individual rates and group-level coordination of nestling care in the cooperatively breeding chestnut-crowned babbler (Pomatostomus ruficeps) in outback south-eastern Australia. From 3 months since the last meaningful rain event, dominant male breeders and—to a lesser extent—related helpers showed reductions in their provisioning rates and increases in their day-to-day variation. Further, on days with high mean wind speed, dominant males contributed less and helpers were less likely to visit the nest on such days. Helpers also showed reduced visitation rates on days with high mean temperature. Provisioning rates were independent of the number of carers, and increasing numbers of carers failed to mitigate the detrimental effects of challenging environment on patterns of provisioning. Those helpers that were unrelated to broods often failed to help on a given day and tended to help at a low rate when they did contribute, with socio-environmental predictors having limited explanatory power. Given the marked variation in individual contributions to offspring care and the variable explanatory power of the socio-environmental predictors tested, babblers unsurprisingly had low levels of nest visitation synchrony. Large groups visited the nest more asynchronously on days of high mean temperature, suggesting that meteorological impacts on individual provisioning have consequences for group-level coordination. Our study has implications for the consequences of climate change on patterns of provisioning, the minimal role of group size in buffering against these challenges and the stabilization of cooperative care

Neonatal communication intervention in South Africa : training needs and future strategies

Advances in neonatal medicine during the past 35 years have led to the survival of more preterm infants than ever before. The focus of the management of preterm infants has consequently shifted from survival to providing for developmental needs, from as early as possible. The increased prevalence of at-risk infants born in South Africa necessitates the appropriate implementation of neonatal communication intervention (NCI) programmes. Since mothers do not always return to health care facilities for follow-up services but are available during the neonatal period, the speech-language therapist should assist them with feeding development, mother-infant attachment and reciprocal communication interaction. The paediatric audiologist should reduce noise levels in the neonatal intensive care unit (NICU) to protect neonatal hearing, conduct a hearing screening test within the first month of life and train parents to create the appropriate auditory environment that will facilitate listening and language development. Audiologists and speech-language therapists need to be fully competent and well-trained in providing NCI, so that their services in the unique multicultural and multilingual South African context can become increasingly effective. The aim of the study was to describe the self-perceived skills and needs of South African audiologists and speech-language therapists regarding NCI. A triangulation mixed model research design, which entails a combination of quantitative and qualitative research techniques, was used. A descriptive survey was employed to describe the self-perceived skills and needs in NCI of 73 participating South African audiologists and/or speech-language therapists. The results of this study indicated that participants experienced the greatest difficulty with and the least confidence in feeding intervention. The participants perceived their skills in communication intervention, neonatal hearing intervention and general collaborative tasks in NCI to be better than their skills in feeding intervention. Some of the participants did not recognise their vital role in kangaroo mother care (KMC), although it is the ideal entry point for the implementation of NCI programmes. The participants identified needs in terms of knowledge and skills regarding feeding intervention, developmental care and KMC. The majority indicated that they perceived their level of practical training as lacking, and that any training in NCI should include practical aspects. It was also found that the participants’ current profession and their professional qualification significantly influenced their reported skills in feeding, communication and neonatal hearing intervention. The more recently qualified participants and those with more clinical experience also reported greater confidence in and less difficulty with feeding and communication intervention, as well as with general neonatal intervention tasks. The findings of this study emphasise the need for audiologists and speech-language therapists to use KMC as the entry point for NCI services. Training in early communication intervention (ECI) and NCI at an undergraduate level should be expanded to include more practical activities, and may need to be standardised across tertiary institutions in South Africa. Professionals working in neonatal settings should also participate in professional development courses that include practical application of learnt skills. Through these activities, NCI services to the paediatric population may reach the necessary standard of best practice.Dissertation (MComm Path)--University of Pretoria, 2015.tm2015Speech-Language Pathology and AudiologyMComm PathUnrestricte

Economic weights for Holstein Friesian traits in South Africa

In this study economic weights for production and functional traits of the Holstein Friesians in South Africa were calculated using a simulation model. The production traits were milk, butterfat, protein and lactose yield and the functional traits included feed efficiency, survival rate, calving interval and live weight. The simulation model was developed for three production systems and made use of two South African milk price systems to calculate the economic weights. In both price systems the feed efficiency had the largest economic weight, followed by the four production traits. The economic weights of the other functional traits were much smaller than the economic weights of the production traits.https://www.sasas.co.za/resources/sa-journal-animal-scienceam2020Genetic

Phenotypic flexibility of metabolic rate and evaporative water loss does not vary across a climatic gradient in an Afrotropical passerine bird

Small birds inhabiting northern temperate and boreal latitudes typically increase metabolic rates during cold winters or acclimation to low air temperatures (Taccl). Recent studies suggest considerable variation in patterns of seasonal metabolic acclimatization in birds from subtropical and tropical regions with milder winters, but there remains a dearth of acclimation studies investigating metabolic flexibility among lower-latitude birds. We used short-term thermal acclimation experiments to investigate phenotypic flexibility in basal metabolic rate (BMR), thermoneutral evaporative water loss (EWL) and summit metabolism (Msum) in three populations of white-browed sparrow-weavers (Plocepasser mahali) along a climatic and aridity gradient. We allocated individuals to one of three Taccl treatments (5, 20 and 35°C; n=11 per population per Taccl) for 28 days, and measured post-acclimation BMR, EWL and Msum using flow-through respirometry. Our data reveal the expected pattern of lower BMR and EWL (∼12% and 25% lower, respectively) in birds at Taccl=35°C compared with cooler Taccl treatments, as observed in previous acclimation studies on subtropical birds. We found no variation in the reaction norms of BMR and EWL among populations in response to acclimation, suggesting previously documented differences in seasonal BMR acclimatization are the result of phenotypic flexibility. In contrast to higher-latitude species,Msum did not significantly vary in response to thermal acclimation. These findings support the idea that factors other than enhancing cold tolerance may be driving patterns of metabolic variation in subtropical birds.The DST-NRF Centre of Excellence at the FitzPatrick Institute and the National Research Foundation of South Africa.http://jeb.biologists.org2021-04-09am2020Zoology and Entomolog

The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

Background: The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications. Methods: ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery. Results: The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784. Conclusions: This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance. © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.Medical Research Council of South Africa gran

Maternal and neonatal outcomes after caesarean delivery in the African Surgical Outcomes Study: a 7-day prospective observational cohort study.

BACKGROUND: Maternal and neonatal mortality is high in Africa, but few large, prospective studies have been done to investigate the risk factors associated with these poor maternal and neonatal outcomes. METHODS: A 7-day, international, prospective, observational cohort study was done in patients having caesarean delivery in 183 hospitals across 22 countries in Africa. The inclusion criteria were all consecutive patients (aged ≥18 years) admitted to participating centres having elective and non-elective caesarean delivery during the 7-day study cohort period. To ensure a representative sample, each hospital had to provide data for 90% of the eligible patients during the recruitment week. The primary outcome was in-hospital maternal mortality and complications, which were assessed by local investigators. The study was registered on the South African National Health Research Database, number KZ_2015RP7_22, and on ClinicalTrials.gov, number NCT03044899. FINDINGS: Between February, 2016, and May, 2016, 3792 patients were recruited from hospitals across Africa. 3685 were included in the postoperative complications analysis (107 missing data) and 3684 were included in the maternal mortality analysis (108 missing data). These hospitals had a combined number of specialist surgeons, obstetricians, and anaesthetists totalling 0·7 per 100 000 population (IQR 0·2-2·0). Maternal mortality was 20 (0·5%) of 3684 patients (95% CI 0·3-0·8). Complications occurred in 633 (17·4%) of 3636 mothers (16·2-18·6), which were predominantly severe intraoperative and postoperative bleeding (136 [3·8%] of 3612 mothers). Maternal mortality was independently associated with a preoperative presentation of placenta praevia, placental abruption, ruptured uterus, antepartum haemorrhage (odds ratio 4·47 [95% CI 1·46-13·65]), and perioperative severe obstetric haemorrhage (5·87 [1·99-17·34]) or anaesthesia complications (11·47 (1·20-109·20]). Neonatal mortality was 153 (4·4%) of 3506 infants (95% CI 3·7-5·0). INTERPRETATION: Maternal mortality after caesarean delivery in Africa is 50 times higher than that of high-income countries and is driven by peripartum haemorrhage and anaesthesia complications. Neonatal mortality is double the global average. Early identification and appropriate management of mothers at risk of peripartum haemorrhage might improve maternal and neonatal outcomes in Africa. FUNDING: Medical Research Council of South Africa.Medical Research Council of South Africa