Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Utilisation of treated straw from newly-developed PadiU PUTRA-1 rice variety as feed supplement for sustainable goat production

The persistent challenges of meeting the global population's demand for animal protein in the ruminant industry, centred on feed to boost production. To bridge the niche areas for the realisation of food security, the availability of feed that is cheap, noncompetitive, qualitative, and sustainable is required. Agricultural waste, such as rice straw that is illicitly disposed of, causing health impairment and global environmental nuisance through burning could be improved by biological additive and used as ruminant feed. However, biological additives have been reported to improve straw quality through ensiling and possibly animal performance. As a result, the objective of the study refers to the use of enriched straw from a newly developed rice variety as a feed supplement for a sustainable goat production. This thesis comprised of three research chapters. The aim of the first experiment was to examine the efficacy of biological additives on nutrient profiles, ensile quality, in vitro rumen fermentation in different varieties of treated rice straw; ML4, ML10, ML21, ML24, MR219 and PadiU Putra-1 were ensiled with water (Control), enzyme (E) and combination of bacteria and enzyme (BE) in a complete randomise design (CRD) experiment. The rice straw varieties, obtained from the paddy research farm were chopped to about 2-3 cm, treated according to the above treatments to attain 70% moisture content, compressed in a 1 L jar and ensiled for 30 days. Results showed that treatment with the combination of bacteria and enzyme had lower neutral detergent fiber (42.31%) and lower acid detergent fiber (21.08%) for PadiU Putra-1 than other treatments (enzyme and control) and varieties. For the ensiled extract, the lowest pH, NH3, butyric acid and propionic acid were obtained in BE treatment in most of the rice straw varieties. In addition, straw treated with BE had significantly higher lactic acid content, in vitro gas production kinetics, digestibility, and rumen fermentation compared to the enzyme and control. This study revealed that a combination of bacterial and enzyme treatment effectively improved the quality of treated rice straw, with the PadiU Putra-1 variety being the most outstanding. Selection of the appropriate biological treatment and variety of rice straw is important to improve straw quality. However, the treated rice straw needs further evaluation for its in vivo efficacy. The second experiment investigated the effects of PadiU Putra-1 treated rice straw with biological additives on growth performance, nutrient digestibility, rumen fermentation, microbial population, and relative expressions of ruminal MCT1 and growth hormone genes in goats. Twenty-four male crossbred Boer goats were randomly assigned to the following diets: (i) Control (untreated straw); (ii) Enzyme treated straw; and (iii) BE, enzyme plus lactic acid bacteria treated straw. Each diet, in the form of total mixed ration consisted of 50% treated rice straw and 50% concentrate was fed at 3.5% DM body weight of the experimental animals for 14 weeks. The results showed that average daily gain (ADG) of goats was 13% and 26%, respectively, higher in enzyme and BE treatment than the control (P<0.01). Feed efficiency (gain:feed) was also enhanced by 8% and 23% in Enzyme and BE treatment diets relative to control. Goats fed treated straws had higher nutrient digestibility leading to higher digestible nutrient intake (P<0.001). Dietary treatments had no effect on rumen fermentation except propionate concentrations which were higher in the treated rice straw groups leading to lower acetate to propionate ratio (P<0.01). Goats fed treated rice straw had higher cellulolytic bacteria but lower protozoa and methanogens which resulted in lower methane concentration; greater expression of ruminal MCT1 and hepatic GHR, IGF-1 genes (P<0.01) indicating better rumen absorption, growth process and nutrient metabolism. The third research chapter examines the influence of biologically treated rice straw on blood profiles (haematology and biochemistry), non-carcass, carcass characteristics and meat quality in goats. The blood samples from each animal were taken from the jugular vein using vacuum EDTA and serum tube for haematological and biochemical blood profile analysis ascertain the non-detrimental effect of the diet while the meat quality analysis was performed after the slaughtering and the ageing days. The blood profile results indicated dietary treatment had no detrimental effect on the haematological and biochemical profiles, but the days of sampling had significant effect. On the carcass trait, enzyme treatment increased slaughter weight, hot carcass, and cold carcass by 4%, 6%, and 6%, respectively, compared to the control, whereas BE treatment increased the above parameters by 9%, 13%, and 15%, respectively (P<0.05). In addition, the dietary treatment improved the chilling loss and dressing percentages, but had no effect on the non-carcass and primal cuts. Dietary treatment influenced the cooking loss percentage and shear force, whereas other physicochemical meat qualities were unaffected but had a post-mortem ageing effect

Effects of tree leaf forage supplementation on rumen fermentation and microbial profile of goats

Increase in the cost of livestock production with the use of conventional feed is distressful, threatening the food security and livestock sustenance especially ruminant. Alternative to this is to diversify and quest for other source of feed such as forages which are inexpensive, high proximity and high nutritive value for animal optimum utilization. Hence, the purpose of the present study. In the first experiment, evaluation of nutritive and anti-nutritive factor of three selected tree forages (Kleinhovia hospita, Leucaena leucocephala and Gliricidia sepium) and their effect on the in vitro rumen fermentation were investigated. The proximate analysis was determined by AOAC procedure, in vitro cumulative gas production using Ørskov and McDonald model, metabolizable energy determined by Menke and Steingass equation method and rumen fermentation by gas chromatography. The crude protein (CP) of the forages (19%, 23.3% and 20.8% respectively) were more than the 12% CP requirement of ruminant. The NDF and ADF which to some extent dictate the feed intake and the digestibility respectively was found to be lower in KH compared to LL and GS. The lower value is an indication of higher feed intake and digestibility. In the in vitro study, the net gas production (NGP), in vitro dry matter digestibility and metabolizable energy was also high in KH than LL and GS. Furthermore, the result from the in vitro rumen fermentation indicated that the total volatile fatty acid (TVFA) was significantly different (P0.05) at 12 h postprandial but the propionic acid concentration were significantly different among the dietary treatments with KHLL having the highest concentration followed by KH, LL and control. In the butyric acid concentration at 12 h postprandial, the control, KH and LL were similar and significantly different (P<0.05) from KHLL which recorded the lowest butyric acid concentration and this was a confirmation of the efficient utilization of the dietary energy. In the concentration of acetic acid, the level was noted to increase until 4 h postprandial before gradual decline with the KHLL recorded to be higher (P<0.05) than the rest. Similarly, the NH3 concentration of KHLL is significantly different (P<0.05) from other diets which were similar. From the in vivo microbial population profile result, the total bacteria were noted to be at the peak of their population at 4 h postprandial before gradual decline in all treatment diets. At 12 h postprandial, the total protozoa and methanogens were found decreasing with sampling time and the forage inclusion diets (KHLL, KH and LL) were significantly lower (P<0.05) than the control. The number of cellulolytic bacteria R. albus, R. flavefaciens and Fibrobacter succinogenes were more in the forage inclusion diet than the control at 4 h postprandial. Based on the outcome of the present study, it can be concluded that the KHLL inclusion diet could be efficiently used in goat diet without compromising the nutrient potential by reducing the methanogen and protozoa numbers, enhancing propionic acid, acetic acid and nutrient utilization. In addition, acetate is essential in the formation of milk fat and propionate aid the synthesis lactose (milk sugar) as well as increase milk yields in dairy animals

New insights in improving sustainability in meat production: opportunities and challenges

Treating livestock as senseless production machines has led to rampant depletion of natural resources, enhanced greenhouse gas emissions, gross animal welfare violations, and other ethical issues. It has essentially instigated constant scrutiny of conventional meat production by various experts and scientists. Sustainably in the meat sector is a big challenge which requires a multifaced and holistic approach. Novel tools like digitalization of the farming system and livestock market, precision livestock farming, application of remote sensing and artificial intelligence to manage production and environmental impact/GHG emission, can help in attaining sustainability in this sector. Further, improving nutrient use efficiency and recycling in feed and animal production through integration with agroecology and industrial ecology, improving individual animal and herd health by ensuring proper biosecurity measures and selective breeding, and welfare by mitigating animal stress during production are also key elements in achieving sustainability in meat production. In addition, sustainability bears a direct relationship with various social dimensions of meat production efficiency such as non-market attributes, balance between demand and consumption, market and policy failures. The present review critically examines the various aspects that significantly impact the efficiency and sustainability of meat production

Improving animal welfare status and meat quality through assessment of stress biomarkers: a critical review

Stress induces various physiological and biochemical alterations in the animal body, which are used to assess the stress status of animals. Blood profiles, serum hormones, enzymes, and physiological conditions such as body temperature, heart, and breathing rate of animals are the most commonly used stress biomarkers in the livestock sector. Previous exposure, genetics, stress adaptation, intensity, duration, and rearing practices result in wide intra- and inter-animal variations in the expression of various stress biomarkers. The use of meat proteomics by adequately analyzing the expression of various muscle proteins such as heat shock proteins (HSPs), acute phase proteins (APPs), texture, and tenderness biomarkers help predict meat quality and stress in animals before slaughter. Thus, there is a need to identify non-invasive, rapid, and accurate stress biomarkers that can objectively assess stress in animals. The present manuscript critically reviews various aspects of stress biomarkers in animals and their application in mitigating preslaughter stress in meat production

Rumen microbial community and nitrogen metabolism in goats fed blend of palm oil and canola oil

This study assessed the influence of dietary blend of 20% palm oil and 80% canola oil on the population of rumen microbiota and nitrogen economy in goats. Twenty-four Boer bucks (4–5 months old; initial BW, 20.54 ± 0.474 kg) were randomly allotted to diets containing on a dry matter basis, 0, 4 or 8% oil blend, fed daily for 100 days and slaughtered. The rumen microbiota was examined by quantitative real-time polymerase chain reaction (PCR) using the 16S rRNA gene. The population of total protozoa and methanogens was lower (p  0.05) on microbial N yield, microbial protein synthesis, efficiency of microbial protein synthesis and the intake, retention and excretion of N. Dietary supplementation of blend of palm oil and canola oil altered rumen microbial profile but did not affect nitrogen metabolism in goats

Technological interventions in improving the functionality of proteins during processing of meat analogs

Meat analogs have opened a new horizon of opportunities for developing a sustainable alternative for meat and meat products. Proteins are an integral part of meat analogs and their functionalities have been extensively studied to mimic meat-like appearance and texture. Proteins have a vital role in imparting texture, nutritive value, and organoleptic attributes to meat analogs. Processing of suitable proteins from vegetable, mycoproteins, algal, and single-cell protein sources remains a challenge and several technological interventions ranging from the isolation of proteins to the processing of products are required. The present paper reviews and discusses in detail various proteins (soy proteins, wheat gluten, zein, algal proteins, mycoproteins, pulses, potato, oilseeds, pseudo-cereals, and grass) and their suitability for meat analog production. The review also discusses other associated aspects such as processing interventions that can be adapted to improve the functional and textural attributes of proteins in the processing of meat analogs (extrusion, spinning, Couette shear cell, additive manufacturing/3D printing, and freeze structuring)

Marker-assisted introgression of multiple resistance genes confers broad spectrum resistance against bacterial leaf blight and blast diseases in Putra-1 rice variety

Bacterial leaf blight caused by Xanthomonas oryzae pv oryzae (Xoo) and blast caused by Magnaporthe oryzae are major diseases responsible for significant yield loss in rice production across all rice growing regions. Host plant resistance has been advocated as a sustainable means of guarding against the diseases. This experiment was conducted with the aim to introgress multiple resistance genes against bacterial leaf blight and blast diseases through marker-assisted backcross breeding. Two dominant (Xa4 and Xa21) and two recessive (xa5 and xa13) Xoo resistance genes were introgressed into a high yielding Malaysian rice variety Putra-1 with genetic background of three blast resistance (Piz, Pi2 and Pi9) genes. Eight polymorphic tightly linked functional and SSR markers were used for foreground selection of target genes. Seventy nine polymorphic SSR markers were used in background selection. The plants were challenged at initial stage of breeding and challenged again at BC2F2 with the most virulent Malaysian pathotypes of Xoo (P7.7) and Magnaporthe oryzae (P7.2) to test their resistance. Results obtained from foreground marker segregation analysis at BC1F1 and BC2F1 showed that the marker polymorphism both fitted into the Mendel’s single gene segregation ratio of 1:1 for both Xoo and blast resistance. At BC2F2, results indicated that foreground marker polymorphism fitted into the expected Mendelian ratio of 1:2:1 for blast resistance only. Marker-assisted background selection revealed high percentage of recurrent parent genome recovery (95.9%). It was concluded that the inheritance of blast resistance in the introgressed lines was mainly due to single gene action while the inheritance of Xoo resistance was substantially due to single nuclear gene action. The incorporation of four bacterial leaf blight and three blast resistance genes (Xa4 + xa5 + xa13 + Xa21; Pi9 + Pi2 + Piz) in the newly developed lines would provide for broad spectrum and durable resistance against the two major diseases studied