BackgroundWhile there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria.MethodsIn this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced.ResultsGBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes.ConclusionsGBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future.

A meta-analysis of the potential effect of forage provision on growth performance and rumen fermentation of dairy calves was conducted using published data from the literature (1998-2016). Meta-regression was used to evaluate the effects of different forage levels, forage sources, forage offering methods, physical forms of starter, and grain sources on the heterogeneity of the results. We considered 27 studies that reported the effects of forage provision to dairy calves. Estimated effect sizes of forage were calculated on starter feed intake, average daily gain (ADG), feed efficiency (FE), body weight (BW), and rumen fermentation parameters. Intake of starter feed, ADG, BW, ruminal pH, and rumen molar proportion of acetate increased when supplementing forage but FE decreased. Heterogeneity (the amount of variation among studies) was significant for intake of starter feed, ADG, FE, final BW, and rumen fermentation parameters. Improving overall starter feed intake was greater in calves offered alfalfa hay compared with those offered other types of forages. During the milk feeding and overall periods, improving ADG was greater for calves fed a high level of forage (>10% in dry matter) compared with those fed a low level of forage (≤10% in dry matter) diets. The advantages reported in weight gain at a high level of forage could be due to increased gut fill. Improving overall ADG was lower for calves offered forages with textured starter feed compared with ground starter feed. The meta-regression analysis revealed that changes associated with forage provision affect FE differently for various forage sources and forage offering methods during the milk-feeding period. Forage sources also modulated the effect of feeding forage on ruminal pH during the milk-feeding period. In conclusion, forage has the potential to affect starter feed intake and performance of dairy calves, but its effects depend on source, level, and method of forage feeding and physical form of starter feed independently of grain sources included in the starter feed.

Introducing forage in the young calf diet during the milk-feeding period stimulates rumen development. It was hypothesized that performance in dairy calves would depend on forage provision and starter physical form such that the textured starter (TS) feed with corn silage (CS) supplementation would benefit calf performance. This study evaluates the effects of the physical form of starter diets and CS supplementation on performance, rumen fermentation characteristics, and structural growth of dairy calves. Forty-eight 3-d-old Holstein dairy calves with a mean starting BW of 42.1 kg (SD 2.4) were used in a 2 × 2 factorial arrangement with the factors dietary CS level (0 or 15% on DM basis) and physical form of starter (mashed vs. textured). Individually housed calves were randomly assigned ( = 12 calves per treatment: 6 males and 6 females) to 4 treatments: 1) a mashed starter (MS) feed with no CS (MS-NCS), 2) a MS feed with CS (MS-CS), 3) a TS feed with no CS (TS-NCS), and 4) a TS feed with CS (TS-CS). The calves had ad libitum access to water and starter throughout the study. All calves were weaned on d 56 of age and remained in the study until d 66. The interaction of the physical form of the starter and CS provision was significant ( < 0.01) for the starter intake, with the greatest intake for TS-CS treatment during the preweaning and overall periods. Regardless of the physical form of starter, starter intake, ADG, weaning BW, final BW, ruminal pH, the molar proportion of acetate, and the acetate-to-propionate ratio were greater ( < 0.01) for CS-supplemented calves compared with unsupplemented calves. No interaction ( > 0.05) was detected between the physical form of starter and CS provision with respect to the rumen fermentation parameters and body measurements. Total rumen VFA concentration and the molar proportion of propionate were greater ( < 0.01) in calves fed TS compared with MS-fed calves. In conclusion, independent of the physical form of starter, inclusion of 15% CS in starter diets improves the performance of dairy calves.

Introducing forage in dairy calf diets during the preweaning period stimulates development of rumen capacity and function and gut wall integrity. It was hypothesized that calves fed alfalfa hay (AH) at greater levels (up to 25% of DM) would result in an increase in starter diet intake and growth performance. The objective of this study was to determine the effects of increasing levels of supplemental AH on growth performance, rumen fermentation, blood metabolites, and feeding behavior in intact male dairy calves. For this purpose, 45 Holstein male calves (3 d of age and 41 ± 2.5 kg of BW) were randomly assigned to 1 of the following 3 starter diets differing in their forage level: 1) diet without AH (control), 2) diet with 12.5% AH on a DM basis, and 3) diet with 25% AH on a DM basis. Supplementation of AH in the starter diets linearly increased total DMI and ADG during the postweaning ( < 0.01) and overall ( = 0.02) periods. Alfalfa hay supplementation linearly increased ( < 0.01) ruminal pH on d 35 and 70 of the study. The concentrations of total VFA ( = 0.85), acetate ( = 0.74), propionate ( = 0.93), and butyrate ( = 0.91) were not affected by treatments. Furthermore, forage supplementation tended (linearly, = 0.08) to increase the acetate to propionate ratio compared with the control calves. Blood β-hydroxybutyrate (BHBA) concentrations in the control calves were less ( = 0.03) than in the AH-fed calves on d 70 of the study. Among all the measured variables of skeletal growth, supplementation of AH in the starter diets linearly increased heart girth ( = 0.05) and abdominal girth ( < 0.01) on d 70 of the study. These results indicate that the feed intake, feeding behavior, rumen fermentation parameters, and blood BHBA concentration may be affected by rations differing in AH level so that providing calves with 25% AH can improve calf performance.

The objective of this study was to investigate the effects of grain sources and forage provision on growth performance, blood metabolites, and feeding behaviors of dairy calves. Sixty 3-d-old Holstein dairy calves (42.2 ± 2.5 kg of body weight) were used in a 2 × 3 factorial arrangement with the factors being grain sources (barley and corn) and forage provision (no forage, alfalfa hay, and corn silage). Individually housed calves were randomly assigned (n = 10 calves per treatment: 5 males and 5 females) to 6 treatments: (1) barley grain (BG) without forage supplement, (2) BG with alfalfa hay (AH) supplementation, (3) BG with corn silage (CS) supplementation, (4) corn grain (CG) without forage supplement, (5) CG with AH supplementation, and (6) CG with CS supplementation. All calves had ad libitum access to water and starter feed throughout the experiment. All calves were weaned on d 49 and remained in the study until d 63. Starter feed intake and average daily gain (ADG) was greater for calves fed barley than those fed corn during the preweaning and overall periods. Calves supplemented with CS had greater final body weight and postweaning as well as overall starter feed intake than AH and non-forage-supplemented calves. During the preweaning and overall periods, feeding of CS was found to increase ADG compared with feeding AH and nonforage diets. However, feed efficiency was not affected by dietary treatments. Calves supplemented with CS spent more time ruminating compared with AH and control groups; nonnutritive oral behaviors were the greatest in non-forage-supplemented calves. Regardless of the grain sources, the rumen pH value was greater for AH calves compared with CS and non-forage-supplemented calves. Blood concentration of BHB was greater for CS-supplemented calves compared with AH and non-forage-supplemented calves. Furthermore, body length and heart girth were greater for calves fed barley compared with those fed corn, and also in forage-supplemented calves compared with non-forage-supplemented calves. These results showed no interactions between grain sources and forage provision on calf performance; however, the inclusion of CS and barley in starter diets could enhance the growth performance of Holstein calves during the transition from liquid to solid feed.