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Agriculture plays a central role in achieving most Sustainable Development Goals (SDGs). Sustainable intensification (SI) of agriculture has been proposed as a promising concept for safeguarding global food security, while simultaneously protecting the environment and promoting good quality of life. However, SI often leads to context-specific sustainability trade-offs. Operationalising SI thus needs to be supported by transparent sustainability assessments. In this article, we propose a general systematic approach to developing context-specific frameworks for integrated sustainability assessment of agricultural intensity change. Firstly, we specify a comprehensive system representation for analysing how changes in agricultural intensity lead to a multitude of sustainability outcomes affecting different societal groups across geographical scales. We then introduce a procedure for identifying the attributes that are relevant for assessment within particular contexts, and respective indicator metrics. Finally, we illustrate the proposed approach by developing an assessment framework for evaluating a wide range of intensification pathways in Europe. The application of the approach revealed processes and effects that are relevant for the European context but are rarely considered in SI assessments. These include farmers’ health, workers’ living conditions, cultural heritage and sense of place of rural communities, animal welfare, impacts on sectors not directly related to agriculture (e.g., tourism), shrinking and ageing of rural population and consumers’ health. The proposed approach addresses important gaps in SI assessments, and thus represents an important step forward in defining transparent procedures for sustainability assessments that can stimulate an informed debate about the operationalisation of SI and its contribution towards achieving SDGs., Environmental Science & Policy, 137, ISSN:1462-9011, ISSN:1873-6416

In this study, the incorporation of leek in wheat bread was explored. Green leek leaves were dried with two techniques to obtain leek powder after milling. The air-dried and freeze-dried powders were incorporated into wheat flour at five substitution levels (0, 0.5, 1, 1.5 and 2 g/100 g). The impact of leek powder on dough rheology, bread quality, sensory evaluation and mould-free shelf-life was investigated. Leek powder negatively impacted the mixing properties and significantly changed the viscoelastic properties of the wheat flour dough. At low levels, the dough was strengthened whereas at higher levels both dough resistance as extensibility decreased. Bread quality was also affected, resulting in lower bread volume and coarser crumb structure. The negative impact on dough and bread properties was more pronounced for freeze-dried powder. The result of the sensory study showed that wheat flour could be fortified by 1 g/100 g of leek powder without adverse effect on the consumer acceptability. Finally, the addition of leek powder did not impact the mould-free shelf-life of wheat bread.

The main objectives of this study were to investigate the antifungal activity of thyme essential oil (Thymus zygis) in-vitro and to validate its activity in par-baked wheat and sourdough bread (in-vivo) using the fungal strains Aspergillus niger and Penicillium paneum. The impact of thyme oil was evaluated in-vitro with the macro-dilution method with modified pH (4.8, 5.0, 5.5 & 6.0), aw (0.95 & 0.97) and temperature (22 & 30 °C) to mimic the conditions of wheat and sourdough par-baked bread stored at room temperature. Furthermore, the oil was applied in par-baked bread (0, 15 and 30 g sourdough/100 g dough). Challenge and shelf-life tests were performed to investigate the biopreservative potential of thyme oil in par-baked wheat and sourdough bread. Despite the promising in-vitro potential of thyme oil, no clear shelf-life extension was observed for par-baked bread which could be attributed to the oil. More research on food applications of essential oils is necessary to give the abundance of in-vitro studies industrial relevance. The use of sourdough, on the contrary, resulted in much more promising shelf-life extending properties. In both in-vitro as in-vivo assays, pH and aw showed no significant effect on fungal growth.

The main objective of this study was the investigation of different environmental growth conditions on the growth of chalk yeasts, Hyphopichia burtonii (HB), Wickerhamomyces anomalus (WA) and Saccharomycopsis fibuligera (SF). Through multiple methods, including radial growth, biocontrol assay, growth/no-growth modelling and a bread challenge test, the influence of pH (4.5–6.5), temperature (22–30 °C), propionic acid (0–0.3%) and presence of other spoilage fungi was assessed. This study showed that pH and temperature does not play a major role on the growth of HB, WA and SF. Only WA shows optimal growth at pH 4.5 and 30 °C on MEA. The likeliness of growth is the following: HB > SF > WA, except from WA at pH 4.5/30 °C. Biocontrol activity was observed against Aspergillus niger and Penicillium paneum in the presence of high concentrations of HB at 30 °C. Furthermore, this study showed that HB is most sensitive to propionic acid (PA), followed by SF and WA. The effectiveness of PA was also shown through bread challenge tests. The following order of sensitivity against PA was observed: HB > SF > WA. Breads inoculated with WA had a shorter shelf-life (2–3 days less).

Sourdough is a very interesting natural preservation system to prolong mould free shelf-life of bread. Numerous studies have reported that the antifungal activity of sourdough is mainly correlated with the presence of lactic (LA) and acetic acid (AA), but very few information is available on the effect of undissociated acid concentrations in the aqueous phase of bread (C-HA; mmole/L). This study was conducted to provide additional information about the mode of action of the acids in sourdough bread, enabling a better shelf-life prediction. This study was divided into two parts. In part 1, three industrial biological sourdoughs were characterized (dough yield, pH, a(w), fermentation quotient, microbiota). During 7 weeks, a shelf-life test with natural flora was conducted with daily checks of visible mould growth (21 degrees C). In part 2, the effect of the acids present in the antifungal active sourdough breads was validated in chemically acidified wheat breads. Complete growth inhibition was observed in full-baked sourdough bread (30 g/100 g dough) containing Lactobacillus sanfranciscensis and Saccharomyces cerevisiae as dominant sourdough micro-organisms, whereas in control bread the shelf-life was limited to 4.4-9.2 days. These full-baked sourdough breads contained 36 mmole undissociated LA/L and 220 mmole undissociated AA/L. The data were used to make General Linear Regression models for shelf-life prediction and resulted in a fit of R-2 = 0.79 when expressing the shelf-life in function of C-HA,C- LA and C-HA,C-AA. In acidified breads, the role of lactic acid was not significant and only impacted shelf-life indirectly through acidification. No difference between antifungal activity of sourdough breads and chemically acidified bread with comparable C-HA,C- AA concentrations was observed. Shelf-life increased when 150-200 mmole undissociated AA/L aqueous phase in bread was present. To conclude, this study showed the importance of the undissociated acid fraction of acetic acid in relation to bread shelf-life, together with bread pH and moisture content.

The main objectives were to investigate the antifungal effect of lactic (LA) and acetic acid (AA) and the fermentation quotient (FQ, mol/L ratio of LA over AA) towards Penicillium paneum and Aspergillus niger through growth/no-growth modelling of in-vitro data and to validate its effect in chemically acidified bread by performing challenge tests. Results have shown that AA has strong antifungal activity towards both bread moulds, albeit that P. paneum is ten times more resistant compared to A. niger. Complete growth inhibition of A. niger on chemically acidified bread was observed during 35 days at 21 °C for concentrations of AA ≥ 33 mmol/kg dough or ≥165 mmol undissociated AA/L water phase in bread. Whereas for A. niger the FQ must be close to zero and the concentration of AA in bread 33 mmol/kg dough to achieve complete growth inhibition, very high concentrations of AA and LA were needed to prevent growth of P. paneum (>100 mmol/kg dough). The acids also affected yeast activity in dough resulting in lower specific volumes and harder bread crumb. To conclude, the antifungal activity of the FQ cannot be generalized because its antifungal power depends on the sensitivity of the mould species towards LA and AA.

A total of 684 Hisex Brown day-old chicks were studied. The chicks were randomly assigned into three groups as follows: (1) chicks with immediate feed access; (2) chicks with 48 h delay in feed access, and (3) chicks with 72 h delay in feed access. For each group, chicks were assigned into 4 replications of 57 birds each. Prior to feed access, the chicks were weighed. Samples of chicks were used to weigh yolk sac at 1, 3 and 7 days and to collect blood at 1, 3, 7, 14 and 56 days. Also, reared chicks were weighed weekly. The results indicated that chick weights decreased during the holding period. Yolk sac utilisation was similar between groups, while morbidity and mortality increased linearly with the duration of delay in feed access. At 56 days, chicks having delayed access to feed were lighter than those without delay in feed access. Serum concentration of glucose up to 14 days and of total protein and triglycerides until 56 days decreased with the increasing duration of delay in feed access. It can be concluded that delayed feed access is detrimental to the juvenile performance of layer-type chicks and has a negative age-related effect on the serum concentrations of glucose, triglycerides and total protein.

In a commercial hatchery, chicks (or poults) hatch over a 24–48 hour period. All chicks remain in the incubator until the majority of the chicks have emerged from the shell. Once removed from the i...

1. Because CO(2) during the second half of incubation is known to influence air cell and blood gases, and embryo development, it is postulated that post-hatch development and ascites sensitivity could also be influenced. 2. An ascites susceptible (A) and an ascites resistant (E) broiler line were incubated under standard incubation or high CO(2) conditions (up to 4%) from embryonic day (ED) 10 onwards. The embryonic development and the hatching process of these two lines were compared when incubated under standard or high CO(2) conditions from over the second half of incubation. 3. The A line, selected for high post-hatch growth rate, exhibited a higher relative embryo weight from ED10 until ED16, which was supported by a higher air cell pCO(2), lower air cell pO(2), higher corticosterone and thyroid hormones and earlier hatching time. 4. Incubation under high CO(2) increased air cell pCO(2), retarded yolk consumption, and decreased glycogen concentration in the liver at hatch. Hatchability decreased in both lines when incubated under high CO(2), due to an increased late mortality of embryos that died before IP. 5. These results suggest that the development and metabolism of CO(2)-incubated embryos differ from control incubated embryos.

The aim of this study was to investigate the influence of isoenergetic substitution between the three energy delivering macronutrients in pre-starter diets on performance and intermediary nutrient metabolism in broiler chickens. From hatch until 5 days of age, 600 chicks, collected during peak of hatch, were fed one of the three experimental pre-starter diets with isoenergetic (13 MJ metabolisable energy/kg) substitutions between fat (43 vs. 108 g/kg), protein (126 vs. 240 g/kg) and carbohydrates (391 vs. 510 g/kg). After 5 days, commercial grower and finisher diets were provided. Pre-starter composition influenced body weight until slaughter age, although not statistically verifiable. Broilers fed the low protein (LP) pre-starter had the lowest body weight in relation to chickens on the low carbohydrate or low fat pre-starter diet. After hatch, chicks on the LP pre-starter diet were able to use the residual yolk sac more rapidly to fulfil their protein requirement, which is reflected in small intestine and liver development. Also, plasma metabolite levels were influenced mostly by the LP pre-starter, indicating that the main focus for the requirements of newly hatched chicks should be on proteins. Furthermore, optimal nutrition during the first day's post-hatch should take into account the contribution of the yolk.

Embryonic development is a dynamic process that requires a fine balance between several factors in order to achieve an optimum hatchability and chick quality. These factors include the background o...

The chemosusceptibility and genetic polymorphism of Plasmodium falciparum populations from 48 patients hospitalized for malaria at the Hospital Principal in Dakar, Senegal were investigated during the 2002 malaria transmission season. Sixty-two percent of the isolates collected were from patients with severe malaria and 38% were from patients with mild malaria. In vitro activities of chloroquine, quinine, cycloguanil, atovaquone, mefloquine, halofantrine, and artesunate were evaluated. The prevalence of mutations in the Plasmodium falciparum dihydrofolate reductase (dhfr) and dihyropteroate synthetase (dhps) genes and the P. falciparum chloroquine resistance transporter (Pfcrt) gene associated with cycloguanil, pyrimethamine, sulfadoxine, and chloroquine resistance were estimated. The genetic polymorphism of the parasite populations was evaluated by analysis of the highly polymorphic regions of merozoite surface protein 1 (msp1) block 2 and msp2. Seventy percent of the isolates were assessed by an in vitro assay. Fifty-two percent of the isolates were chloroquine resistant, 45% were cycloguanil resistant, and 24% were atovaquone resistant. Four percent had low susceptibility to quinine. The Pfcrt and dhfr mutations were associated with in vitro chloroquine- and antimetabolic drug-resistant isolates, respectively. Approximately 70% of the isolates contained two or more clones. Genetic diversity of P. falciparum was high. The prevalence of allelic family K1 of msp1 was 68%. Isolates of P. falciparum were highly resistant to chloroquine, cycloguanil and atovaquone. The transmission rate of malaria in Dakar is low but a high degree of genetic polymorphism can increase severe malaria, as shown by persons coming to Dakar from areas highly endemic for malaria. Areas with urban malaria should use vector control measures and efficient chemoprophylaxis for non-immune populations.

Using DNA chip technology and real-time quantitative PCR, molecular profile of HBV strains infecting blood donors and patients in Dakar, Senegal was studied. All HBsAg-positive blood donors (n = 175) and all patients who presented with chronic hepatitis B (n = 29) between 1st June 2003 and 31st July 2003 were studied. One patient, a blood donor, was coinfected by HCV, and nine patients had anti-HDV antibodies. Few persons in either group were HBeAg-positive. Viral load values were relatively low but correlated with biochemical abnormalities. Patients were infected mainly by genotype E (72%). Patients infected by genotype A (28%) tended to be younger than other patients. There was no significant difference between the blood donors and the patients with hepatitis B as regards virological markers, including viral load, when the HBV genotype was taken into account. The BCP A1762T and G1764A mutations were found in four patients and one patient, respectively; the two mutations were never found in the same patient. The W28* mutation at position 1896 of the core was detected in 19 of the 32 genotyped patients, 18 (83%) of whom had genotype E infection. ALT levels were not influenced by HBV mutations. This study shows a low frequency of clinical signs in HBsAg-positive blood donors, a relatively low level of viral replication, and a high frequency of pre-core mutants in this West African population. These results underline the importance of molecular characterization of HBV infection as specific treatments become available in this region. J. Med. Virol. 78:329–334, 2006. © 2006 Wiley-Liss, Inc.

1. The aim of this study was to investigate if genetic predisposition to ascites interacts with changed incubation conditions, and how this might affect the post-hatch performance and ascites susceptibility. 2. An ascites sensitive (A) and resistant (E) broiler line were incubated under standard or high CO(2) conditions (up to 4%) from embryonic d 10 onwards. After hatch, chicks were exposed to cold from the 15th day of the rearing period to increase the incidence of ascites. 3. The A line had a higher post-hatch body weight from week three, higher blood pCO(2) from d 21, higher haematocrit at d 35 and d 42, and higher plasma corticosterone concentration from d 21 onwards, compared with the E line, regardless of incubation conditions, supporting the given selection criteria. Ascites mortality did not, however, differ between lines. 4. Incubation under high CO(2) conditions during the second half of incubation increased the ascites mortality, decreased body weight from week 4 onwards, affected venous blood pCO(2), decreased blood pO(2) from d 31, increased haematocrit at d 35 and d 42, and lowered the thyroxine and triiodothyronine concentrations at most sampling days. These effects were observed in both lines. The results suggested a metabolic programming of CO(2) incubated chickens which affected ascites susceptibility.

A multilevel housing system for broilers was developed, named Patio (Vencomatic BV, Eersel, the Netherlands), in which the hatching and brooding phase are combined. In a Patio system, climate conditions differ from those provided in the hatchers currently in use. We compared the physiology of broilers hatched in a hatcher or in a Patio system, and included the effects of hatching time. Eggs from 1 breeder flock were incubated until embryonic d 18 in a setter and subsequently placed in a hatcher or the Patio until the end of incubation. From each hatching system, 154 chicks were collected per hatching time, at 465 h (early), 480 h (midterm), and 493 h (late) of incubation, from which 24 chicks/group were decapitated for analyses of blood plasma and organ weights. The remaining 130 chicks in each group from both systems were individually labeled and placed together in the Patio system. All chicks were given access to feed and water directly after hatch and were housed up to d 45 to monitor growth. From embryonic d 18 until the end of incubation, average ambient temperature and RH were 38.1°C and 50.8% in the hatcher and 35.2°C and 29.7% in the Patio system. Glucose and corticosterone were slightly higher in hatcher chicks, whereas organ weights were not affected by the hatching system. Although hatchling weights were lower in hatchery chicks, growth from d 0 to 45 was not affected by the hatching system. In both systems, glucose increased with hatching time, whereas lactate and triiodothyronine levels decreased. Yolk weights decreased with hatching time, whereas absolute and relative weights of the yolk-free body, intestines, stomach, lungs, and heart increased, indicating more advanced maturation of organs. Growth up to d 21 was depressed in chicks in the late group, which was possibly related to lower thyroid hormone levels at hatching. We conclude that the hatching system had minor effects on hatchling physiology and that posthatch growth and livability were not affected. Because hatching time affected broiler physiology, it seems important to take hatching time into account in future studies related to hatchling physiology.

For hatcheries, not only is it important to have a high level of hatchability, but the quality of the chicks provided also has to be good, because broiler farmers are looking for chicks with a high growth potential, resulting in a greater slaughter yield at the end of the rearing period. However, chick quality has proven to be a difficult and subjective matter to define. Therefore, the aim of this study was to investigate the predictive value of different chick quality measurements for BW at slaughter age. Body weight, chick length, shank length, and toe length measurements as well as Tona score determination were performed on 1-d-old chicks and were linked to posthatch performance parameters. Different breeder lines (Cobb and Ross) and breeder ages (39, 42, and 53 wk of age) were used to investigate line and age effects. In addition, variability between people and repeatability in time of these quality measurements were determined. Body weight at 7 d of age appeared to be the best predictor of BW at slaughter age among all the quality measurements performed. Body weight at 1 d of age had the second greatest predictive value, closely followed by the ratio between BW at 1 d of age and chick length squared. Chick length and shank length both had low to no predictive value whatsoever for posthatch performance. The lack of significant correlations between the Tona score and posthatch performance could be explained by the absence of day-old chicks with anomalies (and thus a suboptimal Tona score) because a distinction had already been made, as is done in practice, between top-grade and lower grade chicks.

Despite thorough selection during the last decade, the incidence of ascites is still high in modern broiler strains. Although ascites occurs mostly at the end of the rearing period, there are indications that the etiology of this problem may have started during embryonic development. Recent studies have shown that the post-hatch performance of the broiler chick might be influenced by changing the environmental conditions in the incubator during embryonic development. This study investigated the effect of increasing incubator CO(2) concentration up to 0.7%, by nonventilation during the first 10 d of incubation, on the embryonic development of 2 commercial broiler strains (Cobb and SAS) differing in their susceptibility for ascites syndrome. The Cobb strain is suspected to be less susceptible than the SAS strain. Overall, the chick embryos of the Cobb strain had a faster development than those of the SAS strain as expressed by their higher BW from embryonic day (ED)10 until ED18. Nonventilation stimulated embryonic development resulting in higher embryonic BW, early hatch, and narrower spread of hatch in both strains. In the SAS strain, nonventilation improved hatchability by more than 10%. Gas composition of the air cell in the egg of the nonventilation groups (both Cobb and SAS) had higher partial pressure of CO(2) and lower partial pressure of O(2) from ED11 until ED14 compared with the ventilation groups. During the entire incubation period, partial pressure of CO(2) was higher in eggs of the Cobb strain compared with the SAS strain. Plasma triiodothyronine, thyroxine, and corticosterone levels were different at the end of the incubation period and during hatching due to nonventilation at the beginning of incubation. It is concluded that nonventilation during the first 10 d of incubation had a stimulatory effect on embryonic development of the 2 broiler strains with no effect of heart weights but with effects on hormone levels, air cell pressures, and hatching parameters.

The emergence of thermoregulation in avian species is a complex matter in which neural as well as hormonal processes are involved. In a previous paper, the neural aspects of primary avian thermoregulation were discussed. In this paper the role of the hypothalamus-pituitary-thyroid axis (HPT-axis) and the hypothalamus-pituitary-adrenal axis (HPA-axis) in the ontogeny of avian thermoregulation is evaluated. The regulatory mechanisms and different important hormones of both axes, which have stimulatory or inhibitory effects, are discussed. Because the onset of functionality of the thermoregulatory system is of great interest, the ontogeny and functionality of the hormonal axes are clarified. There is a great difference between precocial and altricial birds in hormonal events as well as in neural processes which are involved in the emergence of thermoregulation. In precocial avian species the HPT-axis becomes functional during the mid- to late embryonic period while the same axis only becomes fully functional during the first week post-hatch in altricial avian species. As early as the sixties, the emergence of homeothermy in chickens was investigated. It was concluded that the thyroid gland plays an important role in the thermoregulatory mechanisms of newly hatched chicks. More recent studies however were not able to show any direct effect of the thyroid hormones on the thermoregulation of day-old chicks, although blocking the conversion of T4 to T3 caused a decrease in body temperature in young chicks. Thyrotropin releasing hormone (TRH) is known to act in thermoregulation in mammals and several authors have found an effect of TRH on the metabolism of young and older chicks. However, the exact mechanism still remains unclear. Because the HPT- and the HPA-axis show close relationships, the role of the HPA-axis in the ontogeny of thermoregulation is also taken into consideration in this review. In mammals as well as in birds, corticotropin releasing hormone (CRH) is involved in the primary thermoregulation. We conclude that the HPT-axis has an important role in the ontogeny of avian thermoregulation. The exact role of the HPA-axis remains largely unclear although at least CRH is definitely of some importance.

In this study, broiler embryos were exposed during the second half of incubation [embryonic day (ED) 10 until ED18] to 4% CO(2). The CO(2) was set to reach 2% on ED11 and 4% from ED12 onward. Two experiments were conducted with the same setup. Embryo weight was measured and partial pressure of CO(2) and O(2) in the air cell was analyzed at several embryonic ages. Times of internal pipping, external pipping, and hatching were recorded. Chicks were raised until d 7 posthatch. Plasma corticosterone, triiodothyronine, and thyroxine concentrations were determined. Embryonic growth was not retarded and hatchability did not decrease in the CO(2)-incubated group, demonstrating that chicken embryos can tolerate high (4%) concentrations of CO(2) between ED10 and ED18. In the first experiment, partial pressure of CO(2) in the air cell was significantly higher in the CO(2) group on ED11, ED12, ED13, and ED14, but disappeared thereafter. This difference was not observed in the second experiment. A change in the hatching process of the CO(2) group was seen. Relative growths of newly hatched chicks until d 7 posthatch were equal in the CO(2) group and the control group. However, corticosterone and thyroxine concentrations were significantly higher in the CO(2)-incubated chicks on d 7 posthatch.

Recent studies show the importance of differential CO2 levels during the first half of incubation of chicken eggs on embryonic and postnatal growth. However, it is not known how external higher CO2 levels affect embryonic acid-base balance. In this study, the effect of an early rise in CO2, between 25th and 96th hour of incubation to 1.5% and maintained at that level until 240 h of incubation, was investigated on air cell gases, blood gas parameters from ED10 onwards and on embryonic growth and hatching parameters. Higher external CO2 concentrations resulted in a faster acidification of albumen resulting in a faster decrease of albumen pH with development, illustrating the capacity of albumen to cope with higher environmental CO2. Moreover, PCO2 in blood was higher in CO2 incubated embryos at embryonic day 10 and 11 but without a change in blood pH. The additional increase in plasma HCO3- concentration at day 10 and 11 was responsible for buffering the higher PCO2 in CO2 incubated embryos in order to stabilize pH. However, effects of hypercapnia on blood acid-base parameters extinguished 2 days after termination of high CO2 incubation. Embryonic growth was modestly accelerated which was reflected in higher embryonic weights at day 6 and 10 and a significant earlier hatching; hatchling weights were not different between treatment groups.

A severe epidemic of serogroup A meningococcus meningitis occurred in the northwest Central African Republic from January to March 1992. Strains from 24 patients were characterized using serotyping, testing of susceptibility to antibiotics, and multilocus enzyme electrophoresis. In 23 of the 24 patients the causal strain was found to be 4:P1.9/clone III-1. These results indicate that such strains continue to spread in Africa and have taken hold in areas outside the “meningitis belt.” This may be a consequence of changing climatic conditions.

(1994). Efficacy of ivermectin treatment of Loa loa filariasis patients without microfilaraemias. Annals of Tropical Medicine & Parasitology: Vol. 88, No. 1, pp. 93-94.

In an open study, the authors evaluate the efficacy and safety of Ivermectine (IVM) (oral doses of 200 microg/kg repeated after 1 month) in the treatment of Loa Loa infection without microfilar˦mia. All patients responded to the therapy. A recurrent œsinophilia occurred in 3 patients on the 8th month in the follow-up was well tolerated without any side effects.