Avoiding congestion in freight transport planning: a case study in Flanders

A substantial increase in transport intensity for passenger and freight traffic has been observed during the last decades and research confirms that this trend will continue in the years to come. Economic centres have turned into heavily congested areas. The freight transport sector incurs excessive waiting times on the road as well as at intermediate stops (e.g. sea terminals, loading or unloading points). This may cause economic losses and environmental damages. Waiting times may be avoided by taking into account congestion in freight transport planning. Vehicle routing problems arise when several pickup and delivery operations need to be performed, mainly by truck, over relatively short distances [1]. Congestion leads to uncertain travel times on links and uncertain waiting times at pickup or delivery locations. Peak hours may be avoided on congested road segments by changing the order in which customers are served. On the other hand, time slots at customer sites may be renegotiated, creating more flexibility to avoid congestion on the road and at customer stops. The objective of this paper is to estimate the benefits of taking congestion into account in transport planning and to quantify the impact of delivery restrictions on transport costs. A highly congested road network raises the need for robust vehicle routing decisions. Current traffic conditions give rise to uncertain travel times. The reliability of travel time on a route is one of the dominant factors affecting route and departure time choices in passenger transport [2]. Similarly, in freight transport the reliability of travel times may be taken into account when planning vehicle routes. In this paper congestion is modelled as time-dependent travel times. These travel times take into account the dynamics of the time lost due to congestion using the Bureau of Public Roads (BPR) function, which is commonly-used for relating travel times to increases in travel volume [3]. The Time Dependent Vehicle Routing Problem (TDVRP) will be studied as a deterministic planning problem taking into account peak hour traffic congestion. Solution methods for the TDVRP have been focused on heuristic approaches [4, 5, 6, 7]. Kok [8] applies a restricted dynamic programming heuristic to solve a TDVRP. In this paper a heuristic algorithm will be presented to solve problem instances of realistic size. Next, this algorithm will be applied to perform a sensitivity analysis to identify which congestion avoiding strategies have a large influence on the objective function. Shippers may adapt the way they plan their transport as a strategy to avoid congestion. For example, time windows at customer locations may be renegotiated, departure times at the depot may be questioned or the assignment of customers to routes and the order in which customers are served may be changed. The proposed methodology will be demonstrated with a Flemish case study

Changes in back fat thickness during late gestation predict colostrum yield in sows

Directing protein and energy sources towards lactation is crucial to optimise milk production in sows but how this influences colostrum yield (CY) remains unknown. The aim of this study was to identify associations between CY and the sow’s use of nutrient resources. We included 37 sows in the study that were all housed, fed and managed similarly. Parity, back fat change (ΔBF), CY and performance parameters were measured. We obtained sow serum samples 3 to 4 days before farrowing and at D1 of lactation following overnight fasting. These were analysed for non-esterified fatty acids (NEFA), urea, creatinine, (iso) butyrylcarnitine (C4) and immunoglobulins G (IgG) and A (IgA). The colostrum samples collected 3, 6 and 24 h after the birth of the first piglet were analysed for their nutrient and immunoglobulins content. The technical parameters associated with CY were parity group (a; parities 1 to 3 =value 0 v. parities 4 to 7 =value 1) and ΔBF D85-D109 of gestation (mm) (b): CY (g) =4290–842a–113b. ( R2=0.41, P<0.001). The gestation length ( P<0.001) and the ΔBF between D109 and D1 of lactation (P=0.050) were identified as possible underlying factors of the parity group. The metabolic parameters associated with CY were C4 at 3 to 4 days before farrowing (a), and 10logC4 (b) and 10logNEFA (c) at D1 of lactation: CY ( g) =3582–1604a+1007b− 922c ( R2=0.39, P=0.001). The colostrum composition was independent of CY. The negative association between CY and ΔBF D85-D109 of gestation could not be further explained based on our data. Sows that were catabolic 1 week prior to farrowing seemed unable to produce colostrum to their full potential. This was especially the case for sows with parities 4 to 7, although they had a similar feed intake, litter birth weight and colostrum composition compared with parities 1 to 3 sows. In conclusion, this study showed that parity and the use of body fat and protein reserves during late gestation were associated with CY, indicating that proper management of the sow’s body condition during late gestation could optimise the intrinsic capacity of the sow’s CY

In vitro rumen simulations show a reduced disappearance of deoxynivalenol, nivalenol and enniatin B at conditions of rumen acidosis and lower microbial activity

Ruminants are generally considered to be less susceptible to the effects of mycotoxins than monogastric animals as the rumen microbiota are capable of detoxifying some of these toxins. Despite this potential degradation, mycotoxin-associated subclinical health problems are seen in dairy cows. In this research, the disappearance of several mycotoxins was determined in an in vitro rumen model and the effect of realistic concentrations of those mycotoxins on fermentation was assessed by volatile fatty acid production. In addition, two hypotheses were tested: (1) a lower rumen pH leads to a decreased degradation of mycotoxins and (2) rumen fluid of lactating cows degrade mycotoxins better than rumen fluid of non-lactating cows. Maize silage was spiked with a mixture of deoxynivalenol (DON), nivalenol (NIV), enniatin B (ENN B), mycophenolic acid (MPA), roquefortine C (ROQ-C) and zearalenone (ZEN). Fresh rumen fluid of two lactating cows (L) and two non-lactating cows (N) was added to a buffer of normal pH (6.8) and low pH (5.8), leading to four combinations (L6.8, L5.8, N6.8, N5.8), which were added to the spiked maize substrate. In this study, mycotoxins had no effect on volatile fatty acid production. However, not all mycotoxins fully disappeared during incubation. ENN B and ROQ-C disappeared only partially, whereas MPA showed almost no disappearance. The disappearance of DON, NIV, and ENN B was hampered when pH was low, especially when the inoculum of non-lactating cows was used. For ZEN, a limited transformation of ZEN to alpha-ZEL and beta-ZEL was observed, but only at pH 6.8. In conclusion, based on the type of mycotoxin and the ruminal conditions, mycotoxins can stay intact in the rumen

Integration of inland waterway transport in the intermodal supply chain: a taxonomy of research challenges

This paper identifies research opportunities which will enable the further integration of inland waterway transport in the intermodal supply chain. Intermodal transport may be interpreted as a chain of actors who supply a transport service. Inland navigation can play a crucial role in increasing supply chain service performance. A first group of research challenges lies in the evolving relationship between transport geography and logistics activities. The next set of research challenges has the objective to encourage efficient operations in IWT: development of a system wide model for IWT, integration of operational planning systems and analysis of bundling networks. A third group of research efforts is directed towards shippers and consignees who use the intermodal transport chain to send or receive their goods: further development of models that integrate intermodal transport decisions with supply chain decisions and creation of green supply chains. A fourth cluster of research challenges concerns the problem domain of external cost calculations. Finally detailed time series data on freight transport should be collected to support these future research tracks

Prophylactic use of meloxicam and paracetamol in peripartal sows suffering from postpartum dysgalactia syndrome

Postpartum dysgalactia syndrome (PPDS) is a major economic problem in modern sow farms. General treatment of PPDS consists of the use of oxytocin to promote milk ejection and non-steroidal anti-inflammatory drugs (NSAIDs) to alleviate inflammatory processes. So far, studies investigated the use of a single administration of NSAIDs after parturition in healthy and non-healthy sows. The current study investigated whether administration of meloxicam or paracetamol in sows prior to parturition improves sow and piglet health as well as performance in a farm with PPDS problems in sows. Sixty sows and 978 piglets from a Belgian farrow-to-finish farm were enrolled. Sows were randomly divided into three groups: a non-treated control group, a meloxicam-treated group and a paracetamol-treated group. Treatment was administered orally for 7 days from gestation day 113 onwards. Performance and health parameters investigated in sows were gestation length, farrowing duration, litter characteristics, colostrum yield and quality (Immunoglobulin G), litter weight gain, weaning-to-estrus interval, pregnancy rate, rectal temperature, acute phase proteins and inflammatory markers serum amyloid A, haptoglobin, interferon γ, interleukin 1β and 6 backfat, constipation and feed refusal. Performance and health parameters in piglets were birthweight, average daily weight gain, colostrum intake and mortality. Paracetamol-treated sows showed a significantly (P = 0.04) lower rectal temperature (mean ± SD: 38.09 ± 0.18°C) than the meloxicam-treated sows (38.24 ± 0.18°C), but not than the control group (38.22 ± 0.18°C). Sows of the paracetamol-treated group had a significantly (P = 0.001) longer gestation length (116.3 ± 0.9 days) than sows of the control group (115.3 ± 0.6 days), but not than meloxicam-treated sows (115.9 ± 0.9 days). No significant differences between the three groups were found for all the other parameters. In conclusion, the prophylactic oral administration of either meloxicam or paracetamol for 7 days starting 2 days prior to farrowing did not show beneficial effects on both health and performance parameters of sows and piglets

Prevalence and risk factors of claw lesions and lameness in pregnant sows in two types of group housing

Claw lesions and lameness in sows are an important welfare concern as well as a cause of considerable economic loss. These problems are more common in group housing than in individual housing systems. Given that group housing for gestating sows will become mandatory in the EU from 2013 onwards, the aim of the present study was: (1) to determine the prevalence of lameness and claw lesions in sows housed in groups during gestation, and (2) to analyze whether the type of group housing system and sow-related factors were associated with lameness and claw lesions. Eight Belgian pig herds with group housing of gestating sows were selected. Four herds used pens with electronic sow feeders (dynamic groups), the other four herds kept their sows in free access stalls (static groups). All sows were visually examined for lameness at the end of gestation. Claw lesions were scored after parturition. Information about feed, housing conditions and culling (strategy) was collected, as well as information about parity and breed. Of all 421 assessed sows, on average 9.7% (min. 2.4%, max. 23.1%) were lame. Almost 99% of the sows had one or more claw lesion with overgrowth of heel horn (93%) and cracks in the wall (52%) as the most prevalent lesions. Neither for lameness nor claw lesions was significant differences found between the two types of group housing. Lameness decreased while the mean claw lesion score increased with ageing. These results suggest that lameness can be caused by reasons other than claw lesions, especially in older sows. Although no difference was found between the two types of group housing, a huge variation between herds was observed. Moreover, as the prevalence of lameness and claw lesions in group housing is quite high and group housing will become mandatory in 2013, further investigation on risk factors of locomotor disorders in sows is necessary

Evaluation of the agreement between Brix refractometry and serum immunoglobulin concentration in neonatal piglets

Neonatal piglets lack immunoglobulins at birth. Sufficient colostrum intake (CI) and immunoglobulin absorption are essential for an appropriate passive transfer of immunity via the colostrum. Most methods to measure immunoglobulins in serum of piglets are labour-intensive, expensive or imprecise and not designed for on-farm use. The present diagnostic test study evaluated digital Brix refractometry to measure immunoglobulins in serum of neonatal piglets and to suggest thresholds for different serum immunoglobulin concentration. Additionally, agreements between Brix refractometry and optical refractometer (serum total protein, STP) and between Brix refractometry and ELISA (immunoglobulin G. IgG) were also investigated. Forty-five sows and 269 piglets from three different farms were enrolled in the study. Piglets were weighed at birth and 24 h later to calculate the Cl. Serum was collected at 24 h after birth and analysed for STP, gamma-globulins (electrophoresis), % Brix and IgG. In piglets, median (interquartile range, IQR) CI was 412 (196) g per piglet Median (IQR) STP, gamma-globulin and % Brix concentrations in piglet serum were 60 (11) g/L, 35 (10) g/L and 8 (2) %, respectively. Average (+/- SD) IgG concentration was 49 +/- 23 g/L Passing-Bablok regression revealed a strong concordance between % Brix and STP (Kendall's tau (T): 0.620, P < 0.0001, n = 267) and % Brix and gamma-globulin concentration (Kendall's T: 0.575, P < 0.0001, n = 267). The agreement between the Brix refractometer and IgG concentration was poor (Kendall's T: 0267, P < 0.0001, n = 269). Receiver operating characteristic curves were performed to evaluate test characteristics of Brix refractometry for three gamma-globulin cut-off values, i.e. 10, 20 and 30 g/L. The % Brix cut-off values resulting in the optimal combination of sensitivity and specificity were 5.4 (100 and 985%), 7.0 (100 and 89.3%) and 7.9 (90.1 and 80.6%), respectively. In conclusion. digital Brix refractometry is a sufficiently fast and practical method to assess serum gamma-globulin concentrations in neonatal piglets on-farm and to evaluate them by considering the thresholds found in this study. Further studies are needed to validate those thresholds regarding piglet's survival in the pre-weaning period. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of The Animal Consortium

Selenium digestibility and bioactivity in dogs : what the can can, the kibble can't

There is a growing concern for the long-term health effects of selenium (Se) over-or underfeeding. The efficiency of utilization of dietary Se is subject to many factors. Our study in dogs evaluated the effect of diet type (canned versus kibble) and dietary protein concentration on Se digestibility and bioactivity. Canned and kibble diets are commonly used formats of dog food, widely ranging in protein concentration. Twenty-four Labrador retrievers were used and four canned and four kibble diets were selected with crude protein concentrations ranging from 10.1 to 27.5 g/MJ. Crude protein concentration had no influence on the digestibility of Se in either canned or kibble diets, but a lower Se digestibility was observed in canned compared to kibble diets. However, the biological activity of Se, as measured by whole blood glutathione peroxidase, was higher in dogs fed the canned diets than in dogs fed the kibble diets and decreased with increasing crude protein intake. These results indicate that selenium recommendations in dog foods need to take diet type into account

Extensive clinical, hormonal and genetic screening in a large consecutive series of 46, XY neonates and infants with atypical sexual development

Background: One in 4500 children is born with ambiguous genitalia, milder phenotypes occur in one in 300 newborns. Conventional time-consuming hormonal and genetic work-up provides a genetic diagnosis in around 20-40% of 46, XY cases with ambiguous genitalia. All others remain without a definitive diagnosis. The investigation of milder cases, as suggested by recent reports remains controversial. Methods: Integrated clinical, hormonal and genetic screening was performed in a sequential series of 46, XY children, sex-assigned male, who were referred to our pediatric endocrine service for atypical genitalia (2007-2013). Results: A consecutive cohort of undervirilized 46, XY children with external masculinization score (EMS) 2-12, was extensively investigated. In four patients, a clinical diagnosis of Kallmann syndrome or Mowat-Wilson syndrome was made and genetically supported in 2/3 and 1/1 cases respectively. Hormonal data were suggestive of a (dihydro) testosterone biosynthesis disorder in four cases, however no HSD17B3 or SRD5A2 mutations were found. Array-CGH revealed a causal structural variation in 2/6 syndromic patients. In addition, three novel NR5A1 mutations were found in non-syndromic patients. Interestingly, one mutation was present in a fertile male, underlining the inter-and intrafamilial phenotypic variability of NR5A1-associated phenotypes. No AR, SRY or WT1 mutations were identified. Conclusion: Overall, a genetic diagnosis could be established in 19% of non-syndromic and 33% of syndromic cases. There is no difference in diagnostic yield between patients with more or less pronounced phenotypes, as expressed by the external masculinisation score (EMS). The clinical utility of array-CGH is high in syndromic cases. Finally, a sequential gene-by-gene approach is time-consuming, expensive and inefficient. Given the low yield and high expense of Sanger sequencing, we anticipate that massively parallel sequencing of gene panels and whole exome sequencing hold promise for genetic diagnosis of 46, XY DSD boys with an undervirilized phenotype