The challenge of large litters on the immune system of the sow and the piglets

The use of hyperprolific sow lines has increased litter size considerably in the last three decades. Nowadays, in some countries litters can reach up to 18–20 piglets being a major challenge for the sow's physiology during pregnancy, parturition and lactation. The increased number of piglets born per litter prolongs sensibly the duration of farrowing, decreases the piglets’ average weight at birth and their vitality, increases the competition for colostrum intake and can affect negatively piglets’ survival. This review aims to describe how large litters can affect the immune system of the sow and the piglets and proposes measures to improve this condition.     

Lectin histochemical pattern on the normal and cystic ovaries of sows

The lectin histochemical pattern (LHP) was characterized and compared in normal and cystic ovaries of sows. Six biotinylated lectins (PNA, SBA, WGA, RCA‐1, DBA and UEA‐1) were used on tissue sections. In the normal ovaries, the reaction to UEA‐1 and SBA was mild to moderate in mesothelial and endothelial cells. RCA‐1 staining was mild to moderate in theca interna of growing follicles, corpora luteum and mesothelium. In addition, this lectin presented strong reaction in endothelial cells, granulosa cells of atretic follicles, zona pellucida of growing follicles and plasma. DBA showed strong intensity in mesothelial and endothelial cells. There was mild to moderate reactivity to WGA in granulosa cells, corpus luteum and theca interna of follicles in development, and moderate in zona pellucida, in granulosa cells of atretic follicles and mesothelium. PNA staining was mild to moderate in oocytes and in the adventitia and media of medullary arteries. Changes in the LHP of the cystic ovaries were noted; however, there were no differences in these findings between the follicular and luteinized cysts. UEA‐1 reactivity in the cystic ovaries was moderately reduced in the mesothelial and endothelial cells, whereas there was mild reduction in the DBA staining in the granulosa cells. Reaction to RCA‐1 and WGA in the cysts also was decreased in theca interna, zona pellucida and granulosa cells of atretic follicles. Furthermore, endothelium and theca interna in the cystic ovaries presented mild reduction of marcation to SBA, whereas there was decreased reactivity to PNA in the oocytes and adventitia and media layers of the medullary arteries. The results of the current study show that cysts modify the LHP in swine ovaries. These changes of glycoconjugates in many ovarian structures could modify diverse process and may be one of the reasons for decreased fertility in sows.     

Photoprotection of vitamins in skimmed milk by an aqueous soluble lycopene-gum Arabic microcapsule

Riboflavin (Rf)-mediated photosensitized degradation of vitamins A and D3 in skimmed milk under illumination with a white fluorescence lamp was studied by using the HPLC technique. The photosensitized degradation of both vitamins followed first-order kinetics, and the temperature effect on the observed photodegradation rate constant allowed the determination of the activation energy Ea as being 4 and 16 kcal/mol for vitamins A and D3, respectively. The addition of lycopene microencapsulated by spray-drying with a gum arabic-sucrose (8:2) mixture (MIC) produced a reduction of ca. 45% in the photosensitized degradation rate of both vitamins. Front-face fluorescence experiments showed the same photoprotection factor in the degradation of Rf itself, indicating that the photodegradation mechanism involved Rf-mediated reactive species, such as the excited triplet state of Rf, 3Rf*, and/or singlet molecular oxygen, 1O2. The interaction of both 3Rf* and 1O2 with MIC was evaluated in aqueous solutions by using laser-induced time-resolved absorption or emission spectroscopy, and the contribution of an inner-filter effect in the presence of MIC in skimmed milk was evaluated by diffuse reflectance spectroscopy. The main operating mechanism of photoprotection is due to the deactivation of 3Rf* by the proteic component of gum arabic; thus, gum arabic based microcapsules could be used to improve the photostability of milk during its storage and/or processing under light.     

Characterization of volatiles in extracts from oak chips obtained by accelerated solvent extraction (ASE)

Sixteen commercially available oak chips, differing in origin (French or American) and toasting level, were extracted by an accelerated solvent extraction method and characterized by their volatile composition. About 80 compounds were identified and quantified, a great part of them from the thermodegradation of lignin and cellulose. One furanone (solerone) and two C-13 norisoprenoids (3-oxo-alpha-ionol and a 3-oxoretro-alpha-ionol isomer) were also tentatively identified and reported for the first time in toasted wood. Quantitative data demonstrated the oak chips to be not so different from the composition of light- or medium-toasted wood barrels, which was reported by other authors. The same data suggest that toasting level had the strongest influence on the volatile composition of chip samples. Phenyl ketones, volatile phenols, and some furanic compounds were the most influenced. On the other hand, the influence of wood origin was found to be weaker.     

A simple molecular method for discriminating common filarial nematodes of dogs (Canis familiaris)

Accurate diagnosis of canine filariosis is essential for choosing correct therapeutic approach. Therefore, reliable methods for discriminating among the different filarial infections in dogs are needed. The authors report simple and highly specific molecular methods that identify the three most common filarial nematodes of European dogs: Dirofilaria immitis, D. repens and Acanthocheilonema (syn. Dipetalonema) reconditum, based on (1) PCR amplifications of mitochondrial DNA (12S rDNA and coxI) with general filarial primers followed by digestion with restriction enzymes that generates band polymorphisms clearly discriminating the three species and (2) PCR amplifications with species-specific primers to support the restriction analysis, in particular in the case of multiple infections.     

Endogenous ascorbic acid modulates meristem reactivation in white spruce somatic embryos and affects thymidine and uridine metabolism

Previously, we demonstrated that, in some cell lines, exogenous applications of ascorbic acid (ASC) enhance the conversion frequency of white spruce (Picea glauca (Moench) Voss) somatic embryos, by stimulating mitotic activity in the apical meristems. To examine this event in more detail, we investigated the effects of ASC on de novo, salvage and degradation pathways of pyrimidine metabolism by following the metabolic fate of (14)C-labeled orotic acid, thymidine, uridine and uracil in shoot and root poles of germinating embryos, after altering the cellular ASC content of the embryos. Alterations in endogenous ASC content did not affect the utilization of either orotic acid or uracil, but affected the metabolism of thymidine and uridine. Specifically, a lowering of endogenous ASC content by applications of lycorine (L), an inhibitor of the last enzyme of the ASC de novo biosynthetic pathway, resulted in a lower embryo conversion frequency, as well as a reduced percentage of thymidine and uridine incorporated into nucleotides and nucleic acids. The reduction in thymidine and uridine anabolism was mainly ascribed to the decreased activities of thymidine kinase (TRK) and uridine kinase (URK), the respective salvage enzymes of thymidine and uridine, measured in L-treated embryos. These effects were solely a result of a decrease in endogenous ASC content because applications of ascorbic acid plus lycorine (ASC + L) increased embryo conversion frequency, thymidine and uridine salvage activities, and TRK and URK activities to near control values. Inclusion of exogenous ASC in the germination medium did not affect the percentage of embryos able to convert to viable plantlets, although it increased thymidine and uridine utilization for nucleic acid synthesis in the shoot and root poles of the embryos. Taken together, these findings confirm that cellular ASC plays a key role in the reactivation of the apical meristems of germinating white spruce somatic embryos.     

Efficacy of dinotefuran, permethrin and pyriproxyfen combination spot-on against Aedes aegypti mosquitoes on dogs

A spot-on formulation combining permethrin, dinotefuran and pyriproxyfen (Vectra 3D? spot-on solution for dogs - one 10-25kg pipette contains 196mg dinotefuran, 1429mg permethrin and 17mg pyriproxyfen) was evaluated in adult Beagle dogs in a study designed to measure its efficacy to control Aedes aegypti (anti-feeding effect and mortality effect). The trial was performed according to Animal Welfare and Good Clinical Practice. Twelve dogs (five males and seven female, >3 years old, weighing 8.8-13.0kg) were randomly allocated to treatment groups on pre-treatment mosquito counts: six dogs served as untreated controls, and six dogs were treated with the test formulation. Treatment consisted of applying a combination formulation to deliver at least 46.6mgkg(-1) permethrin, 6.40mgkg(-1) dinotefuran and 0.57mgkg(-1) pyriproxyfen. The combination is designed to control fleas, ticks, sand flies and mosquitoes. Each dog was infested with approximately 100 adult unfed A. aegypti once before treatment (day 6) then at 1, 7, 14, 21 and 28 days post-treatment. Counts and engorgement determination of dead and live mosquitoes were performed after 1h exposure period. In the treated group (group A), the repellency effect of the product based on engorgement status (anti-feeding effect), was 91.5%, 94%, 94.7%, 94% and 87% at 1, 7, 14, 21 and 28 days post-treatment. Mortality effect or insecticidal efficacy calculated at the end of the 1-h exposure was almost identical when calculated 24h after the 1-h exposure and remained above 93% until the end of the in-life phase. No adverse events were observed following treatment, including observations conducted 2, 4 and 24h after the last dog was treated.     

Perception of dogs’ stress by their owners

Questionnaires potentially have a broad applicability in measuring stress levels in dogs, as owners know their dogs’ behavior and personality better than anyone else. The aim of this research was to evaluate how owners perceive stress in their dogs through understanding of displayed behaviors.The survey was carried out using 1,190 questionnaires completed by dog owners. More than half of respondents were able to correctly identify stress as a short- or long-term alteration of the psychophysical equilibrium that can develop into illness. This ability was higher with higher educational levels. The behavioral indicators of stress most frequently identified by owners were trembling and whining, followed by aggressiveness, excessive barking, and panting. More subtle behaviors such as looking elsewhere, turning head, yawning, and nose licking were more rarely reported, suggesting that few owners are able to correctly interpret and intervene in early stages of stress. The vast majority of respondents indicated that dogs were stressed seldom or only in specific situations. Men generally considered their dogs as experiencing low stress more often than did women, whereas women considered their dogs as being moderately stressed more often than did men.An owner’s ability to recognize behavioral signs of stress is important, as it enables the owner to help the animal to avoid welfare problems, such as stressful situations, and favors a rapid recovery of psychophysical homeostasis by interrupting the progression to overstress and distress. The results show that some owners can help in protecting the welfare of their dogs, but that many owners would benefit from educational efforts to improve their ability to interpret their dogs’ behavior.     

How Do Horses Appraise Humans' Actions? A Brief Note over a Practical Way to Assess Stimulus Perception

Heart rate (HR) is considered to be an effective tool for assessing animals' emotional response to a stimulus. We investigated changes in HR during a series of handling procedures (grooming test) in horses that had different experiences of human interaction. We used four groups of horses: grazing horses (group A), school horses (group B), six ponies, traditionally trained (group C), and six ponies, trained with modulated stimulus intensity (group D). An HR monitor was applied to each horse. The operator began the grooming test, standardized at the following points: (1) trainer's entry into the enclosure/paddock, (2) halter fastened, (3) start of grooming, (4) end of grooming, (5) saddling, and (6) inserting the bit. Group A repeated the grooming test twice: group A1 with a known operator and group A2 with an unknown operator. The data were compared by using analysis of variance (ANOVA) tests. The results showed a significant increase in HR (P ≤ .05) at point 2 compared with baseline in all groups except group D. Other significant differences were found at all points between groups A1 and A2, groups A2 and B, groups A1 and C, groups B and C, and at points 5 and 6 between groups A2 and C, as well as between groups C and D. Even when a scientific assessment of the increase in the HR is of primary importance, the use of this physiologic parameter may be helpful in assessing the horse's perceptions of stimuli presented by people during handling. Our results show that it is not the action “per se” that is important, but the manner in which horses perceive and appraise such actions in relation to the environment and their subject's experiences.     

Feeding sows with high fibre diet around farrowing and early lactation: impact on intestinal activity, energy balance related parameters and litter performance

The effects of fibre in diets for periparturient sows are poorly documented. Three weeks before farrowing, 41 sows (LACT) were fed a diet containing 3.8% crude fibre. Other 40 sows (FIBRE) received a diet containing 7% crude fibre. We estimated the intestinal activity of the sows with a daily qualitative evaluation of their faeces. The FIBRE group had a qualitative faeces score value of 2.1 ± 1.3 and the LACT group had a value of 1.2 ± 1.1 (P < 0.001). Individual daily water consumption was higher in the FIBRE group than in the LACT group (P < 0.001). Piglet weight gain at day 5 was higher in the FIBRE group (P < 0.05). The energy balance related parameters did not differ between the treatments.Concluding, diets containing more fibre can be successfully used around farrowing reducing prolonged constipation of sows with no negative effect on their energy balance related parameters.