Evaluation of five serological tests for the diagnosis of porcine brucellosis in French Polynesia

Porcine brucellosis due to Brucella suis biovar 1 raises important issues for pig breeders in French Polynesia. In this region, the disease is enzootic, spreads silently and engenders economic losses in infected farms as well as sporadic human cases. While serological tests are essential in surveillance and control programmes of animal diseases, to date none of the available tests have been shown to be reliable enough to be used as a gold standard in routine individual diagnosis of porcine brucellosis. Few studies about the estimation of the sensitivity and the specificity of porcine brucellosis screening tests have been published, none of them dealing with French Polynesia. The studied population included 1,595 pigs from French Polynesia. Five tests were evaluated: Rose Bengal test, fluorescence polarisation assay, indirect ELISA, and two competitive ELISAs (C-ELISA). The sensitivity and the specificity of each test were estimated. C-ELISA₂ was the most sensitive test (Se C-ELISA₂?=?0.954 [0.889; 0.992] 95 % credibility interval (CrI)) while both C-ELISA and Rose Bengal test (RBT) were the most specific ones (Sp C-ELISA₁?=?0.856 [0.806; 0.915] 95 % CrI; Sp C-ELISA₂?=?0.849 [0.817; 0.879] 95 % CrI; Sp RBT?=?0.853 [0.812; 0.898] 95 % CrI).     

Plasma lactate and purine derivatives accumulation after exercise of increasing intensity in standardbred horses

The aim of the experiment was to study the relationship between plasma lactate and allantoin accumulation in horses undergoing five exercises differing in intensity and length. Twenty-five adult trotter horses were used (18 males, two castrated, and five females), housed in three training centers. The horses were assigned to five groups: slow trot, over 2000 m (Group 1); slow trot over 1600 m (Group 2); fast trot over 1600 m (Group 3); fast trot over 2000 m (Group 4); fast trot over 2400 m (Group 5). Plasma was obtained from blood sampled at rest, at the end of the bout of exercise and after 15 and 45 minutes from the end of the bout of exercise and analyzed for glucose, lactate, uric acid, free fatty acids (FFA) and allantoin concentrations. Accumulations of plasma lactate and allantoin (mmol/sec) were calculated as difference between end of exercise and rest and between 45 minutes sample and rest, respectively.Ranking the intensity of exercise using the lactate concentrations at the end of exercise, the level of exertion was highest for Group 3 horses and lowest for Group 5 horses (20.9 and 2.8 mmol/l, respectively). At the end of exercise, glucose concentrations were much higher for horses undertaking the more intensive exercise (Groups 3 and 4 compared to Group 2). FFA concentrations were highest at the end of exercise for Groups 2 and 3 and after 15 minutes for Groups 4 and 5. Plasma uric acid and allantoin concentrations peaked 15 and 45 minutes from the end of exercise, respectively, independently of exercise intensity. The relationship between accumulation of plasma allantoin (y, dependent variables) and lactate (x, independent variable) was non-linear: y=0.15−2.61^*x+68.3^*x² (r²=0.900; se=0.19). This suggests that allantoin accumulation could be used together with plasma lactate to calibrate the workload to muscle conditions to prevent muscle injury.     

Milk production and composition,food consumption,and energy balance of postpartum crossbred Holstein-Gir dairy cows fed two diets of different energy levels

The objective of this study was to evaluate the production, consumption, and energy balance parameters of primiparous 3/4 and 7/8 Holstein × Gir (HG) dairy cows fed two diets of differing energy levels during the postpartum period. At the beginning of the study, 28 days prepartum, the average weight of both genetic groups was 498?±?12 kg and body condition score (BCS) was 3.5?±?0.05. At the end of the study, 61 days postpartum, the 3/4 HG cows had higher weight and body condition scores than the 7/8 HG (456?±?8 and 429?±?8 kg and 3.13?±?0.03 and 2.94?±?0.03 BCS for 3/4 HG and 7/8 HG, respectively). Milk from cows fed the high-energy diet had higher percentages of fat, protein, lactose, and total dry extract than cows fed the low-energy diet. Cows fed the high-energy diet had higher net energy intake (95.3?±?1.9 vs. 88.1?±?2.1 MJ/day) and higher energy balance (3.64?±?2.13 vs ??6.02?±?2.30 MJ/day). The 3/4 HG cows displayed higher energy for maintenance (33.1?±?0.4 MJ/day) than the 7/8 HG (31.5?±?0.5 MJ /day). In conclusion, although the primiparous 3/4 HG were heavier than the 7/8 HG and had a higher body condition score, no differences in milk produced up to 60 days postpartum were observed. The higher energy diet during the postpartum period increased energy balance, resulting in higher production of milk fat, protein, and lactose.

     

Effective plasma alfaxalone concentration to produce immobility in male neutered cats

Objective

To determine the effective plasma alfaxalone concentration for the production of immobility in cats.

Immune Status and Hepatic Antioxidant Capacity of Gilthead Seabream Sparus aurata Juveniles Fed Yeast and Microalga Derived β-glucans

This work aimed to evaluate the effects of dietary supplementation with β-glucans extracted from yeast (Saccharomyces cerevisiae) and microalga (Phaeodactylum tricornutum) on gene expression, oxidative stress biomarkers and plasma immune parameters in gilthead seabream (Sparus aurata) juveniles. A practical commercial diet was used as the control (CTRL), and three others based on CTRL were further supplemented with different β-glucan extracts. One was derived from S. cerevisiae (diet MG) and two different extracts of 21% and 37% P. tricornutum-derived β-glucans (defined as Phaeo21 and Phaeo37), to give a final 0.06% β-glucan dietary concentration. Quadruplicate groups of 95 gilthead seabream (initial body weight: 4.1 ± 0.1 g) were fed to satiation three times a day for 8 weeks in a pulse-feeding regimen, with experimental diets intercalated with the CTRL dietary treatment every 2 weeks. After 8 weeks of feeding, all groups showed equal growth performance and no changes were found in plasma innate immune status. Nonetheless, fish groups fed β-glucans supplemented diets showed an improved anti-oxidant status compared to those fed CTRL at both sampling points (i.e., 2 and 8 weeks). The intestinal gene expression analysis highlighted the immunomodulatory role of Phaeo37 diet after 8 weeks, inducing an immune tolerance effect in gilthead seabream intestine, and a general down-regulation of immune-related gene expression. In conclusion, the results suggest that the dietary pulse administration of a P. tricornutum 37% enriched-β-glucans extract might be used as a counter-measure in a context of gut inflammation, due to its immune-tolerant and anti-oxidative effects.     

To sea or not to sea? Multiple lines of evidence reveal the contribution of non‐diadromous recruitment for supporting endemic fish populations within New Zealand's longest river

相似文献   

Dietary organic acids blend alone or in combination with an essential oil on the survival,growth, gut/liver structure and de hemato‐immunological in Nile tilapia Oreochromis niloticus

This study evaluated the effects of dietary supplementation of organic acids blend (OAB) alone or in combination with essential oil, Lippia origanoides (OAE) for Nile tilapia fed supplemented diets for 30 days. Fish (1.1 ± 0.04 g) were fed control (Control), or OAB 0.5% or OAB 0.5% + essential oil 0.125% (OAE) respectively. At the end of the experiment, samples were collected for de hemato‐immunological, histological analysis of the intestine and liver, as well as microbiology of the intestine. The pH of the diets supplemented with OAB and OAE reduced 0.92 and 0.19 respectively. The growth and FCR were unaffected by the treatments, but survival was significantly higher in the OAB treatment. Fish fed the OAB diet showed reduced concentration of total heterotrophic bacteria and Pseudomonas sp. in the intestine. Increased glucose in fish fed OAB and high number of circulating monocytes in fish fed OAE diet were observed. The anterior intestine of fish fed OAE diet showed larger number of goblet cells and increased villi height. The diet supplemented with OAB, mainly, improved the intestinal health and survival of tilapia juveniles and can be used in juvenile production.     

Schizochytrium as a replacement for fish oil in a fishmeal free diet for jade perch,Scortum barcoo (McCulloch & Waite)

A 10‐week trial was conducted to determine the response of juvenile jade perch Scortum barcoo on the replacement of dietary fish oil (FO) in a fishmeal free diet. Three iso‐nitrogenous, isocaloric and isolipidic diets were formulated, each containing a different primary fat source: FO, linseed oil (LO), and a mixture of Schizochytrium and LO. The substitution of FO with the mixture of Schizochytrium and LO did not cause a difference in growth. However, there was an 8% reduction in weight gain in fish fed dietary LO, indicating that juvenile jade perch do require a minimal concentration of dietary n‐3 highly unsaturated fatty acids (HUFA). Fish fed the Schizochytrium diet stored more efficient n‐3 HUFA and in particular DHA in their flesh, and retained a higher fillet recovery compared to fish fed FO. In addition, we demonstrated that jade perch are able to produce both n‐3 HUFA and n‐6 HUFA when dietary PUFA are present. Fish fed the LO diet for 10 weeks contained the lowest amount of n‐3 HUFA in fillets among dietary treatment groups. However, feeding these fish the Schizochytrium diet for an additional 4 weeks increased the n‐3 HUFA content towards the same concentration of n‐3 HUFA found in the flesh of fish fed FO, without affecting the sensory properties of the fillets. In contrary, feeding the Schizochytrium diet for a continuous period of 14 weeks lowered overall sensory property scores.