Cages For Collection Research Articles

Effects of substitution of soybean meal-alfalfa-maize by a combination of field bean or pea with hard wheat bran on digestion and growth performance in rabbits in Algeria

The aim of the trial was to study the effects of replacement of a soybean meal-alfalfa-maize based diet by a mixture of field bean (g/kg as fed: 257 crude protein [CP], 139 neutral detergent fibre [NDF]) or pea (g/kg as fed: 203 CP, 122 NDF) combined with hard wheat bran (g/kg as fed: 140 CP, 396 NDF) and without supplementation of synthetic DL-methionine, on diet digestibility, growth and slaughter traits of growing rabbits. Three diets were formulated: a control diet mainly consisting of 15% of soybean meal, alfalfa and maize (SBM15 diet; g/kg as fed: 161 CP and 267 NDF) and 2 experimental diets based on 26% of field bean (FB26 diet; g/kg as fed: 167 CP and 250 NDF) or 30% of pea (P30 diet; g/kg as fed: 167 CP and 255 NDF) as main protein source, and completed with hard wheat bran (34 and 40%, respectively for FB26 and P30 diets) partly replacing alfalfa and maize. Diets were distributed ad libitum to 3 groups of 40 mixed-sex growing rabbits of Algerian white population, placed in collective cages (4 rabbits/cage) from weaning (28 d, mean weight: 614±112 g) until 77 d of age (slaughter). Faecal digestibility was measured between 42 and 46 d of age in 7 rabbits/group. Gross energy and crude protein digestibility coefficients were similar for SBM15 and FB26 diets (78.6 and 86.4%, respectively) and lower for P30 diet (75.1 and 83.6%, respectively; P≤0.03). Treatments had no effect (P=0.12) on mortality rate, which was on av. 9.2%. Treatments did not affect growth performance from 28 to 77 d of age (30.8 g/d) or feed intake (mean 94.6 g/d), but feed conversion ratio was higher for rabbits fed FB26 and P30 diets compared to those fed SBM15 diet (3.13 vs. 2.94; P=0.006). The dressing out percentages (mean 66.6%) and the muscle/bone ratio (6.8) were similar for the 3 groups of rabbits. In conclusion, the substitution of soybean meal-alfalfa-maize by a combination of field bean or pea with hard wheat bran, without methionine supplementation, does not seem to affect growth, nor the slaughter performances of the local growing rabbits. However, digestion of pea diet was reduced and feed efficiency of FB26 and P30 diets was impaired.

Radiofrequency renal nerve ablation decreases blood pressure in SHR accompanied by increased urinary sodium excretion (857.4)

We have shown that radiofrequency catheter ablation of the renal arteries (RF‐RDN) decreases blood pressure (BP) in spontaneously hypertensive rats (SHR). Here, we studied the effects of RF‐RDN on changes in water and sodium excretion and urinary angiotensinogen levels in SHR with established hypertension. Methods Nineteen‐week old male SHR were instrumented with telemetry probes for measurement of BP. After 1‐week, control BP was measured. The next day SHR randomly received either bilateral Sham‐RDN (n=5) or RF‐RDN (n=6) of the renal arteries (Biosense Webster Stockert 70 generator and RF‐probe). BP (Systolic, SBP; Diastolic, DBP) was then measured for 2 weeks. Rats were then placed in metabolic cages for collection of urine and measurement of 24‐hr water and sodium balance. Results BP was significantly decreased in RF‐RDN SHR (2 weeks; ΔSBP, ‐12±5; ΔDBP, ‐9±4 mmHg) as compared to sham SHR (2 weeks; ΔSBP, ‐2±2; ΔDBP, 2±2 mmHg). RF‐RDN SHR increased urinary sodium excretion (RF‐RDN, 0.33±0.02; Sham, 0.25±0.03 mEq/day) and food intake (RF‐RDN 21±1; Sham 17±1 g/day). However, there were no significant differences between groups in 24‐hr daily water (RF‐RDN, 21±1; Sham, 19±2 ml) or sodium balance (RF‐RDN, 0.59±0.04; Sham, 0.48±0.06 mEq), or urinary angiotensinogen, protein and creatinine excretion rates. At the end of week 2, kidney norepinephrine levels in RF‐RDN rats (left, 0±0; right, 10±10 ng/g kidney) were markedly decreased compared with levels from sham SHR (left, 130±10; right, 110±10 ng/g kidney). Conclusions These data demonstrate that in hypertensive SHR, bilateral RF‐RDN produces an increase in urinary sodium excretion, which may potentially contribute to the concurrent decrease in BP.Grant Funding Source: Biosense Webster IIS‐175 to DRK & FS; P30 GM103337 to LGN; P20 GM103514 to DRK

Dietary fatty acid profile: effects on caecal fermentation and performance of young and fattening rabbits

The present work was performed to study the effect of dietary inclusion of different fatty acid combinations (saturated, n-3 and n-6 polyunsaturated fatty acids; PUFA) on caecal fermentation activity, feed intake, growth rate and feed efficiency of young rabbits around weaning (17 to 44 d) and fattening rabbits (28 to 63 d of age). Five diets were formulated using the same raw materials and including 3% of lard (A diet, rich in saturated fat), sunflower oil (S diet, rich in n-6 PUFA), linseed oil (L diet, rich in n-3 PUFA), sunflower oil and lard at 1:1 rate (SA diet), or linseed oil and lard at 1:1 rate (LA diet). In the first trial, the effect of the 5 diets on rabbit performance was evaluated in a fattening period from 28 to 63 d of age, with 490 rabbits allocated in individual cages; mortality rates were measured with 1670 rabbits (750 allocated in individual cages and 920 in collective cages, 8 rabbits/cage). In the second trial, 120 young rabbits were used from 17 to 44 d of age, weaned at 28 d, allocated in collective cages and randomly fed with A, S or L diets, evaluating performance and gut weight and caecum fermentation activity. The use of animal fat or vegetable oil and the richness in n-3 or n-6 PUFA of vegetable oils had no significant effect on the feed intake (130 g dry matter/d) and growth rate of fattening rabbits (45.5 g/d), but the inclusion of sunflower oil in diet improved feed conversion rate (2.79 for S diet vs. 2.87 for the rest of diets; P<0.01). Mortality rate was lower when vegetable oils were included in diet (34 and 37% for S and L diets respectively vs. 45% for A diet; P<0.05). Feed intake and growth rate increased quickly from 17 to 44 d, but only small occasional differences were recorded in growth rate of young rabbits, in favour of rabbits receiving animal fat from 17 to 21 d (P<0.05) or sunflower oil from 28 to 30 d (P<0.05). Caecal traits of rabbits at 30 and 44 d of age were similar for the different dietary groups, although butyric acid concentration in caecum content at 44 d was the lowest (P<0.05) with L diet.

Effects on performance of ground wheat with or without insoluble fiber or whole wheat in sequential feeding for laying hens

Sequential feeding (SF) is an innovative system for laying hens consisting of nutrients separating energy, protein, and calcium supplies to fulfill nutrient requirements at the relevant time of day. In previous studies, hens received whole wheat in the morning and a balancer diet (rich in protein and calcium) in the afternoon. To improve SF utilization, the aim was to substitute whole wheat in the morning by an alternative energy supply: ground wheat and ground corn, with or without a proportion of whole wheat and insoluble fiber. The goal was to obtain the advantages observed in previous experiments with whole wheat [bigger gizzard, thinner hens, reduced feed conversion ratio (FCR)]. Four hundred thirty-two ISA Brown hens were housed in collective cages from 20 to 35 wk of age divided into 8 different treatments: a continuous control diet, a sequential diet with whole wheat in the morning, 3 wheat-based diets (ground wheat, ground wheat and 20% whole wheat, and ground wheat with 5% insoluble fiber) and 3 ground corn-based (ground corn, ground corn and 20% whole wheat, and ground corn with 5% insoluble fiber) provided in the morning. All sequential regimens received the same balancer diet rich in protein and calcium in the afternoon. Whole wheat SF gave the best results with an improved FCR compared with continuous control and all other SF diets. Wheat- and corn-based diets showed intermediate results between whole wheat SF and continuous feeding. Gizzard weight was higher and hens were lighter than with conventional continuous feeding, leading to an average FCR improvement of 3.2% compared with a continuous control. Thus, it is possible in SF diets to substitute, at least partially, whole wheat by ground wheat or ground corn with added insoluble fiber or some whole wheat, allowing more flexibility and economic optimization.

High sulfur content in corn dried distillers grains with solubles protects against oxidized lipids by increasing sulfur-containing antioxidants in nursery pigs1

Some sources of corn dried distillers grains with solubles (DDGS) contain relatively high amounts of oxidized lipids produced from PUFA peroxidation during the production process. These oxidized lipids may impair metabolic oxidation status of pigs. The objective of this study was to understand the effects of feeding corn-soybean meal diets (CON) or diets containing 30% highly oxidized DDGS with 1 of 3 levels of supplemental vitamin E (dl-α-tocopheryl acetate), none, the 1998 NRC level (11 IU/kg), and 10x the 1998 NRC level (110 IU/kg), on oxidative status of nursery pigs. The DDGS source used in this study contained the greatest thiobarbituric acid reactive substances (TBARS) value, peroxide value, and total S content (5.2 ng/mg oil, 84.1 mEq/kg oil, and 0.95%, respectively) relative to 30 other DDGS sources sampled (mean values = 1.8 ng/mg oil, 11.5 mEq/kg oil, and 0.50%, respectively). Barrows (n = 54) were housed in pens and fed the experimental diets for 8 wk after weaning and transferred to individual metabolism cages for collection of feces, urine, blood, and liver samples. Total S content was greater in DDGS diets than in CON (0.39 vs. 0.19%). Dietary inclusion of 30% DDGS improved apparent total tract digestibility of S (86.8 vs. 84.6%; P < 0.001) and S retained (2.94 vs. 2.07 g/d; P < 0.01) compared with CON. Although pigs were fed highly oxidized DDGS in this study, serum TBARS were similar between DDGS and CON treatments. There was an interaction between DDGS and dietary vitamin E level for serum concentrations of α-tocopherol. Serum α-tocopherol concentrations were greater (P < 0.001) in pigs fed DDGS diets than those fed CON when dl-α-tocopheryl acetate was not provided or provided at the NRC level but were similar when dl-α-tocopheryl acetate was supplemented at the 10x NRC level. Pigs fed DDGS diets had greater serum concentrations of S-containing AA, particularly Met (P < 0.001) and taurine (P = 0.002), compared with those fed CON. Liver glutathione concentration was greater in pigs fed DDGS diets than CON (56.3 vs. 41.8 nmol/g). Dietary inclusion of DDGS (P < 0.001) and vitamin E (P = 0.03) increased enzyme activity of glutathione peroxidase. The elevated concentrations of S-containing antioxidants (Met, taurine, and glutathione) in vivo may protect pigs against oxidative stress when feeding highly oxidized DDGS. Therefore, the increased S content in DDGS may be beneficial, and increasing concentrations of vitamin E in diets may not be necessary to protect pigs against metabolic oxidative stress when feeding high S and highly peroxidized DDGS.

Effect of dietary fiber and genetic strain on the performance and energy balance of broiler chickens

The experiment was conducted to evaluate the effect of dietary fiber on the performance and energy balance of broiler chickens of a fast-growing strain (Cobb500) and a slow-growing strain (Label Rokens during the period of 1 one to 42 days of used In total, 360 male broilers (240 fast-grorain and 120 slow-grtrain)were, housed in collective cages. A completely randomized experimental dewith in a 3x2 factorial arrangement was applied, consisting of three groups of birds (slow-growing - SG; fast-growing fed ad libitum - FGAL; and fast-growing pair-fed with SG broilers - FGPF) and two iso-protein dis (a 3100 kcal ME/kg low-fiber diet and a 2800 kcal ME/kg high-fiber diet- Hwith containing 14% wheat bran and 4% oat hulls). Dietary fiber level did not affect feed intake (FI); however, it resulted in lower weight gain (WG) and worse feed conversion ratio (FCR) (p < 0.001) in birds fed the HFD diet due to its lower energy content. The FGPF group presented higher WG than SG and better FCR (p < 0.001), indicating that fast-growing birds present better performance than SG broilers, even under restricted feed intake. The SG group retained more energy relative to body weight (p < 0.001), which is associated to higher body fat retention in this strain (p < 0.001). The slow-growing strain did not present better use of high-fiber diet than fast-growing strain as expected.

Housing of growing rabbits in individual, bicellular and collective cages: growth performance, carcass traits and meat quality

During growth (from 27 to 75 days of age), 384 rabbits were kept in different types of wire-net cages: 72 individual cages (72 rabbits; 10 animals/m2), 48 bicellular cages (96 rabbits; 2 rabbits/cage; 18 animals/m2) and 24 collective cages (216 rabbits; 9 rabbits/cage; 18 animals/m2). The rabbits housed in individual cages showed higher daily weight gain both during the fattening period (from 52 to 75 days of age) and during the whole period of growth (43.0 v. 41.8 and 41.5 g/day; P < 0.05), and they had a higher final live weight at 75 days of age (2678 v. 2619 and 2602 g; P < 0.05) compared with the rabbits in the bicellular and collective cages, respectively. Rabbits in individual cages ingested more feed (133 v. 127 and 126 g/day; P < 0.01), but the feed conversion did not differ significantly among rabbits housed in the three types of cages. At slaughter, the carcass traits and meat quality were weakly affected by the housing system. The transport losses were higher in rabbits kept in individual and bicellular cages compared with those reared in collective cages (3.1% and 2.9% v. 2.2%; P < 0.01). In rabbits kept in individual cages, the hind leg muscle to bone ratio was higher (6.35 v. 6.19 and 5.91; P < 0.05) compared with the bicellular and collective cages, respectively. The pH and colour of the longissimus lumborum did not change with the housing system, while the b* index of the biceps femoris was lower (3.04 and 3.32 v. 4.26; P < 0.001) in the rabbits kept in individual and bicellular cages, respectively, than in those kept in collective cages. In conclusion, the rabbits housed in individual cages showed higher daily growth than rabbits kept in bicellular or collective cages, but they had a similar feed conversion and carcass quality. Differently, neither in vivo performance nor slaughter results differed among the rabbits kept in bicellular cages or in collective cages. The meat colour may be affected by the housing system, but to an extent that is hardly perceivable by the final consumer.

Housing of growing rabbits in individual, bicellular and collective cages: fear level and behavioural patterns

During growth (27 to 75 days of age), a total of 384 rabbits were kept in 72 individual cages, 48 bicellular cages (2 rabbits/cage) and 24 collective cages (9 rabbits/cage). To evaluate the effects of the housing system on the fear level and behavioural patterns of rabbits at the two ages (39 to 45 days and 66 to 73 days), a tonic immobility test and an open-field test were conducted and their behaviour was video recorded. In the tonic immobility test, the number of attempts to induce immobility (1.38) was lower, and the duration of immobility (47.8 s) was higher (0.05 <P < 0.01) in the rabbits housed in individual cages than in those kept in bicellular (1.72 attempts and 25.0 s of immobility) and collective cages (1.99 attempts and 25.0 s of immobility). During the open-field test, the rabbits from individual and bicellular cages showed higher latency (38.8 and 40.3 v. 27.0 s), a lower number of total (73.3 and 81.7 v. 91.9) and central displacements (3.6 and 2.8 v. 5.4) and a shorter running time (11.8 and 13.6 s v. 17.7 s) and the time biting the pen (5.5 and 9.1 s v. 28.2 s) compared with the rabbits kept in collective cages (0.05 <P < 0.001). During the 24-h video recording, the rabbits in individual and bicellular cages spent less time allogrooming (0.34% and 0.19% v. 1.44%), moving (0.74% and 0.60% v. 1.32%) and running (0.08% and 0.03% v. 0.21%) than the rabbits in the collective cages (0.01 <P < 0.001). The lowest numbers of alerts and hops were observed in the rabbits kept in bicellular cages. With increasing age, a lower number of rabbits were sensitive to the immobility test and more rabbits entered the pen spontaneously during the open-field test (P < 0.001). In conclusion, the rabbits in individual cages exhibited the highest fear level and incomplete behavioural patterns; the rabbits housed in collective cages showed the lowest fear levels and had the possibility of expressing a wider range of behaviour; and the rabbits in bicellular cages exhibited an inconsistent pattern of fear in the tonic immobility and open-field tests. Probably, these rabbits were in a less stressful condition compared with animals in individual cages because social contacts were allowed, even if freedom of movement was more limited.

Arsenic urinary speciation in Mthfr deficient mice injected with sodium arsenate

In most mammalian species, arsenic biotransformation occurs primarily by biomethylation and reduction reactions, with dimethylarsinic acid being the predominant metabolite excreted in the urine. Methylenetetrahydrofolate reductase (Mthfr) plays a key role in folate metabolism by channeling one-carbon units between nucleotide synthesis and methylation reactions. In the study on transgenic Mtfhr knockout mice we investigated: (1) whether Mthfr is an important determinant in arsenic biotransformation by performing urinary arsenic speciation, and (2) whether dietary folate deficiency alters arsenic biotransformation in these mice. The Mthfr mice fed folate replete or folate deficient diet were injected with sodium arsenate 1mg/kg, and placed in metabolic cages for a urine collection. The urine was analyzed for arsenic species. Additionally, folate and homocysteine plasma level was analyzed in Mthfr mice. When fed a folate control diet, the Mthfr−/− mice excreted significantly less of the total arsenic in urine than did the Mthfr+/+ and Mthfr+/− mice. The Mthfr−/− had significantly lower levels of pentavalent arsenic in their urine than did the Mthfr+/+mice. The wild type mice excreted significantly less pentavalent arsenic when they were fed folate deficient diet comparing to control diet. The current data suggest that both the Mthfr status and food folate level modulate in a significant manner excretion of arsenic in mice, following intraperitoneal administration of sodium arsenate.

Effects of melatonin on ovarian follicles

To evaluate the histomorphometry and expression of Ki-67 and c-kit in ovarian follicles of pinealectomized or melatonin-treated pinealectomized rats. Forty adult rats were randomly divided into four groups of 10 animals: Group I - control; Group II - sham-pinealectomized; Group III - pinealectomized (Px), and Group IV - Px treated with melatonin (10μg/night, per animal). After two months' treatment, on the night of proestrous, the animals were placed in metabolic cages for night urine collection and subsequent measurement of 6-sulfatoxymelatonin (6-SMT). The rats were anesthetized, blood samples were taken for estrogen and progesterone determinations, and they were then euthanized. The ovaries were dissected out for further histological and immunohistochemical analyses. Data were first submitted to analysis of variance (ANOVA) complemented with the Tukey-Kramer test for multiple comparisons (P<0.05). The urinary levels of 6-SMT and serum progesterone were lower in the Px group (GIII). Exogenous melatonin treatment restored both blood melatonin and 6-SMT urinary levels. The histomorphometric data in Group III revealed a significant increase of degenerating antral and non-antral follicles with regard to the other groups. In addition no corpora lutea were observed in this group. No significant differences were noticed regarding the number of corpora lutea among the other groups (I, II and IV), but the number of cells and the thickness of the theca interna of Px animals (Group III) were higher than in the other groups. Conversely, the density of progesterone receptors (fmol/g) in the ovaries of Group III was significantly lower than in the other groups. Our data indicate that melatonin exerts a role on the maintenance of a proper follicular function, and is thus important for ovulation and progesterone production.

Influence of in ovo prebiotic and synbiotic administration on meat quality of broiler chickens

A trial was conducted to evaluate the effect of in ovo injection of prebiotic and synbiotics on growth performance, meat quality traits (cholesterol content, intramuscular collagen properties, fiber measurements), and the presence of histopathological changes in the pectoral muscle (PS) of broiler chickens. On d 12 of incubation, 480 eggs were randomly divided into 5 experimental groups treated with different bioactives, in ovo injected: C, control with physiological saline; T1 with 1.9 mg of raffinose family oligosaccharides; T2 and T3 with 1.9 mg of raffinose family oligosaccharides enriched with different probiotic bacteria, specifically 1,000 cfu of Lactococcus lactis ssp. lactis SL1 and Lactococcus lactis ssp. cremoris IBB SC1, respectively; T4 with commercially available synbiotic Duolac, containing 500 cfu of both Lactobacillus acidophilus and Streptococcus faecium with the addition of lactose (0.001 mg/embryo). Among the hatched chickens, 60 males were randomly chosen (12 birds for each group) and were grown to 42 d in collective cages (n = 3 birds in each 4 cages: replications for experimental groups). Broilers were fed ad libitum commercial diets according to age. In ovo prebiotic and synbiotic administration had a low effect on investigated traits, but depend on the kind of bioactives administered. Commercial synbiotic treatment (T4) reduced carcass yield percentage, and the feed conversion ratio was higher in T3 and T4 groups compared with other groups. The abdominal fat, the ultimate pH, and cholesterol of the PS were not affected by treatment. Broiler chickens of the treated groups with both slightly greater PS and fiber diameter had a significantly lower amount of collagen. The greater thickness of muscle fibers (not significant) and the lower fiber density (statistically significant), observed in treated birds in comparison with those of the C group, are not associated with histopathological changes in the PS of broilers. The incidence of histopathological changes in broiler chickens from examined groups was low, which did not affect the deterioration of meat quality obtained from these birds.

Collective translational motions and cage relaxations in molecular ionic liquids.

In this computational study, the collective translational motions of 1-ethyl-3-methylimidazolium triflate, characterized by its current correlation function and its collective dipolar displacement, are interpreted in terms of an ion cage around a central ion. Thereby, a coincidence of the relevant time constants is observed. Furthermore, the ion cage is long living and its composition is rather heterogeneous. Besides high numbers of counter ions, several ions of like charge populate the first shell around a central ion. In contrast to the strong influence of the local environment on the collective translational motion, rotations are strictly collective. In other words, a local picture falls short of describing the overall antiparallel alignment of ionic dipoles. A further issue of this work is the interpretation of the initial region of the collective dipolar displacement. It can be related to all collective translational processes showing up in the computational dielectric spectrum. In particular, slow translational processes which are invisible in the current correlation function can be detected. The inclusion of these slow processes allow for an excellent computational reconstruction of the experimental spectrum of the generalized dielectric constant.

Behavioral analysis of Wistar rats fed with a flaxseed based diet added to an environmental enrichment.

Flaxseed has a high content of n-3 fatty acids and its intake associated with an environmental enrichment may promote distinct behavioral results upon habituation and animal behavior. This work aimed to evaluating animal behavior under the use of these two tools in the Open Field Test. Thirty-six male Wistar rats were divided into 6 groups (n = 6): FEEG, receiving chow made up of flaxseed and kept in enriched environment; FSEG, receiving flaxseed based diet and kept in a standard environment; CEEG, receiving casein based diet and kept in enriched environment; CSEG, receiving casein based chow and kept in standard environment; MCEEG, receiving chow made up of casein but modified so as to provide the same content of fibers and lipids found in flaxseed diet and kept in enriched environment; MCSEG, receiving modified casein based diet and kept in standard environment. All animals were kept under controlled temperature, collective cages and dark/light cycle, receiving chow and water ad libitum, except for MCEEG and MCSEG, which were pair fed with FEEG and FSEG, respectively. Chow intake and animal body weight were evaluated twice in a week. Animals were maintained in these groups from the first until the second month of life, by the time when 3 day tests in Open Field Test began. Finishing the tests, animals were sacrificed and their brains were obtained in order to calculate the relative brain weight. Our results show an interplay between flaxseed and environmental enrichment in habituation to a new environment, making the animals more manageable and less stressed.

Effect of density and group composition on the performance of fattening rabbits

Intensive rabbit breeding normally involves the use of small collective cages housing from 2 to 8 rabbits according to the surface area of the cage. Average density normally lies between 15 and 18 rabbits/m2. Increased interest in safeguarding animal welfare in livestock farming and the need to reduce intensive rabbit production costs have led in recent years to studying alternative housing to the classic cage. In this context, rabbit breeding in colonies could represent an interesting alternative to the classic cage. Colonial breeding and greater space availability appear to better satisfy the behavioural needs of rabbits and their welfare (Ferrante et al., 1997). In terms of production, however, the results appear discordant...

Novel therapy approach in primary stroke prevention: simultaneous inhibition of endothelin converting enzyme and neutral endopeptidase in spontaneously hypertensive, stroke-prone rats improves survival

<title/>Objectives: Stroke, frequently a consequence of hypertension, is one of the leading causes of death and neurological disabilities worldwide. In the ischemic brain, levels of endothelin-1, one of the most potent vasoconstrictors, are raised. Anti-inflammatory and neuroprotective effects of endothelin antagonists after stroke have been described in literature. Based on these findings, we investigated the protective effect of the endothelin converting enzyme/neutral endopeptidase blocker, SLV 338, in salt-loaded, stroke-prone, spontaneously hypertensive rats.Methods: Male, 8-week-old spontaneously hypertensive stroke-prone rats were put on a high salt diet and treated with either 30 mg/kg or 100 mg/kg SLV 338 or vehicle for 27 weeks. Blood pressure, neurological outcome, body weight, and mortality were investigated throughout treatment. In weeks 1 and 9, animals were housed in metabolic cages for collection of urinary and blood samples and assessment of salt water and food intake. In weeks 22 and 27, additional blood samples were taken. At the end of the study, all brains were analyzed using magnetic resonance imaging.Results: SLV 338 was well tolerated in all animals. Neurological outcome and infarct size were similar in all groups. Albuminuria was considerably delayed and the incidence of stroke significantly lowered in treated animals. In spontaneously hypertensive stroke-prone rats, treatment with SLV 338 significantly (P = 0·01) improved survival in comparison to the vehicle treated group in a blood pressure-independent manner.Discussion: Our data in spontaneously hypertensive stroke-prone rats demonstrate that combined endothelin converting enzyme/neutral endopeptidase inhibition could offer a new therapeutic approach for primary stroke prevention and improvement of mortality. The mechanism seems to be blood pressure-independent.

Potential use of Ceratitis Capitata exhausted diets in growing rabbit diets.

An in vivo digestibility trial and a fattening trial were carried out to evaluate the potential dietary use of a dehydrated Ceratitis capitata exhausted diet (CED) on growing rabbits. For the digestibility trial, 2 pelleted diets were manufactured including 0 and 50% of dry matter (DM), excluding the premix, from CED (CED0 and CED50 diets, respectively), using 10 three-way crossbred rabbits of 42 days of age per diet. For the fattening trial, 3 almost iso-energetic, iso-protein and iso-fibrous pelleted diets were manufactured including 0, 15 and 30% of DM from CED (CED0, CED15 and CED30 diets, respectively), and offered to 180 weaned rabbits (60 per experimental diet) randomly housed in collective cages (5 animals per cage). Health status and performance traits were monitored from 28 to 58 days of age. CED was characterised by high water content (51%), but its DM was rich in fibre (15% ADF), high-digestible carbohydrates (27% of soluble sugars) and protein (17% of CP). The lysine (0.94% DM) and methionine (0.93% DM) contents of CED were similar to those observed for some common vegetal protein concentrates, but cysteine content was low (0.26% DM). The dietary inclusion of CED at 50% increased DM, organic matter and gross energy apparent digestibility coefficients (approx. +8%; P

The European experience in poultry welfare—A decade ahead

Farm animal welfare is a major issue in Europe, which resulted in regulations and development of research dedicated to animal welfare, especially on standard poultry production, which is often considered as resulting in very poor welfare. The effect of selection is also often questioned. Indeed, capacities of adaptation have been very little considered during the first years of commercial selection and thus have been reduced. Nowadays, a much greater importance is given to welfare-related traits and genomic selection should alleviate the need for their measurements in the short-term. However, the choice of the fittest selection criteria is still to be made. Because behavioral traits are highly dependent on environment, general reactivity may be more efficient. For example, selection against undesirable behavior such as feather pecking has been proven to be efficient, but selection for reduced mortality rates in collective cages proved to be preferable. Most often, selection should not exacerbate extreme values, which are most often detrimental, as in the case of social motivation, which, when increased to too large of an extent, results in increased aggressivity. Moreover, a general propensity will not result in overall improvement; for example, reducing fearfulness has positive effects but does not modify response to social stress. Detrimental effects on other traits may also be observed: although genetic resistance to diseases should increase animal welfare, it may also result in increased frequency of silent carriers and in turn to human transmission. Indeed, an optimum must be found. Studying lines selected for or against these traits will be of great help to choose the best strategy of selection. Another and longer term concern should be on links with other production traits but also on sustainability, which will probably be of greater importance in the coming years.

Effects of sildenafil on maternal hemodynamics and fetal growth in normal rat pregnancy.

It has been suggested that the phosphodiesterase-5 (PDE5) inhibitor sildenafil may be useful in the treatment of hypertension during pregnancy. However, we have reported a selective increase in renal inner medullary PDE5 that participates in the sodium retention of pregnancy. Therefore, the purpose of this study was to determine whether oral sildenafil treatment impairs maternal plasma volume expansion and/or fetal growth during rat pregnancy. Rats received sildenafil (10 mg x kg(-1) x day(-1), 50 mg x kg(-1) x day(-1), or 90 mg x kg(-1) x day(-1)) or vehicle on days 4-20 of pregnancy. On days 14-19, rats were housed in metabolic cages for collection of urine and measurement of food and water intake. Terminal hemodynamic and fetal measurements were taken on day 20. None of the sildenafil doses lowered blood pressure, and although all doses increased plasma cGMP concentrations, only the highest dose increased aortic and inner medullary cGMP content. Sildenafil had no effect on maternal weight gain; however, the highest dose decreased both plasma volume and renal sodium retention. The pup number and size were similar among the groups. Therefore, these studies suggest that low doses of systemic sildenafil may be safe during pregnancy in the rat, but higher doses may interfere with the physiological sodium retention and volume expansion of pregnancy. The effects of systemic sildenafil on blood pressure and sodium retention during hypertension in human pregnancy remain to be examined.

Effect of different rearing systems and pre-kindling handling on behaviour and performance of rabbit does

The aim of this study was to ascertain how collective cage and pre-kindling handling (training does to go into their own nest) practices, in comparison to standard housing (single cage rearing), modify the behaviour and the performance of rabbit does. To this aim, 40 nulliparous New Zealand White does were artificially inseminated, where the pregnant ones were assigned to three groups with the following treatments: eight does, kept in single standard cages (group S); eight does kept in two colony cages and trained to recognise their own nest (group TC); eight does kept in two colony cages, but not trained to recognise their own nest (group UC). Performance and behaviour, with particular attention to the social relationships of animals, were evaluated for one year. The housing system and training practice affected the behaviour of animals. Does kept in colony cages showed a wider behavioural repertoire, as well as fewer stereotyped and social behaviours. However, the interactions between animals were not always friendly; in particular, the UC group showed the highest incidence of aggressiveness: attack (26.61% vs. 13.55%) and dominance (12.98% vs. 8.81%) and lower allo-grooming (4.16% vs. 19.56%) in comparison to TC does. Negative correlation values between feeding and moving behaviours were obtained (−0.37 and −0.28) for TC and UC does, respectively. UC does showed significant correlation coefficients between stereotyped, moving and static behaviours (0.50 and −0.61, respectively). Different correlation values between moving and social interactions were shown for TC (−0.44) and UC does (0.48). In UC does, stereotypies were also correlated with social relationships (0.40) and, in particular, with attack (0.57; data not shown). Smelling one other was one of the major social activities, but while animals in the UC group exhibited a stable trend in the days close to kindling, in the TC group, the values increased from 20% (3 days before partum ) to 75% (3 days after partum ). Dominant and submissive features in TC does showed the same trends and decreased to about 0% after kindling; in contrast, in the UC group, dominant behaviours were performed even after kindling (4.8%) and submissiveness reached values similar to that of the first day of observation (about 35%). Reproductive performance and productivity of colony does were lower than S does. This reduction was lessened if does were trained to recognise their own nest. In the UC group, does had very low sexual receptivity (49.8%) and fertility rates (40.8%), a higher annual replacement of does (83.3%) and low rabbits sold/year/doe (17.7), probably due to the higher social pressure and aggressiveness, as confirmed by the percentage of does replaced due to severe injury (8.3%). In conclusion, breeding does in a colony cage, without the training to recognise their own nest, renders the animals disagreeable to social encounters, does not assure adequate welfare or a productive performance and increases the possibility of suffering from injuries caused by attacks from other does.

Efeito da suplementação dietética de arginina na cicatrização das anastomoses colônicas em ratos

RACIONAL: A arginina, aminoácido condicionalmente essencial, participa de diversos processos fisiológicos, em particular na cicatrização e na função imune. OBJETIVO: Avaliar o efeito da suplementação por via oral da arginina na cicatrização colônica em ratos. MÉTODO: Foram utilizados 47 ratos Wistar machos, adultos, com peso médio de 345,45 ± 8,35g, alocados em gaiolas coletivas em grupos cinco ou seis animais. Todos receberam água e ração ad libitum, pesados a cada dois dias e randomizados para receberem por gavagem suplementação com arginina a 10% (grupo ARG) ou solução de aminoácidos a 10% (grupo AA) de forma isovolumétrica, isocalórica e isonitrogenada (1,5 g/kg/dia) por sete dias antes do procedimento operatório e quatro após. Um terceiro grupo recebeu solução salina isotônica (grupo SSI), isovolumetricamente. Os ratos foram submetidos a duas colônicas término-terminais confeccionadas 3 cm distais à válvula ileocecal e outra 5 cm distais à primeira, em plano único com fio monofilamentar de nylon 5-0, e foram sacrificados no 5º dia de pós-operatório Neste dia, as duas anastomoses foram ressecadas, sendo uma conservada em solução salina para medidas de tração e a outra enviada à anatomia patológica, para análise do colágeno (total, maduro e imaturo), e imunoistoquímica para a pesquisa de miofibroblastos e neovascularização. Foi avaliado o peso corpóreo ao longo do experimento. A análise estatística foi realizada com os testes t de Student e de Mann-Whitney. RESULTADOS: A comparação referente ao peso nos três grupos não evidenciou diferença significativa nos pesos iniciais, mas foi observada diferença entre os finais nos grupos SSI e AA (324,7g vs. 298g, P=0,04). A tensão foi significativamente maior no grupo AA quando comparado ao grupo SSI (0,94kgf/cm² vs 0,67 kgf/cm², P=0,04), mas não em relação ao grupo ARG (0,94kgf/cm² vs 0,70 kgf/cm², P=0,09). Quanto à força máxima de tração observou-se diferença significativa entre o grupo AA e o grupo SSI (0,18kgf vs 0,13 kgf, P=0,04) mas não em relação ao grupo ARG (0,18kgf vs 0,14 kgf, P=0,08). A força de ruptura total evidenciou valor significativamente maior para o grupo AA quando comparado ao grupo ARG (0,10kgf vs 0,06 kgf, P=0,05), mas não em relação ao grupo SSI (0,10kgf vs 0,09 kgf, P=0,54). Não foi observada diferença significativa quanto à concentração dos colágenos subtipo I e III e nem do índice de maturação de colágeno nos três grupos. Não foi observada também diferença significativa em relação à contagem de vasos sanguíneos ou miofibroblastos pela imunoistoquímica entre os três grupos. CONCLUSÃO: A administração de solução contendo 20 aminoácidos se mostrou mais efetiva do que a administração isolada de arginina nas provas de tração das anastomoses colônicas.