Metabolic adaptations in neonatal mother-deprived rabbits

[EN] In order to study the metabolic adaptation in response to 48 h transient doe-litter separation (DLS) in young rabbits (5 rabbits/d group) between postnatal 9 and 11 d, plasma concentrations of thyroid hormones T3 and T4, insulin, leptin, glucose, triglycerides (TG), and free fatty acids (FFA) were examined before (6-8 d), during (9-11 d), and after separation (12-16 d). T3 concentrations in newborn control rabbits gradually increased from 0.6 ng/mL at postnatal 6 d to 1.0 ng/mL at postnatal 16 d, whereas those of T4 remained fairly constant (25 ng/mL) up to postnatal 14 d, when T4 gradually declined to 8 ng/mL. T3 values of DLS newborn rabbits did not differ from those of controls at postnatal 10 and 11 d, but were lower (P<0.05) at postnatal 12 d, while T4 concentrations in DLS animals increased, although not significantly, between postnatal 10 and 12 d compared to controls. Insulin concentrations in young control rabbits ranged between 0.6 and 1.0 mg/L in the early postnatal days, whereas those for leptin averaged 2-3 ng/mL. Insulin and leptin values in DLS newborn rabbits were lower (P<0.05) at postnatal 10 and 11 d, but thereafter rebounded to levels close to those of controls. Glycaemia showed a comparable trend in both groups, ranging between 170 and 190 mg/dL up to postnatal 14 d, but thereafter decreased (P<0.05) to values of 120-130 mg/dL independently of treatment. Concentrations of TG varied greatly from day to day around a mean value of 300 mg/dL, whereas those of FFA remained at approximately the same steady-state levels from postnatal 6 to 16 d, averaging 0.8 mM without any significant differences between groups. In conclusion, these findings confirm that newborn rabbits can cope with the metabolic stress of starvation associated with DLS by lowering insulin and leptin concentrations while maintaining those of thyroid hormones, an overall endocrine response which, together with temporary increase of glucorticoids, successfully maintains an adequate energy balance.This work was partially supported by a grant from the Italian “Ministero Istruzione Università e Ricerca” (Progetto Ricerca Interesse Nazionale – Prot. 2001072484 and 2003074002) and by generous donations from the BC Red-water Trust (Perugia, Italy). Procedures conformed to animal care guidelines and were approved by the Bioethical Committee of the University of Perugia in accordance with the current laws of Italy. The authors gratefully acknowledge the revision of the English text by Sheila Beatty.Brecchia, G.; Zerani, M.; Bonano, A.; Boiti, C. (2010). Metabolic adaptations in neonatal mother-deprived rabbits. World Rabbit Science. 18(4):229-236. doi:10.4995/wrs.2010.78022923618

The effect of the dietary electrolyte balance on the plasma energy, protein, mineral variables and endocrine profile of pluripare rabbit does

In this research, the effect of the electrolyte balance (dEB, dEB=Na+K-Cl) on the plasma energy, protein, enzyme, mineral profile and on the endocrine response of rabbit does was studied. The animals, belonging to the Grimaud genotype, were at the third reproductive cycle. The rabbits were allocated to reproductive cages and divided into two groups to be fed two diets with different electrolyte balances (dEB1=27 meq/100g and dEB2=35 meq/100g). The diets were similar in ingredients, protein (CP=19.81% d.m.) and energy content (DE=2945 kcal/kg d. m.), whereas they had different sodium content (dEB1=0.21% d.m. and dEB2=0.38% d. m.). The animals were fed the two diets from first mating (20 weeks of age) until the litter weaning of the third reproductive cycle. From the mating of the third cycle the environmental temperature averaged 15\ub0C and the relative humidity was about 79%. At about 39 weeks of age, five days after parturition, a blood sampling was performed on the does. Results pointed out that the two dEB levels did not significantly affect the body weight and feed intake of rabbit does. No significant dEB effect was observed on the main variables of plasma metabolic (glucose, triglycerides, cholesterol, total proteins, albumin and globulines), enzyme (aspartate-aminotransferase, alanine-aminotransferase, ?-glutamyl-transpeptidase), and mineral (Ca, P, K, Na, Cl) profile. The plasma concentration of 17 f-oestradiol was similar between the two groups. Cortisol plasma level slightly increased in dEB2 rabbits. Also the triiodothyronine (T3) and thyroxine (T4) were unaffected by the dietary dEB level as well as the free fractions (FT3 and FT4). The results point out that a prolonged administration of a diet with an electrolyte balance of 35 meq/100 g does not affect the metabolic and mineral profile nor the oestradiol plasma level but tendentially increases the thyroid hormones of pluripare lactating rabbit does when they are in neutral thermal conditions

A study on the reproductive performance and physiological response of rabbit bucks fed diets with two different mineral contents

The reproductive performance and the plasma biochemical profile of rabbit bucks relating to two dietary electrolyte balances (dEB, dEB=Na+K-Cl) were investigated. Two pelleted diets were fed the male rabbits from the first mating (50 weeks of age) until the weaning of the litters of the third reproductive cycle. The diets were similar in composition and were isoproteic (crude protein=19.81% d. m.) and isoenergetic (digestible energy=2945 kcal/kg d. m.); the sodium content was 0.21 an 0.38% d. m. and the electrolyte balance was 27 meq/100g and 35 meq/100 g in the dEB1 and dEB2 diets, respectively. The higher sodium level in the diet was obtained by increasing the mineral content in the supplement of the feed. Matings occurred with natural insemination. The trial started in the summer period under a hot climate but the third cycle presented neutral thermal hygrometric conditions (temperature=15\ub0C and relative humidity=79%). The photoperiod was 16L:8D. At the third cycle, at 70 weeks of age, the bucks were submitted to a blood sampling early in the morning. At the third reproductive cycle, the dEB2 diet did not significantly affect the body weight and the feed intake of the rabbits. The two experimental groups presented a similar number of kids born and born alive and number of kids/mating. Plasma glucose, triglycerides, cholesterol, total proteins, albumin and globulines resulted unaffected by the diets. The plasma enzyme activities (aspartate-aminotransferase, alanine-aminotransferase, \u3b3-glutamyltranspeptidase) and the mineral contents of calcium, phosphorus, potassium, sodium and chloride were similar between the groups. No significant difference was observed for plasma cortisol, even if the higher dEB level induced a tendential decrease in dEB1 group. T3 (thriiodothyronine), T4 (thyroxine) and FT3 (free T3) were similar between the groups. FT4 (freeT4) slightly increased in the dEB2 rabbits. Results indicate that using daily rations with an electrolyte balance ranging from 27 to 35 meq/100 g continuously for three reproductive cycles did not exert any effect on the reproductive performance of the bucks nor on the biochemical profile

Automation in 3D cellular system in Live-Imaging with Microfluidic Technology CELLviewer®

Differences observed when comparing cell cultures in 2D and 3D is morphological dissimilarity and their evolution over time. Cells grown in a monolayer tend to flatten on the bottom of the plate by adhering and spreading on the horizontal plane without expanding into the vertical dimension; § Mitochondria are involved in crucial cellular tasks controlling the cell cycle and growth such as cell signaling, differentiation, and death. Damage to and subsequent dysfunction of mitochondria play a role in various diseases like diabetes, myopathy and other systemic disorders; § CELLviewer® enables the simultaneous 3D cell culture and live cell imaging as well, featuring microfluidics and time-lapse multicolour epifluorescence microscopy; § Single cell tracking in 3D space is now possible and is combined with subsequent biochemical analyses of individually tracked cells, keeping their identity traceable with CELLviewer® system; q Jurkat (ATCC) Cells grown at 37°C and 5% CO2; q Medium RPMI 1640 soil (Gibco, Life Technologies, Thermo Fisher Scientific), with 2 mM of L-glutamine, 10% FBS, 100 units/mL of penicillin and 100 mg/mL of streptomycin; q MitoGreen (PromoKine, PromoCell) incubated for 20 minutes in the dark at 37°C with MitoGreen 200 mM; q The sample is then piped inside a 50ml Falcon tube closed with a 50ml CELLviewer® DOCK and flowed inside the cartridge chamber; q CELLviewer® automatically captures sample images in Brightfield channel and GFP channel; q ImageJ software was used for image analysis using the Measure function to calculate the diameter of a single cell; q 3D surface plot plug-in to display in 3D the distribution of the intensity of spatial fluorescence; Staining of mitochondria with fluorescent dyes, antibodies or fluorescent molecules can greatly facilitate studies of their function and distribution and the viability of cells in healthy and diseased individuals. The preliminary experience conducted with CELLviewer indicates that this equipment responds to the needs of individual operators as it consists of a synthesis of different integrated tools, which works both with manual and automated control. A microfluidic system has been developed and demonstrated that the 3D model can locate the 3D model spatially, it's possible to carry out experiments in direct time in terms of physiology, toxicology and clinical pharmacology. The entire automated system allows full autonomy and protocol management thanks to the software making the operator free to conduct other work, thus increasing the productivity of his project. In summary, the proposed microfluidic technology can serve as a new platform approach, which has the potential to advance studies at the cellular level. Single-cell Jurkat cells was isolated and imaged for 4 and 7 hours respectively and intensified labelling of the mitochondria and fluidic transport were observed over time. CELLviewer® can obtain detailed images of current cellular morphology with resolution and high-quality data; employing time-lapse imaging can be achieved, the evolution of cells and their 3D morphology

Performance and behaviour of rabbit does in a group-housing system with natural mating or artificial insemination

This study compared reproductive performance and behaviour of does raised in a group-housing system and in a regular cage system. The group-housing pen was divided into different functional areas for suckling, resting, and eating and special hiding areas for kits when they had left the nest-boxes and does to favour the species specific behavioural traits. Does had access to their nest-box by means of an individual Electronic Nest-box Recognition System (ENRS) activated by a coded transponder placed in their eartags. Eight does were housed in each pen. Natural mating (NM, with a buck in the group) or artificial inseminations (AI) were applied. Litter size, kit mortality and kit weight at 14 d of age were similar for group-housing and cages when NM were applied. With a natural reproduction rhythm group-housing led to an increase of +38% of litters. However, from a management point of view, a cycled production system with AI is preferred. With AI and group-housing, a lower kindling rate and a lower kit weight at weaning were found. The lower kindling rate was partly caused by pseudo-pregnancies that were found in 23% (P &lt; 0.01) of the does in the group-housing system against 0% in the control group. Sixteen to 20% of the does in the group-housing system had skin injuries, which is an indicator for aggression among does. Most of the injuries were seen on the body and most of them were superficial bites. Based on the results of this study, it can be concluded that group-housing of rabbit does seems possible, but more research is needed to solve the problems of the decreased kindling rate and occurrence of pseudo-pregnancies, the lower weight at weaning and aggressiveness among does

The different effects of linseed and fish oil supplemented diets on insulin sensitivity of rabbit does during pregnancy

This study investigates the effects of linseed (rich in ɑ-linolenic acid (ALA)) and fish oil (rich in eicosapentaenoic (EPA) and docosahexaenoic acid (DHA)) supplementation on the insulin resistance of pregnant rabbits. Two months before insemination, the rabbits (15 animals/group) were fed different diets: commercial standard (group C), supplemented with 10% extruded linseed (group L), and 3% fish oil (group FO). The L group does showed both the highest feed intake before AI (P &lt; 0.01) and the highest body weight (BW) throughout pregnancy (P &lt; 0.001). The L does yielded less milk than the C does (P &lt; 0.001); however, no differences were observed in either weight or size of litter at weaning. Regardless of diet, insulin concentrations and HOMA-IR values were higher during the first half of pregnancy (P &lt; 0.001). Nevertheless, the L does showed higher mean insulin concentrations than FO rabbits (P &lt; 0.01) and the lowest glucose clearance (P &lt; 0.01) during pregnancy. On the other hand, pregnant FO rabbits showed the lowest glucose concentrations (P &lt; 0.05) and the lowest Homeostasis model assessment values for insulin resistance (HOMA-IR, P &lt; 0.05) as well as a faster restoration of baseline glucose levels following glucose load (P &lt; 0.001). Before and during pregnancy, the BW of the rabbits was positively related to fasting sample- and tolerance test-derived indices of insulin resistance (P &lt; 0.05) suggesting that a high pre-pregnancy BW predisposes to gestational insulin resistance. Linseed supplementation increased BW and predisposed to insulin resistance during pregnancy; whereas, fish oil improved insulin sensitivity without significant changes in BW

Effect of the Growing Season, Trichoderma, and Clinoptilolite Application on Potentially Toxic Elements Uptake by Cucumis melo L

The extent to which different agricultural strategies may affect the uptake of potentially toxic elements (PTEs) by cropped plants is not entirely understood at a field scale. This study addresses the effect of seasonality, Trichoderma inoculation alone, or combined with different applications of commercial-grade clinoptilolite (i.e., foliar action, fertigation, and pellet) on the PTE content of early- and late-ripening cultivars of Cucumis melo L. Two similar field experiments were performed in spring and summer. For each cultivar/treatment combination, the input of PTEs [namely, chromium (Cr), copper (Cu), and lead (Pb)] into the soil-crop system through irrigation water, fertilizers, pesticides, and treatment products (i.e., Trichoderma and clinoptilolite products), as well as the PTE content of melon stem, leaves, and fruit, were measured through inductively coupled plasma-optic emission spectrometry (ICP-OES). Neither Trichoderma alone nor with clinoptilolite had a visible effect on PTE uptake by plants, whereas early season cultivation was strongly associated with reduced uptake of Cu and Pb. The high correlation of Cu and Pb content with stem and leaf calcium (Ca) content (used as a proxy for different transpiration rates under different growing seasons) indicated a possible uptake of these metals through Ca nonselective cation channels as a defense against drought stress. Reduced Cu and Pb concentrations were found in early-ripening fruit cultivated in spring. Concerning Cu and Pb risk management, in case of significant contamination in Mediterranean calcareous soils, early-ripening Cucumis melo L. cultivars are suggested instead of lateripening ones

Effect of LPS-induced inflammatory state on some aspects of reproductive function of rabbit does

Effetto dell\u2019infiammazione indotta con LPS su alcuni aspetti della funzione riproduttiva nelle coniglie. Scopo della ricerca \ue8 stato quello di studiare un modello d\u2019induzione sperimentale di infiammazione con lipopolisaccaridi (LPS) microbici nella coniglia fattrice e l'eventuale effetto sulla risalita degli spermatozoi. Due gruppi di 6 coniglie fattrici sono state inoculate per via intra-peritoneale rispettivamente con LPS di E. coli 0127:B8 (100 \ub5g/kg peso vivo), o con soluzione fisiologica (controllo). Sono stati rilevati per 72 ore temperatura rettale e il numero dei leucociti; dopo inseminazione artificiale \ue8 stata valutata la risalita degli spermatozoi nel tratto riproduttivo femminile e la situazione ovarica. L\u2019infiammazione sperimentale ha indotto un rilevante incremento della temperatura rettale e sostanziali modifiche a livello di leucociti che sono comunque scomparse entro 72 ore. Anche il numero di spermatozoi risaliti \ue8 stato significativamente pi\uf9 basso a livello di corna uterine e addirittura nullo a livello dell\u2019ovidutto. In conclusione si pu\uf2 affermare che \ue8 possibile costruire un modello d\u2019induzione dello stato infiammatorio nella coniglia mediante inoculazione intra-peritoneale di 100 \ub5g LPS/kg di peso vivo.The efficiency of the cycled production system in rabbit farms is greatly conditioned by the fertility rate of does. Nulliparous does generally exhibit high fertility rate (Castellini et al., 1998), whereas the reproductive performances of multiparous does goes down. One reason of this reduction is related to the use of intensive reproductive rhythms which implies an overlapping between lactation and insemination which often produces a severe energy deficit. As in other mammals, lactation shows a strong hormonal antagonism with the reproductive activity. An other cause of hypo-fertility depends on the sanitary condition of does. Genital tract inflammation and/or infection is one of the major causes of infertility (Gram et al., 2002) and often determined by incorrect practices of artificial insemination (AI). It has been demonstrated that uterine infection negatively affects fertility (Facchin et al., 1999) and prolongs the life span of corpora lutea (Boiti et al., 1999) due to uterine leukocytes infiltration, reduced prostaglandins synthesis and increased spermatozoa reabsorption. Lipopolysaccarides (LPS), constituents of the Gram-negative germ wall, are potent stimulators of prostaglandins synthesis and are widely used to simulate inflammation in several district and organs. The aim of the paper was to verify the effect of an LPS-induced inflammatory state on some aspects of reproductive function of non-lactating rabbit does

Impacts of trace element pollution on sewage sludge and soil-plant systems: developing remediation techniques and assessing plant uptake prevention measures

Trace Elements (TEs) pollution is a significant environmental concern due to its toxic effects on human and ecosystem health and its potential to bioaccumulate in the food chain and to threaten species survival, leading to a decline in biodiversity. Urban areas, industrial and mining activities, agricultural practices, all contribute to the release of TEs into the environment posing a significant risk to human health and ecosystems. Several techniques have been developed to control TEs into the environment. This work presents the findings of three-year PhD program that focused on research on TEs pollution. The study discusses three fundamental aspects related to this topic from the perspective of sustainable development, environmental and human health. (1) High levels of TEs contamination prevent the use of sewage sludge (SS) as a fertilizer in agriculture, despite its potential as a soil amendment. Developing effective techniques to manage TEs contamination in SS is critical to ensure its safe use in agriculture and promote resource efficiency through sludge reuse. Another purpose of the study was to evaluate different strategies to limit the TEs uptake by horticultural crops (specifically, Cucumis Melo L.). This study addressed the effect of seasonality, Trichoderma inoculation and clinoptilolite application on chromium (Cr), copper (Cu) and lead (Pb) content of early- and late-ripening cultivars of Cucumis Melo L.. Finally, the accumulation of copper and the effect of its bioavailable fraction on bacterial and fungal communities in the rhizosphere soil of two vineyards, featuring two different varieties of Vitis vinifera grown for varying lengths of time, were evaluated

Ovulation induction in rabbit does submitted to artificial insemination by adding lecirelin to the semen dose: preliminary results

The aim of this study was to analyze the effect of intravaginal administration of lecirelin on ovulation induction in rabbit does. Eighty pluriparous does (Martini genetic strain) were submitted to AI using a seminal dose of 0.5 ml containing about 10 million sperms. To stimulate ovulation, 4 homogeneous groups were submitted to different treatments: Control Group: 0.2 ml intramuscular administration of lecirelin (Dalmarelin, Fatro\uae); 0.2 Group: 0.2 ml intravaginal administration of lecirelin; 0.6 Group: 0.6 ml intravaginal administration of lecirelin; 2.0 Group: 2 ml intravaginal administration of lecirelin. In groups receiving an intra-vaginal administration, 25 \ub5g/ml Dalmarelin was diluted in the seminal dose using benzilic alcohol (20 mg/ml) as excipient. Blood samples were collected from all females, to determine LH prior (-60, -30 and 0 minutes) and (30, 60, 90, 120 and 180 minutes) after AI, and progesterone once a week for 4 weeks. After 7 days from AI, 10 does per group were euthanized in order to analyze the ovarian status. The does of control group showed a high LH peak after 30 minutes from AI; whereas intra-vaginal administration of 0.2 and 0.6 ml determined a lower increase of LH blood concentration after 2 hours. The highest dose did not produce any LH or progesterone increase. The ovary status showed a higher number of corpora lutea in Control group (P&lt;0.05), followed by 0.2 and 0.6 ones, whereas embryos were recorded only in Control and 0.2 groups. The unsuccessful of the other experimental groups could be ascribed to the negative effect of benzilic alcohol on seminal characteristic. Only 30% of 0.2 group does were pregnant and the prolificacy was 8 kits/doe. Compared to the control group, the progesterone concentration in pregnant does showed lower value in 0.2 group. In conclusion, in spite of the obtained results, it will be necessary to test different Dalmarelin formulations (lower volume, different excipient) to recommend the minimal dose to inject intravaginally for inducing ovulation