Letter from the Editor in Chief

Abstract not available.Pascual Amorós, JJ. (2007). Letter from the Editor in Chief. World Rabbit Science. 15(1). doi:10.4995/wrs.2007.612SWORD15

Letter from editor: World Rabbit Science website. Setting new standards in rabbit science

Pascual Amorós, JJ. (2008). Letter from editor: World Rabbit Science website. Setting new standards in rabbit science. World Rabbit Science. 16(4). doi:10.4995/wrs.2008.613SWORD16

Letter from the editor. World Rabbit Science at the 9th World Rabbit Congress and the Journal citation report

Pascual Amorós, JJ. (2010). Letter from the editor. World Rabbit Science at the 9th World Rabbit Congress and the Journal citation report. World Rabbit Science. 16(3). https://doi.org/10.4995/wrs.2008.910216

Letter from editor: Editorial Board changes and Journal Citation Report

Pascual Amorós, JJ. (2009). Letter from editor: Editorial Board changes and Journal Citation Report. World Rabbit Science. 17(3). doi:10.4995/wrs.2009.65011317

Long-term implications of feed energy source in different genetic types of reproductive rabbit females: III. Fitness and productivity

[EN] The specialization process associated with genetic selection could be associated with functional disorders, affecting the reproductive success of females (fitness). We hypothesized that by modulating energy acquisition and allocation of females we could balance productivity and reproductive success. To test this hypothesis, we used 203 rabbit females belonging to three genetic types: H (n=66) maternal line specialized in prolificacy, LP (n=67) generalist maternal line, R (n=70) paternal line specialized in growth rate. We fed each genetic type with two diets specifically designed to promote milk yield (AF) or body reserves recovery (CS). We controlled females between their first and fifth reproductive cycles, recording traits related with productivity and fitness of females. H females fed CS had on average 11.2 +/- 0.43 kits with an individual weight of 54 +/- 1.2 g at birth and 525 +/- 11 g at weaning. Their conception rate when multiparous was 44% and their survival rate at the end of the experiment 30%. When they were fed AF, the individual weight of kits was 3.8 g heavier (P<0.05) at birth and 38 g heavier at weaning (P<0.05), the conception rate when multiparous increased 23 percentage points (P<0.05) and the survival rate at the end of the experiment 25 percentage points (P<0.05). LP females fed CS had on average 10.8 +/- 0.43 kits with an individual weight of 52 +/- 1.2 g at birth and 578 +/- 11 g at weaning. Their conception rate when multiparous was 79% and their survival rate at the end of the experiment 75%. When they were fed AF, it only increased individual weight of kits at weaning (+39 g; P<0.05). R females fed CS had on average 8.4 +/- 0.43 kits with an individual weight of 60 +/- 1.2 g at birth and 568 +/- 11 g at weaning. Their conception rate when multiparous was 60% and their survival rate at the end of the experiment 37%. When they were fed AF, they presented 1.4 kits less at birth (P<0.05) but heavier at birth (+4.9 g; P<0.05) and at weaning (+37 g; P<0.05). Therefore, we observed that genetic types prioritized different fitness components and that diets could affected them. In this sense, seems that more specialized genetic types, were more sensitive to diets than the more generalist type.This study was supported by the Interministerial Commission for Science and Technology (CICYT) of the Spanish Government (AGL2014-53405-C2-1-P). The authors thank Juan Carlos Moreno for his technical support. Grants for Alberto Arnau from the Ministry of Economy and Finance (BES-2012-052345) are also gratefully acknowledged.Arnau-Bonachera, A.; Savietto, D.; Pascual Amorós, JJ. (2018). Long-term implications of feed energy source in different genetic types of reproductive rabbit females: III. Fitness and productivity. animal. 12(9):1886-1894. https://doi.org/10.1017/S1751731117003305S1886189412

Technical Note: Design of a large variable temperature chamber for heat stress studies in rabbits

[EN] One of the major constraint factors for rabbit production consists of the environmental conditions and especially high temperatures that negatively affect reproduction and growth performance. For this reason, several studies have addressed the effects of heat stress and possible solutions to alleviate its impact on rabbit performance. This article describes the design and operating features of a large temperature chamber (13x4.7x3.1 m) configured to house 42 rabbits. The probes consisted of temperature sensor model DS2438 and humidity sensor model HIH-5031. The system was controlled by an Arduino platform programmed by its Integrated Development Environment (IDE) software. The system takes a decision every minute: it connects the heating if the temperature is lower than programmed and connects exhaust fans if the temperature is over the programmed setting. To renew the indoor air, every 5 min the system switches off the heating and switches on the exhaust fans for 15 sec. Two experiments (with and without animals) were carried out to test the temperature control accuracy. Firstly, without animals, two tests were performed: (i) adjusting the temperature of the climatic chamber to the control house temperature plus 10ºC and (ii) based on daily minimum (32ºC) and maximum (37ºC) temperatures. Secondly, with animals, does were maintained (i) between a daily minimum (32ºC) and maximum (37ºC) for 48 h and (ii) between a daily minimum (25ºC) and maximum (35ºC) temperatures for 105 d. Mortality rates were noted in both tests. The results of comparing the measured temperature deviation from programmed temperature reported a coefficient of determination of 0.9850 and 0.9947, for plus 10ºC and 32-37ºC curves, respectively. In the animal tests, the determination coefficients were 0.9926 and 0.9928 for programmed curve in the range of 32 to 37ºC and 0.9859, 0.9900 and 0.9901 for programmed curve in the range of 25 to 35ºC. Survival of females in the temperature chamber was as expected for reproductive rabbit does: 100 and 82% in the 2 and 105 d trials, respectively. Results indicate that the chamber provided precise temperature control for the development of heat stress studies in rabbits.This work was supported by the Spanish Research Project (CICYT AGL2008-03274) and the Spanish "Ministry of Science and Innovation" HAR2010-21944-C02-01 and HAR2010-21944-C02-02.García Diego, FJ.; Pascual Amorós, JJ.; Marco Jiménez, F. (2011). Technical Note: Design of a large variable temperature chamber for heat stress studies in rabbits. World Rabbit Science. 19(4). https://doi.org/10.4995/wrs.2011.938SWORD19

Letter form de editor board: World rabbit science: towards an open access journal

Dear World Rabbit Science readers:World Rabbit Science's main aim has always been to provide universal access to scientifi cknowledge in the fi eld of cuniculture. From the outset, World Rabbit Science has engaged indifferent actions designed to achieve this goal.One example of this is the fact that since 2008, World Rabbit Science has published its contentsonline, allowing free access to all articles, reviews, conference abstracts... with the exception ofthe last two years, when they were only accessible by subscription. World Rabbit Science is alsofully accessible in many developing countries through the AGORA platform....Pascual Amorós, JJ.; Climent Navarro, AJ. (2011). Letter form de editor board: World rabbit science: towards an open access journal. World Rabbit Science. 19(2). doi:10.4995/wrs.2011.832SWORD19

Recommendations and guidelines for applied nutrition experiments in rabbits

[EN] The aim of this paper was to draw up a set of recommendations for applied nutrition and feeding trials with rabbits, in relation to certain aspects such as determining the nutritive value of raw materials or diets in growing or reproducing animals, studying digestive physiology and obtaining growth and reproduction parameters. We deal first with animals, size of the sample, housing conditions, diets, handling, measurements, and the data analyses relevant to the design of the experiment are described. Secondly, we give a list of recommended items and include some comments.This study was partly supported by the EUROPEAN COMMISSION (ERAFE program and the COST 848 Action).Fernández-Carmona, J.; Blas, E.; Pascual Amorós, JJ.; Maertens, L.; Gidenne, T.; Xiccato, G.; García, J. (2005). Recommendations and guidelines for applied nutrition experiments in rabbits. World Rabbit Science. 13. doi:10.4995/wrs.2005.516SWORD1

Early development and reproductive lifespan of rabbit females: implications of growth rate, rearing diet and body condition at first mating

[EN] Factors influencing early development such as birth weight, nest competition, and the diet received during rearing have been proposed as elements conditioning the future reproductive performance of European rabbit (Oryctolagus cuniculus) females. To evaluate their effects, we followed the life of 1513 females from birth to time of death, culling or censoring (animals alive at a fixed date). Between 0 and 63 days of age 353 females died. From the remaining 1160 females, 864 were chosen based on their birth weight to be transferred from the selection to the production farm. At this farm, 431 females received the control diet (184g of CP, 381 g of NDF and 11.8 MJ of DE per kg DM), while the other 433 received the fibrous diet (134 g of CP, 436g of NDF and 10.0 MJ of DE per kg DM). Throughout the rearing period, we checked for the individual live weight and body condition (perirenal fat thickness) at first artificial insemination. Reproductive lifespan was defined as the number of days between the first parturition and the time of death, culling or censoring. Birth weight affected the survival of newborn females during lactation and the presence of a milk spot at birth (related to nest competition) increased the survivability of newborns weighing <45g (P <0.001). Rearing diet altered the growth curve of females and their body condition at first insemination. The diet also altered the relative risk of death during the rearing period, which was lower among females fed on the fibrous diet (-12.5%; P < 0.001). Therefore, a higher number of females fed with this diet reached their reproductive life, directly affecting the productivity measured per housed female. Fatter females at first insemination had smaller litter sizes and a higher risk of being culled than lean ones (P < 0.05). In general, the fibrous diet reduced the risk of leaving the herd at early rearing, and both birth weight and perirenal fat thickness affected female's reproductive lifespan. An excess of fat (positive change in one unit of perirenal fat) at their first insemination represented an increased the risk of death or elimination of 13%.The authors acknowledge Cesar Villalba (Fabara, Spain), Luis Eroles (Valderrobres, Spain) for the technical support in managing the animals and for kindly providing a space to conduct our study. They also thank the Commission for Science and Technology (CICYT) of the Spanish Government (AGL2014-53405-C2-1-P) for the economic support to carry out this study.Martinez-Paredes, E.; Ródenas Martínez, L.; Pascual Amorós, JJ.; Savietto, D. (2018). Early development and reproductive lifespan of rabbit females: implications of growth rate, rearing diet and body condition at first mating. animal. 12(11):2347-2355. https://doi.org/10.1017/S1751731118000162S23472355121

Welfare and performance results in meat rabbits during their lactation and fattening. A review

[EN] This review summarizes the main scientific works focused on the welfare of rabbits in lactation and growing periods. A suitable material for building the nest has a positive impact, improving kits' welfare by reducing their mortality. A careful and regular daily handling of newborns during lactation, such as habituation to the farmer, can provide less fearful and stressed rabbits even in adulthood, showing lower mortality in the group period and higher fertility later. At a similar density, fattening in conventional cages (6-9 rabbits) enriches specific behaviours (locomotor, social, exploratory) and provides bolder rabbits, reducing their daily growth and consumption, the slaughter weight and the muscle:bone ratio compared to individual cages. If locomotion is promoted by specific stimuli or with a larger area and group size, it increases the resistance and weight of the leg bones and can increase the hind part percentage. Physical activity and bone resistance are also increased in rabbits from large groups fattened in pens, but growth performance deteriorates and it is not sure that welfare is improved because rabbits show more injuries, higher glucocorticoids level and worse hygienic-sanitary conditions. Adding wooden objects (sticks or blocks) for gnawing in fattening cages does not have negative effect on growth performance traits, and could even improve them with blocks with trace elements, besides reducing the aggressiveness in larger fattening groups. Inclusion of a platform can enrich behaviours even though deteriorates several growth traits and the hygiene of these enclosures will be worsened.[ES] En esta revisión se estudian los principales resultados científicos orientados a mejorar el bienestar de los gazapos en el nido y en el periodo de cebo. Un material apropiado para que la coneja construya el nido reduce la mortalidad mejorando así las condiciones de bienestar en el nidal. La manipulación metódica de los gazapos durante la lactación les habitúa al cuidador, haciéndoles menos asustadizos y estresados, mostrando inferior mortalidad mientras crecen y mayor fertilidad posteriormente. Con similar densidad, el cebo en jaulas convencionales (6¿9 gazapos) enriquece comportamientos específicos (locomotor, social, exploratorio) y proporciona conejos más audaces, reduciendo su crecimiento y consumo diarios, el peso de sacrificio y la relación músculo:hueso respecto a las jaulas individuales. Si además se promueve la locomoción mediante estímulos o ampliando el espacio y tamaño del grupo, aumenta la resistencia y peso de los huesos de la pierna y puede incrementar la proporción de tercio posterior. La actividad física y el desarrollo óseo también son mayores en parques grandes con elevado número de gazapos, pero sus resultados zootécnicos empeoran y no parecen alcanzar mayor bienestar, porque muestran más lesiones, elevado nivel de glucocorticoides y peores condiciones higiénico¿sanitarias. Aportar elementos de madera (varilla, bloque) en la jaula de cebo no deteriora los parámetros de crecimiento y puede mejorarlos si se incluyen elementos traza, reduciendo las lesiones en grupos más grandes de engorde en parque. El enriquecimiento mediante plataforma puede ampliar el repertorio de comportamientos pero perjudica algunos resultados de crecimiento y empeora la higiene de los recintos.López, M.; Cervera, C.; Pascual Amorós, JJ. (2021). Bienestar y resultados zootécnicos en conejos de carne durante su lactancia y engorde. Revisión bibliográfica. ITEA-Informacion Tecnica Economica Agraria. 117(2):108-129. https://doi.org/10.12706/itea.2020.014108129117