Psoroptes cuniculi infestation in pet rabbits in Tabasco, Mexico, 2021-2022.

BACKGROUND: Rabbits are an important worldwide meat- and fibre-producing animal, and they are popular pets. The rabbit ear mite, Psoroptes cuniculi, causes severe dermatological disease. Epidemiological data on P. cuniculi infestations are important for public health. OBJECTIVE: The objective of the study was to determine the frequency of P. cuniculi infestation in pet rabbits and evaluate epidemiological factors associated with infestation. ANIMALS: Two hundred pet rabbits presented for veterinary care between 2021 and 2022. MATERIALS AND METHODS: Physical examination, otoscopy and microscopy were used for ear mite identification. Association with age, sex, body mass index (BMI), breed, feeding and housing management was analysed. RESULTS: Of the 200 rabbits, 59 (29.5%) were positive for P. cuniculi. Only female sex had a positive association with P. cuniculi. CONCLUSIONS AND CLINICAL SIGNIFICANCE: Psoroptes cuniculi in pet rabbits has a similar frequency to that reported in meat-producing rabbits, and female sex had a positive association.

First Detection of Benign Rabbit Caliciviruses in Chile.

Pathogenic lagoviruses (Rabbit hemorrhagic disease virus, RHDV) are widely spread across the world and are used in Australia and New Zealand to control populations of feral European rabbits. The spread of the non-pathogenic lagoviruses, e.g., rabbit calicivirus (RCV), is less well studied as the infection results in no clinical signs. Nonetheless, RCV has important implications for the spread of RHDV and rabbit biocontrol as it can provide varying levels of cross-protection against fatal infection with pathogenic lagoviruses. In Chile, where European rabbits are also an introduced species, myxoma virus was used for localised biocontrol of rabbits in the 1950s. To date, there have been no studies investigating the presence of lagoviruses in the Chilean feral rabbit population. In this study, liver and duodenum rabbit samples from central Chile were tested for the presence of lagoviruses and positive samples were subject to whole RNA sequencing and subsequent data analysis. Phylogenetic analysis revealed a novel RCV variant in duodenal samples that likely originated from European RCVs. Sequencing analysis also detected the presence of a rabbit astrovirus in one of the lagovirus-positive samples.

Determination of intraocular pressure and Schirmer tear test and the comparison between the applanation tonometer (Tono-Pen AVIA®) and the rebound tonometer (TonoVet Plus®) in mini lionhead rabbits.

OBJECTIVE: To determine intraocular pressure (IOP) and tear production, as well as to compare the IOP obtained with the TonoVet Plus® (rebound) with the Tono-Pen Avia® (applanation) tonometers. ANIMALS: Twenty-five Mini Lionhead rabbits (n = 50 eyes). PROCEDURE: Tear production was measured at 6:00 a.m. and 6:00 p.m. by using the STT. The IOP reading was performed with the rebound tonometer, followed by the applanation tonometer, at 6:00 a.m., 9:00 a.m., 12:00 p.m., 3:00 p.m., and 6:00 p.m. Regression analysis, analysis of variance (anova) and Bland-Altman statistics were used. RESULTS: Daily tear production was 10.25 ± 3.75 mm/min, with no differences among the moments evaluated. Average daily IOP was 17.7 ± 3.08 mmHg with the TonoVet Plus® and 11.5 ± 4.56 mmHg with the Tono-Pen Avia®. IOP values were higher at the beginning and end of the day with both tonometers. CONCLUSION: The IOP values are higher with the TonoVet Plus® tonometer. The reference values of IOP and tear production obtained in this work may support the diagnosis, treatment, and monitoring of ocular disorders in pet Mini Lionhead rabbits.

European Rabbit Invasion in a Semi-Arid Ecosystem of Chile: How Relevant Is Its Role in Food Webs?

The European rabbit (Oryctolagus cuniculus) is one of the main invasive species in Chile, where it became naturalized ca. 150 years ago. Their high reproductive capacity, lack of specialist predators, and great adaptability favored the settlement of rabbits in diverse mainland and island ecosystems of the country. Recently, rabbits have become central players in semi-arid ecosystems, such as those represented in Las Chinchillas National Reserve in north-central Chile. We undertook to analyze the place and role of rabbits in the food web of that Reserve, based on a bibliographic review and long-term annual data gathered from 1987 until 2022 (36 years). Results showed that the network comprised 77 species, where 69% were primary producers (plants), 18% were mid-level consumers (herbivores), and 13% were top-level consumers (predators). The most connected species in the food web was the rabbit, which positively or negatively affected the species interacting with it. Predators such as Galictis cuja, Geranoaetus polyosoma, Leopardus colocolo, and Puma concolor, and the scavenger Vultur gryphus, could be negatively affected by an eventual decrease (natural or human-caused) in the rabbit population of the Reserve. To the contrary, primary producers such as Oxalis perdicaria, Plantago hispidula, Schizanthus parvulus, Senna cumminggi, and Tropaeolum azureum could be positively affected by an increase in their biomass in response to a decrease in rabbits, favoring native rodents. We consider that analyzing the rabbit-centered food web and its impacts on native interacting species allows a better understanding of the relevance of invasive species in the local community, providing conceptual tools for rabbit management.

Patterns and predictors of inter-litter differences in rabbit pup locomotor activity, based on an automatized quantification method.

Individual-level sibling interactions in the litter huddle have been studied extensively, especially in the domestic rabbit (Oryctolagus cuniculus). However, little is known about inter-litter differences in pup activity patterns during early postnatal life, in particular regarding the drivers of such variation. In our study on 2-3-day-old rabbit pups, we predicted lower locomotor activity in litters with lower mean body masses on the day of birth (starting body mass) and with lower daily milk intake per pup, possibly constituting a behavioral strategy of pups to cope with associated energetic constraints. For an automatized assessment of pup locomotor activity in the litter huddle, we successfully developed and validated a method based on the quantification of dissimilarities between consecutive frames of video footage. Using this method, we could confirm a U-shaped time course of litter-level locomotor activity, with maximum values shortly before and after the once-daily nursing typical for the rabbit. As predicted, between-litter variation in mean starting body mass and in daily milk intake affected the degree of locomotor activity in the litter huddle, in an interactive way. That is, in litters with heavier starting body masses, pup locomotor activity was greater in pups with an initially higher milk intake, suggesting that only pups with better body condition and a higher energy intake could afford higher levels of activity. This interaction was exclusively apparent during the middle phase of the 24 h inter-nursing interval, when litter activity was low. Shortly before nursing, when pups show higher levels of locomotor behavior in anticipation of the mother's arrival, and shortly after nursing when the pups were more active possibly due to adjustments of their positions in the huddle, activity levels were decoupled from pups' starting body mass and previous milk intake. Our findings highlight the importance of pup body mass and daily energy intake, two parameters known to be related to maternal characteristics, in shaping inter-litter differences in pup locomotor activity.

Caracterización de los sistemas productores de conejos en el municipio Ciego de Ávila, Cuba / Characterization of rabbit production systems in the Ciego de Ávila municipality, Cuba

Resumen La crianza de conejos contribuye a la obtención de proteína animal, así como de ingresos por la venta de dicha especie. La descripción y caracterización de los sistemas de producción de estos animales arrojan información valiosa para el diseño de planes de intervención y mejoras. El objetivo del presente trabajo fue determinar las principales variables que influyen en la heterogeneidad de los sistemas productores de conejos en el municipio Ciego de Ávila, Cuba. La muestra estuvo formada por 49 fincas. Se obtuvo la información cuantitativa de indicadores productivos, reproductivos y sociales, a través de un análisis de factores, usando componentes principales (CP). Se calcularon las puntuaciones factoriales de cada caso, en cada CP, y los estadísticos descriptivos de los indicadores medidos. En las condiciones del territorio estudiado, la eficiencia estuvo determinada por 6 CP que explicaron el 77.6 % de la varianza: 1) tamaño del rebaño y áreas de forrajes; 2) comportamiento reproductivo; 3) edad del productor y manejo reproductivo; 4) mortalidad; 5) edad al destete y sacrificio y 6) número de montas para gestar las conejas. La caracterización a partir del uso de CP, y el índice factorial de cada caso de estudio en cada CP, sirve de base para interpretar la gran heterogeneidad existente en los indicadores estudiados, así como su similitud, y contribuye a definir relaciones y comportamientos en la caracterización de fincas cunícolas en esta región, lo que permitirá implementar planes de mejora productiva.

Abstract The breeding of rabbits contributes to obtaining animal protein and generating income from the sale of this species. The description and characterization of the production systems of these animals provide valuable information for the design of intervention and improvement plans. The aim of this study was to determine the main variables that influence the heterogeneity of the rabbit production systems in the Ciego de Ávila municipality, Cuba. The sample consisted of 49 farms. Quantitative data on productive, reproductive and social indicators were obtained through factor analysis using principal components (PC). The factor scores of each case were calculated, in each PC, and descriptive statistics of the indicators measured. In the conditions of the studied territory, the efficiency was determined by 6 PC that explained 77.6 % of the variance: 1) size of the herd and forage areas; 2) reproductive behavior; 3) age of the producer and reproductive management; 4) mortality; 5) age at weaning and age at slaughter and 6) number of mounts to gestate the breeders. The characterization from the use of PC, and the factor index for each case study in each PC, serve as the basis for interpreting the great existing heterogeneity in the indicators studied, as well as their similarity. It also contributes to defining relationships and behaviors in the characterization of rabbit farms in this region, which will allow the implementation of productive improvement plans.

Nonlinear mixed models for characterization of growth trajectory of New Zealand rabbits raised in tropical climate.

OBJECTIVE: The identification of nonlinear mixed models that describe the growth trajectory of New Zealand rabbits was performed based on weight records and carcass measures obtained using ultrasonography. METHODS: Phenotypic records of body weight (BW) and loin eye area (LEA) were collected from 66 animals raised in a didactic-productive module of cuniculture located in the southern Piauí state, Brazil. The following nonlinear models were tested considering fixed parameters: Brody, Gompertz, Logistic, Richards, Meloun 1, modified Michaelis-Menten, Santana, and von Bertalanffy. The coefficient of determination (R2), mean squared error, percentage of convergence of each model (%C), mean absolute deviation of residuals, Akaike information criterion (AIC), and Bayesian information criterion (BIC) were used to determine the best model. The model that best described the growth trajectory for each trait was also used under the context of mixed models, considering two parameters that admit biological interpretation (A and k) with random effects. RESULTS: The von Bertalanffy model was the best fitting model for BW according to the highest value of R2 (0.98) and lowest values of AIC (6,675.30) and BIC (6,691.90). For LEA, the Logistic model was the most appropriate due to the results of R2 (0.52), AIC (783.90), and BIC (798.40) obtained using this model. The absolute growth rates estimated using the von Bertalanffy and Logistic models for BW and LEA were 21.51g/d and 3.16 cm2, respectively. The relative growth rates at the inflection point were 0.028 for BW (von Bertalanffy) and 0.014 for LEA (Logistic). CONCLUSION: The von Bertalanffy and Logistic models with random effect at the asymptotic weight are recommended for analysis of ponderal and carcass growth trajectories in New Zealand rabbits. The inclusion of random effects in the asymptotic weight and maturity rate improves the quality of fit in comparison to fixed models.

Effect of season and housing systems on various physio-behavioral attributes of local breed of rabbits (Oryctolagus cuniculus) in Southern Punjab, Pakistan / Efeito da estação e dos sistemas de alojamento em vários atributos fisiocomportamentais da raça local de coelhos (Oryctolagus cuniculus) no sul de Punjab, Paquistão

The present study was conducted to investigate the effect of season and various housing systems on behavioral i.e. sitting, standing, walking and physiological i.e. respiratory rate (RR), rectal temperature (RT), time of sexual libido (TSL) attributes of local breed of rabbits reared in Southern Punjab, Pakistan. Adult rabbits (n = 40) of 6 month to 1 year old were divided into two groups (n = 20 / group). Group I was placed under traditional colony system in the soil while group II was kept under modern cage system. Sitting and standing was significantly (p ≤ 0.05) higher during summer and winter respectively. The RR and RT were significantly (p ≤ 0.05) higher in summer as compared to other study seasons. Standing behavior was significantly (p ≤ 0.05) higher in caged rabbits as compared to colony-reared ones. Statistically higher (p ≤ 0.05) TSL value was observed in summer as compared to other three study seasons. From this study it is concluded that rabbit's behavioral and physiological traits are significantly affected by season and housing systems. We concluded that rabbits show better physio-behavioral performance in autumn and winter season while summer stress negatively affects physiology and behavior under caged-system. This study could contribute new aspects of behavioral and physiological processes in local breed of rabbits due to different seasons and housing systems.

O presente estudo foi conduzido para investigar o efeito da estação do ano e de vários sistemas de alojamento nos atributos comportamentais, isto é, sentar, levantar, andar e fisiológico, isto é, frequência respiratória (RR), temperatura retal (TR), tempo de libido sexual (TSL), atributos da raça local de coelhos criados no sul de Punjab, Paquistão. Coelhos adultos (n = 40) de 6 meses a 1 ano de idade foram divididos em dois grupos (n = 20 / grupo). O grupo I foi colocado sob o sistema de colônia tradicional no solo, enquanto o grupo II foi mantido sob o sistema moderno de gaiolas. Sentar e ficar em pé foi significativamente (p ≤ 0,05) maior durante o verão e inverno, respectivamente. O RR e o TR foram significativamente (p ≤ 0,05) maiores no verão, em comparação com as outras estações do estudo. O comportamento em pé foi significativamente (p ≤ 0,05) maior em coelhos engaiolados, em comparação com os criados em colônia. O valor de TSL estatisticamente maior (p ≤ 0,05) foi observado no verão, em comparação com outras três temporadas de estudo. A partir deste estudo, concluiu-se que os traços comportamentais e fisiológicos dos coelhos são significativamente afetados pela estação do ano e pelos sistemas de alojamento. Concluímos que os coelhos apresentam melhor desempenho fisiocomportamental no outono e inverno, enquanto o estresse do verão afeta negativamente a fisiologia e o comportamento em sistema enjaulado. Este estudo pode contribuir com novos aspectos dos processos comportamentais e fisiológicos em raças locais de coelhos devido às diferentes estações do ano e sistemas de alojamento.

Diferente asimetría craneal según sexo en el conejo toy / Different skull asymmetry according to sex in toy rabbits

RESUMEN: Los conejos denominados toy son seleccionados por su apariencia pedomórfica ('infantilizada'). El objetivo principal de este estudio fue analizar las asimetrías craneales en este tipo de conejo. Para ello, se estudiaron un total de 46 cráneos adultos (9 machos y 37 hembras), recurriéndose a técnicas de morfométrica geométrica a partir 10 hitos anatómicos pareados y 3 en el plano sagital, en la cara dorsal del cráneo. Nuestra hipótesis es que a través de la selección artificial en los machos (objetivo principal para la obtención de nuevos fenotipos) las asimetrías se expresarán como valores de asimetría más altos. El tamaño de los cráneos resultó similar entre ambos sexos, pero presentaban la asimetría fluctuante fue mayor en machos. La asimetría fluctuante se considera un indicador negativo de la capacidad de resistir pequeñas anomalías en su desarrollo, anomalías que son generalmente el resultado de estrés genético o ambiental. En otras palabras, los machos estarían sujetos a una selección más fuerte y, en consecuencia, se verían más afectados por el manejo, en comparación con las hembras. Estos resultados pueden facilitar la comprensión de los patrones y procesos subyacentes al dimorfismo sexual en fenotipos extremos, como lo son los de los conejos toy.

SUMMARY: Toy rabbits are selected for their paedomorphic ('babyish') appearance. The main objective of this study is to analyse the skull asymmetries of toy rabbits. For this purpose, a total of 46 adult skulls (9 males and 37 females) were studied. Geometric morphometric technique with five pairs of anatomical landmarks and three on sagittal plane on dorsal aspect of skull was used. Our hypothesis is that through artificial selection on males (which are the main subject for obtaining new phenotypes among toys) asymmetries will be expressed as higher asymmetrical values. Skulls' size was similar between sexes, but males presented a higher level of fluctuating asymmetry. Fluctuating asymmetry indicates a negative ability to buffer subtle developmental anomalies, normally from genetic or environmental origin. In other words, males would be under stronger directed selection and consequently be more affected by management (including selective) factors compared to females. These results can allow a better understanding of the patterns and processes underlying sexual shape dimorphism, especially with extreme phenotypes, as toy rabbits are.

Effects of canine adipose-derived mesenchymal stem cells on the epithelialization of rabbits' skin autograft (Oryctolagus cuniculus) / Efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães na epitelização de autoenxertos de pele em coelhos (Oryctolagus cuniculus)

The present study aimed to evaluate the effects of mesenchymal stem cells derived from canine adipose tissue in the healing process of full-thickness mesh skin grafts in rabbits. The stem cells were collected from young dogs; and, after characterization, remained in cryopreservation, in independent doses containing 2 x 106 cells. The mesh distal limb graft technique was performed in 60 rabbits, divided into three groups, CG (Control Group), GT1 (Intralesional Stem Cell Treated Group), and GT2 (Intravenous Stem Cell Treated Group), containing 20 animals each. After grafting, each group was randomly divided into four subgroups according to euthanasia time 3, 7, 14, and 30 days, containing five animals in each group. Animals of GT1_14, GT1_30, and GT2_14, GT2_30 subgroups received a second dose of xenogeneic cells on the seventh day. Meanwhile, animals from GT1_30 and GT2_30 received the third dose of xenogeneic cells on day 14. The groups treated with xenogeneic stem cells positively affected type III collagen re-epithelialization and deposition, and possibly GT1 had a controlled inflammatory response. However, no effect on angiogenesis. Thus, it was possible to demonstrate tolerance and therapeutic action of mesenchymal stem cells from canine adipose tissue in skin grafts in rabbits.(AU)

O presente estudo teve como principal objetivo avaliar os efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães no processo de cicatrização de autoenxertos de pele de espessura total em malha em coelhos. As células-tronco foram coletadas de cães jovens, após a caracterização estas permaneceram em criopreservação, em doses individuais contendo 2 x 106 células. A técnica de enxerto em malha na região distal do membro foi realizada em 60 coelhos, divididos em três grupos, GC (Grupo Controle), GT1 (Grupo tratado com células-tronco intralesional) e GT2 (Grupo tratado com células-tronco via endovenosa), contendo 20 animais cada. Imediatamente após a enxertia, cada grupo foi dividido aleatoriamente em quatro subgrupos, de acordo com o tempo de eutanásia 3, 7, 14 e 30 dias contendo cinco animais cada. Animais dos subgrupos GT1_14, GT1_30 e GT2_14, GT2_30 receberam uma segunda dose de células xenógenas no sétimo dia. Ademais, animais do GT1_30 e do GT2_30 receberam a terceira dose de células xenógenas no dia 14. Os grupos tratados com células-tronco xenógenas tiveram um efeito positivo na reepitelização e deposição de colágeno tipo III, e possivelmente, o GT1 teve uma resposta inflamatória controlada, entretanto o efeito na angiogênese não foi observado. Dessa forma, foi possível demonstrar que houve tolerância e ação terapêutica das células-tronco mesenquimais derivadas do tecido adiposo de cães em enxertos de pele em coelhos.(AU)

Effects of canine adipose-derived mesenchymal stem cells on the epithelialization of rabbits' skin autograft (Oryctolagus cuniculus) / Efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães na epitelização de autoenxertos de pele em coelhos (Oryctolagus cuniculus)

The present study aimed to evaluate the effects of mesenchymal stem cells derived from canine adipose tissue in the healing process of full-thickness mesh skin grafts in rabbits. The stem cells were collected from young dogs; and, after characterization, remained in cryopreservation, in independent doses containing 2 x 106 cells. The mesh distal limb graft technique was performed in 60 rabbits, divided into three groups, CG (Control Group), GT1 (Intralesional Stem Cell Treated Group), and GT2 (Intravenous Stem Cell Treated Group), containing 20 animals each. After grafting, each group was randomly divided into four subgroups according to euthanasia time 3, 7, 14, and 30 days, containing five animals in each group. Animals of GT1_14, GT1_30, and GT2_14, GT2_30 subgroups received a second dose of xenogeneic cells on the seventh day. Meanwhile, animals from GT1_30 and GT2_30 received the third dose of xenogeneic cells on day 14. The groups treated with xenogeneic stem cells positively affected type III collagen re-epithelialization and deposition, and possibly GT1 had a controlled inflammatory response. However, no effect on angiogenesis. Thus, it was possible to demonstrate tolerance and therapeutic action of mesenchymal stem cells from canine adipose tissue in skin grafts in rabbits.(AU)

O presente estudo teve como principal objetivo avaliar os efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães no processo de cicatrização de autoenxertos de pele de espessura total em malha em coelhos. As células-tronco foram coletadas de cães jovens, após a caracterização estas permaneceram em criopreservação, em doses individuais contendo 2 x 106 células. A técnica de enxerto em malha na região distal do membro foi realizada em 60 coelhos, divididos em três grupos, GC (Grupo Controle), GT1 (Grupo tratado com células-tronco intralesional) e GT2 (Grupo tratado com células-tronco via endovenosa), contendo 20 animais cada. Imediatamente após a enxertia, cada grupo foi dividido aleatoriamente em quatro subgrupos, de acordo com o tempo de eutanásia 3, 7, 14 e 30 dias contendo cinco animais cada. Animais dos subgrupos GT1_14, GT1_30 e GT2_14, GT2_30 receberam uma segunda dose de células xenógenas no sétimo dia. Ademais, animais do GT1_30 e do GT2_30 receberam a terceira dose de células xenógenas no dia 14. Os grupos tratados com células-tronco xenógenas tiveram um efeito positivo na reepitelização e deposição de colágeno tipo III, e possivelmente, o GT1 teve uma resposta inflamatória controlada, entretanto o efeito na angiogênese não foi observado. Dessa forma, foi possível demonstrar que houve tolerância e ação terapêutica das células-tronco mesenquimais derivadas do tecido adiposo de cães em enxertos de pele em coelhos.(AU)

Cashew nut meal (Anacardium occidentale L) in the feeding of growing rabbits / Farelo de castanha de caju (Anacardium occidentale L) na alimentação de coelhos em crescimento

Two trials were conducted: (1) to determine the chemical composition, digestibility of nutrients and energy of cashew nut meal (CNM); and (2) to evaluate the effects of increasing its levels (0, 5, 10, 15, 20 and 25%) in diets for growing rabbits on performance, carcass characteristics and economic evaluation. The digestibility assay utilized 24 rabbits (55 days of age), distributed in a completely randomized design with two treatments and 12 repetitions, with one reference and another test feed composed of 70% basal diet and 30% CNM. The digestibility of dry matter, crude protein and gross energy from CNM were, respectively, 76.61, 61.71 and 56.53%. The digestible dry matter, digestible protein and digestible energy were, respectively, 74.28, 16.97 and 3,549 kcal/kg. The performance assay utilized 120 rabbits, with an average of 45 days of age and weight 1090 ± 151g, distributed in a completely randomized design with six treatments and 10 repetitions with two rabbits of the same sex per cage. The inclusion of CNM above 5% promoted a linear reduction in feed intake and improved feed conversion, without affecting weight gain and carcass characteristics to the 20% level of inclusion. There was also a linear reduction in feed cost per kilogram of weight gain and linear improvement in rates of economic efficiency and cost index up to 25% CNM inclusion. Based on these findings - and to not hurt performance - it is recommended to include up to 20% CNM in rabbits' diet.(AU)

Dois ensaios foram realizados: (1) para determinar a composição química, digestibilidade dos nutrientes e energia do farelo de castanha de caju (FCC) e avaliar os efeitos do aumento dos níveis (0, 5, 10, 15, 20 e 25%) em dietas para coelhos em crescimento sobre desempenho, características de carcaça e avaliação econômica. O ensaio de digestibilidade utilizou 24 coelhos (55 dias de idade), distribuídos em delineamento inteiramente casualizado, com dois tratamentos e 12 repetições, sendo uma ração referência e outra ração teste composta por 70% de dieta basal e 30% de FCC. A digestibilidade da matéria seca, proteína bruta e energia bruta do FCC foram, respectivamente, 76,61; 61,71 e 56,53%. A matéria seca digestível, a proteína digestível e a energia digestível foram, respectivamente, 74,28; 16,97 e 3,549 kcal / kg. O ensaio de desempenho utilizou 120 coelhos, com média de 45 dias de idade e peso de 1090 ± 151g, distribuídos em delineamento inteiramente casualizado, com seis tratamentos e 10 repetições com dois coelhos do mesmo sexo por gaiola. A inclusão de FCC acima de 5% promoveu uma redução linear no consumo de ração e melhor conversão alimentar, sem afetar as características de ganho de peso e carcaça para o nível de inclusão de 20%. Também foi observada redução linear no custo de alimentação por quilograma de ganho de peso e melhora linear nas taxas de eficiência econômica e índice de custos até 25% de inclusão do FCC. Com base nesses resultados - e para não prejudicar o desempenho - é recomendável incluir até 20% de FCC na dieta de coelhos.(AU)

Intracameral tenecteplase during phacoemulsification in rabbits: clinical assessment of the anterior segment and biochemical analysis of the aqueous humor / Tenecteplase intracameral durante a facoemulsificação em coelhos: avaliação clínica do segmento anterior e análise bioquímica do humor aquoso

To evaluate the use of tenecteplase in transoperative phacoemulsification in healthy rabbits, the study was carried out with fifteen New Zealand rabbits, divided into three groups: control group (CG), untreated group (UG) and treated group (TG). UG and TG were operated by phacoemulsification and TG received 50 µg / 0.3 mL of intracameral tenecteplase. The postoperative evaluations were 24 h, 72 h, 7 days, 15 days and 21 days. In TP21 the animals were submitted to euthanasia and aqueous humor samples were collected. No significant differences were observed in the clinical evaluations between CG and TG in relation to incidence rates of intraocular pressure (IOP), corneal edema, fibrin deposits, hyphema, aqueous flare and synechia. In the physicochemical evaluation of the aqueous humor, there were no significant differences between the three groups in relation to pH values and concentrations of chloride ions. The aqueous humor density values were statistically different between CG and the other groups. In the histological evaluation, there were no significant differences between the groups. The use of tenecteplase in transoperative phacoemulsification in rabbits did not present significant differences in terms of clinical, physicochemical and histological parameters.(AU)

Para avaliar o uso da tenecteplase na facoemulsificação transoperatória em coelhos sadios, o estudo foi realizado com quinze coelhos da raça Nova Zelândia, divididos em três grupos: grupo controle (CG) grupo não tratado (UG) e grupo tratado (TG). UG e TG foram operados por facoemulsificação e TG recebeu 50 µg / 0,3 mL de tenecteplase intracameral. As avaliações pós-operatórias foram 24 h, 72 h, 7 dias, 15 dias e 21 dias. No TP21 os animais foram submetidos à eutanásia e amostras de humor aquoso foram coletadas. Não foram observadas diferenças significativas nas avaliações clínicas entre o CG e o TG em relação às taxas de incidência de pressão intraocular (PIO), edema de córnea, depósitos de fibrina, hifema, flare aquoso e sinéquia. Na avaliação físico-química do humor aquoso, não houve diferenças significativas entre os três grupos em relação aos valores de pH e concentrações de íons cloreto. Os valores de densidade de humor aquoso foram estatisticamente diferentes entre CG e os outros grupos. Na avaliação histológica, não houve diferenças significativas entre os grupos. O uso da tenecteplase na facoemulsificação transoperatória em coelho não apresentou diferenças significativas em termos de parâmetros clínicos, físico-químicos e histológicos.(AU)

Prevalencia y hallazgos radiográficos en conejos, cuyos y chinchillas diagnosticados con maloclusión en el Hospital Veterinario de Especialidades en Fauna Silvestre y Etología Clínica de la UNAM, México / Prevalence and radiographic findings in rabbits, guinea pigs and chinchillas diagnosed with malocclusion at the UNAM Exotic Pet and Wildlife Teaching Hospital, Mexico

RESUMEN Los lagomorfos y los histricomorfos, como los cuyos y las chinchillas, comparten características dentales como: dentadura elodonta e hipsodonta. Estas peculiaridades predisponen la presentación de maloclusión debido al consumo de dietas inadecuadas, poco abrasivas. El propósito de este trabajo es identificar la prevalencia de maloclusión en cada una de las especies mencionadas, de acuerdo con su sexo y grupo etario. Además, tiene como objetivo hacer una evaluación objetiva de los estudios radiográficos de los ejemplares, basada en líneas de referencia anatómica, para determinar los principales hallazgos radiográficos según el grado de maloclusión diagnosticado de forma clínica. El 30% de todos los individuos evaluados presentaron problemas de maloclusión, 42,86% de ellos conejos, 16,6% cuyos y 23% chinchillas. No se evidenciaron diferencias significativas en la presentación por sexo. En conejos fue más común el diagnóstico de ejemplares del grupo etario I y II, mientras que en cuyos lo fue en los grupos II y III. El grado I y II fueron los más diagnosticados en conejos y cuyos. En las radiografías las lesiones más comunes fueron el sobrecrecimiento de las raíces maxilares y mandibulares, elongación de incisivos, pérdida de la superficie de oclusión y deformación de las raíces mandibulares. Se propone un método de corrección para las proyecciones radiográficas LL con rotación evidente para mantener la objetividad de la evaluación radiográfica.

ABSTRACT Lagomorphs and histricomorphs, as guinea pigs and chinchillas, have common dental characteristics, such as the elodont and hypsodont teeth. These peculiarities predispose to the presentation of malocclusion due to the consumption of inadequate, non-abrasive diets. The purpose of this work is to identify the prevalence of malocclusion in each case. In addition, it aims to make an objective evaluation of the radiological studies of the specimens, based on anatomical reference lines, to determine the main radiographic findings according to the degree of malocclusion clinically diagnosed. 30% of the individuals evaluated presented malocclusion problems being 42.86% rabbits, 16.6% guinea pigs and 23% chinchillas. There is no evidence of significant differences in the presentation by sex. In rabbits, the diagnosis of the specimens from the group I and II were more common, while in guinea pigs they were II and Ill. Grade I and II were the most diagnosed in rabbits and guinea pigs. In the radiographs, the most common lesions are the overgrowth of the maxillary and mandibular roots, elongation of the incisors, loss of the occlusal surface and deformation of the mandibular roots. A method of correction for LL radiographic projections with evident rotation is proposed to maintain the objectivity of the radiographic evaluation.

Intracameral tenecteplase during phacoemulsification in rabbits: clinical assessment of the anterior segment and biochemical analysis of the aqueous humor / Tenecteplase intracameral durante a facoemulsificação em coelhos: avaliação clínica do segmento anterior e análise bioquímica do humor aquoso

To evaluate the use of tenecteplase in transoperative phacoemulsification in healthy rabbits, the study was carried out with fifteen New Zealand rabbits, divided into three groups: control group (CG), untreated group (UG) and treated group (TG). UG and TG were operated by phacoemulsification and TG received 50 µg / 0.3 mL of intracameral tenecteplase. The postoperative evaluations were 24 h, 72 h, 7 days, 15 days and 21 days. In TP21 the animals were submitted to euthanasia and aqueous humor samples were collected. No significant differences were observed in the clinical evaluations between CG and TG in relation to incidence rates of intraocular pressure (IOP), corneal edema, fibrin deposits, hyphema, aqueous flare and synechia. In the physicochemical evaluation of the aqueous humor, there were no significant differences between the three groups in relation to pH values and concentrations of chloride ions. The aqueous humor density values were statistically different between CG and the other groups. In the histological evaluation, there were no significant differences between the groups. The use of tenecteplase in transoperative phacoemulsification in rabbits did not present significant differences in terms of clinical, physicochemical and histological parameters.

Para avaliar o uso da tenecteplase na facoemulsificação transoperatória em coelhos sadios, o estudo foi realizado com quinze coelhos da raça Nova Zelândia, divididos em três grupos: grupo controle (CG) grupo não tratado (UG) e grupo tratado (TG). UG e TG foram operados por facoemulsificação e TG recebeu 50 µg / 0,3 mL de tenecteplase intracameral. As avaliações pós-operatórias foram 24 h, 72 h, 7 dias, 15 dias e 21 dias. No TP21 os animais foram submetidos à eutanásia e amostras de humor aquoso foram coletadas. Não foram observadas diferenças significativas nas avaliações clínicas entre o CG e o TG em relação às taxas de incidência de pressão intraocular (PIO), edema de córnea, depósitos de fibrina, hifema, flare aquoso e sinéquia. Na avaliação físico-química do humor aquoso, não houve diferenças significativas entre os três grupos em relação aos valores de pH e concentrações de íons cloreto. Os valores de densidade de humor aquoso foram estatisticamente diferentes entre CG e os outros grupos. Na avaliação histológica, não houve diferenças significativas entre os grupos. O uso da tenecteplase na facoemulsificação transoperatória em coelho não apresentou diferenças significativas em termos de parâmetros clínicos, físico-químicos e histológicos.

Cashew nut meal (Anacardium occidentale L) in the feeding of growing rabbits / Farelo de castanha de caju (Anacardium occidentale L) na alimentação de coelhos em crescimento

Two trials were conducted: (1) to determine the chemical composition, digestibility of nutrients and energy of cashew nut meal (CNM); and (2) to evaluate the effects of increasing its levels (0, 5, 10, 15, 20 and 25%) in diets for growing rabbits on performance, carcass characteristics and economic evaluation. The digestibility assay utilized 24 rabbits (55 days of age), distributed in a completely randomized design with two treatments and 12 repetitions, with one reference and another test feed composed of 70% basal diet and 30% CNM. The digestibility of dry matter, crude protein and gross energy from CNM were, respectively, 76.61, 61.71 and 56.53%. The digestible dry matter, digestible protein and digestible energy were, respectively, 74.28, 16.97 and 3,549 kcal/kg. The performance assay utilized 120 rabbits, with an average of 45 days of age and weight 1090 ± 151g, distributed in a completely randomized design with six treatments and 10 repetitions with two rabbits of the same sex per cage. The inclusion of CNM above 5% promoted a linear reduction in feed intake and improved feed conversion, without affecting weight gain and carcass characteristics to the 20% level of inclusion. There was also a linear reduction in feed cost per kilogram of weight gain and linear improvement in rates of economic efficiency and cost index up to 25% CNM inclusion. Based on these findings - and to not hurt performance - it is recommended to include up to 20% CNM in rabbits' diet.

Dois ensaios foram realizados: (1) para determinar a composição química, digestibilidade dos nutrientes e energia do farelo de castanha de caju (FCC) e avaliar os efeitos do aumento dos níveis (0, 5, 10, 15, 20 e 25%) em dietas para coelhos em crescimento sobre desempenho, características de carcaça e avaliação econômica. O ensaio de digestibilidade utilizou 24 coelhos (55 dias de idade), distribuídos em delineamento inteiramente casualizado, com dois tratamentos e 12 repetições, sendo uma ração referência e outra ração teste composta por 70% de dieta basal e 30% de FCC. A digestibilidade da matéria seca, proteína bruta e energia bruta do FCC foram, respectivamente, 76,61; 61,71 e 56,53%. A matéria seca digestível, a proteína digestível e a energia digestível foram, respectivamente, 74,28; 16,97 e 3,549 kcal / kg. O ensaio de desempenho utilizou 120 coelhos, com média de 45 dias de idade e peso de 1090 ± 151g, distribuídos em delineamento inteiramente casualizado, com seis tratamentos e 10 repetições com dois coelhos do mesmo sexo por gaiola. A inclusão de FCC acima de 5% promoveu uma redução linear no consumo de ração e melhor conversão alimentar, sem afetar as características de ganho de peso e carcaça para o nível de inclusão de 20%. Também foi observada redução linear no custo de alimentação por quilograma de ganho de peso e melhora linear nas taxas de eficiência econômica e índice de custos até 25% de inclusão do FCC. Com base nesses resultados - e para não prejudicar o desempenho - é recomendável incluir até 20% de FCC na dieta de coelhos.

Origin and antimeric distribution of the obturator nerves in the New Zealand rabbits / Origem e distribuição antimérica dos nervos obturatórios em coelhos Nova Zelândia

New Zealand rabbits are widely used as experimental models and represent an important casuistic in veterinary practices. The musculoskeletal conformation of rabbits frequently leads to the occurrence of lumbosacral lesions with neural involvement. In order to contribute to the comparative anatomy and the understanding of these lesions, the origin and distribution of the obturator nerves of 30 New Zealand rabbits (15 males and 15 females) previously fixed in 10% formaldehyde were studied by dissection. The obturator nerves were originated from the ventral spinal branches of L6 and L7 in 63.3% of the cases, L5 and L6 in 13.4%, only L7 in 13.4%, L7 and S1 in 6.6 % and of L6, L7 and S1 in 3.3%. The spinal segment that most contributed to the formation of the nerve was L7 (86.6% of the nerves). The obturator nerves emitted in all the specimens, a variable number of branches for the internal obturator, external obturator, pectineum, adductor and gracilis muscles. No significant differences were observed between the frequencies of the origin and muscular branches of the obturator nerves when comparing sex and antimers.(AU)

Coelhos da raça Nova Zelândia são amplamente usados como modelos experimentais e representam uma parcela importante dos atendimentos em consultórios veterinários. A conformação músculo-esquelética dos coelhos torna frequente a ocorrência de lesões lombossacrais com comprometimento neural. Visando contribuir para a anatomia comparada e no entendimento destas lesões, foram estudadas por dissecção a origem e a distribuição dos nervos obturatórios de 30 cadáveres de coelhos da raça Nova Zelândia (15 machos e 15 fêmeas) fixados previamente em formaldeído a 10%. O nervo obturatório formou-se a partir dos ramos ventrais de L6 e L7 em 63,3% dos casos, de L5 e L6 em 13,4%, apenas de L7 em 13,4%, de L7 e S1 em 6,6% e de L6, L7 e S1 em 3,3%. O segmento espinhal que mais contribuiu para a formação do nervo foi L7 (86,6% dos nervos). Os nervos obturatórios emitiram em todos os animais, número variável de ramos para os músculos obturador interno, obturador externo, pectíneo, adutor e grácil. Não foram observadas diferenças significativas entre as frequências da origem e de ramos musculares dos nervos obturatórios quando comparados sexo e antímeros.(AU)

Origin and antimeric distribution of the obturator nerves in the New Zealand rabbits / Origem e distribuição antimérica dos nervos obturatórios em coelhos Nova Zelândia

New Zealand rabbits are widely used as experimental models and represent an important casuistic in veterinary practices. The musculoskeletal conformation of rabbits frequently leads to the occurrence of lumbosacral lesions with neural involvement. In order to contribute to the comparative anatomy and the understanding of these lesions, the origin and distribution of the obturator nerves of 30 New Zealand rabbits (15 males and 15 females) previously fixed in 10% formaldehyde were studied by dissection. The obturator nerves were originated from the ventral spinal branches of L6 and L7 in 63.3% of the cases, L5 and L6 in 13.4%, only L7 in 13.4%, L7 and S1 in 6.6 % and of L6, L7 and S1 in 3.3%. The spinal segment that most contributed to the formation of the nerve was L7 (86.6% of the nerves). The obturator nerves emitted in all the specimens, a variable number of branches for the internal obturator, external obturator, pectineum, adductor and gracilis muscles. No significant differences were observed between the frequencies of the origin and muscular branches of the obturator nerves when comparing sex and antimers.

Coelhos da raça Nova Zelândia são amplamente usados como modelos experimentais e representam uma parcela importante dos atendimentos em consultórios veterinários. A conformação músculo-esquelética dos coelhos torna frequente a ocorrência de lesões lombossacrais com comprometimento neural. Visando contribuir para a anatomia comparada e no entendimento destas lesões, foram estudadas por dissecção a origem e a distribuição dos nervos obturatórios de 30 cadáveres de coelhos da raça Nova Zelândia (15 machos e 15 fêmeas) fixados previamente em formaldeído a 10%. O nervo obturatório formou-se a partir dos ramos ventrais de L6 e L7 em 63,3% dos casos, de L5 e L6 em 13,4%, apenas de L7 em 13,4%, de L7 e S1 em 6,6% e de L6, L7 e S1 em 3,3%. O segmento espinhal que mais contribuiu para a formação do nervo foi L7 (86,6% dos nervos). Os nervos obturatórios emitiram em todos os animais, número variável de ramos para os músculos obturador interno, obturador externo, pectíneo, adutor e grácil. Não foram observadas diferenças significativas entre as frequências da origem e de ramos musculares dos nervos obturatórios quando comparados sexo e antímeros.

Reproducción de conejos bajo condiciones tropicales, efectos negativos y posibles soluciones / Reproduction of rabbits under tropical conditions, negative effects and possible solutions

RESUMEN La fisiología digestiva y capacidad reproductiva hacen del conejo una especie con potencial para la producción de carne. En clima templado, su adecuado manejo reproductivo permite obtener entre 6 y 10 partos anuales con camadas de 6 y hasta 12 gazapos. En zonas tropicales, el estrés calórico disminuye su capacidad reproductiva. Las hembras presentan un incremento en la secreción de corticosteroides, modificando la secreción de la hormona liberadora de gonadotropina (GnRH), la hormona estimulante del folículo (FSH) y la hormona luteinizante (LH), disminuyendo el crecimiento y desarrollo folicular, calidad de ovocitos y la ovulación, y con ello el número de partos y tamaño de camada. En los machos se afecta la libido y la capacidad de monta. En la calidad seminal, disminuye 7.8 % el volumen, 7.7 % la concentración, 1.7 % la morfología y 5.5 % la motilidad. El objetivo del presente trabajo fue describir las estrategias utilizadas para disminuir el estrés calórico, que incluyó regular la temperatura en las instalaciones, suplementos alimenticios, cruzamiento de razas locales con razas mejoradas, desarrollo de líneas genéticas para climas tropicales, implementación de biotecnologías reproductivas como la inseminación artificial o criopreservación de semen, mejorando el comportamiento reproductivo del conejo bajo condiciones tropicales.

ABSTRACT The digestive physiology and reproductive capacity of the rabbit make it a species with potential for meat production. In a temperate climate, its adequate reproductive management allows to obtain between 6 and 10 annual litters per female with 6 up to 12 kits per litter. In tropical areas, heat stress alters metabolism and hormonal function, decreasing their reproductive capacity. In females, the main changes include an increase in the secretion of corticosteroids, modifying the secretion of gonadotropinreleasing hormone (GnRH), stimulating follicle hormone (FSH) and luteinizing hormone (LH), decreasing the growth and follicular development, oocyte quality and ovulation, and with it the number of births and size of litter. In males, libido and ability to mate are affected. In the seminal quality, a decrease of 7.8 % in volume, 7.7 % in concentration, 1.7 % in morphology and 5.5 % in motility is observed. The objective of the present work was to describe the strategies used to reduce the caloric stress. These included regulating the temperature in the facilities, supplementary food, crossing of local breeds with improved breeds, development of genetic lines for tropical climates, implementation of reproductive biotechnologies such as artificial insemination or cryopreservation of semen, improving the reproductive behavior of the rabbit under tropical conditions.

Oxidative stress and viability of adipose tissue-derived mesenchymal cell cultures from the omentum of rabbits / Estresse oxidativo e instabilidade genômica em culturas de células mesenquimais do tecido adiposo do omento de coelho

Mesenchymal stem cells are a population of somatic cells found in several tissues of an adult organism, including adipose tissue. Reactive oxygen species (ROS) can cause cellular alterations, including mutagenesis and genomic instability and the development of diseases. Thus, it is important to understand ROS-induced damage to cell macromolecules such as DNA, proteins, and lipids. In this study, we investigated oxidative stress rates and viability of adipose tissue-derived mesenchymal stem cells (ADSCs) from the greater omentum of rabbits. Cell cultures were analyzed at different passages (1-5) using the dichlorofluorescein acetate assay for measuring ROS production and cell viability tests. ROS levels were highest at passage 2 and cell viability was highest at passage 4.(AU)

Células-tronco mesenquimais são uma população de células somáticas encontradas em vários tecidos de um organismo adulto, incluindo o tecido adiposo. Espécies reativas de oxigênio (ROS) podem causar alterações celulares, incluindo mutagênese e instabilidade genômica e o desenvolvimento de doenças. Assim, é importante entender o dano induzido pelas EROs às macromoléculas celulares, como DNA, proteínas e lipídios. Neste estudo, investigamos as taxas de estresse oxidativo e viabilidade de células-tronco mesenquimais derivadas do tecido adiposo (ADSCs) a partir do omento maior de coelhos. As culturas celulares foram analisadas em diferentes passagens (1-5) utilizando o ensaio de acetato de diclorofluoresceína para medir a produção de ROS e testes de viabilidade celular. Os níveis de EROs foram mais altos na 2ª passagem e a viabilidade celular foi maior na 4ª passagem.(AU)