Effect of hair shearing on live performance and carcass traits of growing rabbits under hot ambient temperature

The aim of the study was to examine the effect of hair shearing in growing rabbits reared at high ambient temperature. The live performance and carcass traits of growing rabbits reared at 20°C (not sheared, C, n=50) or at 28°C (not sheared, H, n=50, or sheared at 5, 7 and 9 wk, HS, n=50) were compared. The ambient temperature and relative humidity were 20.5±1.1°C and 54±11% in the 20°C room and 28.8±0.2°C and 35±8% in 28°C room, respectively. Feed intake of H and HS groups decreased by 29.0 and 20.4%, respectively, compared to C rabbits (P<0.001). The same data for weight gain were 24.6 and 16.9% (P<0.001), and for body weight at 12 wk were 16.8 and 11.5% (P<0.001). At the same time, the feed conversion ratio improved (C: 3.53, HS: 3.34, H: 3.31; P<0.001). Nevertheless, the mortality rate of rabbits was not affected by the studied treatment and was overall low (0-4%). No differences were observed in dressing out percentages either (ratio of chilled carcass (CC) to the slaughter weight: 61.6-61.9%). The ratio of liver to CC differed among the experimental groups, with the highest value recorded in C group and the lowest in H group; HS rabbits showed intermediate results (C: 4.86%, HS: 4.27%, H: 3.91%; P<0.001). Lower ratios of fat deposits to reference carcass were also observed in rabbits kept at high ambient temperature (perirenal fat: C: 2.59%, HS: 1.82%, H: 1.60%; P<0.001; scapular fat: C: 0.89%, HS: 0.66%, H: 0.51%; P<0.001). It can be concluded that the negative effect of higher ambient temperature (28 vs. 20°C) on production in growing rabbits can be reduced significantly by hair shearing

Abstracts of the “26th Hungarian Conference on Rabbit Production”

About 100 participants attended the 26th Hungarian Conference on Rabbit Production at Kaposvár, organised by Kaposvár University, the Hungarian Branch of the WRSA and the Rabbit Production Board. This is the largest and most popular event for rabbit breeders in Hungary. Twenty papers were presented by senior and young scientists. Topics of the papers covered all fields of rabbit production (production, housing and welfare, reproduction, genetics, nutrition, meat quality). Full papers are available from the organiser ([email protected]) on request.World Rabbit Science (2015). Abstracts of the “26th Hungarian Conference on Rabbit Production”. Editorial Universitat Politècnica de València. doi:http://dx.doi.org/10.4995/wrs.2015.3455.SWORD475423

Novend\ue9knyulak v\ue0laszt\ue0sa tukros \ue9s tukor n\ue9lkuli ketrecek kozott.

Five week-old Pannon White rabbits were housed in a closed climatized rabbitry and randomly assigned to pens (56 rabbits) having a basic area of 1 m2 with a stocking density of 16 and 12 rabbits/m2 or to 18 individual cages (0.24 m2; 1 rabbit/cage; stocking density of 4 rabbits/m2). The pens and the cages were divided into 2 parts and animals could move freely among the 2 parts through swing doors. The vertical sides of one part of the pens and cages were completely covered with mirrors while the other part was covered with white plastic panels. A 24 hour video recording was performed twice a week using infrared cameras and the number of rabbits in each pen and cage was counted with a frequency of 15 minutes (96 times a day). The duration of the trial was 6 weeks. The lighting period was 16L/8D. Rabbits were fed ad libitum a standard diet and water was available ad libitum from nipple drinkers. Throughout the entire rearing period 67% of the individually caged rabbits showed a preference for the part of the cage enriched with mirrors (P<0.001). This preference slightly decreased with increasing age. The strong preference toward the part of the cage provided with mirror walls was independent of the time of day. That is, during the active period (11:00 pm \u2013 05:00 am), which corresponds to the dark part of the day, rabbits still preferred the mirror-side even though they were not able to see their own reflected image at that time. Neither rearing rabbits in groups under different stocking densities (12 vs 16 rabbits/m2) nor the presence of conspecifics reduced the interest toward mirrors. 65% of animals living at the stocking density of 16 rabbits/m2 and 61% of those living at the density of 12 rabbits/m2 were found on the side with mirrors (P<0.001) during all the recordings. Group-penned rabbits showed a decisive preference toward mirrors during the active period (71 to 74% for stocking densities of 12 and 16 rabbits/m2, respectively; P<0.001). The results suggest that the mirrors\u2019 presence offers some advantages, perhaps related to comfort and welfare that could be used as environmental enrichments for fattening rabbits. However, the installation costs should be taken into account before considering their use for long time individually caged animals and for grouppenned rabbits

Effect of restricted feeding after weaning on the productive and carcass traits of growing rabbits

The aim of the experiment was to study the influence of feeding medicated or non-medicated diets followed by a feed restriction after weaning on the productive and carcass traits of growing rabbits. Half of the rabbits was fed non-medicated (NOMED: 10.65 DE/kg, CP: 16.9%, CF: 17.3%; n=106) while the other half was fed medicated diet (MED: the same diet was supplemented with 500 mg/kg Oxitetraciclyn and 50 mg/kg Tiamuline; n=108) between 4 and 9 weeks of age, then they consumed non-medicated diet. Within both diet groups half of the rabbits was fed ad libitum (ADLIB) while the other half restricted (RESTR). In the latter group rabbits were allowed to consume for 9, 10, 12 or 14 hours between 4-5, 6-7, 7-8 or 8-9 weeks of age, respectively, then they were fed ad libitum. The feed intake was 26.7, 18.3 (P<0.001) and 5.3% (P=0.059) lower in the RESTR group at the ages of 4-5, 5-6 and 6-7 weeks, respectively. After 7 weeks of age no difference was found between groups. Body weight gain of RESTR rabbits was 20.9 (P<0.001) and 8.5% (P=0.039) lower at the ages of 4-5 and 5- 6 weeks, respectively, while between 6 and 8 weeks of age it slightly increased. Body weight of RESTR rabbits was 9.2% lower at 5 weeks of age compared to ADLIB group (871 vs. 959 g) but this was partly compensated at the end of the experiment (2737 vs. 2799 g, P=0.056). Feed conversion of RESTR group was better compared to ADLIB rabbits: 2.57 vs. 2.64 (P=0.01). No significant difference was found in the mortality (1 vs. 3.6%). Dressing out percentage (59.4 vs. 58.6%, P<0.001) and the proportions of hind part (19.2 vs. 18.8%), hind legs (18.3 vs. 18.0%) and that of the m. Longissimus dorsi (7.1 vs. 6.8%) to the body weight were higher in ADLIB rabbits. No difference was found in the proportion of perirenal fat. Production and mortality of MED and NOMED groups were similar however, the feed intake and the body weight gain of MED rabbits decreased during the transition from MED to NOMED diet at 9 weeks of age. Significantly higher dressing out percentage (59.5 vs. 58.5%, P<0.001) and proportion of fore and hind parts of carcass as well as that of the hind legs and m. Longissimus dorsi to the body weight were found in MED rabbits

EFFECT OF DIETARY SUPPLEMENTATION OF CHESTUNT HYDROLISABLE TANNIN ON DIGESTIVE EFFICIENCY, GROWTH PERFORMANCE AND MEAT QUALITY IN GROWING RABBITS

The aim of the study was to evaluate the effect of the dietary supplementation of chestnut hydrolysable tannin on the feed digestibility and nutritive value, mortality and growth performance, fatty acid profile and TBARS of cooked Longissimus dorsi (LD) meat. From the age of 18 days the rabbits were fed pellets supplemented with coccidiostat (CC) or with tannin (400 g/100 kg: T400). At weaning (35 d of age) within both groups 5 dietary sub-groups were formed: medicated-free (C0), containing coccidiostatic (CC), or supplemented with increasing levels of chestnut tannin (T200, T400 and T600). Rabbits fed the 5 diets ad libitum until slaughter at 11 weeks of age. The coefficient of total tract apparent digestibility (CTTAD) of nutrients was not affected by the tannin inclusion, substantially, with exception of CTTAD of hemicelluloses, that was lower in T400 and T600 compared to C0 and T200 (P<0.001), the CTTAD of Ca, lower in T400 vs C0 and CC (P<0.05) and CTTAD of DP-to-DE ratio, lowest in CC and T600 (P<0.001). Dietary tannin significantly modified the CTTAD of FA classes. At weaning, the live weight of CC rabbits was significantly higher than that of the T400 rabbits (974 vs 940 g, P<0.05). The other variables related to growth performance, health status and carcass traits were not affected by the tannin supplementation. The T400 diet fed before weaning seemed to be more effective than the 3 tannin levels administered during fattening period on FA profile change in the LD muscle. T400 diet fed before weaning increased SFA and MUFA (P<0.01) and decreased PUFA (P<0.05), decreasing the n-6/n-3 ratio (P<0.01), however. When tannin-supplemented diets were fed during fattening, only T600 diet showed significantly higher (P<0.05) SFA and MUFA contents compared to CC diet. In conclusion, the dietary inclusion of chestnut hydrolysable tannin doesn\u2019t provides improvements in health status, diet nutritive value, growth performance and carcass traits. Dietary hydrolysable tannin supplementation may play a role on lipid metabolism

Use of different areas of pen by growing rabbits depending on the elevated platforms\u2019 floor-type

The addition of platforms to rabbit cages increases their accessible area and provides rabbits greater freedom and mobility. Different types of platforms enable rabbits to situate themselves where they are most comfortable. The objective of this experiment was to analyse preference of growing rabbits between different areas of the pen depending on the elevated platforms\u2019 floor-type. Pens with a basic area of 0.84 m2 were equipped with platforms of 0.42 m2. Three types of flooring of the elevated platforms were used as treatments: deep-litter floor and an open wire-net floor (Experiment 1), and a deep-litter floor and a wire-net floor with a manure tray beneath it (Experiment 2). Growing rabbits (n = 168; 42 per treatment) between the ages of 5 and 11 weeks were studied, based on 24 h video recordings from infra-red cameras (one recording per week) applying scan sampling method with a frequency of 30 min. When the platform was deep-litter, significantly (P < 0.001) more rabbits used the area under the platform (53.7% and 54.3% in Experiments 1 and 2, respectively) than stayed on the platform (16.7% and 7.6%). In treatments of wire-net platform with and without tray beneath the platform also significantly (P < 0.001) more rabbits stayed under the platform (43.7% and 34.7%, respectively) than on the platform (19.5% and 29.9%, respectively). The differences from the expected 33.3% staying on the platform or under the platform were significant at least at the level of P < 0.05. The results show that the wire-net platform with the manure tray provides the optimal environment as it leads to the rabbits spreading themselves more evenly in the pen (i.e. the platform expands available floor area) without the risk of soiling from above, and without adverse effects on heat dissipation, and with the possibility of seeking cover when desired

Effect of feeding (only pellet or pellet plus hay) on productive and carcass traits of growing rabbits

The aim of the experiment was to examine the effect of feeding on productive performance and carcass traits, to get information about the difference between growing rabbits fed by only pellet and pellet plus hay. Pannon Ka does were inseminated with semen of Pannon Large and Hungarian Giant bucks. The crossbred rabbits (n=336) were weaned at 5 weeks of age. Half of them were housed in cages, the other half in pens (Cage: 3 rabbits/cage, Pen: 14 rabbits/pen, the stocking density was the same: 16 rabbits/m2 in each group). Two subgroups were formed based on the feeding method. Data (between 5 and 12 wk) were evaluated by multi-factor analysis of variance, but only the effect of feeding was calculated. The differences in body weight between Pellet and P+hay rabbits were significant from 9 weeks of age, in favour of Pellet group. It increased from 68 g at 9 weeks to 76 g at 12 weeks. The differences in weight gain and feed intake were significant between 5-12 weeks (11 and 1.3 g/day, respectively), in favour of Pellet rabbits. However, there were no significant differences in feed conversion ratio and mortality. The dressing out percentage was 0.4-0.7 % higher in Pellet group than in P+Hay rabbits. The ratio of hind part to reference carcass was higher in P+Hay group, and that of perirenal and scapular fat were higher in Pellet group. Feeding method did not influence the ratio of fore and mid parts to reference carcass. However, ratio of ear lesions was affected by feeding method (8.3 and 20.6 %; P=0.003, in pellet and P+hay, respectively). It can be concluded that feeding growing rabbits with pellet plus hay resulted significantly, but slightly lower body weight and longer fattening period to reach the same weight. On the other hand, animals fed by pellet plus hay realized less ear lesions

Effect of housing conditions on production, carcass and meat quality traits of growing rabbits

Production, carcass traits and meat quality of rabbits housed in cages or in different pens were compared. Rabbits (n = 579) were sorted into 5 groups: C = cage (2 rabbits/cage); pen without platform: P11 = 9 rabbits/pen; P16 = 14 rabbits/pen; pen with platform: PW = wire net platform, 14 rabbits/pen; PD = platform with straw-litter, 14 rabbits/pen. Feed intake and average daily gain between 5 and 11 weeks, and body weight at 11 weeks were significantly higher in C rabbits than that of the mean of pen-housed groups, while the PD group had the lowest growth performance. C rabbits had the smallest hind part to reference carcass (P b 0.001) and the largest percentage of perirenal and scapular fat (P b 0.001). The meat/bone ratio was the largest in group C (P b 0.05). Differences were recorded in a* value and lipid content of m. Longissimus dorsi. Rabbits housed in cages generally had the best performance whereas those housed in pens with platform exhibited the worst

The effect of the feed supplemented by different tannin levels on the production and carcass traits of growing rabbits

The objective of the experiment was to analyze the production and carcass traits of growing rabbits fed by medicament free and by supplemented (with coccidiostaticum, or with 3 different tannin levels) pellet, respectively. From the age of 18 days the rabbits were fed by medicament free pellet supplemented by coccidiostaticum (Cc), or by tannin (400g/100kg: T400). At weaning (35 days of age) within both groups 5 subgroups were formed: medicament free (CO), and supplemented pellet containing coccidiostaticum (Cc), or different levels of tannin (Farmatan) (T200, T400 and T600). At weaning the body weight of the Cc rabbits was significantly higher than that of the T400 rabbits (974 vs. 940g, P<0.05). Except for this finding the fed pellet type did not influence the growing rabbits\u2019 production (weight gain, body weight, feed consumption, feed conversion ratio, mortality). The pellet type fed prior to weaning significantly affected the perirenal fat weight (Cc = 28.9 and T400 = 26.3 g; P<0.05). The rabbits fed by tannin supplemented pellet after weaning had a higher mid part ratio compared to the reference carcass (P = 0.1). As the mortality rate was low in all groups (CO, T200 and T600 = 5.9%, T400 = 1.4%, Cc = 0%, NS), it can be concluded that no positive effect can be expected when the analyzed population is healthy and the housing conditions and the feed compositions are adequate

Effect of the feeding supplementation with chestnut hydrolysabletannin on the colour and oxidative stability of rabbit meat.

The aim of the study was to evaluate the effect of feeding growing rabbits with pelleted diets medicated-free, or medicated with coccidiostat, or with 3 different chestnut hydrolysable tannin levels, on the oxidative stability of the rabbit meat. From the age of 18 days the rabbits were fed pellets supplemented with coccidiostat (Cc), or with tannin (400g/100 kg: T400). At weaning (35 d of age) within both groups 5 sub-groups were formed: medicated-free (Co), and supplemented pellet containing coccidiost (Cc), or different levels of chestnut tannin (T200, T400 and T600). Rabbits were slaughtered at 11 weeks of age and Biceps femoris muscle was analysed for meat colour, hindleg meat for haem iron concentration, whereas Longissimus dorsi (LD) muscle was dissected and used for fatty acid (FA) profile, TBARS value and conjugated dienes determination. The tannin-supplemented diet T400 fed before weaning seemed to be more effective than the 3 tannin levels administered during fattening period on FA profile change in the LD muscle. T400 diet fed before weaning increased SFA and MUFA (P<0.01) and decreased PUFA (P<0.05), decreasing the n-6/n-3 ratio (P<0.01), however. During fattening, only T600 diet showed significant difference (P<0.05) compared to Cc diet on FA profile, leading to higher SFA and MUFA contents. Meat colour, TBARS value and conjugated dienes were not affected by the tannin supplementation and it can be concluded that dietary chestnut hydrolysable tannins didn\u2019t improve the colour and oxidative stability of the rabhit meat