The objective was to evaluate the effects of genetic group and age on growth, carcass, and meattraits of rabbits. A total of 144 straightbred Botucatu and White German Giant  × Botucatu crossbred rabbitswere involved. Rabbits were weaned at 35 d and sequentially slaughtered, four per genetic group  × sexcombination, at: 42, 49, 56, 63, 70, 77, 84 and 91 d. A 2×2 factorial arrangement was employed in a completelyrandomized design with repeated measures for growth traits, and a split-plot for carcass and meat traits.Crossbred rabbits were heavier (2032 vs. 1962 g; P<0.01), consumed more feed (143.5 vs. 131.0 g/d; P<0.01),and presented higher slaughter weight (2169  vs. 2093 g; P=0.02) and dressing percentage (59.0  vs. 58.2%;P=0.07) than straightbreds throughout the experiment. No difference between genetic groups was detectedfor feed conversion and empty gastrointestinal weight corrected for slaughter weight (SW). Crossbredsshowed higher skin weight (308.2 vs. 299.7 g; P=0.06) and distal parts of leg weight (75.7 vs. 71.4 g; P<0.01),both corrected for SW. No genetic group effect was detected on dissectible fat and hind part weights. Chilledcommercial carcass (1284 vs. 1229 g; P=0.02), chilled reference carcass (1036 vs. 1000 g; P=0.06), fore part(297.9 vs. 283.3 g; P=0.01) and loin (308.7 vs. 295.5 g; P=0.05) were heavier in crossbreds than in straightbreds,but these differences were attributed to differences in SW. Uncorrected weights of head, kidneys, liver andthoracic viscera were higher in the crossbred group, but only head (116.6  vs. 113.6 g; P=0.06) and thoracicviscera (30.4 vs. 28.6 g; P=0.01) were, in fact, proportionately heavier in crossbreds than in straightbreds. Noeffect of genetic group was detected on meat to bone ratio, muscle ultimate pH and chemical composition of theLongissimus dorsi muscle. All traits, except for ash and fat contents of the Longissimus muscle, showed ageeffects (P<0.01). Crossbreeding may be recommended for the production of whole commercial carcasses, butit is not clearly advantageous for the production of retail cuts. Slaughter should take place between 63 and 70d of age for both genetic groups.

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Growth, carcass and meat quality traits of straightbred and crossbred botucatu rabbits

Effect of different dietary ratios of sunflower and linseed oils on growth and carcass traits of rabbits

As in other livestock species, the annual per capita consumption of rabbit meat is currently estimated as the ratio of the total weight of carcasses available for consumption to the number of inhabitants of a certain region. The aim of this work was to establish conversion coefficients from carcass to dible lean meat and estimate real rabbit meat consumption in Italy. Accordingly, a total of 24 rabbits were slaughtered at 2 different ages to obtain carcasses representative of the main market categories in Northern Italy: medium-size (carcass weight of about 1.4 kg) and heavy-size (carcass weight of about 1.8 kg). Chilled carcasses were used to determine offal, dissectible fat, bone and meat weights and yields. Experimentally obtained conversion factors from carcass to edible lean meat and estimated meat waste percentage at retail and consumption levels were subsequently used to estimate the real per capita amount of rabbit meat consumed in Italy. The finding of this study revealed that, if compared to the medium-size group, heavy-size carcasses had higher lean meat yield for both intermediate (92.9 vs. 92.4%; P<0.05) and hind parts (84.3 vs. 79.1%; P<0.001). On the contrary, the meat yield of fore part was higher in the medium-size group (66.2 vs. 65.5%; P<0.001) compared to heavy-size carcasses. Eventually, overall meat yield was higher in heavy-size carcasses compared to medium-size ones (64.4 vs. 63.2%; P<0.001). By using these conversion factors and estimated overall losses at retailing and home-consumption (15%), we estimated that real per capita annual rabbit meat consumption is 0.50 kg in Italy, which is only 54% compared to the estimated apparent consumption (0.90 kg).

https://polipapers.upv.es/index.php/wrs/article/download/7802/9746

Technical note: Estimation of real rabbit meat consumption in Italy

Two experiments were done to study the effect of partial replacement of berseem hay by ensiled and dried sugar beet tops on the performance of growing rabbits. In the first one, 8 mature male NZW rabbits with an average body weight of 2.5 kg and 8 months old were used to determine digestibility coefficients and nutritive values of berseem hay (BH), ensiled sugar beet tops (SBTS) and dried sugar beet tops (SBTH). In the second one, 50 NZW growing rabbits of 60 days of age were used in a complete randomized design experiment with five treatments. The first group fed commercial rabbit diet including 40% BH (control diet), while in the other groups 50 or 100% of BH was replaced by SBTS and SBTH throughout the 70 days of experiment. Results of the first experiment showed that the contents of OM and CF were lower and NFE and ash content were higher in SBTS and SBTH compared with of BH. While, CP was higher in SBTS and lower in SBTH than that of BH. The digestibility coefficients of DM, OM, CF, EE and NFE were significantly higher (P<0.05) for both SBTS and SBTH compared with BH. However, BH had significantly (P<0.05) the highest TDN and DE values followed by SBTS, while SBTH had the lowest values. While, CP digestibility and DCP value of SBTS were significantly higher (P<0.05) than that of BH and SBTH. In the second experiment showed that calculated composition was nearly similar for the different diets except OM and CF decreased and ash increased in diets contained SBTS and SBTH compared with commercial diet. Diet contained 100% SBTS showed significantly (P<0.05) the highest digestibility coefficients of DM, OM, CP, EE and NFE and DCP value. While, commercial diet revealed the highest CF digestibility and TDN and DE values. Rabbits fed 100% SBTS diet had the highest TVFA's and NH3-N concentrations and the lowest pH value. Rabbits fed 100% SBTS diet showed significantly (P<0.05) the highest final body weight, total and daily weight gain and the lowest average daily and total DM intake and DM/kg gain, however, those fed commercial diet had the opposite trend. Rabbits fed commercial diet showed significantly (P<0.05) the highest feed cost and feed cost/kg gain, however, rabbits fed 100% SBTS diet showed significantly (P<0.05) the highest total and net revenue and net revenue improvement. Rabbits fed 100% SBTS showed significantly (P<0.05) the highest slaughter weight, carcass weight, dressing percentage, meat weight and percentage and the contents of CP, EE and ash and lowest DM content in meat, but, those fed commercial diet had the opposite trend. (Researcher. 2010;2(9):10-15). (ISSN: 1553- 9865).

Effect Of Partial Replacement Of Berseem Hay By Ensiled And Dried Sugar Beet Tops On Performance Of Growing Rabbits

Avaliaram-se o desempenho, as caracteristicas de carcaca e a viabilidade economica de coelhos sexados abatidos em diferentes idades. Foram usados 100 coelhos (50 machos e 50 femeas), em delineamento de blocos inteiramente ao acaso e arranjo fatorial 2×2 (dois sexos e duas idades ao abate), com quatro tratamentos e cinco repeticoes. Os coelhos foram desmamados aos 35 e abatidos aos 75 ou 90 dias de idade. Nao houve diferenca entre sexo (P>0,05) nos parâmetros avaliados. Os animais abatidos aos 90 dias (P<0,001) eram mais pesados e consumiram (diario) mais racao. Os abatidos aos 75 dias (P<0,001) ganharam mais peso (diario) e apresentaram melhor conversao alimentar. Coelhos abatidos aos 90 dias de idade tiveram maiores pesos relativos de carcaca (P<0,04), de coxa (P<0,001), de gordura interna (P<0,001) e de figado (P<0,01) e, ainda, apresentaram maior peso final e melhores caracteristicas de carcaca, cuja venda foi mais lucrativa quando realizada aos 75 dias ou quando foram abatidos aos 90 dias de idade.

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Desempenho, características de carcaça e viabilidade econômica de coelhos sexados abatidos em diferentes idades

For 267 Pannon White growing rabbits of both sexes slaughtered at a body weight of 2.2-2.4, 2.4-2.6, 2.6-2.8, 2.8-3.0, 3.0-3.2, 3.2-3.4 and 3.4-3.5 kg, the average dressing percentage was 59.5, 60.7, 61.9, 62.2, 61.4, 62.4 and 62.1 % respectively. While the weight of live animals increased by about 50 % between 2.29 and 3.42 kg the change in the weight of blood (23 %), full gastrointestinal tract (26 %) and head (35 %) were the lowest, whereas the intermediate part (65 %), liver (82 %), skin (73 %), meat on hind legs (74 %), meat on the intermediate part (85 %) and perirenal fat (326 %) gained weight the most rapidly. 129 Pannon White rabbits were slaughtered between 2.2 and 3.5 kg live weight. The water, protein, fat and ash content of their meat was analyzed in the M. longissimus dorsi (LD), hind leg (HL) and M. /ongissimus dorsi + belly (LD + B). Water content averaged 74.8, 73.8 and 71.0 % in LD, HL and LD + B respectively, whereas protein, fat and ash content averaged 23.1, 22.1 and 21.7 %, 1.08, 3.24 and 6.39 %, 1.15, 1.09 and 1.04 % respectively, in the arder of the meat parts Usted above. Water content decreased and fat content increased with increasing weight (r = -0.47, -0.33 and -0.51, r = 0.38, 0.31 and 0.45 for water and fat contents of LD, HL and LD + B respectively). Protein and ash content did not change significantly with weight.

https://polipapers.upv.es/index.php/wrs/article/download/351/338

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Papers

The effect of live weight on the carcass traits and the chemical composition of meat of pannon white rabbits between 2.2 and 3.5 kgs.