Forty-two springer Holstein heifers were grouped in threes by sire, body weight, and due date. One of each group served as a control (no exercise). One of each group was exercised at 5.5 kilometers per hour for 1.6 kilometers per day, 5 days per week beginning 4 weeks before expected calving date . The third member of each group was exercised the same as the second member, but exercise was continued for 10 days after calving. Exercise was in a circular lane with a motor driven gate. Prepartum exercise increased ease of parturition and reduced the length of time from calving to release of the placenta. Exercise resulted in smaller uterine horn diameters at 42 days postpartum, but had no significant effect on measures of fertility such as days open or services per conception . Exercise did not appear to reduce severity of udder edema, but edema was first noticeable in control heifers. Milk production for the first 50 days after calving showed no affect from prepartum exercise, but continuing exercise after calving reduced milk production 2.4 kg per day (P< .05). Grain was fed according to production, hence grain consumption was also significantly lower for the postpartum exercise group. Hay consumption for the prepartum exercise group was significantly lower than for controls. Prepartum exercise significantly increased feed utilization efficiency as compared to postpartum exercise.

Mechanically pressed Brassica napus L. meals’ digestibility nutritional compositions were evaluated with digestibility studies. Two growth trials were conducted identifying the meals’ maximum dietary inclusion level in broiler chicken diets. Heat reduced nutrient digestibility of mechanically pressed black canola meal (MPBCM). Meals with higher residual oil had higher AMEn. Enzyme addition did not affect MPBCM AMEn but increased standardized ileal amino acid digestibility (SIAAD) of meal with high residual oil. Carbohydrase increased AMEn of mechanically pressed yellow canola meal (MPYCM) while lipase generally improved SIAAD. MPBCM with 12 and 17% residual oil can be fed up 15% in the starter and grower diets but at 10% in finisher diet. Mechanically pressed black canola meal (MPYCM) with 12% residual oil should be fed in the starter and finisher diets at 10% and 15% in grower diet. Meal with 17% residual oil should be fed only at 10% in finisher diet. / Masters Thesis

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.

Made available in DSpace on 2014-08-20T14:38:43Z (GMT). No. of bitstreams: 1 Dissertacao_Marcelo_Giordano_Nunes.pdf: 393789 bytes, checksum: 9db8a83e720caee57a341f49cc6c5498 (MD5) Previous issue date: 2011-03-31 / The objective of this study was to evaluate feed efficiency and carcass and beef quality of pure and crossbred genotypes, as well as the possible influence of the finishing system on the beef physical-chemical and sensory traits. Steers of six different genotypes, Aberdeen Angus (ANAN), Hereford (HHHH), Nellore (NENE), Aberdeen Angus x Nellore (ANNE), Aberdenn Angus x Hereford (ANHH) and Aberdeen Angus X Caracu (ANCR) were evaluated during finishing in two different systems: feedlot or cultivated pasture. The steers entered the finishing with an average age of 19.8 ± 0.91 months. Animals kept in feedlot received a diet containing 40% concentrate and 60% of forage on a dry matter basis. The roughages used were corn and sorghum silage mixed in 50:50 ratio. All supplied feed and the leftovers were weighed daily to estimate daily intake of confined steers. Cattle finished on pasture was kept in a paddock with cultivated oats and ryegrass. The slaughter criterion was a subcutaneous fat thickness of at least 3 mm, measured at the weighing days by ultrasound. Significant differences in feed efficiency were found between studied genotypes. The animals of HHHH breed group were superior to the ANAN and NENE animals in the residual feed intake evaluation obtaining the respective values of -0.92 kg versus 0.73 and 0.70 kg. For feed conversion the HHHH shower a smaller amount of feed intake per kilogram of weight gain when compared to ANNE, ANCR and NENE (6.0 vs. 9.4, 8.5 and 10.9 kg, respectively). The HHHH had the lowest dry matter intake, 7.4 kg, and did not differ only of the NENE (8.5 kg). It was observed a smaller slaughter weight in the NENE (403 kg), while ANNE and ANCR animals showed higher values for chilled carcass weight (272 and 256 kg, respectively). In assessing the primary cuts of the carcass, the NENE presented the lowest rib weight, 14 kg, when compared to others genotypes. Regarding beef quality, the ANCR breed group presented tenderer steaks than ANNE and NENE groups in the evaluation of shear force (3.7 vs 5.9 e 6.9kgf, respectively). In sensory toughness attribute, the beef of ANCR, ANHH and HHHH animals was considered tenderer than NENE animals. Caracu breed can be used as an alternative to zebu in crossing with British breeds showing comparable levels in quantitative aspects of carcass, but with higher beef tenderness when compared to zebu breeds. In this experiment conditions, the NENE showed low productivity and also poor beef and carcass quality; nevertheless, it had superior performance in the crossbreeding with Aberdeen Angus. / O objetivo deste estudo foi avaliar a eficiência alimentar e a qualidade da carcaça e da carne de diferentes genótipos puros e cruzados, bem como a possível influência do sistema de terminação nas características físicoquímicas e sensórias da carne bovina. Para isso, utilizou-se novilhos de seis diferentes genótipos, Aberdeen Angus (ANAN), Hereford (HHHH), Nelore (NENE), Aberdeen Angus X Nelore (ANNE), Aberdeen Angus X Hereford (ANHH) e Aberdeen Angus X Caracu (ANCR), terminados em dois diferentes sistemas: confinamento intensivo ou pastagem cultivada. Os novilhos entraram na terminação com idade média de 19,8±0,91 meses. Os animais mantidos em sistema de confinamento receberam dieta composta por 40% de concentrado e 60% de volumoso com base na matéria seca. Como volumosos foram utilizados silagem de milho e sorgo misturados em proporção de 50:50. O gado terminado em pastagem foi mantido em potreiro consorciado com aveia e azevém. O critério utilizado para abate foi à espessura de gordura subcutânea mínima de 3 mm, mensurada junto com as pesagens por avaliações de ultrasonografia. Foram encontradas diferenças significativas de eficiência alimentar entre os genótipos estudados. Os animais do grupo racial HHHH apresentaram melhor eficiência que os ANAN e NENE na avaliação de consumo alimentar residual obtendo respectivos valores de -0,92 kg vs. 0,73 e 0,70 kg. Para a conversão alimentar, o HHHH apresentou menor quantidade de alimento consumido por quilograma de ganho de peso quando comparado aos ANNE, ANCR e NENE (6,0 vs. 9,4, 8,5 e 10,9 kg, respectivamente). O HHHH também apresentou o menor consumo de matéria seca, 7,4 kg, não diferindo (P>0,05) apenas do NENE com 8,5 kg. Observou-se menor peso vivo ao abate nos animais NENE (403 kg), enquanto os animais ANNE e ANCR apresentaram os maiores valores para peso de carcaça fria (272 e 256 kg, respectivamente). Na avaliação dos cortes primários da carcaça, o NENE apresentou peso de costela mais leve quando comparado aos demais (14 kg). Quanto à qualidade da carne, o grupo ANCR apresentou carne mais macia que os grupos ANNE e NENE na avaliação de força de cisalhamento pelo método instrumental (3,7 vs. 5,9 e 6,9 kgf, respectivamente). Sendo que na avaliação sensorial para o atributo dureza, a carne dos animais ANCR, ANHH e HHHH foi considerada mais macia que de animais NENE. A raça Caracu pode ser usada com alternativa ao zebu no cruzamento com raças britânicas apresentando níveis comparáveis quanto aos aspectos quantitativos da carcaça, mas com maior maciez da carne quando comparada com raças zebuínas. O genótipo NENE puro nas condições deste experimento apresentou baixa produtividade e também baixa qualidade de carne e carcaça, no entanto, teve desempenho superior no cruzamento com a raça Aberdeen Angus.

Text in English / The study was conducted in two different types of natural ventilated housing systems; one featured with conventional laying cages while other had free-range system features. The aim was to analyse productivity and economic benefit or loss of the Lohmann Brown Lite on different housing (Free-range system and Conventional cage system) with an evaluation of production cost. The total of 49 700 point of lay Lohmann Brown Lite layers pullets were placed in four natural ventilation free-range houses each consist of three rows of two tier conventional laying cages. The other 40 000 point of lay Lohmann Brown Lite layers pullets were place in four free-range houses each with placement of 10 000 chickens. The Cobb Douglas production model was used to determine the productivity of two different housing system by factoring the fixed cost and variable cost of the entire production process. The breakeven point tool was used to analyse the point where the total revenue equals the total variable and fixed expenses and the cost volume profit by measuring the profitability of each housing system (Nabil et al. 2014). The results of the study revealed different productivity between conventional cage system (82.94%) and the free-range system (77.46%). These results led to the acceptance of hypothesis 1 that “the production of Lohmann Brown Lite is the same when they are kept on the free-range system or conventional cage system. The capital investment and operation on conventional cage system showed breakeven at 43 months while free-range system showed breakeven at 60 months. The economic benefit analysis shows that the free-range system has cost benefit of R0.29 and conventional cage system has a cost benefit of R0.26. It means for every rand spent, farmer may get R0.29 Rand as profit for free-range system and every rand spent for conventional cage system can get R0.26 Rand. The economic benefit to farmer is greater on free-range system that lead to acceptance of hypothesis 2 that the economic benefit of egg production is greater on the free-range system compared to conventional cage system. Free-range housing system remain the best alternative to replace the conventional cage housing system. / Agriculture and  Animal Health / M.Sc. (Agriculture)