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Made available in DSpace on 2022-05-01T05:29:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-06-07 This study aimed to estimate the protein requirements for the maintenance of growing Saanen goats of different sexes from 5 to 45 kg of body weight (BW) using two methods and applying a meta-analysis. For this purpose, two datasets were used. One dataset was used to evaluate the effects of sex on the protein requirements for maintenance using the comparative slaughter technique. This dataset was composed of 185 individual records (80 intact males, 62 castrated males, and 43 females) from six studies. The other dataset was used to evaluate the effects of sex on the protein requirements for maintenance using the N balance method. This dataset was composed of 136 individual records (59 intact males, 43 castrated males, and 34 females) from six studies. All studies applied an experimental design that provided different levels of N intake and different levels of N retention, allowing the development of regression equations to predict the net protein requirement for maintenance (NPM) and the metabolizable protein (MP) requirements for maintenance (MPM) in Saanen goats. The efficiency of MP use for maintenance (kPM) was computed as NPM/MPM. The efficiency of MP use for gain (kPG) was calculated using the equation of daily protein retained against daily MP intake above maintenance. A meta-analysis was applied using the MIXED procedure of SAS, in which sex was considered a fixed effect, and blocks nested in the studies and goat sex were considered as random effects. The NPM did not differ between sexes, irrespective of the approach used. The daily NPM estimated was 1.23 g/kg0.75 BW when using the comparative slaughter technique, while it was 3.18 g/kg0.75 BW when using the N balance technique for growing Saanen goats. The MPM estimated was 3.8 g/kg0.75 BW, the kPM was 0.33, and the kPG was 0.52. We observed that the NPM when using the comparative slaughter technique in growing Saanen goats is lower than that recommended by the current small ruminant feeding systems; on the other hand, the MPM was similar to previous reports by the feeding systems. Sex did not affect the protein requirements for maintenance and the efficiencies of use of metabolizable protein. Department of Animal Sciences Universidade Estadual Paulista Institute of Studies of the Humid Tropic Universidade Federal do Sul e Sudeste do Pará Department of Animal Science Universidade Federal Rural da Amazônia University of New England Department of Animal Sciences Universidade Estadual Paulista

Made available in DSpace on 2020-12-12T02:38:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-05-01 Asociación Universitaria Iberoamericana de Postgrado Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The objective of this study was to evaluate the effects of sex on the daily net requirements of calcium (NCam), phosphorus (NPm), potassium (NKm), and magnesium (NMgm) for maintenance in Saanen goats from 5 to 45 kg BW. Two datasets were used: the first dataset was composed of 154 individual records (53 castrated males, 46 females, and 55 intact males) from three studies, and was used to estimate the NCam, NPm, NKm, and NMgm using the comparative slaughter technique (CST). The second dataset was assembled from 160 individual records (67 castrated males, 45 females, and 48 intact males) from four feeding trials, and was used to estimate the NCam, NKm, and NMgm in Saanen goats, using the minimum endogenous losses method (MEL). A meta-analytic approach was applied using a mixed model, in which sex was considered a fixed effect and study a random effect. Using the CST, the results revealed that sex did not affect NCam, NPm, or NKm (21.1, 22.8, and 4.0 mg/kg BW, respectively; P > 0.10), but NMgm of intact males was greater than for castrated males or females (2.6 versus 1.4 mg/kg BW; P = 0.077). On the other hand, sex did not affect the NCam, NKm, or NMgm (38.0, 25.2, and 7.4 mg/kg BW, respectively; P > 0.10), when MEL was used. The findings of this study suggest that Ca, P, and K requirements for maintenance in goats are not influenced by sex. Conversely, Mg requirement for maintenance should be discriminated by sex. Also, that P requirements for maintenance were significantly lower than current feeding system recommendations. Department of Animal Science UNESP - Universidade Estadual Paulista School of Environmental and Rural Science University of New England Department of Animal Science UNESP - Universidade Estadual Paulista Asociación Universitaria Iberoamericana de Postgrado: 1 Asociación Universitaria Iberoamericana de Postgrado: 166754 FAPESP: 2014/14734 FAPESP: 9

Made available in DSpace on 2019-10-04T12:33:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01. Added 1 bitstream(s) on 2019-10-09T18:33:45Z : No. of bitstreams: 1 S1516-35982018000100618.pdf: 561491 bytes, checksum: a2ca38f27714aef67bc8f7426fee863e (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Asociacion Universitaria Iberoamericana de Postgrado (AUIP) The objective of this study was to investigate the multivariate relationship among body protein, fat, and macrominerals in Saanen goats of different sexes (castrated males, females, and intact males) using canonical correlation analysis. Individual records of 274 Saanen goats combined from 10 studies was used. Two sets of body constituents were established: the first one contained variables related to body protein or fat (canonical variate U) and the second contained variables related to body calcium, phosphorus, magnesium, sodium, or potassium (canonical variate V). Two canonical pairs were identified for each sex. However, irrespective of sex, first canonical pairs accounted for more than 87% of variance of the dependent variables, these only being used for the analysis. For canonical variate U 1, canonical weights for protein were greater than that for fat (in castrated males, protein = 0.62 and fat = 0.41; in females, protein = 0.96 and fat = 0.039; and in intact males, protein = 0.81 and fat = 0.20). For canonical variate V 1, in males, the highest canonical weights were for potassium and phosphorus, whereas the lowest were for calcium (in castrated males, potassium = 0.485 > phosphorus = 0.259 > magnesium = 0.206 > sodium = 0.129 > calcium = 0.081, and in intact males, potassium = 0.499 > phosphorus = 0.459 > sodium = 0.105 > magnesium = 0.024 > calcium = 0.001). On the other hand, in females, the highest canonical weights were for potassium and calcium, whereas the lowest was for magnesium (potassium = 0.539 > calcium = 0.201 > phosphorus = 0.178 > sodium = 0.088 > magnesium = 0.081). The current results may help to understand the role of sex on strength and nature of the association among body protein, fat, and macrominerals in growing Saanen goats. Univ Estadual Paulista, Dept Zootecnia, Jaboticabal, SP, Brazil Univ Estadual Paulista, Dept Zootecnia, Jaboticabal, SP, Brazil FAPESP: 2014/14734-9 Asociacion Universitaria Iberoamericana de Postgrado (AUIP): 166754-1