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Item Fatores que influenciam a produção de leite no período da seca e das águas(Revista Brasileira de Agropecuária Sustentável, 2023-12) Freitas, Luciano da Silva; Lana, Rogério de PaulaObjetivou-se com o presente trabalho analisar os indicadores de produção de 32 fazendas na região de Viçosa-MG bem como um estudo da influência desses indicadores no aumento da produção diária de leite em nível de fazenda. Para efeito de determinação e análise coletou-se dados referentes à produção total diária, produção total mensal, número de vacas em lactação, número total de vacas do rebanho e área destinada à pecuária de leite em duas estações do ano: período de menor incidência de chuva, período seco, e o período com maior incidência de chuvas, período das águas. Para tanto foi observado através de análises estatística que em nível de fazenda o aumento da produção diária de leite em qualquer das duas estações do ano está correlacionado diretamente com o aumento do número de animais ordenhados seguido pelo aumento da área destinada à pecuária e por fim com o aumento da produtividade por animal.Item Evaluation of organic salts on the performance of dairy crossbred milking cows and growing animals on pasture(Revista Brasileira de Agropecuária Sustentável, 2022-09) Lana, Rogério de Paula; Souza, Wallace de Castro; Pereira, Lucas Bastos; Rosa, Ricardo OliveiraThe use of additives in ruminant diets has occurred more intensely in recent years to increase animal performance, through changes in the ruminal microbiota. Thus, this study aimed to evaluate: 1) the use of Isomix (Iso) and virginiamycin (Vir) in concentrate, in a 2x2 factorial (without and with 30 g of Isomix/cow/day; without and with 210 mg of virginiamycin/cow/day), on the productive performance of mixed cows on pasture; 2) the use Isomix in multiple supplement (without and with 30 g of Isomix/animal/day), on the productive performance of pasture growing dairy mixed animals; and 3) the use Isomix in concentrate, at an increasing level (without and with 30, 60 or 90 g of Isomix/cow/day), on the productive performance of crossbred cows on pasture in the wet season. The work was conducted at Fazenda Boa Vista, district of Cachoeira de Santa Cruz, Viçosa, MG, and belonging to the Federal University of Viçosa. In experiment 1, there was no significant effect of the additives in the concentrate on milk production in cows producing 13.4 kg of milk/day in tropical pasture during the wet season, and more production research and nutritional parameters were required under these conditions. In experiment 2, there was an effect of Isomix on body weight gain, and therefore, the use of this additive in multiple supplements is recommended to improve the performance of growing cattle in the wet season, depending on the cost-benefit ratio with supplementation. In experiment 3, there was no significant effect of Isomix on the concentrate on milk production in cows producing 6.8 kg of milk/day, with presence of calves during milking, in tropical pasture of the wet season, but there was a tendency to increase fat, protein and lactose contents with the use of Isomix, being a possible benefit from the use of that additive.Item Influence of light intensity, preharvest fasting, and storage time on biochemical components in serum and plasma of broilers(Brazilian Journal of Animal Science, 2025-01) Polese, Clauber; Wachholz, Lucas; Souza, Cleison de; Rohloff Junior, Nilton; Tesser, Guilherme Luis Silva; Nunes, Rayanne Andrade; Eyng, Cinthia; Starkey, Jessica Dawn; Starkey, Charles William; Genova, Jansller Luiz; Nunes, Ricardo ViannaWe determined the impacts of light intensity, fasting, and storage times on total protein (TP), albumin (ALB), globulin (Glb), uric acid (UA), creatinine (Cre), calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) in serum and plasma of broilers. At 42 days old, 140 broilers (3,123 ± 654 g) were assigned to two light intensities (5 or 20 lux m−2) and seven fasting times (0, 2, 4, 6, 8, 10, and 12 h). At 45 days old, blood collection was performed in all the broilers. Serum and plasma were stored in a freezer at −20 °C and analyzed on 0, 15, 30, 60, and 120 days. Higher concentrations of Cre and plasma Ca were observed at 20 lux, while the other components were observed at 5 lux. Serum ALB and Ca decreased with each hour of fasting, whereas ALP increased. Uric acid had the lowest concentration at 4 h and 51 min of fasting. Peak serum concentrations of Glb, TP, and Cre were at 6 h, 4 h and 30 min, and 5 h and 15 min of fasting, respectively. Plasma UA, Ca, and P had the lowest concentration at 3 h and 48 min, 5 h and 45 min, and 30 min of fasting, respectively, and a reduction in ALP. Serum UA, TP, and Glb concentrations increased with increasing storage time. Peak serum concentrations of Cre, P, and Ca were at 42, 119, and lowest at 82 days, respectively. Plasma Glb and ALP showed an increase with each storage day, while Cre decreased. Plasma UA and P showed the highest concentrations at 101 and 62 days, respectively. Plasma Ca showed a lower concentration at 50 days. The factors studied significantly influence key blood components in broilers. Higher light intensity increases Cre and Ca concentrations, while fasting reduces serum ALB and Ca, with variable peaks in other components. Storage boosts serum UA, TP, and Glb, with component-specific peaks and declines over time.Item Economic viability analysis of mechanization in broiler chicken harvesting(Brazilian Journal of Animal Science, 2024-03-27) Dutra, Fábio Mascarenhas; Garcia, Rodrigo Garófallo; Noriller, Rafael Martins; Binotto, Erlaine; Burbarelli, Maria Fernanda de Castro; Komiyama, Claudia Marie; Caldara, Fabiana Ribeiro; Valentim, Jean KaiqueThis study aimed to analyze the economic viability of the implementation of a mechanized harvesting of broilers where the activity is carried out entirely manually. The viability indicators used were net present value (NPV), net future value (NFV), net uniform value (NUV), discounted payback (DP), and internal rate of return (IRR). Scenario analysis, sensitivity, and Monte Carlo simulation were performed in the present study. The results showed that the initial investment was US$ 1,868,302.76. The average price paid by the slaughterhouse to third-party manual harvesting companies was US$ 18.17 per thousand broilers, which was converted into revenue in the cash flow of the project. The cash flow result was positive at US$ 22,256.14 over the entire study period considering a daily catch of 144 thousand broilers. The results of the economic viability analysis were NPV of US$ 64,786.23, NFV of US$ 333,382.11, NUV of US$ 735.19, DP of 13.82 years, IRR of 0.965 monthly, and modified IRR of 0.933 monthly. These values prove the economic viability of implementing the project considering the market conditions at the time of the study. The analysis of scenarios showed great sensitivity to the exchange rate and the price of fuels. The Monte Carlo simulation highlighted a moderate risk of negative NPV, emphasizing the importance of considering this variable when making decisions. Despite these challenges, the potential benefits of mechanized harvesting, such as increased efficiency and reduced labor costs, make it a promising alternative to manual harvesting, even for small to medium-sized poultry industries.Item Housing conditions during the last month of gestation affect hoof health after calving in dairy heifers(Brazilian Journal of Animal Science, 2024-11-25) Akköse, Mehmet; İzci, CelalThis study evaluated the effects of housing in the last month of gestation on hoof health in postpartum dairy heifers. The hooves of the heifers were evaluated during functional claw trimming and lameness scoring at 30 days before the expected calving date, and only heifers without any hoof lesions and lameness were included in the study. The heifers were kept in cubicle housing systems with mats (MAT, n = 12), mattresses (MATR, n = 12) and solid concrete floors, and on a straw yard (SY, n = 12) without exposure to concrete during the last month of gestation. The effects of housing systems on hoof lesions and lameness were evaluated during functional claw trimming and locomotion scoring at 60 and 90 days in milk (DIM). The evaluation of hoof lesions with respect to the study group, time, and their interaction was performed with the general linear mixed model for repeated measures. All heifers displayed sole hemorrhages (SH), white-line hemorrhages (WLH), and heel horn erosion in the postpartum period, but none of the heifers displayed lameness. The mean SH severity score was significantly higher in groups MAT and MATR than in group SY (2.25, 1.92, 0.75, respectively) at 60 DIM, and significantly higher in group MAT than in groups MATR and SY (1.92, 0.92, 0.92, respectively) at 90 DIM. The mean WLH severity score was higher in group MAT than groups MATR and SY (1.92, 1.17, 0.92, respectively) at 60 DIM, and similar (0.83, 0.75, 0.50, respectively) at 90 DIM. Heel horn erosion did not differ in severity among the groups. Improving housing comfort during the last month of pregnancy significantly decreases the severity of postpartum SH and WLH.Item Effects of liquid delactosed permeate in nursery piglet diets: improvements in feed conversion with increased post-weaning diarrhea occurrence(Brazilian Journal of Animal Science, 2024-11-25) Vilela, Hellen Lazarino Oliveira; Martinelli, Gabriela Luiza; Silva, Bruna Vianna Garcia da; Trenkel, Andressa Luana Gorzelanski; Toledo, Damares de Castro Fidelis; Careli, Pedro Silva; Carvalho, Silvana Teixeira; Carvalho, Paulo Levi de Oliveira; Santos, Luan Sousa dos; Costa, Leandro Santos; Rocha, Gabriel Cipriano; Genova, Jansller LuizThe objective of this study was to assess the effects of liquid delactosed permeate (DLP) alone or mixed as baby feed with a conventional lactose-containing diet for nursery piglets on growth performance, diarrhea occurrence (DO), blood profile, gastrointestinal tract traits, and bacterial population counts. Ninety male hybrid piglets (7.59±0.63 kg) weaned at 25 days old (day 0) were assigned for 35 days in a complete block design based on body weight (BW) to one of three treatments: control diet (CD) containing lactose via whey permeate powder, supplied in mash and dry form, without DLP; supplemented diet (SD): CD + DLP provided in specific feeders and separated from the mash diet; moist diet (MD): CD moistened with DLP in a 1:1 ratio, 10 replicates, and three piglets per pen. Nursery phases were defined as pre-starter I and II (days 0 to 7, and 8 to 21) and starter (day 22 to 35). Piglets fed MD diet had better feed conversion (FCR) compared with those fed CD in the pre-starter I and II and total period. Piglets in pre-starter I fed MD diet had a higher DO compared with those fed CD, whereas piglets fed SD had intermediate results. Piglets in pre-starter II fed SD had a higher total protein concentration than those fed MD, and CD provided intermediate results. Piglets on MD had higher leukocyte concentrations compared with those fed CD, but piglets fed SD had intermediate results. Piglets fed CD or SD diets had higher colonic content pH than those fed MD. Piglets fed SD or MD diets had longer large intestine lengths than animals fed CD. Delactosed permeate improves FCR in piglets in the pre-starter phases and promotes minor changes in other variables; however, a greater DO is observed in the first few days post-weaning.Item Metabolizable energy levels and L-arginine supplementation in diets for broilers under heat stress from 29 to 42 days of age(Brazilian Journal of Animal Science, 2024-10-30) Oliveira, David Henrique de; Cruz, Fábio Loures; Sobrane Filho, Sérgio Turra; Alves, Breno Resende; Abreu, Márvio Lobão Teixeira de; Naves, Luciana de Paula; Rodrigues, Paulo BorgesThe objective of this study was to evaluate the L-arginine supplemental effects for broilers in the final rearing phase (29 and 42 days), during which they were exposed to heat stress and fed diets with different metabolizable energy levels. Performance, carcass parameters, and physiological and biochemical parameters related to lipid metabolism were evaluated. A completely randomized design was used, in a 3 × 2 factorial arrangement, corresponding to three metabolizable energy levels (3000, 3150, and 3300 kcal/kg) in diets supplemented or not with L-arginine (0.66%). Eight replicates composed by eight broilers each (experimental units; boxes) per treatment were evaluated, totaling 48 experimental units. Performance was evaluated in the period from 29 to 42 days old, and carcass and blood parameters were measured at 42 days old. L-arginine supplementation improved feed conversion and blood profile, mainly due to the reduction of total and LDL-cholesterol levels. Broilers that received 3300 kcal/kg of metabolizable energy showed the greatest weight gain, regardless of supplementation or not with arginine. The dietary supplementation with 0.66% of L-arginine for heat-stressed broilers can be recommended, regardless of the feed energy level.Item Meat sheep farming systems according to economic and productive indicators: a case study in Southern Brazil(Brazilian Journal of Animal Science, 2021-06) Debortoli, Elísio de Camargo; Monteiro, Alda Lúcia Gomes; Gameiro, Augusto Hauber; Saraiva, Livia Cristina Vale FidalgoThis study aimed to characterize 24 representative sheep production farms from five mesoregions in the state of Paraná, Southern Brazil, so that economic and productive improvement strategies could be proposed. The representative farms for each region were defined at meetings with sheep farmers and technicians via the rapid appraisal methodology and represent 65% of the state’s flock. The information of each representative farm was collected between March 2015 and February 2016. Principal component analysis was used to verify the relationships among the different variables that characterized the farms. These characteristics were: number of ewes (V1), total cost per kilogram of revenue-generating product (V2), feeding costs (V3), labor costs (V4), facility and equipment depreciation costs (V5), and gross margin in the production cycle (V6). Cluster analysis was performed, resulting in three distinct groups: one including eight, another seven, and the third, nine farms. The results aided in classifying the farms into groups with similar characteristics, such as production scale, reproductive efficiency, technical and managerial control, appreciation of cooperatives, and availability of continuous technical assistance. The production scale, reproductive and productive efficiency, adoption of technologies, and cooperative organizational structure can be emphasized as positive performance benchmarks and were the most important aspects to achieve positive economic results.Item Estimation of genetic parameters for weaning and yearling weights in a composite population used to form the Purunã breed(Brazilian Journal of Animal Science, 2021-06) Otto, Pamela Itajara; Santos, Alexandre Leseur dos; Perotto, Daniel; Oliveira, Sheila Nogueira de; Granzotto, Fernanda; Gobo, Diego Ortunio Rosa; Souza, Felipe Eduardo Zanão de; Thomazini, GuilhermeWe aimed to evaluate the effects of sex and the linear and quadratic components of age of dam at calving, as well as apply a mixed model including maternal effect for the genetic evaluation of weaning (WW) and yearling (YW) weights. The phenotypic database was composed by Charolais, Caracu, Aberdeen Angus, and Canchim purebred and crossbred animals. Single-trait analyses were performed using models that included the maternal effect for WW and YW traits, and a model ignoring this effect on YW (YWNM). The Deviance Information Criterion (DIC), model posterior probabilities (MPP), accuracy of breeding values (ACC), and Spearman’s rank correlation were applied to compare the models including and ignoring the maternal effect on YW. Sex and age of dam at calving had significant effects on WW and YW. The direct heritability estimates were 0.21±0.03 and 0.05±0.02, and the maternal heritabilities were 0.11±0.02 and 0.02±0.01 for WW and YW, respectively. The heritabilities estimated for YW may have been influenced by the several genetic groups in the population and by used conventional animal model, which may not have been the better fit model to evaluate YW in this population. The DIC, MPP, and ACC values indicated that YW outperformed the YWNM model, but the rank correlation and percentages of individuals selected in common suggested that the best animals would be selected independently of the model chosen.Item Effects of Acacia mearnsii De Wild. extract and monensin on intake, digestibility, and ruminal variables of lambs(Brazilian Journal of Animal Science, 2024) Ribeiro, Simone da Silva; Vedovatto, Marcelo; Palmer, Elizabeth Anne; Franco, Gumercindo LorianoThis study evaluated the effects of tannin extract of Acacia mearnsii De Wild. or monensin on intake, digestibility, nitrogen balance, and ruminal variables of lambs. Five rumen cannulated lambs (40.3 ± 2.8 kg) were used in a 5 × 5 Latin square design, with periods of 21 days each. The treatments were: control, without additive; Tan-0.60, Tan-1.20, and Tan-1.80 for the doses of 0.60, 1.20, and 1.80 g kg−1 body weight (BW) of tannin extract, respectively; and ionophore (monensin) at 0.75 mg kg−1 of BW. Tannins reduced the digestibility of dry matter (DM) and the greatest effects were observed for Tan-1.80. Tannins also increased or tended to increase the fecal excretion of DM, and the greatest effects were observed for Tan-1.20 and Tan-1.80. Tannins increased the fecal excretion of N, decreased the amount of N in urine, but did not affect N retained. Furthermore, tannins reduced the concentration of valerate and the acetate:propionate ratio and increased propionate without affecting the amount of total volatile fatty acids, and the greatest effects were observed for Tan-1.80. The use of ionophore only increased the elimination of N in the urine. Thus, monensin does not affect nitrogen retention, and tannin impairs digestibility, but increases propionate production.