-The objective of this study was to evaluate the association of forage cactus with different fiber sources (elephant grass hay -EGH; corn straw -CS, hay of cassava shoots -HCS; fresh sugarcane bagasse -FSB; and hydrolyzed sugarcane bagasse -HSB) on the milk yield and composition and the feeding behavior of lactating Sindhi cows. Five cows with average body weight, average daily milk yield, and average daily 4%-fat-corrected milk yield of 265, 4.95 and 5.22 kg, respectively, were used in a 5 × 5 Latin square design. The effect of experimental diets on milk yield and composition, feeding time (FT), rumination time (RT), idle time, mean values of total chewing time (TCT), number of ruminal boli (NRB), number of rumination chews (NRC), and feed efficiency (FE) and rumination efficiency (RE) expressed as a function of DM and NDF were analyzed. Milk yield in kg/day and corrected to 4.0% fat from the animals that received cactus associated with CS were higher as compared with the treatment with hydrolyzed sugarcane bagasse. The milk composition variables were not influenced by the treatments, and nor were FT, RT, TCT, NRB and NC. Two patterns were observed for FE and RE, with higher efficiency of the diets with EGH, CS and HCS and lower efficiency for diets containing sugarcane bagasse. In this context, Sindhi cows fed forage cactus associated with corn straw, elephant grass hay, and hay of cassava shoots present better performance, feeding efficiency, and rumination responses than those fed forage cactus associated with fresh sugarcane bagasse and hydrolyzed sugarcane bagasse.
This study characterized the thermal environment and assessed the physiological aspects of acclimatization of Sindhi and Guzerat heifers in a tropical environment (Brazil) under shade. Eight Sindhi and eight Guzerat purebred heifers (Bos indicus) had their physiological traits measured twice a day (9:00 a.m. and 2:00 p.m.). Environmental data during the experimental period were collected at two-hour intervals between 5:00 a.m. and 5:00 p.m. The temperature-humidity (THI) and the black globe temperature-humidity (BGHI) indices were calculated, and surface temperature (S t ), respiratory rate (R r ), and rectal temperature (R t ) were collected, being used to estimate heat loss by cutaneous (E c ) and respiratory (E r ) evaporation. In the warmer parts of the day (1:00 and 3:00 p.m.), the THI and BGHI reached values of 80.26 and 81.25, respectively. There was no significant difference in rectal temperatures between the breeds, but higher values were observed in the afternoon. Heat transfer by cutaneous evaporation reached 118.71±12.91 W.m -2 and 103.43±6.82 W.m -2 at 2:00 p.m. for the Sindhi and Guzerat heifers, respectively. Under these conditions (air temperature was between 29 and 30°C), 84% of the total latent heat loss in Sindhi and Guzerat heifers was represented by E c . It can be concluded that Sindhi and Guzerat heifers can maintain homeothermy with minimal thermoregulatory effort under shade conditions in a tropical environment.
Este estudo teve por objetivo avaliar o efeito da prevalência de patógenos causadores de mastite e da contagem de células somáticas (CCS) sobre a produção e composição do leite. Amostras de leite de 1163 vacas da raça Holandesa com 30.97±10.22 kg·d-1 de produção de leite foram coletadas e avaliadas. Staphylococcus spp. foi o patógeno mais prevalente. No geral, o aumento da CCS reduziu a produção de leite e a concentração de lactose e aumentou a concentração de proteína. Coliformes tiveram uma relação diferente entre CCS e teor de proteína no leite. A relação entre CCS e concentração de lactose foi diferente para S. aureus e Streptococcus spp. Lactose e proteína bruta são os componentes do leite mais sensíveis à variação da CCS e esta relação é dependente da presença do patógeno.
The objective of this study was to evaluate the production, fat and fatty acids of milk as well as the diameter, classification and quantity of the milk fat globules (MFG) of goats consuming a diet with 15% of crude glycerin. Twelve multiparous Saanen goats weighing 40 ± 6 kg and 90 ± 5 days of lactation were used. The experimental design was completely randomized with two treatments (0 and 15% inclusion of glycerin). In this way, each milk sample is classified according to the percentage of milk fat globules that were included in these three size categories. For the variables milk production, fat, diameter, medium and large fat globules and amount of globules showed a significant effect of the inclusion of glycerin in the diet (p < 0.05). Fifteen fatty acids were found, mostly saturated. For caprylic, palmitic, and linoleic fatty acids, there was no significant influence of the inclusion of glycerin (p > 0.05). Can recommend the use of 15% double-distilled glycerin in the feeding of lactating goats increased milk production, the amount of fat, increased the size of the milk fat globule. Regarding the saturated and polyunsaturated fatty acids, they kept the level of 15% of glycerin.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.