The effect of climatic factors on ovarian activity and reproductive behavior (RB) was evaluated in 46 Bos indicus cows kept under grazing conditions. Temperature-humidity index (THI) was used as an indicator of stress and divided in alert, damage and emergency levels. Fat thickness (FAT) was taken during the last trimester of gestation (LTG) to approximately 90d postpartum (PP). At 30d PP animals received a progesterone (P4)-releasing device (CIDR) which was withdrawn 9d later. Ovarian activity was assessed by blood progesterone on days 21, 24, 27, 30, 49, 51, and 54 PP. Animals were divided into three groups, higher, and moderate RB and non-behavior. Sixty percent presented a THI >74 increasing dramatically from June to September up to >78. During LTG, animals lost 27% of their body reserves contrasting to PP where an increase of 2.6% (P=0.002) was observed. The percentages of cyclic and non-cyclic animals were 57 and 43%, respectively (P> 0.05). Seventy-two percent displayed RB and 28% were non-behavior (P<0.05). A negative correlation (r =-0.307; P = 0.038) between THI and RB, and a positive correlation (r = 0.427; P = 0.003) between the onset of ovarian activity and RB were observed. Differences in THI during the LTG (P<0.01) were observed between cyclic and non-cyclic animals. Non-behavior cows in the LTG had a higher THI (P <0.05). High levels of THI have a negative effect on the resumption of ovarian activity and RB in Bos indicus especially if high THI occurs during the last trimester of gestation.
Effect of storage time and processing temperature of grains with added amylolytic enzymes on in situ ruminal starch digestion. J. Appl. h i m. Res., 27: 39-44. Amylolytic exogenous enzymes may increase ruminal digestion of grains. However, stability of enzymes during feed processing can be a constraint for its utilization. Therefore, the objective of this study was to evaluate the efficacy of B. licheniformis amylase and A. n i e r glucoamylase, according to time of storage after treatment and duration of exposition at 100 C, usirtg corn and sorghum and its effect on in situ ruminal digestibility (12 h incubation) of dry matter and starch. A generalized randomized complete block design was used i n the assays, using the block x treatment interaction as the error term. Ruminal starch digestibility (%) was not affected by either time (1, 4, 7, 15 and 30 days) of aspersion before incubation or by the time (0.5, 3, 5, 10 and 15 min) of enzyme exposition at 100 C. It was concluded that both amylolytic thermostable enzymes have the potential as a feed additive to improve ruminal digestibility of corn and sorghum, and are stable at low humidity conditions, which may facilitate its incorporation with grains during feed processing.
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.