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Simple Summary: The postpartum period is a metabolically stressful time for dairy cows. During this period, cows face suppressed feed intake and a series of stressors that challenge the cow's ability to adapt to lactation. Previous studies have shown that offering cows a total mixed ration diet containing a slowly fermentable starch source during the early postpartum period increases their feed intake when compared with that for a faster fermentable starch source. This leads to an immediate increase in milk production that carries over to later in lactation. These cows also exhibit an improved energy balance and decreased metabolic stress. However, the effects of feeding starch sources with differing fermentability during the early postpartum period in pasture-fed dairy systems are unknown. This experiment determined the effects of feeding starch sources with contrasting in vitro fermentability twice a day with perennial ryegrass silage as the forage source on feed intake, milk production, body reserves, feeding behavior, and markers of metabolic stress. This experiment determined the effects of two different starch sources when offered twice a day to cows during the early postpartum period (1 to 23 d postpartum, treatment period) on dry matter intake (DMI), feeding behavior, and milk production. The subsequent effects on milk production in the carryover period (24 to 72 d) where cows received a common diet (grazed perennial ryegrass pasture plus concentrate supplements) were also measured. Thirty-two multiparous dairy cows were offered concentrate feed (8 kg DM/d) containing 5 kg DM of crushed wheat grain or ground corn grain (7 h in vitro starch digestibility of 65.8% and 58.8%, respectively). At each milking (morning and afternoon), cows were offered half of the concentrate feed, and upon return to their individual stalls, they were offered perennial ryegrass pasture silage (56.2% neutral detergent fiber (NDF), 39.8% acid detergent fiber (ADF), 16.6% crude protein (CP)) at 130% of their expected daily intake. Dry matter intake, milk yield, and body weight were recorded daily. Blood and milk sampling, body condition score, and feeding behavior measurements were performed weekly during the treatment period. During the carryover period, milk sampling and body condition score measurements were conducted on a weekly and fortnightly basis, respectively. In the treatment and carryover periods, there was no significant effect of starch source treatment on DMI, milk yield, milk composition, change in body weight, or body condition. Similarly, the starch source did not affect the concentrations of blood markers of energy status or inflammatory response. Despite differences in the in vitro starch fermentability between treatments, the starch source did not significantly affect production responses. It is possible that the elevated NDF and ADF concentrations of the forage offered during the treatment period, the limited difference in starch fermentability between treatments, and the temporal supply of fuels to the liver when starch sources were offered twice a day may have offset the effects of the type of starch source on DMI and production via physical signals associated with rumen fill and distention. [ABSTRACT FROM AUTHOR]

Hurricane Harvey caused widespread flooding along the Texas Gulf Coast in August 2017; some areas of Houston received >150 cm of rainfall within a few days. Due to concerns over fecal contamination of floodwaters, surface water samples were collected at six locations in the southeastern Houston area immediately before and after the hurricane and then every 1 to 2 weeks thereafter over a 2-month period. Total E. coli was enumerated using the IDEXX Quanti-Tray/2000 system. DNA extracted from water samples was analyzed via quantitative real-time PCR (qPCR) for general and source-specific total Bacteroidales and human Bacteroidales markers, and digital PCR (dPCR) for antibiotic resistance genes (ARG) and a plasmid (pBI143) associated with human waste. SourceTracker2 was used to determine human source contributions based on metagenomic analysis of PCR-amplified 16S rRNA gene fragments. Samples collected immediately after the hurricane had elevated levels of E. coli, ranging from 488 to 1,733 CFU 100 ml−1. After 1 week, E. coli levels decreased to <100 MPN 100 ml−1. Total Bacteroidales numbers were elevated immediately following the hurricane and remained high for 12 days. Human-source contributions, as assessed by PCR methods and metagenomic analysis, peaked within 12 days after the hurricane consistently across all sampling sites. Multiple regression analysis of environmental parameters, copies of ARG and pBI143, and metagenomic data confirmed that human waste caused the dramatic, short-term, high levels of fecal contamination of floodwaters generated by Hurricane Harvey. Fecal indicators approached normal background levels approximately 3 weeks after the rainfall ended. [ABSTRACT FROM AUTHOR]

Pectinase accelerates hemp retting. An elevated temperature during the enzymatic action is favorable for bacterial colonization. Industrial hemp (Cannabis sativa L.) bast fiber was retted in a 40 °C water bath under four different conditions: water retting, pectinase retting, bacterial retting, and bacterial retting with the presence of pectinase. Bacterial communities were sampled from the retting liquid of each condition at the beginning of retting and on days 1, 3, and 5. The bacterial successions were identified by 16S rRNA gene metagenomic sequencing. The results showed that Bacillaceae dominated the hemp retting conditions containing 1% (m/v) pectinase, suggesting that pectinase can manipulate the bacterial community succession by changing the nutrients available to bacteria through the breakdown of pectin. Micromorphological analysis also observed the degradation of a gum-like substance and the aggregation of bacteria with the addition of pectinase. [ABSTRACT FROM AUTHOR]

Maternal separation with early weaning (MSEW) is a popular early life stress (ELS) model in rodents, which emulates childhood neglect through scheduled mother-offspring separation. Although variations of ELS models, including maternal separation and MSEW, have been published for the mouse species, the reported results are inconsistent. Corticosterone is considered the main stress hormone involved in regulating stress responses in rodents—yet generating a robust and reproducible corticosterone response in mouse models of ELS has been elusive. Considering the current lack of standardization for MSEW protocols, these inconsistent results may be attributed to variations in model methodologies. Here, we compared the effects of select early wean diet sources—which are the non-milk diets used to complete early weaning in MSEW pups—on the immediate stress phenotype of C57BL/6J mice at postnatal day 21. Non-aversive handling was an integral component of our modified MSEW model. The evaluation of body weight and serum corticosterone revealed the early wean diet to be a key variable in the resulting stress phenotype. Interestingly, select non-milk diets facilitated a stress phenotype in which low body weight was accompanied by significant corticosterone elevation. Our data indicate that dietary considerations are critical in MSEW-based studies and provide insight into improving the reproducibility of key stress-associated outcomes as a function of this widely used ELS paradigm. [ABSTRACT FROM AUTHOR]