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Autism can be described as a mental disorder that displays social interactions and communication impairments as well as a restricted range of activities or interests. Since autism is different for each individual, possible treatments are challenging and should consider individual characteristics at all times. Interactions with peers, family, and teachers are challenging for those with autism as they usually lack behaviors such as eye contact, playing, and talking with other people. It is common to observe sensorial issues as hypersensitivity in these individuals. Patients may have visual, auditive, or even tactile dysfunctions.
Dir/Floortime is a comprehensive model that gives theoretical support and methodological approach to lead to development focusing on the development of individual capacities for sensorial organization, motor planning, language, and many abilities that provide a development trail that will help individuals to achieve essential milestones to infants and adolescents. The DIR/Floortime is based on the development as a lifespan event, individual differences, and relationships established with peers and any other people in the child´s context.
The aim of this study was to demonstrate that the DIR/Floortime is a comprehensive method of study and intervention since it matches all necessary characteristics to produce development.
It was performed a theoretic approach of both DIR/Floortime and Biological Theory of Human Development in search of basis in a contextualist theory to explain a practical method of intervention.
Psychological theories about human development are important tools for understanding the way individuals interact with their context and produce changes in biopsychosocial characteristics. The Bioecological theory of Human Development is a contextualist theory that considers the interactions established between individuals through a model called PPCT, with their characteristics with people, objects, and symbols through interactions known as proximal processes, considered to be meaningful interactions, occurring frequently, through a long time.
The TBDH through the PPCT model can show that the DIR/Floortime presented itself as an efficient method for the treatment of autism since it considers the personal characteristics of the patients, especially their sensory and motor characteristics (Personal Characteristics such as Resource, Demand, and Force). This method has in significant interaction the most efficient way to produce development (equivalent to proximal Proximal Processes), takes into account the contexts where the developing individual attends, especially home, school and therapy, and has time as an essential factor for development to occur.
Adolescence can be seen as a fundamental stage of life for the construction of the subject, resulting from childhood experiences and decisive for adulthood. It is common stressors to appear during adolescence, due to the lack of necessary resources to deal with a stressful problem or event. In this way, the evaluation of a stressful situation by the adolescent is important, because from it he will develop coping strategies that will help him to deal with the problem.
Stressful life experiences, whether important events or even common annoyances, threaten the adolescent’s well-being, in addition to being linked to mental health and behavior problems, both internalizing ones, such as isolation, somatic complaints and anxiety/depression, as well as externalizing factors such as breaking rules and aggressive behavior. Romantic relationships are related to a major source of stress in the lives of these young people when conflicts, jealousy, aggression and infidelity occur, and have a great impact on the mental health of the individuals involved. Breakups, for example, have been linked to the onset of clinical depression in adolescents.
There are three categories of concern for adolescents: (a) related to achievements, such as success in school or opportunity for success in the future; (b) relationships with colleagues or family members; and (c) social problems such as the environment, poverty and unemployment.
To identify and describe stressful life events in adolescents from public schools in a poor community in Brazil.
The study included 64 adolescents, boys (51.56%) and girls (48.43%), aged between 12 and 16 years old (average 13.76%). The Adolescent Perceived Events Scale (APES) was used, which consists of 90 items that correspond to events that may occur in the adolescent’s daily life.
The most significant stressors for the adolescents in this study were those dealing with the death of close people, such as a friend (100%), a family member (96.29%) and a relative (94.73%). Also appearing as major stressors were “plans that did not work” (91.89%), use of alcohol or drugs by family members (87.5%), loss of a job by parents (75%), imprisonment of a family member (75%), fights with boyfriend or girlfriend (86.66%), breakup (75%) and concern about their own appearance (76.52%).
Events referring to interpersonal relationships were considered the greatest stressors, with percentages above 80%. The present study contributed to the understanding of adolescents’ perceptions of their life events. In this way, we can understand the relationship between stressors and the coping strategies. Furthermore, it allows the proposition of preventive intervention strategies in the school context.
Adolescence presents itself as a phase of life marked by rapid changes produced by different social contexts and in many cases, it can be configured in a stressful situation. The development of a psychosocial support network is of fundamental importance for adolescents to cope with the pressures of life in challenging situations. Many students, especially living in poor communities, face school problems especially because the curriculum fails to provide relevant knowledge to students in a way it can be meaningful and easier to be taught by teachers and learned by students. When students fail at school usually, they tend to blame themselves and as a result they may develop anxiety, social isolation and even depression.
Through the Bioecological Theory of Human Development, we sought to understand the psychosocial support networks of adolescents, whether or not experiencing school problems, considering this to be a challenging event.
In this research it was used the Five Fields Map, an instrument that evaluated the psychosocial support network for adolescents. The students with and without school problems filled the map in the beginning of the year and then at the end of the same year while facing a school problem as repeating the whole year because of insufficient grades.
The number of relationships between students facing and not facing school problems was not different, however, failing students had fewer relationships in the school-church Mesosystem, fewer relationships in the second and third levels in the first and second moments of data collection, and more relationships in level 5 in the second moment.
School problem Beginning
School Problem End
Both group of students showed great strength of proximity in their psychosocial support networks, indicating that it provided sufficient support so that the outcome of the failure experience was positive.
Children with Autism Spectrum Disorder (ASD) have a qualitative deficit in social interaction, engagement, and behavior. The DIR/Floortime model is one of the ways of intervention and is based on the child’s Functional Development, Individual differences, and Relationships. It aims to build the foundation for the social, emotional, and intellectual skills of children, instead of having the focus only on isolated behaviors. The model was developed by Stanley Greenspan and Serena Wieder in the United States and is the result of many years of observations and studies on child development since the 1950s. In the 1980s, they unified knowledge from several related studies on child development and mental health and recognized the importance of relationships and affection for learning. One of the considerations of the DIR/Floortime model on children with autism is the individual profile, that is, their individual differences (the I of the DIR). Each child has a unique way of perceiving the world (sight, sounds, touch) and responding to it. They may have difficulties in processing or responding to sensory information. Their individual differences need to be well known so that we can draw up a therapeutic plan to obtain the best developmental evolution.
Recognize and analyze the individual differences of each child, so that the appropriate therapeutic plan can be traced for the development of their potential.
Participated in the study 63 children with ASD, 12 girls (19%) and 51 boys (81%). Global Development Assessment questionnaires were used, based on the FEDC and the FEAS scale of the DIR/Floortime.
All 63 children presented sensory alterations such as proprioceptive, visual, and vestibular search or hyper-reactivity, directly impacting abilities such as visuospatial processing and motor planning. In addition, 85% of children have low body tone. Regarding the sensory need for visual search, presented by 86% of the children, as well as the vestibular (90%), a recommended therapeutic strategy is mapping the place, with fewer objects. The therapist needs to be in a fixed position and maintain a pleasant, lower tone of voice. The routine framework for motor and action planning, anticipating, and giving the necessary waiting time for the child to get organized. Motor circuits can also help to work with the tone, as well as with praxis.
The DIR/Floortime model aims to make the child develop the ability to interact meaningfully and connect with the outside world. The individual differences of the child need to be known so that this work can take place effectively and so that the therapist can better organize the therapy, providing the best development for the child.
An infectious disease such as COVID-19 can have a great impact on mental health due to the fear of contracting it as well as the social isolation itself due to the containment measures. Such events are considered stressors, as they can be perceived as threatening or challenging, and can have cumulative effects that are harmful to mental health. Along with this scenario, anxiety can occur in association with stress, and it is defined as extreme concern and somatic symptoms that generate tension, hindering the proper functioning and development of basic life functions. In people with Autism Spectrum Disorder (ASD) and their families, such events can occur more intensely, as changing routine and adapting to different activities are usually challenging. The study examined stress, anxiety and coping strategies during the pandemic.
To analyze stressful events, anxiety and coping strategies in caregivers of children and adolescents with ASD and typical development.
Forty caregivers of children and adolescents with ASD and 40 of typically developing participated in the study. The assessment instruments used were: 1. RSQ COVID-19; 2. Semi-structured interview; 3. State–Trait Anxiety Inventory for Adults. For statistical analysis, analysis of variance (ANOVA) or chi-square were used.
Caregivers of children and adolescents with ASD showed greater stress and anxiety, in addition to using less adaptive coping strategies.
There is a great need to welcome families of children and adolescents with ASD, helping to develop coping or coping strategies.
The parasite biodiversity of mouse opossums in Brazil remains incompletely explored. We describe a new species of Subulura (Ascaridida: Subuluroidea) from the large intestine of the white-bellied woolly mouse opossum, Marmosa constantiae, based on the results of light and scanning electron microscopy (SEM). We also partially sequenced the mitochondrial cytochrome c oxidase I (MT-CO1) gene of the new species, using molecular phylogenetic analyses to determine its relationships within the Subuluroidea superfamily. As molecular data on subuluroid species are extremely limited, few inferences could be drawn from our phylogenies. Our SEM observations showed the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, phasmids and vulva. Subulura eliseae sp. n. differs from the other four Subulura parasites species of marsupials by the number of caudal papillae and the structure dimensions, and size of the spicule. Moreover, S. eliseae sp. n. has ten pairs of caudal papillae, which is unique compared to other species. We present morphometric and molecular data on this new species, contributing to future studies on subuluroids.
Individuals with CLP may present communication disorders, velopharyngeal dysfunction, dento-occlusal changes and hearing losses. Adolescents with CLP usually show greater impairment of communication. Such characteristics combined with the malformed face can impact psychosocial functioning and increase the risk of psychological difficulties. Life-stressing experiences from CLP to life events typical of adolescence, may threaten the well-being of the adolescent, and are linked to mental health and behavioral problems.
To verify the coping of adolescents with CLP through a descriptive cross - sectional study.
Fifteen adolescents with CLP participated in the study. To evaluate them it was used the Coping scale (Lees, 2007), for the verification of coping in the families proposed by Motivational Theory of Coping. The analysis of the coping of adolescents with CLP considered two adverse contexts, namely “birth with fissure” and “have your secret told by a friend ”.
In relation to the evaluation of the psychological needs of relationship, competence and autonomy faced the “birth with fissure” indicates that teens with fissures do not perceive this stressor as a threat to their basic psychological needs.
The adolescents with CLP who participated in the study feel more interested (perception of the challenge) in dealing with the stressor relative to the fissure than in dealing with the betrayal of a friend, who reveals a secret of his to other people.
COVID-19 is a respiratory disease and its main symptoms are fever, dry cough and difficulty breathing. It spread to several countries, which led the World Health Organization to decree, on March 11, 2020, a pandemic state that deeply affected Brazil. Due to the impossibility of leaving the house, the routine of children with autism was changed. Children in Autism Spectrum Disorder (ASD) have a qualitative deficit in social interaction. Clinical and daily observations reinforce several scientific studies that defend the importance of maintaining a routine as stable as possible for people with ASD, without this stability they may become emotionally disorganized, feel discomfort or even irritability.
Investigate the impact caused by social distancing on the development of children and adolescents with autism.
An online questionnaire based on the DIR/Floortime basic map of emotional functional capacity development was distributed in Brazil from April to May, 2020. The results were analyzed using SPSS software.
Results obtained from 122 questionnaires showed that after 30 days of quarantine 20% of children no longer had the characteristic of being able to remain calm and organized for at least 2 minutes; 11% no longer initiates interactions with their parents; 27% demonstrated more protests and anger than before the social distancing; 18% demonstrated more emotions such as anger, fear and intimacy, 28% began to understand their limits and 12% of the children are using greater facial expression during the social distancing.
This study brings results that can help to understand the processes in a child with autism.
Children in Autism Spectrum Disorder (ASD) have a qualitative deficit in social interaction. The DIR/Floortime (Stanley Greenspan and Serena Wieder) is based on the Child’s Functional Development, Individual Differences and Relationships (D for development, I for individuality or individual differences and R for relationship), aiming at building the foundations for social, emotional and intellectual skills of children.
To determine the results of 18 months DIR/Floortime™ parent training for an additional benefit in encouraging children with ASD climbing the developmental “ladder”.
The participants are 15 children with ASD aged between 2 and 6 years-old. The follow-up occurs in two private DIR Floortime Model service centers in Brazil. Protocols: Functional Emotional Assessment Scale – FEAS and Functional Emotional Developmental Questionnaire – FEDQ. The participants were followed-up one on one every four months.
At the first month of assessment the children showed lack of self regulation, social interaction and engagement with their parents in a symbolic, sensory and motor play setting. At the following evaluations, they showed increase of social interaction and engagement in the same play setting. Besides the high affect of the parents during the play time promoted a two way purpose communication and behavioral organization.
Children showed a good development of functional and emotional capacities during the study period, demonstrating the effectiveness of the DIR/Floortime model in the intervention.
In the midst of a global pandemic with a rising death toll, the children´s mental health can be easily overlooked in the country’s response. But this overlook would have devastating consequences for years to come.
The objective of this research is to compare children’s physical and mental development before, during and after the situation of social isolation caused by the pandemic of COVID-19.
The parents/guardians of 100 children aged between 0 and 5 years and 11 months old were asked to answer questions based on the ASQ-3 (Ages and Stages Questionnaire III), containing questions related to Communication, Gross Motor, Fine Motor, Problem Solving, and Personal-Social and ASQ- SE (Ages and Stages Questionnaires Social-Emotional) addressing issues of self-regulation, compliance, social-communication, adaptive functioning, autonomy, and affect. In addition, behavioral issues related to children’s mental health will be included, such as: aggressiveness, insomnia, lack of appetite, apathy, sadness, tiredness, lack of interest, hyperactivity, manias, tantrum, morning among others. Child development data will be collected before and during quarantine / isolation and later, in a second stage, after the end of social isolation.
The data will be analyzed in order to characterize child behavior before, during and after the period of social isolation, correlating the different areas of child development, especially mental health.
As argued, socially isolated children are at increased risk of health problems in adulthood. Furthermore, studies on social isolation have demonstrated that a lack of social relationships negatively impacts the development of the brain’s structure.
When parents discover that their child has hearing loss, a new reality presents itself with frustration, a huge amount of work as special care, therapies, exams, etc. Adapting to this new situation is a huge challenge to the development of both parents and children who receive this diagnosis.
This study investigated how Brazilian parents of children diagnosed with hearing loss dealt with this situation from diagnosis to the present day.
In this study it was used the Bioecological Theory of Human Development, which considers the development of both parents and children over time. Two meetings were conducted using a focal group technique, with questions related to the diagnosis and how they faced the situation, prejudice, care of other siblings, etc.
Most parents discovered the diagnosis of hearing loss of their children right after birth. Only one mother said she did not care about the diagnosis of hearing loss while most reported having suffered a lot and glimpsed a life of difficulties. Even knowing the limitations imposed by the condition of the children, no one considered hearing loss as a sickness. Parents reported that the child suffered bullying because of difficulties in speaking and most parents say they worry about their children’s school life.
Parenting kids with hearing impairment is challenging, and involves dealing with prejudice, fear of future, long-term therapies and high costs. Nevertheless parents make great efforts to provide a good environment minimizing the risks of having such condition.
An experiment was conducted to evaluate: (1) the effects of ensiling maize or sorghum grains after reconstitution on readily soluble fraction (a), potentially degradable fraction in the rumen (b) and rate constant for degradation of b (c) of dry matter (DM), organic matter (OM) and starch (STA); and (2) an appropriate incubation time for in situ or in vitro procedures to estimate in vivo digestibility. Four rumen-cannulated Nellore bulls (body weight = 262 ± 19.6 kg) distributed in a 4 × 4 Latin square were used. Diets were based on dry ground maize (DGM); or dry ground sorghum (DGS); or reconstituted ground maize silage; or reconstituted ground sorghum silage. In vitro and in situ incubations of the individual grains and diets were simultaneously performed with in vivo digestibility. In general, reconstituted grains and diets based on reconstituted grains presented greater (P < 0.05) fraction a and lower (P < 0.05) fraction b of DM, OM and STA compared to dry grains and diets based on dry grain. However, the magnitude of response of the reconstitution and ensiling process on DM and OM degradability parameter was greater for maize than that for sorghum. Moreover, no differences (P > 0.05) were observed between DGM- and DGS-based diets for c estimates. The results suggest that the reconstitution process promotes grains protein matrix breakdown increasing STA availability. The incubation times required for in vivo digestibility estimations of DM, OM and STA are 24 h for in situ and 36 h for in vitro procedures.
There are some data that suggest the existence of a dysfunction of the Hypothalamic-Pituitary-Adrenal (HPA) Axis in patients with eating disorders (anorexia nervosa –AN- and bulimia nervosa -BN-). If such a dysfunction exists, it would result in an altered cortisol response to stress.
To compare the cortisol response to stress in a group of patients with AN, BN and a control group.
Seventeen female AN patients, 17 female BN patients and 26 healthy female controls were compared. The Trier Social Stress Test (TSST) was used to induce stress. Throughout the test, seven samples of saliva were collected from each subject, and cortisol was investigated in each of the samples using radioimmunoassay (RIA).
Each group had a specific profile of cortisol release. Upon arrival at the laboratory, the AN patients had higher cortisol levels, but they quickly returned to normal values, becoming similar to those of controls. In contrast, in the BN patients the cortisol levels were at any time significantly lower than those of the AN patients and the controls, displaying a globally blunted response.
The results support the hypothesis of a dysfunctional functioning of HPA axis in patients with eatings disorders, althoug suggest that it might be particularly important in BN patients.
Supported by grants PI060974 (Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica [I+D+I]. FIS. Instituto Salud Carlos III. Ministerio de Sanidad, Servicios Sociales e Igualdad) and GRU09173 (Plan de Investigación Regional de Extremadura. Gobierno de Extremadura y European Social Fund).
Forage brassicas, such as summer turnip (ST; Brassica rapa) and forage rape (FR; Brassica napus), are used as supplementary crops during summer. However, studies with lactating dairy cows fed these forages are limited and report inconsistent productive responses. The aim of this study was to determine dry matter intake, rumen fermentation and milk production responses of dairy cows in mid-lactation supplemented with and without summer (‘ST’ or ‘FR’) brassicas. Twelve multiparous lactating dairy cows were randomly allocated to three dietary treatments in a replicated 3 × 3 Latin square design balanced for residual effects over three 21-day periods. The control diet consisted of 16.2 kg DM of grass silage, 2.25 kg DM of commercial concentrate and 2.25 kg DM solvent-extracted soybean meal. For the other two dietary treatments, 25% of the amounts of silage and concentrates were replaced with FR or ST. The inclusion of forage brassicas had no effects on milk production (24.2 kg cow/day average) and composition (average milk fat and protein 43.2 and 33.6 g/l, respectively). Dry matter intake was 0.98 kg and 1.12 kg lower for cows supplemented with FR and ST, respectively, resulting in a greater feed conversion efficiency (1.35 kg milk/kg DM for ST and FR v. 1.27 kg milk/kg DM for the control diet). Intraruminal pH was lower for cows supplemented with ST compared to the control diet; however, it did not decrease below pH 5.8 at any time of the day. After feeding, the concentrations of total short-chain fatty acids (SCFAs) in rumen contents increased with ST supplementation compared to the control diet. Inclusion of FR in the diet increased the molar proportion of acetate (68.5 mmol/100 mmol) in total SCFA at the expense of propionate, measured 6 h after feeding of the forage. The molar proportion of butyric acid was greater with ST and FR supplementation (13.1 and 12 mmol/100 mmol, respectively) than in control cows. The estimated microbial nitrogen (N) flow was 89.1 g/day greater when supplementing FR compared to the control diet. Based on the haematological measures, the inclusion of summer brassica forages did not affect the health status of the animals. These results indicate that mid-lactation dairy cows fed brassicas are able to maintain production despite the reduced intake, probably due to improved rumen fermentation and therefore nutrient utilization.
This work reports the synthesis and characterization of metal-free electrocatalysts made from Brosimum alicastrum waste as the carbon source. The residues were washed and grounded to a fine powder. The thermogravimetric analysis carried out on the raw sample showed that the optimal synthesis temperature is 700 °C. Thus, the raw sample was pyrolyzed at 700 °C and activated with potassium hydroxide (KOH) in a 2:1 ratio (KOH/fine power) to improve its properties. Afterwards, hydrazine was used as the nitrogen source for doping. The physicochemical characteristics of pyrolyzed, activated, and doped carbons were studied and their electrochemical properties were determined using cyclic and linear voltammetry techniques. The electrochemical measurements indicate that the sample doped at 140 °C has an acceptable onset potential (0.854 V vs. RHE), while the one doped at 160 °C shows the highest current density among the synthesized electrocatalysts (2.61 mA cm-2). Although the catalyst performance is lower compared to commercial 20% Pt/C, this biomass precursor favors the oxygen reduction reaction in alkaline media.
Low methane (CH4) emissions from sheep fed forage rape (Brassica napus) might be related to low ruminal pH value. In this study, sodium carbonate (Na2CO3: SC) was supplemented to the diet to alter ruminal pH for evaluation of its role in CH4 emissions from sheep fed forage rape. Fourteen intact and eight fistulated Romney sheep were adapted to forage rape over 32 days and then randomly allocated to one of two groups: diets supplemented with SC or not (control). Methane emissions were measured from intact sheep in seven experimental periods. In parallel, ruminal pH and fermentation characteristics were assessed using the fistulated sheep. In the first (P01) and the second (P02) periods, none of the sheep received SC to examine the baseline CH4 emissions. The P01 period was used as a covariate for analysis of gas emission measurements in subsequent measurement periods. Sodium carbonate was offered at 5% of the forage DM in P03 and P04, increased to 8% in P05 and P06 to assess the effect of pH increase on CH4 emissions and stopped in P07 to assess if the CH4 emissions reverted to values similar to those measured before the supplementation started. Methane yield (g/kg forage DM intake) was similar for the sheep in both groups during P02 and P03, but sheep supplemented with SC in the diet emitted 36%, 49% and 30% more CH4 per unit of forage DM intake than those in the control group during P04, P05 and P06, respectively. Emissions returned to similar levels when SC supplementation was ceased in P07. Ruminal pH was 0.412 to 0.565 units higher in SC supplemented sheep than for the control group during the SC treatment periods. Based on the lack of an immediate response in CH4 emissions to the supplementation of SC in P03, the positive responses in P04 to P06 and the rapid disappearance of the response after supplementation with SC stopped in P07, we propose a new hypothesis that ruminal pH effects on CH4 emissions are possibly through medium-term changes in microbial and methanogenic communities in the rumen, rather than a direct, short-term impact on methanogens per se. In conclusion, SC supplemented to the forage rape diet of sheep increased rumen pH, leading to an increase in CH4 emissions. Low ruminal pH in sheep fed forage rape explains, at least partially, the reported low CH4 emissions from sheep fed with this forage crop.
The disease caused by the influenza virus is a global public health problem due to its high rates of morbidity and mortality. Thus, analysis of the information generated by epidemiological surveillance systems has vital importance for health decision making. A retrospective analysis was performed using data generated by the four molecular diagnostic laboratories of the Mexican Social Security Institute between 2010 and 2016. Demographics, influenza positivity, seasonality, treatment choices and vaccination status analyses were performed for the vaccine according to its composition for each season. In all cases, both the different influenza subtypes and different age groups were considered separately. The circulation of A/H1N1pdm09 (48.7%), influenza A/H3N2 (21.1%), influenza B (12.6%), influenza A not subtyped (11%) and influenza A/H1N1 (6.6%) exhibited well-defined annual seasonality between November and March, and there were significant increases in the number of cases every 2 years. An inadequate use of oseltamivir was determined in 38% of cases, and the vaccination status in general varied between 12.1 and 18.5% depending on the season. Our results provide current information about influenza in Mexico and demonstrate the need to update both operational case definitions and medical practice guidelines to reduce the inappropriate use of antibiotics and antivirals.
Eight ruminally-fistulated wethers were used to examine the temporal effects of afternoon (PM; 1600h) v. morning (AM; 0800 h) allocation of fresh spring herbage from a perennial ryegrass (Lolium perenne L.)-based pasture on fermentation and microbial community dynamics. Herbage chemical composition was minimally affected by time of allocation, but daily mean ammonia concentrations were greater for the PM group. The 24-h pattern of ruminal fermentation (i.e. time of sampling relative to time of allocation), however, varied considerably for all fermentation variables (P⩽0.001). Most notably amongst ruminal fermentation characteristics, ammonia concentrations showed a substantial temporal variation; concentrations of ammonia were 1.7-, 2.0- and 2.2-fold greater in rumens of PM wethers at 4, 6 and 8h after allocation, respectively, compared with AM wethers. The relative abundances of archaeal and ciliate protozoal taxa were similar across allocation groups. In contrast, the relative abundances of members of the rumen bacterial community, like Prevotella 1 (P=0.04), Bacteroidales RF16 group (P=0.005) and Fibrobacter spp. (P=0.008) were greater for the AM group, whereas the relative abundance of Kandleria spp. was greater (P=0.04) for the PM group. Of these taxa, only Prevotella 1 (P=0.04) and Kandleria (P<0.001) showed a significant interaction between time of allocation and time of sampling relative to feed allocation. Relative abundances of Prevotella 1 were greater at 2h (P=0.05), 4h (P=0.003) and 6h (P=0.01) after AM allocation of new herbage, whereas relative abundances of Kandleria were greater at 2h (P=0.003) and 4h (P<0.001) after PM allocation. The early post-allocation rise in ammonia concentrations in PM rumens occurred simultaneously with sharp increases in the relative abundance of Kandleria spp. and with a decline in the relative abundance of Prevotella. All measures of fermentation and most microbial community composition data showed highly dynamic changes in concentrations and genus abundances, respectively, with substantial temporal changes occurring within the first 8h of allocating a new strip of herbage. The dynamic changes in the relative abundances of certain bacterial groups, in synchrony with a substantial diurnal variation in ammonia concentrations, has potential effects on the efficiency by which N is utilised by the grazing ruminant.
As vitamin B12 is only synthesized by bacteria, ruminant products, especially dairy products, are excellent sources of this vitamin. This study aims to identify if diet and cow characteristics could affect vitamin B12 concentration in milk of dairy cows. Information on 1484 first, 1093 second and 1763 third and greater parity Holstein cows in 100 herds was collected during three consecutive milkings. During the first morning milking, all dietary ingredients given to cows were sampled and quantities offered were recorded throughout the day. Nutrient composition of ingredients was obtained by wet chemistry to reconstitute nutrient composition of the ration. Milk samples were taken with in-line milk meters during the evening milking of the 1st day and the morning milking of the 2nd day and were analyzed for vitamin B12 concentration. Milk yields were recorded and milk components were separately analyzed for each milking. Daily vitamin B12 concentration in milk was obtained using morning and evening vitamin B12 concentrations weighted with respective milk yield, then divided by daily yield. To decrease the number of interdependent variables to include in the multivariable model, a principal component analysis was carried out. Daily milk concentration of vitamin B12 averaged 3809±80 pg/ml, 4178±79 pg/ml and 4399±77 pg/ml for first, second and third, and greater lactation cows. Out of 11 principal components, six were significantly related to daily milk concentration of vitamin B12 when entered in the multivariable model. Results suggested that vitamin B12 concentration in milk was positively related to percentage of fiber and negatively related to starch as well as energy of the diet. Negative relationships were noted between vitamin B12 concentration in milk and milk yield as well as milk lactose concentration and positive relationships were observed between vitamin B12 concentration in milk and milk fat as well as protein concentrations. The percentages of chopped mixed silage and commercial energy supplement in the diet as well as cow BW were positively related to vitamin B12 in milk and percentages of baled mixed silage, corn and commercial protein supplement in the ration were negatively related to vitamin B12 concentration in milk. The pseudo-R2 of the model was low (52%) suggesting that diet and cow characteristics have moderate impact on vitamin B12 concentration in milk. Moreover, when entering solely the principal component related to milk production in the model, the pseudo-R2 was 46%. In conclusion, it suggests that studied diet characteristics have a marginal impact on vitamin B12 concentration in milk variation.
On-farm nutrition and management interventions to reduce enteric CH4 (eCH4) emission, the most abundant greenhouse gas from cattle, may also affect volatile solids and N excretion. The objective was to jointly quantify eCH4 emissions, digestible volatile solids (dVS) excretion and N excretion from dairy cattle, based on dietary variables and animal characteristics, and to evaluate relationships between these emissions and excreta. Univariate and Bayesian multivariate mixed-effects models fitted to 520 individual North American dairy cow records indicated dry matter (DM) intake and dietary ADF and CP to be the main predictors for production of eCH4 emissions and dVS and N excreta (g/day). Yields (g/kg DM intake) of eCH4 emissions and dVS and N excreta were best predicted by dietary ADF, dietary CP, milk yield and milk fat content. Intensities (g/kg fat- and protein-corrected milk) of eCH4, dVS and N excreta were best predicted by dietary ADF, dietary CP, days in milk and BW. A K-fold cross-validation indicated that eCH4 and urinary N variables had larger root mean square prediction error (RMSPE; % of observed mean) than dVS, fecal N and total N production (on average 24.3% and 26.5% v. 16.7%, 15.5% and 16.2%, respectively), whereas intensity variables had larger RMSPE than production and yields (29.4%, 14.7% and 14.6%, respectively). Univariate and multivariate equations performed relatively similar (18.8% v. 19.3% RMSPE). Mutual correlations indicated a trade-off for eCH4v. dVS yield. The multivariate model indicated a trade-off between eCH4 and dVS v. total N production, yield and intensity induced by dietary CP content.