Duration Of Dry Period Research Articles

Effectiveness of Intramammary Antibiotics, Internal Teat Sealants, or Both at Dry-Off in Dairy Cows: Milk Production and Somatic Cell Count Outcomes.

Simple SummaryA block randomized trial was conducted in California dairies to evaluate the effect of different treatments at dry-off on the subsequent lactation’s milk production and somatic cell count (SCC). Greater milk production was observed in cows treated with antibiotics and teat sealants at dry-off in comparison to controls, while there was no significant difference in the milk produced by cows that received either antibiotic or teat sealant in comparison to the untreated cows. Different dry cow treatments were associated with a reduction in ln SCC during the first 150 DIM, with the greatest reduction associated with both antibiotic and teat sealant in comparison to controls. Dairies with high SCC may benefit from treating cows at dry-off with AB, TS, or both.Mastitis is the greatest disease challenge for dairy producers, with substantial economic impacts due to lost milk production. Amongst the approaches implemented to control and prevent mastitis on dairies are vaccination, pre- and post-milking teat dips, and treatments at dry-off including intramammary antibiotics and teat sealants. The objectives of our study were to evaluate the effect of different treatments at dry-off on the subsequent lactation’s milk production and somatic cell count (SCC). A single-blinded controlled block randomized clinical trial was conducted between December 2016 and August 2018 on eight herds from four of the top ten milk-producing counties in California: Tulare, Kings, Stanislaus, and San Joaquin. The trial was repeated with cows enrolled during the winter and summer seasons to account for seasonal variability. Eligible cows were treated at dry-off with either intramammary antibiotics (AB), internal teat sealant (TS), AB + TS, or did not receive any treatment (control), and were followed through 150 days in milk (DIM) post-calving. The milk production and SCC data were extracted from monthly test day milk records (Dairy Comp 305, Valley Ag Software, Tulare, CA, USA). Two-piece spline linear mixed models were used to model the milk production (kg) and natural logarithm-transformed SCC. After accounting for parity, breed, season, and dry period duration, the milk model showed a significant increase in milk production (1.84 kg/day) in cows treated with AB + TS at dry-off in comparison to controls. There was no significant difference in the milk produced by cows that received either AB or TS (0.12 kg/day, and 0.67 kg/day, respectively) in comparison to the untreated cows. Different dry cow treatments were associated with a significant reduction in ln SCC during the first 150 DIM. The greatest reduction was associated with using AB + TS, followed by AB, and finally TS in comparison to controls. Dairies with high SCC may benefit from treating cows at dry-off with AB, TS, or both.

How does weather impact on beehive productivity in a Mediterranean island?

Bee productivity is an essential factor affecting, not only the production of honey or other beehive products but also food security due to the very important role of bees as pollinators. The behavior of the bees and thus their productivity is highly affected by the weather fluctuations. In the present study, five years (2015-2019) of beehive weight data were analyzedto assess the impact of the prevailing weather conditions at an east Mediterranean island, on the productivity of bees. The results indicate that temperature and water-related parameters, significantly affect beehive productivity. Specifically, temperature optimum values of 17oC in spring and 26oC in summer, are associated with higher daily relative changes of the beehive weight, while bee productivity enhances at daily temperatures between 14 and 28oC, presenting negative values beyond this range. The effects of temperature, windspeed, diurnal temperature range, vapor pressure deficit, saturation vapor pressure, and the duration of hot and dry periods, on beehive productivity are strong and negative, whereas the effect of relative humidity is also significant but positive. The results of the study enhance the knowledge of the weather impacts on beehive production especially under the climatic conditions of a small east Mediterranean island, with applications in beekeepers scheduling and hive designing, to maximize beehive productivity.

Effect of different dry period duration on milk components and serum metabolites, and their associations with the first conception rate in multiparous Holstein dairy cows

The aims of the present study were to evaluate the effects of different dry period (DP) lengths on milk fat to protein ratio (FPR) and metabolic status – blood leptin, adiponectin and non-esterified fatty acids (NEFA) concentrations in dairy cows, and their associations with the result of the first timed artificial insemination (TAI). Cows were blocked either to short DP (SDP; 30±2 days; n=72) or conventional DP (CDP; 60±2 days; n=76). Milk FPR was calculated at 30 and 60 days in milk (DIM). Body condition score (BCS) was recorded at –60, –30, calving, and 60 DIM. Blood samples were obtained at –60, –30, –7, calving, +7, +30, and +60 DIM for serum metabolites measurement. TAI was implemented between 65–75 DIM for all cows. Milk FPR and its changes were statistically analysed using an independent sample t test. To assess the impact of time, the pattern of BCS, and serum metabolites on the result of the first AI, repeated measure ANOVA was used. Only FPR-30 DIM revealed significant difference between pregnant and non-pregnant cows in SDP group (P<0.01). Reduced BCS loss was observed in the SDP group and followed by slightly higher probability of pregnancy at first AI (P=0.19). Leptin was not altered by shortening the DP (P≥0.1). Significant differences were observed in blood adiponectin prepartum (P<0.001) and at +7 DIM (P<0.01), as well as in NEFA at +7 and +30 DIM between the two groups (P<0.05). Pregnant cows following the first AI had significantly high postpartum leptin concentrations (P<0.05), high prepartum adiponectin (P≤0.001), and lower NEFA at +7 DIM (P<0.01) in the SDP group. In conclusion, shortening the dry period caused reduced BCS loss postpartum and variations in serum metabolits that favoured the possibility of pregnancy at first AI.

REPRODUCTIVE ABILITY OF FIRST-CALF COWS OF SIMMENTAL BREED IN ORGANIC AND CONVENTIONAL MILK PRODUCTION

The aim of the work was to study the influence of biological periods of reproduction of first-born cows of Simmental breed on their productive features of organic and conventional milk production.
 Research materials and methods. The research was carried out in the herds of Simmental breed PС "Halex-Agro" (organic milk production, n = 272) and LLC "Myroslavel-Agro" (conventional milk production, n = 120) Novograd-Volyn district of Zhytomyr region according to conventional methods.
 Research results. The article presents the results of research on the influence of the age of the first fertile insemination, age of first calving, the duration of service and dry periods of Simmental cows in their productive traits in organic and conventional milk production.
 The best indicators, regardless of the technology of milk production, were characterized by animals of the middle group, the age of the first fertile insemination of these animals in PE "Galex-Agro" ranged from 526 to 678 days, and in STOV "Miroslavel-Agro" – from 505 to 648 days. The value of this indicator within farms was 462.5 and 458.0 kg, respectively. Therefore, both early insemination and late insemination were not desirable for this herd, because with early insemination farmers don’t get enough milk and there is a high probability of giving birth to calves with lower live weight, while with late insemination there is an irrational overuse of investments in uncovered heifers. their future milk productivity.
 In the conditions of both farms there is a clear pattern that animals with an earlier age of the first fertile insemination are characterized by more intensive formation of live weight. Animals of the first and second experimental groups were statistically significantly superior to peers of the third experimental group in live weight at the age of 3 to 18 months in PE "Galex-Agro", and from 6 to 18 months in STOV "Myroslavel-Agro" (P < 0.05–0.01). There is almost the same live weight of heifers at different ages in both farms, due to the common origin of the breeding stock imported from the Czech Republic.
 It has been established that with increasing age of the first calving milk productivity of cows increases. The highest yield for 305 days (6117.2 and 5937.6 kg) and all lactation (6920.9 and 6953.4 kg) were observed in cows whose age of first calving was 995 and older and 917 and older days in the conditions of PE "Galeks-Agro” and STOV “Myroslavel-Agro” respectively. The lowest yield for 305 days (5733.9 and 5863.0 kg) and all lactation (6528.2 and 6424.6 kg) were in cows with the age of the first calving 835 and less and 778 and less days in both farms, respectively.
 There was a statistically significant effect (P < 0.01–0.001) of the duration of the service period in both farms on the duration of lactation of cows (58.6 and 63.9%), hopes (22.8 and 34.2%), as well as on the fat content in milk (2.2%) only in the conditions of PE "Galex-Agro". In the conditions of intensive management of the dairy industry in organic and conventional production, it is necessary to take into account the rate of reproduction of the herd, which is largely determined by the length of the service period. The service period is one of the key indicators that determines not only the reproduction of animals, but also their future milk productivity.
 Conclusions. According to the results of our own research, it was found that the extension of the service period leads to an increase in the duration of biological periods of reproduction and to a decrease in the coefficient of reproducibility (from 1.06 to 0.68; from 1.05 to 0.72), which is predictable. Statistically significant effect (P < 0.001) of the value of the service period was found in the conditions of PE "Galex-Agro" and LLC "Miroslavel-Agro" on the duration of the interbody period (74.2 and 68.8%), the coefficient of reproducibility and 78.2), as well as the duration of the dry period (2.6%) and the age of the first calving (2.7%) only in the conditions of PE "Galex-Agro".
 When comparing animals with a shortened and optimal duration of the dry period, a statistically significant difference was found in the conditions of organic production in the duration of lactation (25.3 days), milk yield during lactation (673 kg) and 305 days (359 kg), milk fat (13.7), milk protein (13.4 kg), total milk fat and protein production (26.2 kg). In terms of conventional production, animals with a shorter dry period are characterized by longer lactation and higher milk yield.

Effects of drip irrigation nitrogen coupling on dry matter accumulation and yield of Summer Maize in arid areas of China

To explore the effects of irrigation and nitrogen on dry matter accumulation (DMA) and yield of summer maize in arid regions, field experiments were conducted in experimental plot in 2017 and 2018. There were three drip irrigation quotas (3000 m3/hm2, 3750 m3/hm2, and 4500 m3/hm2) and four nitrogen levels (no nitrogen applied, 168 kg/hm2, 306.5 kg/hm2, and 444.5 kg/hm2) set in the experiment. The Richards model was used to fit the relationship of DMA and irrigation quantity or nitrogen level, and then the dynamics of DMA of maize were investigated. Furthermore, the effects of irrigation and nitrogen on maize grain yield were analyzed. Results showed that the maximum and average DMA rates in maize plants increased as irrigation quota increased from 3000 to 3750 m3/hm2 and as the applied nitrogen increased from 0 to 306.5 kg/hm2. Maize plants under the condition of irrigation 3750 m3/hm2 together with nitrogen 306.5 kg/hm2 showed the maximum dry matter growth rate (GRmax), the maximum average dry matter growth rate (GRavg), the maximum duration of dry matter fast growth period, and the maximum DMA and grain yield. The maximum grain yield was up to 1.340 × 104 kg/hm2 and 1.291 × 104 kg/hm2 in 2017 and 2018, respectively. However, when the irrigation quota was increased to 4500 m3/hm2 and the nitrogen application rate was up to 444.5 kg/ hm2, GRmax, GRavg, and yield of maize were all decreased with the increase of irrigation quantity, this law is reproducible between years. So the management practice of irrigation 3750 m3/hm2 along with nitrogen 306.5 kg/hm2 is optimal for maize production in the experimental region. Furthermore, a stepwise regression model was established to predict grain yield (Y1) on the basis of the characteristic parameters of the Richards model, and the regression model was: Y1 = 0.499YGRmax+0.074GRavg-6.399x2+2.25, R2 = 0.803. The contribution rate of each characteristic parameter to yield prediction model from high to low was: YGRmax>GRavg>x2. GRavg was extremely positive correlated with the final DMA and yield of maize, the study would provide technical basis for the efficient utilization of water and nitrogen in arid regions.

ЗАГАЛЬНОСВІТОВІ ТЕНДЕНЦІЇ РОЗВИТКУ ГАЛУЗІ КОЗІВНИЦТВА ТА ОСНОВНІ ФАКТОРИ ФОРМУВАННЯ ЯКОСТІ КОЗЯЧОГО МОЛОКА

The aim of our study was to research of the current state of goat milk production in Ukraine and the world and outlined the main factors, including genetic, that determine its quality and, accordingly, the quality of cheese. It has been established that the general global trends in the development of goat breeding indicate the growing role of this field in the nutrition of the population. Thus, according to the Food and Agriculture Organization of the United Nations (FAO), there is a steady increase in both the number and gross goat milk production. According to the research conducted from 2015 to 2019, the number of dairy goats in the world increased by 6.8 % – to more than 215 million heads. The stable growth of them took place in Europe (+ 30.0 %) and Africa (+ 10.3%). The largest number of dairy goats was kept in 2019 in Asia (50.8 %) and Africa (40.0 %). Gross production of goat milk in the world by 4.9 % from 2015 to 2019 increased. In Ukraine, the situation in dairy goat breeding is still significantly different from global trends – during the period under study, the number of goats decreased by 6.8 %, gross milk production decreased by 14.5 %. The analytical material has been presented as to the dependence of the chemical composition of goat milk on genotypic and paratypic factors, such as: breed, age, yean season, lactation stages, duration of dry period and pregnancy, feeding, housing conditions, influence of the environment (temperature, humidity), body weight and etc. It has been noted that European breeds of dairy goats tend to have much greater potential for milk production than the local breeds that have not undergone selection changes. At the same time, many indigenous breeds of goats have higher dry matter content in milk and are better adapted to local housing and feeding conditions, especially under climate change. The global demand on goat milk products is predicted to increase as consumers become more demanding as to the quality of animal products, which are important in the daily diet owing to the optimal content of macro- and micronutrients.

ВЛИЯНИЕ ВОСПРОИЗВОДИТЕЛЬНЫХ КАЧЕСТВ НА МОЛОЧНУЮ ПРОДУКТИВНОСТЬ КОРОВ СИММЕНТАЛЬСКОЙ ПОРОДЫ

The applicability of the work is to identify the possibility of productivity increase of cows of the Simmental breed due to reproductive qualities. The aim of the work is to assess the influence of the first insemination age, service period and dry period on milk productivity of Simmental cows. The research is aimed at studying milk productivity of Simmental cows with different levels of reproductive qualities. The obtained data were statistically processed in Excel. Descriptive statistics methods were used. The object of the research were Simmental cows of “ Tasaliev D.M. “ farm of Kaliningrad region. As a result of the study, a relation was established between the age of the first successful insemination, the service period duration, the dry period duration and parameters of milk productivity. The age of the first successful insemination at 18-24 months has the most beneficial effect on subsequent milk productivity. A service period of 90-120 days has a positive effect on milk yield increase for 305 days of lactation, a longer service period negatively affects the mass fraction of milk fat. Prolonged service period results in a calf loss of 100 calves per year. With an increase of dry period duration, the mass fraction of milk fat increases, but milk yield decreases. The influence of reproductive qualities on mass fraction of milk protein is insignificant. According to the results of the studies, it can be considered that reproductive qualities, in combination with other factors, influence milk productivity of Simmental cows.

Spatio-temporal rainfall variability over different meteorological subdivisions in India: analysis using different machine learning techniques

Understanding and quantifying long-term rainfall variability at regional scale is important for a country like India where economic growth is very much dependent on agricultural production which in turn is closely linked to rainfall distribution. Using machine learning techniques viz., cluster analysis (CA) and principal component analysis (PCA), the spatial and temporal rainfall patterns over the meteorological subdivisions in India are examined. Monthly rainfall data of 117 years (1901–2017) from India Meteorological Department over 36 meteorological subdivisions in India is used in this study. Using hierarchical clustering method, six homogeneous rainfall clusters were identified in India. Among the rainfall clusters, Group 1 had 30% dissimilarity with Groups 2, 3, and 4 while Group 5 and Group 6 are highly dissimilar (more than 90% dissimilarity) with the rest of the groups. Rainfall seasons in each group were further classified into dry, wet, and transition periods. The duration of dry period is smaller in group which consists of subdivisions from southern part of the country. The transition period between dry and wet period was found to be smaller for subdivisions in the coastal region. Both CA and PCA showed high rainfall variability in Groups 5 and 6, which comprise subdivisions from north east, Kerala, Konkan, and costal Karnataka and low rainfall variability in Groups 1 and 2 which comprise subdivisions from east, north, and central part of the country. Strong negative trend in annual and Indian summer monsoon rainfall is seen in northeast India and Kerala while positive trend is observed over costal Karnataka and Konkan region. The negative trend in post monsoon rainfall particularly over the peninsular and northeast India indicates weakening of northeast monsoon rainfall in the country.

Effect of Dry Period Duration on Udder Health, Milk Production and Body Condition of Jersey Crossbred Cows at Lower Gangetic Tropics

Effect of Dry Period Duration on Udder Health, Milk Production and Body Condition of Jersey Crossbred Cows at Lower Gangetic Tropics

Evaluation of Prognostic Factors and Middle Ear Risk Index in Type 1 Tympanoplasty

Background: Chronic suppurative otitis media (CSOM) is a long-standing infection of middle ear cleft, characterized by ear discharge and permanent perforation of tympanic membrane. Surgical treatment of CSOM is still controversial. Recently many studies have been undertaken to evaluate the prognostic impact of various factors on the outcomes of tympanoplasty. Nonetheless, only few studies have assessed the clinical preoperative assessment method that allows for tympanoplasty outcome to be predicted. Objective: To examine the role of the prognostic factors and middle ear risk index on the success of tympanoplasty. Patients and methods: The medical records of 100 patients who underwent type 1 tympanoplasty between 2018 and 2020 were prospectively reviewed. Prognostic factors such as age, sex, presence of systemic diseases, location and size of perforation, duration of dry period, presence of myringosclerosis, presence of septal and conchal pathology, operation type, and status of the opposite ear were evaluated. Middle ear risk index (MERI) was calculated and its correlation with the rate of success of surgery was evaluated. Results: It was noticed that experience of surgeon more than 5 years, absence of comorbidities and low middle ear risk score were significant predictors for success of tympanoplasty type 1 (P < 0.001, P < 0.001, P < 0.001 respectively). Conclusion: We found that younger age, female gender, no comorbidities, and higher surgeon experience were associated with better outcome. In addition, patients with mild MERI score showed higher rate of success for tympanoplasty. The surgeon experience and MERI were independent predictors of successful procedure.

Characteristics of spring consecutive dry days with different durations across China based on the objective zoning approach

AbstractThe duration of dry periods is closely related to drought conditions and is used to evaluate the degree of drought. In this article, using the rotated empirical orthogonal function (REOF) and K‐medoids clustering methods and considering the spatial continuity, 500 stations in China are divided into 10 clusters to analyze the variation characteristics of consecutive dry days (CDDs) with different durations in spring. In Clusters 1–5 over the middle and lower reaches of the Yangtze River, South China, North China, and eastern and western Southwest China, the contribution percentage of short‐duration CDDs to total dry days decreases, while that of medium‐ and/or long‐duration CDDs increases, which leads to an increase in the total dry days and the duration of CDDs. In Clusters 6–8, the total dry days decrease, which are mainly contributed by the decreases in medium‐duration CDDs (for Cluster 6 over southern Northeast China) or long‐duration CDDs (for Clusters 7–8 over northern Northeast China and southern Xinjiang). The total dry days change little in Clusters 9–10 over eastern Northwest China and northern Xinjiang, which is attributed to the offset among the changes in the three‐type duration CDDs. In Clusters 6–10, the duration of CDDs shortens overall. The decadal changes of spring dry days in China exhibit remarkable regional differences. The total day days and three‐type duration CDDs in some clusters (1, 4, and 8) all have significant decadal changes, but they have not in Cluster 7. And the decadal change times also exhibit regional differences. The investigation of different‐duration CDDs in this study provides more information on droughts at different time scales in China.

Macroinvertebrate seedbank survival in pristine and nutrient-enriched intermittent streams and its contribution to flow phase communities

Intermittent stream research focuses mostly on pristine streams. The impacts of nutrient enrichment on invertebrate communities in these systems thus remains underexplored, especially in temperate climates. This study aimed to compare taxa survival during stream drying within pristine and nutrient-enriched sediment streambeds and to evaluate seedbank contribution for community recovery. Ten dry sediment subsamples were each collected from three streams of each nutrient status type. These were rehydrated for 60 days in laboratory with persisting and hatching invertebrates being recorded. Oligochaetes and molluscs were the most abundant; stoneflies and mayflies were common; caddisflies were represented by only a few specimens. The seedbank comprised of around one-third of taxa recorded during flow phases with slightly higher taxa numbers in nutrient-enriched streams. Moisture content positively affected seedbank taxa richness, while dry period duration decreased it. Taxa richness has a unimodal response to nutrient enrichment, with fine sediment proportion revealing no significant effect. Our results show a richer macroinvertebrate seedbank in drying sediments under moist conditions with mild nutrient enrichment, while raised nutrient levels limited macroinvertebrate survival. These results highlight the crucial role of seedbanks in community recovery of intermittent temperate streams, which will become more common with climate change.

Seasonal trend of climate variables in an area of the Caatinga phytogeographic domain

Wide variability in the rainfall regime and drought is characteristic of semi-arid regions. A better understanding of this variability can aid decision-making in the short, medium and long term. The aim of this study was to identify long-term patterns and trends in rainfall and temperature through the use of temporal patterns, in addition to assessing the duration of wet and dry periods. Daily historical series of rainfall and temperature for the district of Iguatu, Ceará were used. For rainfall, the annual and monthly climate normal (1974-2018) was calculated, in addition to the number of consecutive dry days (CDD) during the rainy season. The annual mean value for the maximum, mean, and minimum temperatures (1996-2017) was also calculated. Wide interannual variability in the rainfall was found, with very wet years (1985; 2009 and 2011) and very dry years (1979; 1983 and 1993) interspersed with periods of around average rainfall. When analysing the total occurrence of dry spells by class, it was found that events of from 5 to 10 days were the most frequent, and tended to reduce in number over the period under investigation. There was also an increase in the number of longer events, those over 16 days. Maximum annual temperatures show an increasing trend over the years, with minimum temperatures showing the smallest increases. It was concluded that extreme rainfall events are common, and alternate between rainy years and years of drought. The increase in maximum temperature and the reduction in rainfall express the extreme climate variability that may be a consequence of climate change.

Risk of short-term biodiversity loss under more persistent precipitation regimes.

Recent findings indicate that atmospheric warming increases the persistence of weather patterns in the mid-latitudes, resulting in sequences of longer dry and wet periods compared to historic averages. The alternation of progressively longer dry and wet extremes could increasingly select for species with a broad environmental tolerance. As a consequence, biodiversity may decline. Here we explore the relationship between the persistence of summer precipitation regimes and plant diversity by subjecting experimental grassland mesocosms to a gradient of dry-wet alternation frequencies whilst keeping the total precipitation constant. The gradient varied the duration of consecutive wet and dry periods, from 1 up to 60days with or without precipitation, over a total of 120days. An alternation of longer dry and wet spells led to a severe loss of species richness (up to -75% relative to the current rainfall pattern in W-Europe) and functional diversity (enhanced dominance of grasses relative to nitrogen (N)-fixers and non-N-fixing forbs). Loss of N-fixers and non-N-fixing forbs in severe treatments was linked to lower baseline competitive success and higher physiological sensitivity to changes in soil moisture compared to grasses. The extent of diversity losses also strongly depended on the timing of the dry and wet periods. Regimes in which long droughts (≥20days) coincided with above-average temperatures showed significantly more physiological plant stress over the experimental period, greater plant mortality, and impoverished communities by the end of the season. Across all regimes, the duration of the longest period below permanent wilting point was an accurate predictor of mortality across the communities, indicating that increasingly persistent precipitation regimes may reduce opportunities for drought stress alleviation. We conclude that without recruitment, which was precluded in this experiment, summer precipitation regimes with longer dry and wet spells will likely diminish plant diversity, at least in the short term.

Local urban risk assessment of dry and hot hazards for planning mitigation measures

With the change of global climate and increased urbanisation, urban dry and hot hazards is becoming a more urgent problem that may affect sustainable city development. In the case of pronounced increase of air temperature and duration of dry periods, cities may experience long-lasting heat waves, soil dryness, and water shortages that concern the urban population, ecosystems, and socio-economic sectors. The research investigates urban vulnerability towards compound dry and hot hazards in one of the largest Polish cities - Wrocław. The aim of the paper was the development of multi-hazard framework to establish a set of metrics for a hot and dry hazards monitoring system that would provide insights into better management and sustainable development of the city in the long run. The developed indicators and thresholds system for hazard assessment covers meteorological and hydrological drought indices, heat waves, long lasting dry spells, extremely hot days, cooling degree days and low flows identification procedures. Analysis of long-term variability of the indicators values including frequency and trend analysis were the basis for the estimation of hazard levels. The main socio-economic sectors were examined in terms of their vulnerabilities to dry and hot hazards with regard to the spatial variation of sensitive city components. A combination of the estimated hazard levels and the vulnerability of the respective city sectors supported with expert judgments provided a local multi-risks urban assessment matrix. Reducing risks of dry and hot hazards requires coherent actions including educational, organisational, and technical solutions.

Воспроизводительные качества дочерей быков айрширской породы – носителей гаплотипа фертильности АН1

An analysis of the reproductive qualities of the retired cows of Ayrshire breed, first calving in the period 2009–2016, was carried out, of which 7278 heads are daughters of bulls tested for carriage of the AH1 fertility haplotype: carriers (AH1C) – 16 heads and free (AH1F) – 41 heads at the number of offspring is 1391 and 5887 heads, respectively. It was found that the relative number of cows in the two analyzed groups did not differ – the difference did not exceed 1.0% (from –0,9 to +0,8%). It was found that abortions in the AH1C group are 0,13% lower, and stillbirths by 0.18% higher. The difference between the bulls and heifers born (in favor of bulls) is greater in the first group of animals (9,38 versus 7,64%). Data analysis showed that the age of the 1st insemination and calving was 0.4 months (p≤0,05) significantly later in the offspring of AH1C bulls. The number of insemination after the 1st calving in this group of animals is also significantly higher (p≤0,05) by 0,04 doses. Significant differences (p≤0,05) were revealed in the duration of intercalving and dry period for the highest lactation, which were 6 and 3 days, but on average for all completed lactations, a significant difference was not established for all studied characteristics. For the last completed lactation, there was a large difference in the number of milk days and days of pregnancy for incomplete lactation (–10 and –21 days, respectively). The term of productive use is 16 days longer in the group of descendants of bulls АН1С, bu t the difference is not significant. Productive use is 16 days longer in the group of bulls АН1С, but the difference is not significant. It can be concluded that the use of AH1C bulls for cows can be allowed if the economic effect of productivity covers the costs for a later period of the start of productive use (the cost of raising a heifer to the 1st calving), from the loss of calves (stillbirth) and due to a decrease in the number of heifers for herd reproduction and pedigree sale.

Variability of eight Algerian oleaster ecotypes (Olea europaea subsp. europaea var. sylvestris [Mill.] Lehr): pollen and exine morphology in relation to geo-climatic effect

Pollen characters of the Algerian oleaster (Olea europaea subsp. europaea var. sylvestris [Mill.] Lehr) from eight ecotypes were analysed to evaluate the geo-climatic effect of their environment. Samples were collected along an altitudinal gradient from western to central Algeria. Eighteen morphological characters of the pollen grains were studied using scanning electron microscopy (SEM). The results show significant inter-populations variability. The geo-climatic conditions, duration and timing of dry periods vary from one area to another. Depending on the area, the length of the dry period (P p ≤ 2T) coincides more or less with anthesis periods. No significant geo-climatic effects on exine parameters were detected, except for lumina density (LD) and mean lumina diameter (Lm). However, polar axis (P), pollen size index (PSI) and pollen colpis length (PCL) were found to be related to latitude, longitude and temperature. LD and Lm were strongly linked to the pollen parameters, resulting in variation in pollen shape and size. Depending on the geo-climatic conditions, three morphotypes appear. The morphotype from a site with high temperature, low humidity associated with a long dry period is characterised by small pollen size, low lumina surface area and high lumina density/100 μm2 and vice versa. The results indicate that the exine has played an important role in the environmental adaption in these wild populations.

Changes in the Characteristics of Dry and Wet Periods in Europe (1851–2015)

This study spanning the period 1851–2015 explores the spatial and temporal characteristics of dry and wet periods in Europe as well as their variability and changes. It is based on up to 220 stations with monthly precipitation time series that have a varying data availability within the study period. The stations are classified into eight regions with similar climate characteristics. Dry and wet periods are analyzed using the decile method as well as the modified Rainfall Anomaly Index mRAI at the 3-month timescale. Spatial extent, duration, and frequency of dry and wet periods show a large multi-decadal variability resulting in comparatively small long-term trends over the entirety of Europe for the study periods 1901–2015 and 1951–2015. Nonetheless, several sub-regions show distinct changes—with opposite signals for northern and southern Europe. Spatial extent and duration of dry periods generally decreased, while wet periods show increases throughout the 20th century—particularly in Scandinavia. A simultaneous increase in the frequency of severely dry and wet years, respectively, is observed since the 1980s. This indicates that temperature increases across Europe may be connected with an increasing frequency of extremes at both sides of the probability density function of precipitation.

Effect of Dry Period Duration on Udder Health, Milk Production and Body Condition of Jersey Crossbred Cows at Lower Gangetic Tropics

Background: Dry period duration of dairy cow is considered as an important factor to maintain udder health and milk production. Methods: To investigate the effect of dry period duration (DPD) on udder health, milk production and body condition of dairy cows at lower Gangetic tropics, observations were taken from 25 Jersey crossbred cows which were divided into 2 comparable group viz: 1st group (11 cows), having 50 to 60 days DPD and 2nd group (14 cows), having more than 60 days DPD. Result: Statistically analyzed data revealed that milk somatic cell count, MCMT, milk pH and EC were significantly (P less than 0.01) varied between two group from second month onwards and continue up to 4th months of lactation. Critical analysis of battery tests clearly confirmed the diagnosis for occurring of subclinical mastitis with poor udder health status in 2nd group. Total milk production/day/cow were almost similar in both group in first month but second month onwards significantly (P less than 0.01) higher milk production was recorded in 1st than 2nd group. The milk composition parameters revealed non-significant difference between groups whereas milk quality parameter significantly (P less than 0.01) better in 1st than 2nd group. Initial BCS of dry cow of both groups were similar. But BCS at calving was significantly (P less than 0.05) higher in 2nd than 1st group with higher negative changes in BCS % in 2nd group as compared to 1st group. It can be concluded that dry period duration of 50-60 days is better over to prolonged dry period (&gt;60 days). Suitable changes in BCS from dry period to calving is beneficial to get higher milk production, quality, better maintenance of body condition and udder health status of Jersey crossbred cows at tropical lower Gangetic region.

Impact of the Hydrogel Amendment and the Dry Period Duration on the Green Roof Retention Capacity

Abstract Climate changes as well as the urbanisation and economic development influence the characteristics of the stormwater runoff in the cities. The sealing of drainage basin surface leads to an increase of the runoff intensity, thereby decreasing the rainwater infiltration. This situation can lead to the risk of flooding in urban areas. Therefore, especially in great cities there is a need for application of such solutions that will support the operation of the sewage systems. The examples of such solutions are, among others, the green roofs. The paper presents the results of investigation of the water retention capacity of 4 green roof models containing following growing media: (1) the typical green roof substrate without any amendments, (2) the substrate with addition of about 1 % by weight of hydrogel (the cross-linked potassium polyacrylate), (3) the substrate containing about 0.25 % by weight of hydrogel, (4) the substrate with addition of expanded clay and perlite. The models were not vegetated in order to investigate only the water retention capacity of drainage elements and substrates. The water retention capacity of green roof models was investigated in the laboratory conditions with use of artificial precipitations simulated after diverse antecedent dry weather periods (ADWP) amounting to: 1, 2, 5, 7, and 12 days. The intensities of artificial precipitations were relatively high and ranged from 1.14 to 1.27 mm/min, whereas their durations ranged from 7.75 to 12.56 min. These values of intensities and durations corresponded to the design rainfall intensities calculated using Blaszczyk’s equation for annual rain depth equal to 600 mm and the return periods ranged from 5 to 15 years. The obtained results indicate that the water retention capacity of green roof models, expressed as the volumes (or depths) of rainwater retained within their structures, increases with an increase of ADWP. Results indicate that the relation between ADWP and the amount of water retained in the layers of green roofs in the case of relatively short antecedent dry weather periods provided for the analysis (from 1 to 7 days) may be approximately linear. The results of the one-way ANOVA indicate that in the case of all models there is a statistically significant difference between the values of retention depth for specified ADWP (p &lt; 0.001). During more than half of simulated precipitations, especially in the case of longer ADWPs lasting 5, 7, and 12 days the best water retention capacity had Model 3, with substrate containing about 0.25 % by weight of hydrogel. On the other hand, the results show that the weakest retention capacity had Model 2 (with substrate containing 1 % by weight of hydrogel). In the case of longer ADWPs (lasting 7 and 12 days) relatively weak water retention capacity had Model 4 (with substrate containing the addition of expanded clay and perlite). It can be concluded that too large amount of hydrogel added to the substrate can have an unfavourable impact on the water retention capacity of green roofs.