scholarly journals Vegetation resistance and resilience to a decade‐long dry period in the temperate grasslands in China

2021 ◽  
Author(s):  
Minqi Liang ◽  
Ruochen Cao ◽  
Kai Di ◽  
Daorui Han ◽  
Zhongmin Hu
Keyword(s):  
Dry Period ◽  
Temperate Grasslands

Effects of short dry period on complete-lactation milk and component yield in Holstein cows

2013 ◽  
Vol 84 (3) ◽  
pp. 349-359
Author(s):  
Masato NAKAMURA ◽  
Kei-ichi NAKAJIMA ◽  
Yuji TAKAHASHI ◽  
Hiroki SHIONO
Keyword(s):  
Holstein Cows ◽  
Dry Period

Effect of Bismuth Subnitrate Teat Canal Sealant with Ampicillin-Cloxacillin Combination in Control of Bovine Mastitis in Selected Farms in Kenya

2020 ◽  
Keyword(s):  
Risk Factors ◽  
Bacterial Pathogens ◽  
Animal Health ◽  
Bovine Mastitis ◽  
Test Group ◽  
Control Group ◽  
Dry Period ◽  
Coagulase Negative Staphylococci ◽  
Bismuth Subnitrate ◽  
Teat Canal

This study presents the results of effect of a combination of bismuth subnitrate teat canal sealant (Boviseal® -Bimeda® Animal Health, Ireland) and the antibiotic Ampicillin & Cloxacillin (Bovaclox® DC-Norbrook Laboratories Ltd-UK) when used during the dry period on occurrence of mastitis 100 days post-calving. The objectives of this study were: to determine the effect of Boviseal® teat canal sealant in combination with Bovaclox® DC in control of dairy cow mastitis 100 days after calving; to determine bacterial pathogens causing mastitis in the selected farms and to determine risk factors for occurrence of dairy mastitis in the selected farms. This controlled field trial was carried out in two Kenyan dairy farms: Chemusian Farm in Nakuru County and Gicheha Farm in Kiambu County. 156 dairy cows were used in the study. Healthy cows with no history of mastitis in their current lactation were recruited. They were randomly placed into either of the two study groups: the control and the test group. The Control group received Bovaclox® DC while the Test group received the Bovaclox® DC followed by Boviseal®. The cows were followed during the entire dry period and 100 days post-calving monitoring for mastitis occurrence. Cows in the control group were more susceptible to mastitis 100 days post-calving compared to cows in the treatment group (P<0.001, RR=4.4, OR=17.7). Of the bacterial pathogens, coagulase negative Staphylococci (CNS) were the most common pathogens isolated from mastitic milk at 34.6 % followed by Micrococcus spp. (9.0%). Other bacteria isolated were Streptococcus agalactiae (3.8%), Staphylococcus aureus (1.9%); Escherichia coli (0.6%) and various bacterial mixtures. Results of logistic regressions at P≤0.05 showed that farm, position of the quarter, type of barn floor and type of treatment were significantly associated with occurrence of mastitis. Cows in Gicheha farm whose barn floor was earthen, those cows in the control group and hindquarters were risk factors for mastitis (RR=1.5, 4.4 and 1.18 respectively). The results of this study showed that Bovaclox® DC + Boviseal® teat canal sealant combination applied during the dry period is more effective in controlling bovine mastitis 100 days post-calving compared to the use of Bovaclox® DC alone. The study thus recommends the use of Bovaclox® DC + Boviseal® dry cow combination for control of bovine mastitis.

Trophic Cascades in Grasslands

2018 ◽  
Author(s):  
Brian J. Wilsey
Keyword(s):  
Indirect Effects ◽  
Prey Species ◽  
Trophic Levels ◽  
Herbaceous Plant ◽  
Direct Effects ◽  
Temperate Grasslands ◽  
Cascading Effect ◽  
Top Predators ◽  
Invertebrate Predators ◽  
Ecology Of Fear

Top predators have effects that can ‘cascade down’ on lower trophic levels. Because of this cascading effect, it matters how many trophic levels are present. Predators are either ‘sit and wait’ or ‘active’. Wolves are top predators in temperate grasslands and can alter species composition of smaller-sized predators, prey, and woody and herbaceous plant species, either through direct effects or indirect effects (‘Ecology of Fear’). In human derived grasslands, invertebrate predators fill a similar ecological role as wolves. Migrating populations of herbivores tend to be more limited by food than non-migratory populations. The phenology and synchrony of births vary among prey species in a way that is consistent with an adaptation to predation. Precocious species have highly synchronous birth dates to satiate predators. Non-precocious species (‘hiders’) have asynchronous births. Results from studies that manipulate both predators and food support the hypothesis that bottom-up and top-down effects interact.

scholarly journals The effect of metabolism on the course of labor and the postpartum period in highly productive cows

2020 ◽  
Vol 17 ◽  
pp. 00256
Author(s):  
Murat Baimishev ◽  
Sergey Eremin ◽  
Kirill Plemyashov ◽  
Hamidulla Baimishev ◽  
Igor Konopeltsev ◽  
...  
Keyword(s):  
Lipid Metabolism ◽  
Postpartum Period ◽  
Early Stage ◽  
Antioxidant Properties ◽  
Antioxidant Systems ◽  
Dry Period ◽  
Blood Samples ◽  
Start Up ◽  
Significant Difference ◽  
Duration Of Pregnancy

The purpose of the research is to determine the etiopathogenesis of reproductive dysfunction in highly productive cows. For this, one group of cows was formed on the principle of paranalogs in the amount of 37 animals inseminated in the first sexual hunt after calving, followed by taking blood samples from them using the Monovet system, considering the duration of pregnancy. During the start-up period, blood was taken 1–4 days before calving and on the first day after calving. A total of 253 blood samples were examined. Subsequently, depending on the effectiveness of insemination, animals were divided into two groups. The first group included inseminated cows after the first insemination (20 animals), the second group included 17 unfertilized cows after the first insemination. Subsequently, blood was taken from animals considering the course of childbirth and the postpartum period. Blood counts were studied according to generally accepted methods using certified equipment. The study found that at an early stage of pregnancy, cows have a significant difference in lipid metabolism and in their peroxidation, in the state of antioxidant systems compared to unstable animals. In the process of pregnancy development in cows, there is a decrease in the level of total lipids and their class, and the accumulation of products of transoxidation of lipids is reduced. In animals with retention of the placenta, a low lipid metabolism and a higher level of peroxidation were established already in the dry period. After calving, this difference increases. The obtained data can be used to develop an algorithm for the prevention of postpartum complications in cows by using substances with antioxidant properties.

scholarly journals Desiccation time and rainfall control gaseous carbon fluxes in an intermittent stream

2021 ◽  
Author(s):  
Maria Isabel Arce ◽  
Mia M. Bengtsson ◽  
Daniel von Schiller ◽  
Dominik Zak ◽  
Jana Täumer ◽  
...  
Keyword(s):  
Water Soluble ◽  
Intermittent Flow ◽  
Dry Period ◽  
Intermittent Stream ◽  
Aerobic Activity ◽  
Water Soluble Organic Carbon ◽  
Soluble Organic Carbon ◽  
Microbial C ◽  
Global Biogeochemical Cycles ◽  
The Impact

AbstractDroughts are recognized to impact global biogeochemical cycles. However, the implication of desiccation on in-stream carbon (C) cycling is not well understood yet. We subjected sediments from a lowland, organic rich intermittent stream to experimental desiccation over a 9-week-period to investigate temporal changes in microbial functional traits in relation to their redox requirements, carbon dioxide (CO2) and methane (CH4) fluxes and water-soluble organic carbon (WSOC). Concurrently, the implications of rewetting by simulated short rainfalls (4 and 21 mm) on gaseous C fluxes were tested. Early desiccation triggered dynamic fluxes of CO2 and CH4 with peak values of 383 and 30 mg C m−2 h−1 (mean ± SD), respectively, likely in response to enhanced aerobic mineralization and accelerated evasion. At longer desiccation, CH4 dropped abruptly, likely because of reduced abundance of anaerobic microbial traits. The CO2 fluxes ceased later, suggesting aerobic activity was constrained only by extended desiccation over time. We found that rainfall boosted fluxes of CO2, which were modulated by rainfall size and the preceding desiccation time. Desiccation also reduced the amount of WSOC and the proportion of labile compounds leaching from sediment. It remains questionable to which extent changes of the sediment C pool are influenced by respiration processes, microbial C uptake and cell lysis due to drying-rewetting cycles. We highlight that the severity of the dry period, which is controlled by its duration and the presence of precipitation events, needs detailed consideration to estimate the impact of intermittent flow on global riverine C fluxes.

scholarly journals PSVII-17 Program Chair Poster Pick: Reproductive function of cows depending on lipid metabolism

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 293-294
Author(s):  
Murat Baymishev ◽  
Sergey Eremin ◽  
Kirill Plemyashov ◽  
Khamidulla Baymishev ◽  
Igor Konopel’tsev ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Live Weight ◽  
Reproductive Function ◽  
Serum Levels ◽  
Total Serum ◽  
Dry Period ◽  
Lipid Peroxidation Products ◽  
Synthetic Function ◽  
The Difference ◽  
Oxidized Products

Abstract The aim of the study was to determine the etiopathogenesis of reproductive dysfunction in highly productive cows. Studies were conducted on cows of black-motley breed, aged 3–5 lactations, with a live weight of 480–520 kg. Cows were divided into two groups. The first group included 20 cows effective inseminated after the first insemination. The second group included 17 cows that did not fertilize after the first insemination. Blood samples (n = 253) were taken from 4–7; 14–17; 24–34; 35–50; 88–95; 195–210 days of pregnancy; during the beginning of dry period (DP); 1–4 days before calving and on the first day after calving. The content of total serum lipids in pregnant animals was 15.8% higher compared to unfertilized animals. In non-pregnant cows, a decrease in free cholesterol (by 28.65%), especially in its ether-bound fraction (14.91%), indicates a lower synthetic function of the liver, which is confirmed by the low serum levels of vitamins A and E (a difference of 11.3 and 23.65%). The DP was characterized by a significant increase in the products of lipid peroxidation - malondialdehyde by 12–17%, diene and triene conjugates - by 10–15 and 8–15%, respectively, and 1–4 days before calving in cows, which subsequently had a pathological calving, in particular - retention of placenta (5 cows), were characterized by an increased content in the blood plasma of lipid peroxidation products. Thus, the difference in the number of dienes, trienes, and malondialdehyde products was 14.0, 12.0, and 23.5%, compared with animals without obstetric pathology. On the first day after calving, this difference increased even more. Cows with retention of placenta had a significantly higher level of lipid peroxidation products and were characterized by a predominance of oxidized products over the antiradical thiol disulfide and ascorbate systems restored in the antioxidant balance.

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