Survey of Neospora caninum antibodies in dairy and beef cattle from five regions of the United States

Serum samples from 4,907 cows from 93 dairy and five beef herds were analyzed for antibodies to Neospora caninum by commercially available ELISA. The herds were recruited from 20 states and the territory of Puerto Rico. A questionnaire assessed the herd's abortion history and exposure risks to N. caninum. Results showed that 788 (16%) cows tested positive for antibodies to N. caninum. At least one positive animal was detected in 90% of the herds tested. The prevalence of cows seropositive to N. caninum varied from 2% to 65% among herds. Abortion rates ranging from 2% to 19% were reported. The epidemiologic data collected from the questionnaire suggested that the presence of farm dogs does not increase the risk of exposure of cows to N. caninum.     

Differential population dynamics of a coastal porpoise correspond to the fishing effort in a large estuarine system

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The influence of selected chemical compounds used in winter road maintenance on the active capillarity of soils

Purpose

Winter road maintenance involves the use of various chemical compounds which affect the active capillarity of soils. The main goal of the study was to determine a model to predict changes in the active capillarity of soils using distilled water and water solutions of chemical compounds which are used in winter road maintenance. The purpose of the first part of the experiment was to determine a model to predict changes in the height of capillarity rise and the rate of capillary rise with time. The second part of the experiment investigated how water solutions of selected chemical compounds altered the soils’ active capillarity as determined using distilled water.

Materials and methods

The research was carried out on three soils from deposits in west-central Poland, and their separated fractions. Active capillarity was investigated with the use of distilled water and 5 and 10 % solutions of ten chemical compounds used in winter road maintenance. The rate and height of capillary rise were measured in transparent vertical tubes, placed vertically in a glass tank into which the distilled water or solutions of chemical compounds were poured.

Results and discussion

The rate of capillary rise was decreasing as a function of time. After the first part of the experiment had been completed, an analysis was made of the statistical fit between the experimental data for capillary rise of distilled water in the studied soils and soil fractions, and the model described by the formula $ h(t) = {h_1} + {v_1} \times ln(t) $ , where h ₁ denoted the height of capillary rise in the first second, v ₁ denoted the rate of capillary rise, and t denoted time. High determination coefficients indicated a good fit of the model to the experimental data. In the second part of the study, it was found that solutions of chemical compounds caused a reduction in the active capillarity of the studied soils relative to the capillarity determined using distilled water. It was possible to determine a capillarity coefficient w _k so as to compare the capillary rises in soil of distilled water and of the various chemical compounds in 5 and 10 % solution. Analysis of the results showed that the capillarity coefficient w _k is a characteristic feature which depends on the type and concentration of the chemical subject to capillary action and on the type and fraction of soil.

Conclusions

The active capillarity of soil depends on the type and concentration of the capillary fluid such as distilled water or water solutions of chemical compounds used in winter road maintenance and other factors. The relation between the height of capillary rise h and time t can be described using the formula $ h(t) = {h_1} + {v_1} \times \ln (t) $ . The water solutions of chemical compounds used in winter road maintenance caused a reduction in the active capillarity of the studied soils relative to the capillarity determined using distilled water. It was found that the susceptibility of soil to capillary rise can be determined based on the capillarity coefficient w _k . This coefficient depends on the type and concentration of the chemical compound in the soil and on the soil type and fraction. The effect of these factors can be accounted for using the formula $ h(t) = {w_k} \times {h_1} + {w_k} \times {v_1} \times ln(t) $ .     

Poly(ADP-Ribose) Polymerase in Bovine Retained and Not Retained Placenta

Contents Poly(ADP-ribose) polymerase (PARP) synthesizes poly(ADP-ribose) in response to DNA strand breaks using NAD⁺ as a substrate. It leads to consequences for metabolism not only on a cellular level, but also on a tissue level, among others: NAD⁺ and ATP depletion. Retention of foetal membranes (RF) in cows is supposed to be connected with the imbalance between production and neutralization of reactive oxygen species, leading to oxidative damage to DNA, lipids and proteins. The aim of this preliminary study was to detect the presence of PARP in bovine placenta and to describe the enzyme with respect to type of placental tissue, time and mode of delivery. Placentomes, collected after spontaneous delivery or caesarian section, were divided into maternal and foetal parts of placenta, homogenized, and subjected to electrophoresis. Cows were divided into six groups as follows: (A) caesarian section before term with RF, (B) caesarian section before term without RF, (C) spontaneous delivery at term with RF, (D) spontaneous delivery at term without RF, (E) caesarian section at term with RF, (F) caesarian section at term without RF. PARP was detected by Western blotting using commercially available bovine anti PARP antibody. Bands referred to as bovine PARP standard were present in all examined tissues as well as the products of its cleavage. However, the patterns of bands were different with respect to type of tissue, time, and mode of delivery. Further experiments on detailed relationship between PARP activity and the process of releasing and retaining of bovine placenta are necessary.     

Regeneration patterns of the late-successional <Emphasis Type="Italic">Abies alba</Emphasis> Mill.: inhibition in monospecific stands and colonization in mixed stands

Key message

In Abies alba Mill. stands and mixed stands of A. alba and Picea abies L. (H. Karst), microsites neighbouring the trunks of adult trees were more conducive to A. alba regeneration. Although at the stand level, the effect of Fagus sylvatica L. was positive; the local effect of the adult F. sylvatica neighbourhood was insignificant. Hence, forming mixed stands with a fine-grained mosaic of admixed species might better facilitate natural regeneration of A. alba than monospecific stands.

Context

The establishment of natural regeneration in Abies alba Mill. stands is a slow, spatially heterogeneous and stochastic process. Recent studies based on inventory data indicate that A. alba more readily regenerates in mixed stands than in monospecific stands.

Aims

The objective was to examine how this positive association evidenced at the stand level operates on the scale of microsites with contrasting local species composition and stand density.

Methods

In 8 monospecific and 22 mixed stands with Fagus sylvatica L. or Picea abies L. (H. Karst), microsites with a contrasting density of A. alba seedlings were selected and compared in terms of local species composition, stand density, canopy characteristics and topsoil properties.

Results

In A. alba stands, seedling density was positively associated with the proximity of adult trees. In mixed stands of A. alba and P. abies, adult trees of both species exerted a positive effect on A. alba regeneration, but the P. abies neighbourhood influenced regeneration occurrence more strongly than the A. abies neighbourhood. In mixtures with F. sylvatica, however, the effect of local stand density and local species composition was not evidenced at all.

Conclusion

Although at the stand level, P. abies and F. sylvatica exert a positive effect on A. alba regeneration, on the microsite scale, their influences differ. In stands with a dominance of A. alba, the hampered seedling establishment in gaps may be considered an inhibitive effect that facilitates the emergence of other species.

     

Effect of tillage systems on pea crop infestation with weeds

In a multi-year experiment, weed infestation of pea crop in three tillage systems was analyzed: a) conventional tillage (CT), b) reduced tillage (RT), and c) no-tillage (NT), and in two terms: 1) at 2–3 pea leaves stage (23–25 stage in BBCH scale) and 2) at the flat pod stage (75–79 BBCH). Treatments conducted in the CT system included shallow ploughing and pre-winter ploughing in the autumn. In the RT system, both these treatments were replaced by double cultivation, whereas only glyphosate treatment was applied in the NT system. In both terms of weed infestation assessment, the highest number and air-dry weight of weeds were determined in the RT system, lower ones in CT and the lowest ones in the NT system. In the first term, the number of weeds m^?2 in the RT system was higher by 43.9% than in NT and by 26% than in CT system. Also in the second term was the weed number m^?2 in RT higher by 58.6% than in NT and by 27.9% than in CT. Tillage systems differentiated also weed mass in pea crop. In RT, it was 4-fold higher than in NT and over 2-fold higher than in CT.     

Home range establishment and utilization by reintroduced lions (Panthera leo) in a small South African wildlife reserve

Understanding of animal spatial behavior is essential for informed management decisions. In southern Africa, reintroduction of lions (Panthera leo) to small reserves (<1000 km²) has increased since the early 2000s, however studies on their ranging behavior in these enclosed systems remain lacking. We applied Time Local Convex Hull (T‐LoCoH) methods to study the home range establishment and utilization of 11 lions reintroduced to Dinokeng Game Reserve, South Africa, during 2011 through 2014. Lions established home ranges close to their release sites and during the following 3 years their home range sizes continued to increase, but in each individual case the size remained smaller than half of the reserve area (<70 km²). Space use strategies differed between the core and the entire home range, with higher frequency of visits found in core areas. Exceptionally high rates (>60 separate visits) around the largest dam and along rivers suggest the importance of water and its surrounding vegetation in the lions' space utilization pattern. The home range size did not differ with season or sex of the individuals, whereas shifts in locations of home ranges revealed differences in the response of the 2 sexes to territorial conflicts and management interventions. Our study shows a dynamic home range utilization pattern and highlights the importance of both fine‐scale space use patterns (frequency and duration of visits) and broad‐scale home range changes in understanding the ranging behavior of reintroduced animals.     

Effects of different diets on juvenile tench, Tinca tinca (L.) reared under controlled conditions

In a laboratory experiment at 28 °C, four commercial starters (Carp Starter, Uni Starter, Perla Plus, Asta) were fed intensively to 11-month-old juvenile tench Tinca tinca of initially 41 mm TL and 0.70 g BW, over a period of 120 days. Frozen chironomid larvae were fed to fish below satiation as a reference diet for comparison of the fish body chemical composition. Final survival rates of 99–100% and satisfactory growth were attained with all dry diets, ranging from 73.3 (Carp Starter) to 84.8 mm TL (Asta) and from 5.39 (Carp Starter) to 8.09 g BW (Perla Plus). External body deformities of up to 96.4% specimens appeared in those fed Uni Starter, Carp Starter and Perla Plus, whereas 0% were recorded for Asta and chironomids. Fish in groups with deformities showed significantly elevated lipid content in their bodies, lower ash content and higher condition coefficient values. Juveniles in groups without deformities did not substantially change lipid content, but the ash content increased. Thus, among four dry diets studied, only Asta starter can be fed effectively and safely to juvenile tench reared intensively under controlled conditions.