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- ItemDynamic cooling strategy based on individual animal response mitigated heat stress in dairy cows(Amsterdam : Elsevier, 2020) Levit, H.; Pinto, S.; Amon, T.; Gershon, E.; Kleinjan-Elazary, A.; Bloch, V.; Ben Meir, Y.A.; Portnik, Y.; Jacoby, S.; Arnin, A.; Miron, J.; Halachmi, I.Technological progress enables individual cow's temperatures to be measured in real time, using a bolus sensor inserted into the rumen (reticulorumen). However, current cooling systems often work at a constant schedule based on the ambient temperature and not on monitoring the animal itself. This study hypothesized that tailoring the cooling management to the cow's thermal reaction can mitigate heat stress. We propose a dynamic cooling system based on in vivo temperature sensors (boluses). Thus, cooling can be activated as needed and is thus most efficacious. A total of 30 lactating cows were randomly assigned to one of two groups; the groups received two different evaporative cooling regimes. A control group received cooling sessions on a preset time-based schedule, the method commonly used in farms; and an experimental group, which received the sensor-based (SB) cooling regime. Sensor-based was changed weekly according to the cow's reaction, as reflected in the changes in body temperatures from the previous week, as measured by reticulorumen boluses. The two treatment groups of cows had similar milk yields (44.7 kg/d), but those in the experimental group had higher milk fat (3.65 vs 3.43%), higher milk protein (3.23 vs 3.13%), higher energy corrected milk (ECM, 42.84 vs 41.48 kg/d), higher fat corrected milk 4%; (42.76 vs 41.34 kg/d), and shorter heat stress duration (5.03 vs 9.46 h/day) comparing to the control. Dry matter intake was higher in the experimental group. Daily visits to the feed trough were less frequent, with each visit lasting longer. The sensor-based cooling regime may be an effective tool to detect and ease heat stress in high-producing dairy cows during transitional seasons when heat load can become severe in arid and semi-arid zones.
- ItemChanges in the Spectrum of Free Fatty Acids in Blood Serum of Dairy Cows during a Prolonged Summer Heat Wave(Basel : MDPI, 2021) Mylostyvyi, Roman; Sejian, Veerasamy; Izhboldina, Olena; Kalinichenko, Olena; Karlova, Lina; Lesnovskay, Olena; Begma, Natalia; Marenkov, Oleh; Lykhach, Vadym; Midyk, Svitlana; Cherniy, Nikolay; Gutyj, Bogdan; Hoffmann, GundulaThis experiment was conducted to study the effect of a prolonged hot period on the fatty acid (FA) composition in blood serum of dairy cows. Eighteen multiparous Holstein cows were randomly assigned to the hyperthermia group (HYP, n = 8) in August (summer season) and the control group (CON, n = 10) in October (autumn season). Blood from animals of the HYP group was collected in one heat wave, which was preceded by a long period of heat stress (HS, temperature-humidity index (THI ≥ 72)). Blood from cows of the CON group was collected under thermal comfort conditions (THI < 68). The spectrum of free fatty acids (FFA) in the blood serum was analyzed by gas chromatography. The concentration of FFA increased, including saturated FAs and monounsaturated FAs, in the blood serum of cows under conditions of prolonged HS. This was associated with the mobilization of FA into the bloodstream from adipose tissue, as a consequence of negative energy balance. An increase in the ratio of n-6/n-3 polyunsaturated FAs may indicate biomembrane dysfunction and adversely affect dairy cows. This study showed that prolonged periods of heat can affect the FA composition of blood. How much this leads to changes in the FA composition of milk and the quality of food products remains to be seen in further research.
- ItemOpinion paper : Measuring livestock robustness and resilience : are we on the right track?(Amsterdam : Elsevier, 2019) Llonch, P.; Hoffmann, G.; Bodas, R.; Mirbach, D.; Verwer, C.; Haskell, M.J.[No abstract available]
- ItemSensor-based detection of the severity of hyperkeratosis in the teats of dairy cows(Basel : MDPI AG, 2018) Demba, S.; Hoffmann, G.; Ammon, C.; Rose-Meierhöfer, S.The aim of this study was to evaluate whether the severity of hyperkeratosis (HK) in the teats of dairy cows can be assessed by a dielectric measurement. The study focused on surveying the occurrence of hyperkeratosis in a total of 241 teats of lactating dairy cows. A scoring system consisting of four categories was used to macroscopically assess the severity of HK. Additionally, the dielectric constant (DC) of all teats with milkability was measured in a double iteration with the MoistureMeterD (Delfin Technologies, Kuopio, Finland) on four different days. The Spearman rank correlation coefficient revealed a negative correlation between the DC and HK score (rs = −0.55 to −0.36). The results of the regression analysis showed that the DC values differed significantly between healthy teat ends (≤2) and teat ends with HK (≥3). Thus, the non-invasive measurement of DC provides a promising method of objectively assessing the occurrence and severity of HK.
- ItemFarm water productivity in conventional and organic farming: Case studies of cow-calf farming systems in North Germany(Basel : MDPI AG, 2018) Vellenga, L.; Qualitz, G.; Drastig, K.The increase of organic agriculture in Germany raises the question of how water productivity differs from conventional agriculture. On three organic and two conventionally farming systems in Germany, water flows and water related indicators were quantified. Farm water productivity (FWP), farm water productivity of cow-calf production (FWPlivestock), and farm water productivity of food crop production (FWPfood crops) were calculated using the modeling software AgroHyd Farmmodel. The FWP was calculated on a mass and monetary basis. FWPlivestock showed the highest productivity on a mass basis occurring on a conventional farm with 0.09 kg m-3Winput, whereas one organic farm and one conventional farm showed the same results. On a monetary basis, organic cow-calf farming systems showed the highest FWPlivestock, with 0.28 € m-3Winput. Since the productivity of the farm depends strongly on the individual cultivated plants, FWPfood crops was compared at the level of the single crop. The results show furthermore that even with a precise examination of farm water productivity, a high bandwidth of temporal and local values are revealed on different farms: generic FWP for food crops and livestock are not within reach.
- ItemDifferences in optical properties of males and females pupae of Anastrepha fraterculus (Diptera: Tephritidae)(Bogotá : [Verlag nicht ermittelbar], 2021) Mundstock Jahnke, Simone; Gebbers, Robin; Capella Zanotta, Daniel; Intreβ, JoachimOne alternative to pesticide-based control of important fruit fly (Tephritidae) species is the sterile insect technique (SIT). SIT is based on mass releases of sterile males (subjected to radiation) to control a given pest population. For several important species such as Rhagoletis pomonella, Bractocera oleae and Anastrepha fraterculus, a technical challenge is to differentiate males from females in the pupal stage. Although for some species sterile females are released in the field, it is not desirable to release females from Anastrepha spp. as puncture damage may occur. Therefore, we investigated hyperspectral and RGB imaging to classify the sex in A. fraterculus pupae. We aimed to discriminate, through the description of RGB spectra and hyperespectral profiles, males and females in different stages of pupal development. Images of pupae of different degree-day (DD) development times were obtained. The hyperspectral profiles pupae of 288, 345 and 403 DD showed differences, indicating that pupal hue is altered throughout the development. In the NIR spectrum (800 to 1,700 nm), a higher reflectance between 1,100 and 1,400 nm was observed. In these bands differences in the spatial standard deviation of reflectance between males and females occur. As for the RGB images we observed differences in radiometric variation angle from the top to the basal part of the pupae. For females the radiometric variation angle was greater (26°) than for the males (15°). Thus, it is possible to determine discriminatory characteristics using the spectral profiles, imaging techniques and data analysis to discriminate the sexes.