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Dry Period or Early Lactation — Time of Onset and Associated Risk Factors for Intramammary Infections in Dairy Cows

Dry Period or Early Lactation — Time of Onset and Associated Risk Factors for Intramammary Infections in Dairy Cows

quarters were infected 17 ± 3 days compared to 3 ± 1 days postpartum. New infections can be traced to non-aureus staphylococci and Staphylococcus aureus from dry-off up until 3 ± 1 days postpartum, and to non-aureus staphylococci, Staphylococcus aureus and Streptococcus uberis, after calving. In total, 88.7% of the infected quarters showed new infections with another pathogen species 3 ± 1 days postpartum than at dry-off, and 89.2% of the quarters 17 ± 3 days postpartum than 3 ± 1 days postpartum. In conclusion, the early lactation has just as important an influence on intramammary infections postpartum in dairy cows as the dry period. There is the possibility that udder quarters eliminate pathogens during the early lactation, especially during the dry period. However, there is also the danger that new infections manifest, with a large proportion of new infections occurring after calving. Thus, additional control strategies are of great importance to prevent new infections occurring during early lactation as well as during the dry period to reduce negative effects on milk yield and culling hazards in dairy cows by minimizing the associated risk factors.
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Effects of dietary supplementation with Urea molasses multi-nutrient block in local Ethiopian and crossbred dairy cows in North-western Ethiopia / Tekeba Eshetie

Effects of dietary supplementation with Urea molasses multi-nutrient block in local Ethiopian and crossbred dairy cows in North-western Ethiopia / Tekeba Eshetie

Figure 3. Milk energy offtake of dairy cows in two different livestock production systems Irrespective of the production system, UMMB supplementation also substantially improved the estimated body weight gain of dairy cows as compared to non-supplemented cows (Table 8): While the unsupplemented cows slightly lost body weight, the UMMB supplementation led to a positive change in estimated body weight, which is remarkable, given that the cows were in their early stages of lactation. Similar to this finding, UMMB supplementation exerted a positive effect on body weight gain irrespective of the breed in the previous on-station experiments (Table 4 and 6). A similar response to consumption of urea-molasses blocks was also reported for growing buffalos (Jian-Xin Liu et al., 2007). The positive influence of the UMMB supplementation on estimated body weight gain is paralleled by a significant (P < 0.05) 0.4 to 0.5 score points improvement of BCS of dairy cows in RS and PU production systems, respectively. Contrary to these findings, UMMB supplementation failed to show positive effects on body weight and body condition of crossbred dairy cows under smallholder conditions in Vietnam (Doan Duc Vu et al., 1999). As suggested by the authors, one reason for this may have been a continuous selection for increased milk yield rather than body weight and a concomitant priority in nutrient partitioning.
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Investigations on the replacement of maize products in rations for dairy cows and fattening bulls

Investigations on the replacement of maize products in rations for dairy cows and fattening bulls

In week 4 and week 8 of the trial urine samples were taken to determine net acid-base excretion (NABE). Higher values (p<0.05) were obtained for group alfalfa silage at both sampling dates. More- over, values below reference values were seen more often in cows of the maize silage group than in other groups. There is a correlation between NABE and the fibre intake in dairy cows (S cholz et al., 2010) and therefore the differences may be discussed as a benefit of supply of dietary structure due to feeding of alfalfa. However, at given high dietary fibre concentrations differences may also be a consequence of differences in dietary cation-anion balance, which is also known to influence NABE (S cholz et al., 2010). From the result of the present trial it can be concluded that alfafa silage is suit- able as a roughage source in high yielding dairy cows, even if proportion of alfalfa in the total diet is high. Benefits of supply of structural fibre may be seen in diets with a high starch concentration. Characterisation of influence of alfalfa on feed intake in relation to its energy concentration should be further investigated.
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Nutritional strategies to optimize efficiency of nitrogen use by lactating dairy cows - kumulative Dissertation

Nutritional strategies to optimize efficiency of nitrogen use by lactating dairy cows - kumulative Dissertation

Table 1: A comparison of the essential amino acid profiles of lean body tissue, milk protein, ruminal bacteria and protozoa, and common feedstuffs (data from literature surveys by Lebzien 1997 a ; Fox et al. 2004 b ; all other values: DEGUSSA 2001) ………….18 Table 2: Content of ruminally undegradable protein (% of crude protein) of different protein feeds (Universität Hohenheim - Dokumentationsstelle 1997) ……………………19 Table 3: Chemical fractionation of the crude protein of feedstuffs for ruminants (Licitra et al. 1996) ………………………………………………………………………….20 Table 4: Estimation of methionine supply as related to milk yield or varying methionine utilization (according to Jochmann et al. 1996) ………………………………….25 Table 5: Effect of supplemental rumen-protected lysine, methionine or both amino acids added to the ration of lactating dairy cows on the average plasma concentration of urea and free amino acids (according to Trinacty et al. 2009) …………………….29 Table 6: Changes of milk protein concentration (percentage units) and milk yield (kg ECM) in response to rumen-protected methionine supplementation relative to the unsupplemented control ration ……………………………………………………32 Table 7: Trials with one or more supplemented (rumen-protected) methionine-/lysine-
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Analysis of hepatic transcript profile and plasma lipid profile in early lactating dairy cows fed grape seed and grape marc meal extract

Analysis of hepatic transcript profile and plasma lipid profile in early lactating dairy cows fed grape seed and grape marc meal extract

For this investigation, we used liver and plasma samples collected at 1 week postpartum of an experiment with dairy cows [13]. At this time point, both metabolic and inflammatory stress markers, such as plasma NEFA, plasma BHBA and hepatic mRNA concentrations of acute phase proteins (APPs), were increased most com- pared to later sampling time points (week 3 and week 5) in this study and another study [13, 24]. In this experi- ment, 28 Holstein cows with an average parity number of 2.8 were used as experimental animals. The experi- ment was conducted at the Educational and Research Centre for Animal Husbandry Hofgut Neumühle in Rhineland-Palatinate (Münchweiler an der Alsenz, Germany); the experimental protocol was approved by the Provincial Government of Coblenz, Germany (23 177–07/G12–20–074). The cows were assigned into 2 experimental groups, either a control group (n = 14) or a group supplemented with GSGME (GSGME group; n = 14), each consisting of 10 multiparous and 4 primiparous cows and having a similar average par- ity number (control group: 2.8, GSGME group: 2.9). In the period between week 3 prepartum and calving, a total mixed ration (TMR) was fed which was calcu- lated to meet the demand of net energy (NE) and crude protein (CP) requirement of a dry cow with a BW of 650 kg and an assumed dry matter intake (DMI) of 12 kg/d, according to the German Society of Nutrition Physiology [25]. After calving, all ani- mals were offered a basal TMR calculated to meet the demand of net energy and CP requirement for producing 34 kg of milk, with an assumed daily DMI of 22 kg [13]. Feed components were collected fort- nightly and analyzed according to the official methods of Verband der Deutschen Landwirtschaftli- chen Untersuchungs- und Forschungsanstalten [26]. The analyzed chemical composition of the TMR of- fered during dry period and lactation was in average of control and GSGME group as follows (per kg DM): 6.5 and 6.8 MJ NE L , 140 and 166 g CP, 383
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Relationships between feeding and microbial faeces indices in dairy cows at different milk yield levels

Relationships between feeding and microbial faeces indices in dairy cows at different milk yield levels

and non-lactating. Five cows were randomly selected per treatment on each farm, i.e. a total of 60 faecal samples were taken for this study. At Wolkramshausen (Thuringia) and Oederan (Saxonia), the cows were fed with a total mixed ration based on maize silage. The dairy herd at Wolkramshausen included 371 dairy cows, yielding on average 33.3 kg milk cow -1 d -1 . At Oederan, a herd of 930 cows produced on average 28.9 kg milk cow -1 d -1 . At Rotenburg (Schleswig-Holstein), a herd of 137 animals was fed with a mixed ration of grass and maize silage and yielded on average 27.6 kg milk cow -1 d -1 . The diets of low- and high-yield cows were supplemented with concentrate, individually allocated by transponder control. At Aurich (Lower Saxony), a herd of 146 cows produced an average yield of 24.0 kg milk cow -1 d -1 . They were fed with a mixed ration based on grass and maize silage in the stable in addition to daily grazing during the vegetation period. Low-yield and high-yield cows received different con- centrates, individually allocated by transponder control.
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How to measure dairy cows´ responsiveness towards humans in breeding and welfare assessment? A comparison of selected behavioural measures and existing breeding traits

How to measure dairy cows´ responsiveness towards humans in breeding and welfare assessment? A comparison of selected behavioural measures and existing breeding traits

found in larger data sets of Canadian dairy cows (Sewalem et al., 2011) and Swiss dairy cows (Ilahi and Kadarmideen, 2004). It is possible that this tendency towards intermediate scores contributed to an apparently closer correlation. Additionally, infrequent contact to individual cows due to herd sizes and milking systems has probably played a part in improper allocation of MS and MT scores: six of the 19 farms, from which data on cows’ MS and MT was available, worked with herd sizes > 100, and further six farms worked with automatic milking systems (AMS). In addition, animal owners might be less experienced in scoring on a standardised scale than independent experts. Animal owners may also be biased by their generalised assessment of a cow’s quality and performance. This would explain the non-significant weak correlation between MS and measured average milk flow (AMF), although both traits refer to milk flow linearly from slow to fast milking. However, it should be taken into account that the sample size ( n = 38 cows) was lower in relation to high sample sizes in behavioural measures at animal level (n = 582-1,890 cows).
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Mismatch of Glucose Allocation between Different Life Functions in the Transition Period of Dairy Cows

Mismatch of Glucose Allocation between Different Life Functions in the Transition Period of Dairy Cows

Further evidence for an antagonistic, yet dysbalanced relationship between metabolic pathways involved in adaptation to lactation and adaptation to inflammation is derived from studies examining the effect of the characteristic endocrine alterations required for high milk yields. Compared to low or medium genetic merit cows, high genetic merit cows show lower plasma concentrations of glucose, insulin and IGF-1, as well as higher plasma concentrations of GH [ 151 , 152 ], while insulin resistance is increased [ 63 , 153 – 155 ]. As described above, hypoinsulinemia favors glucose uptake in both immune cells and MEC because these cells are not dependent on insulin whereas glucose uptake to insulin-dependent cells like adipose and muscle cells is reduced [ 67 ]. However, hypoinsulinemia also mitigates stimulating effects of insulin on the rate of glucose utilization and phagocytosis in immune cells [ 156 , 157 ]. Moreover, increased GH-resistance is associated to selection for milk production and might contribute to the dysbalanced allocation of resources between MEC and immune cells in dairy cows. While GH exerts its mammogenic and galactopoietic effects directly in the mammary gland, either through GHR or through mammary IGF-1 production [ 158 , 159 ], many of the immune-stimulating effects attributed to GH are mediated indirectly through induction of hepatic IGF-1 production [ 160 ]. However, IGF-1 production in the liver is blunted through hepatic GH-resistance during early lactation [ 47 ]. Interestingly, it was shown that different breeds selected for milk production (Holstein-Friesian and Guernsey) showed similar decreases in GHR1A mRNA expression [ 161 ], whereas a comparison between Holstein-Friesian and beef cattle revealed decreases in the expression of GHR1A in dairy cows only [ 162 ].
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Up-regulation of endoplasmic reticulum stress induced genes of the unfolded protein response in the liver of periparturient dairy cows

Up-regulation of endoplasmic reticulum stress induced genes of the unfolded protein response in the liver of periparturient dairy cows

liver of dairy cows at early lactation (Figure 2). It has been assumed that mRNA concentrations of ER chaperons, ERAD components, such as BiP, HERP, WARS, PDIA4, P58 IPK , EDEM1, XBP1, and ATF4, or genes, that are in- volved in the induction of apoptosis, such as Chop or cas- pases, are reliable markers of ER stress [22-24,27,37]. Thus, the present study strongly suggests the presence of ER stress in the liver of dairy cows during early lactation, which was associated with induction of the UPR. This sug- gestion is supported by the present finding, that the mRNA concentration of sXBP1 in the liver was increased at 1 wk postpartum, indicative of an increased XBP1 spli- cing, which is considered a hallmark of ER stress [8]. The observed activation of XBP1 by unconventional splicing of XBP1 mRNA 1 wk postpartum agrees with a recent study of Loor [38] who found an up-regulation of 39 target genes of XBP1 in the liver of dairy cows during the transi- tion from late pregnancy to lactation by transcriptome analysis.
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Expression of genes involved in hepatic carnitine synthesis and uptake in dairy cows in the transition period and at different stages of lactation

Expression of genes involved in hepatic carnitine synthesis and uptake in dairy cows in the transition period and at different stages of lactation

In dairy cows, the transition from late pregnancy to early lactation is associated with severe metabolic adap- tations. Production of milk leads to a strong increase of the energy requirement, which however cannot be met as the food intake capacity is limited. Thus, during early lactation, dairy cows are typically in a negative energy balance which is compensated by the mobilization of non-esterified fatty acids (NEFA) from adipose tissue. NEFA are transported by binding with serum albumin and are taken up by fatty acid transporters into tissues, mainly the liver [11]. Studies in rodents have clearly established that NEFA taken up into the liver are able to bind to and activate PPARA [12,13]. In contrast to the large body of literature in non-ruminants, very little work has been conducted to define the specific effects or mechanisms of PPARA in cattle liver so far. However, a recent study using clofibrate as a synthetic agonist in weaned calves showed that PPARA is functional in cat- tle liver [14]. Moreover, it has been shown that long chain fatty acids are able to activate PPARA also in bovine cells [15]. In accordance with this finding, a negative energy balance in dairy cattle, either occurring physiologically during early lactation or induced by feed restriction, was associated with an up-regulation of sev- eral PPARA target genes involved in fatty acid oxidation or ketosis in the liver, indicative of an activation of PPARA [16,17].
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Effects of grape pomace and a polyphenolic plant product during the transition period of high-yielding dairy cows - kumulative Dissertation

Effects of grape pomace and a polyphenolic plant product during the transition period of high-yielding dairy cows - kumulative Dissertation

key factors of the metabolic status of dairy cows during early lactation [20]. Imhashly et al. [88] recently showed, using lipidomic analysis of plasma, that concentrations of some unsaturated PC, LPC and SM species (such as PC 36:4, PC 36:5, PC 36:6, LPC 18:1, LPC 18:2, LPC 18:3, SM 39:1, SM 43:3) in dairy cows are continuously increasing after birth. A common feature of these phospholipids is their requirement for the secretion of hepatic TAG as very low-density lipoprotein particles. Thus, an increased for- mation and secretion of these phospholipids after birth has been regarded as a means of the liver to prevent accu- mulation of lipids [88]. In the present study, we observed that concentrations of all the individual phospholipids, and even their molecular species, in plasma of dairy cows in week 1 postpartum are not influenced by feeding GSGME. As the greatest part of plasma phospholipids is synthesized in the liver, this finding strongly suggests that phospholipid metabolism in the liver was not influenced by polyphenols from GSGME. The finding that fatty acid moieties of plasma phospholipids were also not changed in the group of cows supplemented with GSGME indi- cates that polyphenols also did not influence hepatic de- saturation and elongation of fatty acids. This finding is of relevance as the fatty acid composition of phospholipids not only influences properties of cellular membranes [89], but certain phospholipid-bound fatty acids such as arachidonic acid are serving also as precursors for the synthesis of pro-inflammatory eicosanoids [90]. The finding that supplementation of GSGME did not influence the concentrations of free cholesterol and cholesterol esters indicates that polyphenols do not modify hepatic cholesterol metabolism. This finding agrees with our recent study which showed that GSGME does not influence hepatic cholesterol concen- tration [13]. Ceramide and ceramide-derived sphingoli- pids are structural components of membranes. In plasma, ceramides are transported as components of low-density lipoproteins of hepatic origin [91]. Cera- mides are of physiological relevance as their plasma concentrations have been linked to insulin resistance, oxidative stress, and inflammation [22, 92–94], condi- tions which are commonly observed in dairy cows dur- ing the transition period. Recently, Rico et al. [91] have shown that overweight dairy cows have increased plasma concentrations of ceramides and these are closely linked with the progression of insulin resist- ance. These authors suggested that ceramides may have a fundamental role in the homeorhetic adaptation to early lactation in dairy cows. Our lipidomic analysis revealed that polyphenols from GSGME do not influence plasma concentrations and the molecular profile of cera- mides in plasma. Thus, we conclude that beneficial effects of GSGME on inflammation and ER stress in the liver were independent of metabolism of ceramides.
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Metabolic disorders in the transition period indicate that the dairy cows' ability to adapt is overstressed

Metabolic disorders in the transition period indicate that the dairy cows' ability to adapt is overstressed

being disturbed” [ 14 ]. With respect to agricultural systems, “resilience thinking focuses on enabling a system to cope with unexpected change and disturbance” [ 15 ]. In the case of dairy cows, this term might be used in describing the ability of an animal to regain a state within a normal physiological range and/or to recover from disorders and diseases. The term “adaptation” is used in biology in relation to how living beings adjust to their environments. In the face of changes and disturbances, reactions of organisms lead to changes in the composition of their system which remain in force and are more or less permanent. According to Di Paolo [ 16 ], adaptivity is a system’s capacity to regulate, according to the circumstances, its states and its relation to the environment with the result that, if the states are sufficiently close to the boundary of viability, (1) tendencies are distinguished and acted upon depending on whether the states will approach or recede from the boundary and, as a consequence; (2) tendencies of the first kind are moved closer to or transformed into tendencies of the second and so future states are prevented from reaching the boundary with an outward velocity. The specific rate of function for each organ, describing the specific range where it is able to operate, is specified by the regulatory system according to both environmental and internal conditions. A process becomes malfunctional when—due to the fact that its particular qualities limit its range of modulation—it is unable to do what the regulatory (sub)system “tells” it to do within the framework of a specific regime of self-maintenance. Diseases and disorders can be understood as negative bodily occurrences where a part of the organism fails to appropriately perform one of its biological functions [ 17 ]. Biological functions are interpreted as specific causal effects of a part that contributes to a complex web of mutual interactions, which, in turn, maintain the organization and, consequently, the part itself. Generally speaking, a well-adapted system is a set of interacting and interdependent entities, forming an integrated whole that together are able to respond to environmental changes or changes in the interacting parts.
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Fecal Cortisol Metabolites in Dairy Cows: A Cross-Sectional Exploration of Associations with Animal, Stockperson, and Farm Characteristics

Fecal Cortisol Metabolites in Dairy Cows: A Cross-Sectional Exploration of Associations with Animal, Stockperson, and Farm Characteristics

Received: 3 August 2020; Accepted: 22 September 2020; Published: 1 October 2020    Simple Summary: Dairy cows are exposed to various potentially stressful situations in the daily farm routine, which might considerably impair their welfare and performance. On 25 German organic dairy farms, we explored associations of cows’ physiological stress levels by means of cortisol metabolite concentrations in feces (1) with different potentially influencing farm factors including human–animal contact, (2) cows’ fear behaviors towards humans, and (3) milk production and udder health. Cortisol metabolite levels were decreased on farms that did not separate diseased cows, possibly reflecting less regrouping stress. Levels were also lower on farms with straw yards compared to raised cubicles, and on farms with generous compared to suboptimal lying space, underlining the importance of resting comfort for cattle. Increased human–animal contact was associated with decreased cortisol metabolite levels. However, against expectations, levels were higher, when the farm provided concentrate feed by hand and habituated young cows to milking, requiring specific experimental investigations to draw conclusions on causal associations.
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Behavioural response of dairy cows with and without calf-contact to hair of own and alien calves presented in the milking parlour

Behavioural response of dairy cows with and without calf-contact to hair of own and alien calves presented in the milking parlour

4 than pheromones is responsible for the development of a selective recognition of the lamb (reviewed by Kendrick et al., 1997). Odours of faeces or urine play a minor role in maternal recognition in ewes (Alexander and Stevens, 1981, 1982/83). The theory that lambs are “labelled” by their mother’s milk or saliva could not be substantiated (Alexander and Stevens, 1982/83; Lévy et al., 1991). Textile materials, with which animals were rubbed or which were worn by an animal or human, have been successfully used in fostering (beef cattle: Dunn et al., 1987; ewes: Martin et al., 1987) and discrimination tests (ewes: Alexander and Stevens, 1982/83; humans: Porter and Cernoch, 1983; Porter and Moore, 1981, Lundström et al., 2009; European storm petrel sea birds: Bonadonna and Sanz-Aguilar, 2012). Therefore, Barth et al. (2010) rubbed calves with cotton cloths, which were used to reproduce an olfactory stimulation in dairy cows in the milking parlour. However, neither behavioural responses were detected nor an increase in milk ejection achieved. It remained unclear whether the cows did not perceive the stimulus or merely did not react to it. Therefore, in this study we attempted to intensify the calf-odour of samples presented to cows in the milking parlour. A source of odour, which worked well in choice tests with ewes, was wool of different body regions (Alexander, 1978; Alexander and Stevens, 1982/83). For acceptance at the udder, the odour from the anogenital region of the lambs was most important (Alexander et al., 1983). Therefore, calf hair from the anogenital region and hind limbs was used as the source of odour in this study to elicit a behavioural response in cows during milking. As proffering each cow the hair of her own calf is too labour intensive for normal farm practices, the response to alien calf hair is of significant interest. This pilot study addressed the
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Antimicrobial Susceptibility of Fecal Escherichia coli Isolates in Dairy Cows Following Systemic Treatment with Ceftiofur or Penicillin

Antimicrobial Susceptibility of Fecal Escherichia coli Isolates in Dairy Cows Following Systemic Treatment with Ceftiofur or Penicillin

and propagate genetic elements coding for resistance that are subsequently acquired by human pathogens (Angulo et al., 2004; Wassenaar, 2005). One drug of concern is ceftiofur, a third generation cephalosporin. Systemic use of ceftiofur against common diseases of dairy cows is attractive because milk from treated individuals need not be withheld from marketing and withholding periods for meat are short (Tragesser et al., 2006). In human medicine, third generation cephalosporins are valued for treating serious or life threatening infections. Therefore, the use of ceftiofur in dairy cows is seen as a potential threat to the ability to cure a range of life-threatening infections in people (Allen and Poppe, 2002). There are special concerns about zoonotic forms of multi-drug resistant Salmonella acquiring resistance to third generation cephalosporins because dairy cattle are one of the reservoirs for these pathogens (Frye and Fedorka-Cray, 2007; Whichard et al., 2007). In response to these issues the United States Food and Drug Administration recently evaluated whether ceftiofur use should be modified to further protect consumers (FDA, 2009).
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Identification and development of measures suitable as potential breeding traits regarding dairy cows´ reactivity towards humans

Identification and development of measures suitable as potential breeding traits regarding dairy cows´ reactivity towards humans

Avoidance distances (AD), tolerance to tactile interaction (TTI), release behaviour (RB) and qualitative behaviour assessment (QBA) were found to be promising measures of dairy cows’ reactivity towards humans, being suitable as breeding traits in terms of practical application and reliability. Good to very good agreement between trained observers could be reached, for TTI, RB and QBA also within one observer after seven months. They therefore proved to be sufficiently feasible to apply. Significant moderate inter-test correlations between ADfeed, TTI and RB suggest that they partly reflect similar and partly different aspects of the human animal relationship. Higher correlations between the two AD measures on the one hand and between TTI, RB and QBA on the other hand indicate a distinction between distance and handling measures.
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Are Severe Mastitis Cases in Dairy Cows Associated with Bacteremia?

Are Severe Mastitis Cases in Dairy Cows Associated with Bacteremia?

2.1. Study Design A cross-sectional study was carried out from January 2017 to December 2017 on two commercial dairy farms in Mecklenburg-Western Pomerania, Germany. The herd size varied between 1000 and 1200 Holstein-Friesian dairy cows. The 305-d milk yield (i.e., milk quantity of the first 305 days of lactation) ranged from 11,000 to 13,202 kg, with a bulk milk somatic cell count of 164,000 to 280,000 cells/mL. The cows received a total mixed ration (TMR) depending on their production level and were milked three times a day. All study animals were housed in free-stall barns with cubicles. The farms participated in a dairy herd improvement (DHI) program.
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Transcript profiling in the liver of early-lactating dairy cows fed conjugated linoleic acid

Transcript profiling in the liver of early-lactating dairy cows fed conjugated linoleic acid

In the present study, transcript profiling was carried out in liver biopsies from high-yielding dairy cows at week 5 of lactation in order to identify genes and pathways regulated by feeding rumen-protected conjugated linoleic acid (CLA) during the transition period. Analysis of a bovine whole genome microarray revealed a total number of 130 annotated differentially expressed genes (DEGs) in the liver between cows of the CLA group and the control group (filter: P b 0.05 and fold change (FC) ≥ 1.3 or ≤−1.3). The number of DEGs in the liver being up-regulated was markedly higher than that being down-regulated (86 vs. 44). Gene set enrichment analysis revealed that the most enriched biological processes and molecular functions assigned to the 86 up-regulated genes were S- methyltransferase activity, ribonucleoprotein complex biogenesis, homocysteine S-methyltransferase activity, methionine biosynthetic process and spliceosome assembly, while the most enriched biological processes and molecular functions assigned to the 44 down-regulated genes were exopeptidase activity, cytokinesis after mito- sis, cytokinesis during cell cycle, protein serine/threonine kinase activity and cytokinesis. The microarray dataset from this study has been deposited in NCBI's Gene Expression Omnibus under the accession number GSE87391 . © 2016 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ).
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Influence of estrus on rumination, activity, feed and water intake of dairy cows

Influence of estrus on rumination, activity, feed and water intake of dairy cows

The aim of this study was to investigate activity and rumination time (RT) measured by collar-mounted acceleration and microphone-based technology (HR-Tag monitoring system, SCR Engineers Ltd., Netanya, Israel) of dairy cows over the peri-estrus period. The data base consisted of 453 estrous cycles and cows, respectively. To ensure true estrus, only cows with AI leading to conception were included in the study. The reference period was defined as the mean of 3 d prior and 3 d post the day of estrus. With large intra- and inter-individual variation, activity and RT were significantly influenced by cows’ estrus. On the day of estrus, activity behavior was on average increased by 38.7%, whereas data of daily RT were on average reduced by 19.6% (83 min/d). The percentage of estrual cows with increased activity was 76.5%. In contrast, 86.2% of all cows showed decreased RT during estrus. Circadian rhythms of activity and RT were bimodal. Cows displaying estrus showed highest activity and lowest RT during the nocturnal and early morning hours between 0200 and 0800 h and 0400 and 1000 h on the day of estrus. Clear estrus-related deviations from base level were measured much earlier for RT than for activity. Activity behavior tended to be more pronounced in primiparous cows and high-yielding cows (440 kg/d) on the day of estrus compared with multiparous herd mates and cows with lower milk production (r40 kg/d). Rumination time was associated positively with parity and negatively with cows’ milk production on the day of estrus. During the reference period, RT was 384 min/d and 443 min/d for primiparous and multiparous (43 lacta- tions) cows and 445 min/d and 407 min/d for low- and high-yielding cows. Comprehen- sive knowledge of characteristics indicating estrus is important for improving estrus detection. Further research is recommended to investigate the potential benefit of combining data of activity and RT for practical application in daily herd management.
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Investigations on the effects of conjugated linoleic acids and dietary concentrate proportion on performance and various physiological parameters of periparturient dairy cows and their calves

Investigations on the effects of conjugated linoleic acids and dietary concentrate proportion on performance and various physiological parameters of periparturient dairy cows and their calves

been associated with a modified rumen fermentation pattern as indicated by an altered profile of short chain fatty acids. In addition, dietary supplemented CLA increased starch degradation and reduced rumen microbial protein synthesis (Pappritz et al. 2011). Consequently, CLA may influence rumen parameters like rumen pH (RpH) and rumen temperature (RT). An increased starch digestion may be led to a drop in RpH due to the fact that a rapid rumen fermentation raises the production of short chain fatty acids and further lactate (reviewed by Kafil et al. (2011)). Accordingly, RT may be increased because of the negative relationship between RpH and RT (AlZahal et al. 2008; Lohölter et al. 2013a) and a supposed higher rumen fermentation. In contrast to balance experiments and spot sampling of rumen fluid from cows fed at steady state, so-called rumen probes offer the opportunity for a continuous recording of both RpH and RT and can therefore provide useful additional information on the effects of CLA on general rumen fermentation in ad libitum-fed and free ranging dairy cows. Additionally, detailed data regarding the development of RpH and RT around calving under the influence of different feeding strategies during late pregnancy are less available. Moreover, there is a lack of information about the effect of parturition itself on RpH and RT. Hence, an experiment with dairy cows during the transition period was used to study the dynamics of RpH and RT via continuous measuring under the use of rumen probes. The experiment was previously described in detail by Petzold et al. (2013). The objective of this trial was to examine the influence of supplemented CLA on rumen parameters of cows fed low and high concentrate proportions in the diet antepartum (ap). For the present investigation a part of the animals of the four experimental groups were equipped with rumen probes, which enabled to study the effects of dietary concentrate feed proportion and CLA supplementation around parturition and the impact of parturition itself on RpH and RT. Compared with a adapted feeding, the rumen fermentation profile was supposed to be shifted towards a lowered RpH, eventually to a sub-acute rumen acidosis (SARA) and an elevated RT due to the high concentrate level. Moreover, it was hypothesized that CLA addition leads also in a drop of RpH and an increase in RT.
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