Effects of Selective Dry Cow Treatment on Intramammary Infection Risk after Calving, Cure Risk during the Dry Period, and Antibiotic Use at Drying-Off: A Systematic Review and Meta-Analysis of Current Literature (2000–2021)

The objectives of this paper were (i) to perform a systematic review of the literature over the last 21 yr and (ii) to evaluate the efficacy of selective dry cow treatment (SDCT) vs. blanket dry cow treatment (BDCT) in dairy cows regarding the risk of intramammary infection (IMI) after calving, new IMI risk after calving, cure risk during the dry period, and a reduction in antibiotic use at drying-off by meta-analysis. The systematic search was carried out using the databases PubMed, CAB Direct, and ScienceDirect. A meta-analytical assessment was performed for each outcome of interest using random-effects models, and the relative risk (RR) for IMI and cure or the pooled proportion for antibiotic use was calculated. The final number of included studies was n = 3 for IMI risk after calving and n = 5 for new IMI risk after calving, cure risk during the dry period, and antibiotic use. The RR levels for IMI (RR, 95% confidence interval [CI]: 1.02, 0.94–1.11; p = 0.592), new IMI (RR, 95% CI: 1.06, 0.94–1.20; p = 0.994), and cure (RR, 95% CI: 1.00, 0.97–1.02; p = 0.661) did not differ significantly between SDCT and BDCT. Substantial heterogeneity was observed between the trials regarding the pooled proportion of antibiotic use within the SDCT groups (I2 = 97.7%; p < 0.001). This meta-analysis provides evidence that SDCT seems to be an adequate alternative to BDCT regarding udder health with a simultaneous reduction in antibiotic use. Limitations might arise because of the small number of studies included

Textile industry manufacturing by-products induce human melanoma cell proliferation via ERK1/2 activation

OBJECTIVES: Textiles used to make clothing can represent a source, often ignored, of chemicals potentially noxious to both skin and the whole organism. Among the most frequently produced potentially noxious chemical manufacturing by-products are formaldehyde (FA), nickel (Ni) and hexavalent chromium (Cr); they are of potential clinical interest as all are known to be carcinogenic to humans and to be potent skin sensitizers. The aim of this study was to investigate, in vitro, effects of these potentially dangerous compounds on two different melanoma cell lines. In particular, attention was focused on A375P, a poorly metastatic and low invasive cell line and SK-MEL-28, a highly metastatic cell line. MATERIALS AND METHODS: Effects of these compounds was evaluated on A375P and SK-MEL-28 cells. FA (1-5 7 10(-5) m), NiSO4 (10(-6) -10(-3) m), K2 Cr2 O7 (10(-7) -10(-6) m) effects on cell proliferation were evaluated by cell counting, while ERK pathway involvement was evaluated by Western blot analysis. RESULTS: Low concentrations of the chemicals, covering a range that corresponds to commonly accepted limits in textile production, induced a significant increase in cell proliferation concomitant with transient activation of phosphorylated ERK expression. CONCLUSIONS: Data obtained suggest that increasing attention must be focused on these by-products' potentially harmful effects in chemical manufacturing of clothes and accessories, that remain for long periods of time, in contact with human skin

Laying performance characteristics, egg quality, and integument condition of Saxonian chickens and German Langshan bantams in a free-range system

SUMMARY: Indigenous poultry breeds represent an important animal genetic resource. However, their characteristics in respect of performance, product quality, and integument condition are often poorly investigated. Therefore, the local breeds Saxonian chickens (SaChi) and German Langshan bantam chickens (GLB) of different plumage colors were characterized. The high-performing hybrid strain of Lohmann brown chickens (LB) served as the control group. For each group, 60 hens and 6 roosters were studied in an extensive free-range system from 21 to 80 wk of life. The plumage and foot pad quality were scored on 9 distinct observation dates and the measurements of the egg quality were performed at 7 different time periods.The number of eggs per hen housed in the first laying year was significantly lower in the SaChi (146.4 ± 30.8) and the GLB chickens (107.8 ± 20.4) when compared to the LB chickens (295.0 ± 16.8) (P < 0.001). Regarding laying performance, we detected effects of plumage color within both local breeds (P < 0.001). Within 4/7 plumage colors, effects of the breeder were also found (P ≤ 0.037). The eggs of the local chicken breeds showed lower egg weights (P < 0.001), shell breaking strength (P ≤ 0.041), albumen consistency (P < 0.001), and a lower egg shape index (P < 0.001), but higher proportions of yolk (P < 0.001) when compared to the eggs of the LB chickens. The logistic regression models for the plumage and footpad condition demonstrated that the SaChi and GLB hens underwent less plumage loss and footpad swelling than the LB hens (P < 0.001).Overall, this study shows that the laying performance of the local breeds was significantly lower, but there were noticeable advantages in terms of egg composition and animal welfare indicators when compared to a high-performing hybrid strain. In further studies and the use in extensive production systems, the observed performance differences between plumage colors and breeders should be taken into account

Flock-level risk factors of litter condition for the occurrence of plumage damage and skin lesions in commercial laying hen farms

ABSTRACT: Plumage damage (PD) as a result of severe feather pecking (SFP) and skin lesions (SL) due to cannibalism (CA) is serious welfare, performance, and economic problems in commercial layer farms. Genetics, nutrition, and housing conditions are central complexes that contribute to the multifactorial causes of these behavioral disorders. Practical recommendations consider the quality of litter as an important criterion for the prevention of SFP, although systematic longitudinal studies providing evidence-based findings are lacking.Therefore, the aim of this study was to investigate the effects of litter condition on the occurrence of PD and SL in the field using a longitudinal design. Integument scoring (PD and SL; 7 times), litter scoring (structure, cake formation, litter quality, and litter height; 12 times), and laboratory litter analysis (dry matter (DM), nitrogen (N), phosphorus (P) and pH value; 12 times) were performed in 28 laying hen flocks with a median flock size of 12,357 birds, in barn (n = 21) or free-range systems (n = 7), during the first laying period.Binary logistic regression (BLR) models showed the association of housing type and animal age on PD and SL (P < 0.001), and of the hybrid type on PD (P < 0.001). Furthermore, a significant association with PD and SL was observed for several litter traits. An increase in litter height, DM, and P was associated with lower PD (P ≤ 0.022) and SL (P < 0.001). In contrast, a higher N content of the litter was associated with an increase in SL (P = 0.007). Cake formation (P < 0.001) and a low structure (P = 0.025) of the litter showed an association with higher PD.In conclusion, this study identified caked litter with less structure, low height, and low contents of DM and P as risk factors for behavioral disorders in commercial laying flocks

Relation between Feed Particle Size Distribution and Plumage Condition in Laying Hens on Commercial Farms

Feather pecking is a serious problem in laying hen husbandry, which can lead to feather damage, performance losses and economic disadvantages. In this context, feed has been identified as an important factor, whereby scientific knowledge is primarily available on the effect of ingredients but hardly on the feed structure. In this study, feed samples from feather pecking and non-feather pecking herds from production farms were analyzed for their nutrient contents and feed particle sizes. More coarser (>2.00 mm) and fewer medium and finer feed particles (≤1.60 mm) were found in the feed of the flocks affected by feather pecking. The coarser components contained lower levels of nutrients important for preventing feather pecking (e.g., methionine, sodium). The study demonstrated that a feed structure that is too coarse can be considered a risk factor for feather pecking.Die Studie untersucht die Zusammensetzung der Futterpartikelfraktionen und deren Nährstoffgehalte in Legehennenfutter. Hierfür wurden 103 Futterproben von federpickenden (AH, n=37) und nicht-federpickenden Herden (CH, n=66) von Produktionsbetrieben mittels trockener Siebanalyse und Nährstoffanalytik untersucht. In den AH zeigten sich in der Futterstruktur im Vergleich zu den CH höhere Anteile an Partikeln >2,50 mm (MW ± STW: CH: 11,0 ± 8,5 %, AH: 24,9 ± 14,3 %) und 2,00-2,50 mm (CH: 11,2 ± 5,3 %, AH: 15,7 ± 5,7 %) bei niedrigeren Anteilen der Fraktionen 1,01-1,60 mm (CH: 22,9 ± 4,9 %, AH: 17,8 ± 5,7 %), 0,51-1,00 mm (CH: 25,5 ± 8,2 %, AH: 16,0 ± 6,8 %) und ≤0,50 mm (CH: 15,4 ± 5,0 %, AH: 11,0 ± 4,8 %) (p<0,001). Die Futter der AH (1470,8 ± 343,9 μm) wiesen dabei auch einen höheren geometrischen Durchmesser aus (GMD) im Vergleich zu den CH (1113,3 ± 225,7 μm) auf (p<0,001). Die vorgefundenen Anteile der Partikelgrößenfraktionen 1,01-1,60 mm und ≥2,50 mm lagen außerhalb des empfohlenen Referenzbereichs (p<0,001). Die Gehalte an Rohasche (CH: 130,3 ± 18,8 g/kg, AH: 115,9 ± 24,3 g/kg), Lysin (CH: 8,2 ± 1,0 g/kg, AH: 7,7 ± 1,2 g/kg), Methionin (CH: 3,4 ± 0,5 g/kg, AH: 3,2 ± 0,6 g/kg) und Natrium (CH: 1,7 ± 0,4 g/kg, AH: 1,3 ± 0,4 g/kg) waren bei den AH niedriger als in den CH (p≤0,041). Im Modell der logistischen Regression zeigten sich das Tieralter (p=0,041) und der GMD (p<0,001) als signifikante Einflussfaktoren auf das Auftreten von Federpicken. Anhand der Studie konnte gezeigt werden, dass eine zu grobe Futterstruktur als Risikofaktor für Federpicken zu betrachten ist

Edible Environmental Enrichments in Littered Housing Systems: Do Their Effects on Integument Condition Differ Between Commercial Laying Hen Strains?

The aim of this study was to investigate the effect of additional enrichment materials (EMs; pecking stones and alfalfa bales) on the occurrence of plumage damage, skin injuries, and toe injuries, with an emphasis on the possible differences between commercial hybrid strains of laying hens. During rearing (weeks 1–18, 16 compartments, 4000 pullets) and laying periods (weeks 21–72, 24 compartments, 2808 hens) in a littered housing system, EMs were permanently provided to the study groups (EXP), while control groups (CON) did not receive additional EM. In a two-factorial study design (two groups with four strains) with 351 hens per variant, the brown egg-laying Lohmann Brown classic (LB) and Bovans Brown (BB) strains as well as the white egg-laying Lohmann Selected Leghorn classic (LSL) and Dekalb White (DW) strains were investigated. Compared to the CON, the EXP showed reduced body mass during rearing (p < 0.001) and reduced albumen consistency in the laying period (p < 0.001). Regarding integument condition, the LSL in the EXP showed more toe injuries than in the CON (p = 0.018). Remarkably, genotype-environment interactions between strains and groups were evident (p < 0.001). In groups with an EM supply, plumage damage decreased in LB (p ≤ 0.033) and LSL (p ≤ 0.005) but increased in BB (p ≤ 0.003). Moreover, there were fewer skin injuries in LSL (p = 0.001) but more in BB (p = 0.001) in groups with access to EM. In view of the diverging effects between strains, future practical recommendations for laying hen husbandry should be strain-specific.:Introduction Materials and Methods Results Discussions Author Contributions Funding Acknowledgments Conflicts of Interest Reference

Edible Environmental Enrichments in Littered Housing Systems: Do Their Effects on Integument Condition Differ Between Commercial Laying Hen Strains?

The aim of this study was to investigate the effect of additional enrichment materials (EMs; pecking stones and alfalfa bales) on the occurrence of plumage damage, skin injuries, and toe injuries, with an emphasis on the possible differences between commercial hybrid strains of laying hens. During rearing (weeks 1&ndash;18, 16 compartments, 4000 pullets) and laying periods (weeks 21&ndash;72, 24 compartments, 2808 hens) in a littered housing system, EMs were permanently provided to the study groups (EXP), while control groups (CON) did not receive additional EM. In a two-factorial study design (two groups with four strains) with 351 hens per variant, the brown egg-laying Lohmann Brown classic (LB) and Bovans Brown (BB) strains as well as the white egg-laying Lohmann Selected Leghorn classic (LSL) and Dekalb White (DW) strains were investigated. Compared to the CON, the EXP showed reduced body mass during rearing (p &lt; 0.001) and reduced albumen consistency in the laying period (p &lt; 0.001). Regarding integument condition, the LSL in the EXP showed more toe injuries than in the CON (p = 0.018). Remarkably, genotype-environment interactions between strains and groups were evident (p &lt; 0.001). In groups with an EM supply, plumage damage decreased in LB (p &le; 0.033) and LSL (p &le; 0.005) but increased in BB (p &le; 0.003). Moreover, there were fewer skin injuries in LSL (p = 0.001) but more in BB (p = 0.001) in groups with access to EM. In view of the diverging effects between strains, future practical recommendations for laying hen husbandry should be strain-specific

Digital dermatitis in cattle: Treponemal immune modulation and immunological concepts of disease control

Dermatitis digitalis (DD) ist eine bakterielle Zehenhauterkrankung des Rindes, die weltweit für einen Großteil der Lahmheiten vor allem in der Milchviehhaltung verantwortlich ist und damit erhebliche wirtschaftliche Verluste und ein beeinträchtigtes Tierwohl bedingt. Hautläsionen betroffener Tiere sind neben vielen anderen anaeroben Keimen mit verschiedenen Treponema-Spezies besiedelt, die als primäre Krankheitserreger der DD gelten. Das infizierte Rind reagiert mit einer starken zellver- mittelten als auch humoralen Immunantwort, welche allerdings weder die Ausbildung klinischer Symptome noch eine erneute Infektion verhindern können. Obwohl in der Praxis einige Prophylaxemaßnahmen (Biosicherheitsmaßnahmen und desinfizierende Klauenbäder) etabliert wurden, ist es in den letzten Jahren trotz großer Bemühungen nicht gelungen, die Tiere effektiv vor einer Erkrankung zu schützen. Diese Übersichtsarbeit soll Ergebnisse aktueller Forschung über die Immunreaktion DD-erkrankter Tiere und sich daraus ergebende Kontrollstrategien darstellen. Außerdem wird auf derzeit im EU-Raum zur Verfügung stehende Möglichkeiten der Immunisierung eingegangen. Die hier vorgestellten immunologischen Konzepte stellen allerdings aufgrund wenig verfügbarer Literatur und fehlender Folgestudien lediglich die Ansätze des Wissens über immunologische Aspekte der DD dar, wobei Wissenslücken im Verständnis der Pathogenese aufgezeigt werden. Weitere Studien sind notwendig, um die komplexen Erreger-Wirt-Interaktionen und damit die Erkrankung besser zu verstehen. Schlüsselwörter: Lahmheit, Prophylaxe, Immunantwort, Vakzine, TP