Impacts of self- and cross-sucking on cattle health and performance

Background: Improvement of dairy farms economics requires intensification, automatic milking, and artificial rearing methods. The ability to express normal behavior is one of the five freedoms to achieve animal welfare, whereas the display of abnormal behaviors is considered as an indicator of poor welfare. Cross-sucking is defined as sucking any body parts of pen-mate calves, whereas inter-sucking in cows is defined as sucking the udder or udder area. Previous studies showed that self- and cross-sucking during the calf-hood period could be a causal factor of milk sucking in adulthood. Aim: To investigate the effects of cross-sucking among calves and inter-sucking in cows on animal health status and performance. Materials and Methods: Gathering information from customized questionnaires, the study of the breeding records, recording of self- and cross-sucking behaviors, and health status of calves till weaning, and dairy cows before milking were performed in two governmental farms under the same managemental conditions in Sohag and Qena governorates. Results: Cross-sucking appeared in calves at the 2nd week of age followed by abscesses at ears and navels that were observed within cross-sucker calves. Milk sucking was higher in primiparous than multiparous cows during the second lactation period, as primiparous cows start to suck mostly around the 4th month of milking. Mastitis and elongation of the front teats were observed in sucker cows. Suffered animals had body condition scoring 3.5 or less. Interestingly, most of the cows displaying self-sucking were sucking another cow and were experienced self- or cross-sucking in their calf-hood. The use of pronged nose-rings was ineffective in preventing milk sucking and all cows were ultimately culled at the end of the season. Conclusion: The results of this study demonstrate the health problems of abnormal oral behaviors in terms of developed ears and navels abscesses in cross-sucker calves, and mastitis and teat deformities in milk-sucker cows. Furthermore, indexes that lead to oral satisfaction should be taken in priorities of farm managers to effectively reduce or prevent crosssucking in calves. Culling of cows and heifers suffering from sucking would be the ultimate uneconomic alternative in case of persistent suckers

Immunization with <i>Toxoplasma gondii</i> peroxiredoxin 1 induces protective immunity against toxoplasmosis in mice

<div><p>To develop a vaccine against <i>Toxoplasma gondii</i>, a vaccine antigen with immune-stimulating activity is required. In the present study, we investigated the immunogenicity and prophylactic potential of <i>T</i>. <i>gondii</i> peroxiredoxin 1 (TgPrx1). The TgPrx1 was detected in the ascitic fluid of mice 6 days postinfection, while specific antibody levels were low in the sera of chronically infected mice. Treatment of murine peritoneal macrophages with recombinant TgPrx1 triggered IL-12p40 and IL-6 production, but not IL-10 production. In response to TgPrx1, activation of NF-kB and IL-6 production were confirmed in mouse macrophage cell line (RAW 264.7). These results suggest the immune-stimulating potentials of TgPrx1. Immunization of mice with recombinant TgPrx1 stimulated specific antibody production (IgG1 and IgG2c). Moreover, spleen cell proliferation and interferon-gamma production significantly increased in the TgPrx1- sensitized cells from mice immunized with the same antigen. Immunization with TgPrx1 also increased mouse survival and decreased cerebral parasite burden against lethal <i>T</i>. <i>gondii</i> infection. Thus, our results suggest that TgPrx1 efficiently induces humoral and cellular immune responses and is useful as a new vaccine antigen against toxoplasmosis.</p></div

Survival of mice and parasite numbers in brains of surviving mice.

<p>(A) Six mice per group were immunized with TgPrx1-GST, GST, or PBS, and then challenged with 1 × 10³ tachyzoites of the <i>T</i>. <i>gondii</i> PLK strain. The survival rates (surviving mice/total mice) are calculated from three pooled independent experiments: PBS, 5/18 (27.8%); TgPrx1, 12/18 (66.7%); GST, 7/18 (38.9%). *, statistically significant differences in the survival rates at 30 days postinfection (dpi) were observed between the PBS-injected group and the recombinant-protein-immunized groups with a χ² test (<i>P</i> < 0.05). (B) Parasite numbers in the brains of the surviving mice at 30 dpi. Results are from three pooled independent experiments (PBS, n = 5; TgPrx1, n = 12; GST, n = 7). The results were analyzed with one-way ANOVA plus a Tukey–Kramer <i>post hoc</i> analysis, but there were no significant differences.</p

Effects of recombinant TgPrx1 on RAW cell lines.

<p>NF-kB/SEAP cells (A) and RAW 264.7 cells (B) were treated with 10 ng/mL LPS and recombinant TgPrx1-GST or GST protein for 48 h in the presence or absence of 20 μg/mL polymixin B to measure the SEAP and IL-6, respectively. Each value represents the mean ± standard deviation of quadruple samples. The different letters above the bars in the graphs indicate statistically significant differences among the test groups and the mock group (one-way ANOVA plus Tukey–Kramer <i>post hoc</i> analysis, <i>P</i> < 0.05).</p

Antigen and antibody levels of TgPrx1 in body fluids of infected mice.

<p>(A) C57BL/6 mice (n = 4) were intraperitoneally infected with 10³ <i>T</i>. <i>gondii</i> PLK or RH tachyzoites. TgPrx1 antigen was measured in ascitic fluid collected from experimentally infected mice at 0, 3, and 6 days postinfections (dpi). Each value represents the mean ± standard deviation of quadruplicate samples. nd, not detected. *, statistically significant differences were observed between the two groups with the Student’s <i>t</i> test (<i>P</i> < 0.05). <b>(B)</b> Production of IgG antibodies against TgPrx1 in chronically infected mice. C57BL/6 mice (n = 5) were intraperitoneally infected with 10³ <i>T</i>. <i>gondii</i> PLK tachyzoites. Serum samples were collected from the mice 4 weeks after infection and tested with indirect ELISAs, using recombinant TgPrx1-GST and TgGRA7 antigens. The mean optical density (OD) was determined at a wavelength of 415 nm. Each bar represents the mean ± standard deviation. Sera of uninfected mice (n = 4) were used as the negative control. *, statistically significant differences were observed between the uninfected and infected mice with the Student’s <i>t</i> test (<i>P</i> < 0.05).</p