Interactive classroom: from motoneuron activity to skeletal muscle contraction and relaxation.

Active learning and practices are strongly encouraged or made mandatory by local, national, and European organizations. Therefore, we set up an interactive practical classroom, engaging all of the attending students of the year (n = 47). Each student was assigned a physiological role (marked on a cardboard sign) in the following events: stimulation on motoneuron dendrites, sodium ions (Na+) influx and potassium ions (K+) efflux, action potentials onset and saltatory conduction along the axon, acetylcholine (ACh) neurotransmitter exocytosis following Ca2+ influx, ACh binding to postsynaptic membrane receptors, ACh-esterase action, excitatory postsynaptic potential, release of Ca2+ from the sarcoplasmic reticulum, mechanism of muscular contraction and relaxation, and rigor mortis. A sketch was drawn with colored chalks on the ground outside the room: the motoneuron with its dendrites, cell body, initial segment, myelinated axon, and synaptic bouton; the postsynaptic plasma membrane of the muscle fiber; and the sarcoplasmic reticulum. Students each had their own role and were asked to position themselves and move, accordingly. This resulted in a complete, dynamic, and fluid representation being performed. The evaluation of the effectiveness of the students' learning was limited at this pilot stage. However, positive feedback was received in the self-evaluation reports that were written by students on the physiological meaning of their own role, as well as in the satisfaction questionnaires requested by the University. The rate of students who successfully passed the written exam and the rate of correct answers that included the specific topics addressed in this practice were reported.NEW & NOTEWORTHY We set up an interactive practical classroom, engaging all the attending students of the year (n = 47). Each student was assigned a physiological role marked on a cardboard sign, starting from motoneuron stimulation up to skeletal muscle contraction and relaxation. Students were asked to actively reproduce physiological events, positioning themselves and moving around and onto drawings on the ground (motoneuron, synapsis, sarcoplasmic reticulum, etc.). Finally, a complete, dynamic, and fluid representation was performed.

FoxP3, CTLA-4, and IDO in Canine Melanocytic Tumors.

Despite promising immunotherapy strategies in human melanoma, there are few studies on the immune environment of canine melanocytic tumors. In humans, the activation of immunosuppressive cell subpopulations, such as regulatory T cells (Tregs) that express forkhead box protein P3 (FoxP3), the engagement of immunosuppressive surface receptors like cytotoxic T lymphocyte antigen (CTLA-4), and the secretion of molecules inhibiting lymphocyte activation, such as indoleamine-pyrrole 2,3-dioxygenase (IDO), are recognized as immunoescape mechanisms that allow tumor growth and progression. The aim of our study was to investigate the expression of these immunosuppression markers in canine melanocytic tumors and to postulate their possible role in melanoma biology and progression. Fifty-five formalin-fixed, paraffin-embedded canine melanocytic tumors (25 oral melanomas; 20 cutaneous melanomas; 10 cutaneous melanocytomas) were selected to investigate the expression of FoxP3, CTLA-4, and IDO by immunohistochemistry and RT-qPCR (real-time quantitative polymerase chain reaction). All of the tested markers showed high gene and protein expression in oral melanomas and were differently expressed in cutaneous melanomas when compared to their benign counterpart. IDO expression was associated with an increased hazard of death both in univariable and multivariable analyses (P < .05). FoxP3 protein expression >6.9 cells/HPF (high-power field) was an independent predictor of death (P < .05). CTLA-4 gene and protein expressions were associated with a worse prognosis, but only in the univariable analysis (P < .05). FoxP3, CTLA-4, and IDO likely play a role in canine melanoma immunoescape. Their expression, if supported by future studies, could represent a prognostic tool in canine melanoma and pave the way to future immunotherapeutic approaches in dogs.

When Pet Snacks Look Like Children's Toys! The Potential Role of Pet Snacks in Transmission of Bacterial Zoonotic Pathogens in the Household.

Recent foodborne pathogen outbreaks associated with dry pet food and treats have focused the attention on these products as vehicles of pathogens for both pets and their owners. This study investigates the purchasing habits of dog owners and determines if and in what form pet snacks can be potentially dangerous for humans, especially for children. For these purposes, questionnaires collected from 406 dog owners were evaluated and microbiological analyses were performed on 120 dry pet snacks. The shape of the pet snack affects the purchase (median score, Mdn = 6.4) and the star bone was the preferred one (Mdn = 7.1). Most of the participants (76.0%; p < 0.001) stated that snacks are attractive to their children and that the possibility for children to get in contact with pet snacks is rare, but not implausible (Mdn = 3.1). Indeed, more than 6% of respondents admitted that there had been incidents of involuntary ingestion of pet snacks, with fever and gastrointestinal manifestations. Microbiological analyses showed that 119 dry pet snacks analyzed of a total of 120 (99.2%) were in good sanitary condition except for one sample where the presence of Listeria ivanovii was confirmed. The upward trend in the presence of pets in households and the strong and continuous growth in value and volume of the pet food market led researchers to analyze possible public health issues. Children and infants in particular are the most exposed subjects as they are more likely to come into contact with pet snacks, attracted by a shape similar to that of a toy. For this reason, although our findings did not highlight important microbiological contamination of pet snacks, it would be useful to standardize food safety criteria with those for human food from a One Health perspective.

New animal-based measures to assess welfare in dromedary camels.

Reliable and measurable animal-based measures (ABMs) are essential for assessing animal welfare. This study aimed at proposing ABMs for dromedary camels identifying their possible associations with management. Data were collected at a permanent camel market; a total of 76 pens and 528 camels were evaluated. ABMs were collected for each welfare principle (i.e., good feeding, good housing, good health, appropriate behavior), while resources or management-based measures were collected at three levels of investigations (animal, herd, or caretakers). Associations were calculated by generalized linear models. Body condition score and thirst index (ABMs of good feeding) resulted negatively associated with short caretaker's experience, dirty bedding, limited shaded space, feeding and water space, and space allowance (P < 0.05). Resting behaviors and restricted movements (ABMs of good housing) were associated with short caretaker's experience, dirty bedding and water, rationed water distribution, water points in the sun, and presence of hobbles (P < 0.05). Disease, injury, and pain induced by management procedures (ABMs of good health) were negatively associated with short caretaker's experience, presence of hobbles, limited space allowance and shaded space, dirty bedding, and feeding and watering practices (e.g., frequency of distribution, resource quality, location of the troughs; P < 0.05). Response to approaching test and aggressivity (ABMs of Appropriate behavior) were negatively associated with limited space allowance, shaded, feeding and water space, and rationed water distribution (P < 0.05). Overall, the proposed ABMs seems to be appropriate indicators of welfare consequences in camels being able to identify factors related to housing and management practices that may impair or improve camel welfare.

E-Cadherin Expression in Canine Melanocytic Tumors: Histological, Immunohistochemical, and Survival Analysis.

E-cadherin, a glycoprotein involved in cell-cell adhesion, has a pivotal role in epithelial-mesenchymal transition, a process through which neoplastic epithelial cells develop an invasive phenotype. In human cutaneous melanomas, decreased E-cadherin expression is associated with shorter survival and increased Breslow thickness, whereas in the dog its role is poorly understood. Tumor thickness and modified Clark level were recently proposed as useful features to assess canine melanocytic tumors, but no studies investigated their association with E-cadherin expression. We performed immunohistochemistry on 77 formalin-fixed, paraffin-embedded primary canine melanocytic tumors. A 3-tier and a 2-tier classification system for assessing E-cadherin expression were tested, with the latter being more informative for the assessment of canine melanocytic tumors. E-cadherin expression was lower in cutaneous melanomas than melanocytomas, as well as in amelanotic tumors compared to pigmented tumors. In amelanotic melanomas, absent E-cadherin expression was associated with an unfavorable outcome, suggesting a potential use of this marker in defining the prognosis of amelanotic melanomas. E-cadherin expression was lower in tumors with greater tumor thickness and modified Clark level ≥IV, suggesting its possible utility in identifying the most invasive tumors. The expression of E-cadherin in oral melanomas was heterogeneous, but was associated with pigmentation and clinical outcome; thus, E-cadherin evaluation could be advantageous to detect the most aggressive neoplasms. However, cutaneous melanomas without E-cadherin expression frequently had a favorable clinical outcome. Hence, its importance as prognostic factor should be carefully considered depending on the tumor origin.

Serum concentrations of leptin in pregnant and non-pregnant bitches.

Leptin regulates body weight and several physiological processes including reproduction. We evaluated the circulating levels of leptin in pregnant and non-pregnant bitches as well as their correlation with body weight, food intake and number of foetuses. Nineteen healthy German shepherd bitches were used and divided in two groups (pregnant n = 12 and non-pregnant n = 7). Blood samples were collected every 15 days starting from ovulation (Day 0) throughout pregnancy (pregnant group, P) or throughout luteal phase (non-pregnant group, NP) In pregnant bitches, leptin concentrations increased from the day of ovulation (1.32 ± 0.06 ng/ml) up to day 45 (1.51 ± 0.06 ng/ml; p < .01) and returned to baseline values from day 60 post-ovulation. In non-pregnant bitches, leptin concentrations remained constant throughout the whole observation period (estimated marginal mean ± SE=1.33 ± 0.38 ng/ml). Pairwise comparisons showed significant differences between P and NP at day 45 post-ovulation (p < .05). Multivariable models indicated that, controlling for time and litter size, there was a positive relationship between leptin concentration and BW (p < .05) although Pearson coefficients showed that the correlation between BW and leptin was only significant in NP animals at day 45 (r = 0.76, p < .05). The multivariable approach also suggested that, holding BW and time constant, leptin concentrations tend to increase as the number of puppies increased (p = .06). Our study supports indirectly the contribution of the feto-placental unit to the circulating maternal leptin concentration.

Effect of aglepristone (RU534) administration during follicular phase on progesterone, estradiol-17ß and LH serum concentrations in bitches.

Aglepristone was administered in bitches during the follicular phase to evaluate its effects on progesterone, estradiol-17ß and LH serum concentrations. Ten German Shepherds were divided into two groups (treated n = 5; control n = 5). Treated bitches received 10 mg/kg BW of aglepristone subcutaneously during the early follicular phase, 24 hr after and then 7 days later. The control group was injected, at the same time periods, with saline solution (0.3 ml/kg BW). For the steroid evaluations, blood was collected daily from the onset of proestrus until the first day of cytological dioestrus. For LH base-line serum determination, blood was also collected every 20 min for 2 hr at the onset of proestrus. For LH surge identification, blood was collected daily (every 6 hr) starting from the day of the first administration of aglepristone or saline solution until the first day of dioestrus. All animals ovulated but the treated group presented longer ovulation-dioestrus intervals than the control group (5.2 ± 2.2 days p < .05). Serum concentrations of the evaluated hormones were similar between experimental animals except for serum LH. Indeed, no LH peaks were detected in the treated group while LH surges were clearly observed in the control group (9 ± 1 days after the beginning of proestrus. In particular, the area under the curve for LH was significantly lower in treated than control animals (12 ± 4 ng/ml x Day; p = .01). In conclusion, administrations of aglepristone during the follicular phase of the bitch does not affect the steroid hormone patterns but does prevent the occurrence of a LH surge. This work raises significant questions and opens perspectives concerning the mechanisms of ovulation in bitches.

Tumor Thickness and Modified Clark Level in Canine Cutaneous Melanocytic Tumors.

Breslow thickness and Clark level are prognostic factors for human cutaneous melanomas. Breslow thickness is measured with an ocular micrometer from the top of the granular layer of the epidermis to the deepest invasive cell across the broad base of the tumor, while Clark level is based on the anatomical level of invasion through the layers of the dermis. Because of the anatomical differences between humans and dogs, we evaluated the tumor thickness and a modified Clark level in 77 canine primary cutaneous melanocytic tumors. Tumor thickness (using both a traditional and a more convenient system) and modified Clark level were measured and associated with histological diagnosis and clinical outcome. Tumor thickness was a prognostic factor, being greater in animals with shorter overall survival and disease-free time. Cutoffs of 0.95 cm and 0.75 cm defined a higher hazard for an unfavorable outcome and to develop recurrence/metastasis, respectively. Because of an excellent agreement between the 2 methods, it was concluded that tumor thickness could be measured with a ruler when an ocular micrometer is not available. Modified Clark level was not found to be relevant for prognosis. However, we suggest that both tumor thickness and a modified Clark level can be valid additional parameters when histological diagnosis is uncertain. Further studies, including a wider sample population, would be worthwhile to confirm the prognostic significance of these 2 parameters.

FoxP3 and IDO in Canine Melanocytic Tumors.

Human melanoma is one of the deadliest forms of cancer, with poor prognosis and high resistance to chemotherapy and radiotherapy. The discovery of immunosuppressive mechanisms in the human melanoma microenvironment led to the use of new prognostic markers and to the development of immunotherapies targeting immune checkpoint molecules. Immunoescape mechanisms in canine melanoma have not yet been investigated, and no such immunotherapy has been tested. The aim of this study was to provide preliminary data on the expression of transcription factor forkhead box protein P3 (FoxP3) and indoleamine 2,3-dioxygenase (IDO) in primary canine melanocytic tumors and to investigate their prognostic role. Formalin-fixed, paraffin-embedded samples from 74 canine melanocytic tumors (26 oral melanomas, 23 cutaneous melanomas, and 25 cutaneous melanocytomas) were retrospectively evaluated by immunohistochemistry to explore the expression of FoxP3 and IDO. An increased risk of death due to melanoma was associated with a higher number of FoxP3+ cells per high-power field (FoxP3+/HPF), a higher percentage of CD3+ cells that were also FoxP3+ infiltrating and surrounding the tumor (%FoxP3), and a higher number of IDO+ cells/HPF (IDO+/HPF). A prognostic value for FoxP3 and IDO is suggested by our study, with optimal cutoffs of 14.7 FoxP3+ cells/HPF, 6.1 IDO+ cells/HPF, and 12.5% FoxP3+ cells. Both markers were also associated with tumor type. Multivariable analysis identified IDO+/HPF ( P < .001) as an independent prognostic marker. Even though stratification by diagnosis caused a loss of significance, results from the present study suggest a prognostic role for IDO and FoxP3, possibly related to the establishment of an immunosuppressive microenvironment.

Doppler evaluation of umbilical artery during normal gestation in sheep.

Throughout gestation, changes in foetal umbilical cord Doppler parameters in ewes were detected. Doppler ultrasonography of the umbilical artery was performed weekly starting at 18 weeks before parturition until birth. In the foetal umbilical artery (UA), systolic peak velocity (SPV), end diastolic velocity (EDV), increased (p for within-subjects effect <0.001) while pulsatility index (PI) resistance index (RI) decreased (p for within-subjects effect <0.001) with the progress of pregnancy. A linear trend was found on all patterns (p < 0.001). In particular, the EDV values increased significantly (p < 0.05) with respect to previous weeks, at weeks 16, 11, 10, 7, and 1 before parturition. The SPV values increased significantly (p < 0.05), with respect to previous observations, at weeks 11, 10, and 7 before parturition. Finally, the PI and RI decreased significantly (p < 0.05) only at week 7 before parturition. The increased velocities and reduced resistance index suggest a progressive increment in blood flow to the foetus towards the end of pregnancy. Foetal and utero-placental vascular parameters can be reliably evaluated using high-frequency ultrasound.

Correlation of two radioimmunoassay systems for measuring plasma pregnancy-associated glycoproteins concentrations during early pregnancy and postpartum periods in water buffalo.

This is the first time that PAG determination using two different antisera raised against PAG molecules purified from both caprine (RIA-706) and bubaline placentas (RIA-860) is reported in water buffalo. Ninety-eight buffalo cows, belonging to a buffalo herd subjected to a synchronization and artificial insemination (AI) programme, were enrolled in this study. Blood samples were taken on days 0 (AI), 23, 25, 28, 30 and 45. Pregnancy was confirmed by ultrasonography on days 28 and 45. The blood of 20 buffaloes that had calved was tested every five days from the day of calving until day 50 postcalving. Differences in PAG concentrations were observed between pregnant and nonpregnant buffaloes starting from day 23 post AI using both RIA-706 and RIA-860 (p < 0.001). However, estimated mean concentrations of PAG measured by RIA-706 were higher than RIA-860 (p < 0.001) and Bland-Altman analysis showed biases ranged from 0.0 ng/ml at day 23 to 0.79 ng/ml at day 28 post AI. Moreover, RIA-706 showed greater sensitivity and accuracy both at 23 and 25 days of pregnancy. RIA-706 and RIA-860 decreased below 1 ng/ml from 40 and 30 days postpartum, respectively, suggesting that PAG are better recognized by the antisera raised against the caprine PAG in the postpartum period also. This is essential when using PAG as an appropriate marker of early pregnancy after postpartum for detecting new pregnancies. The results of this study show that the ability of RIA systems to recognize early PAG could be improved using antisera raised against PAG molecules isolated from caprine placenta.

The first protocol for assessing the welfare of dromedary camels (Camelus dromedarius) kept under nomadic pastoralism.

There is no protocol to measure the welfare level of dromedary camels (Camelus dromedarious) kept under pastoralism-the predominant husbandry system of this species. This study therefore aimed to develop and describe a protocol for measuring welfare levels in dromedary camels kept under nomadic pastoralist conditions-. The indicators for each welfare principle (i.e., Good Feeding, Good Housing, Good Health, and Appropriate Behavior) were tailored to the specific conditions of camel pastoralism, drawing from the currently available protocol for assessing welfare in dromedary camels kept in intensive and semi-intensive systems. This adaptation was achieved using a structured literature search and Expert Knowledge Elicitation (EKE). The developed protocol, covering animal-, resource-, and management-based indicators, comprises two assessment levels: 'Caretaker-Herd level' and 'Animal level'. The Caretaker-Herd level is a face-to-face interview of about 10 min including 16 questions, spit into the four welfare principles, and a visual observation of applied animal handling practices. The 'Animal level' encompasses a behavioral observation and a visual clinical inspection of randomly selected individual dromedary camels, about 5 min/camel. The 'Animal level' includes 27 welfare indicators displayed for each welfare principle. The present study also includes the score for each indicator, the model for aggregating indicators' scores into compound indices for each welfare principle (PAI), and how to classify the herds based on the PAIs or to produce an overall welfare index for each herd. Even if the proposed protocol needs to be applied, refined, and validated, it is a first step toward a standardized method to collect data related to dromedary camel welfare kept under pastoralism. This framework may ultimately guide herd managers, animal health practitioners, experienced advisers, and lawmakers in fostering optimal conditions and proposing welfare standards for dromedary camels in pastoralist settings.

Interferon-Tau in Maternal Peripheral Blood and Its Relationship with Progesterone and Pregnancy-Associated Glycoproteins in the Early Phases of Gestation in Water Buffalo.

The aim of this study was to investigate the interferon tau (IFNt) concentration in the peripheral maternal blood during the early phase of pregnancy in buffalo cows and improve the knowledge on the physiological importance of circulating IFNt, evaluating the possible interaction with pregnancy-associated glycoproteins (PAGs) and progesterone (P4). Blood samples were taken from buffalo cows on day 0 (day of AI), 7, 14, 18, 28, and 40 post insemination for the IFNt, PAG, and P4 analysis and to determine the IFNt mRNA expression. The animals were categorized ex post into Pregnant, Non-pregnant and Embryo mortality groups. The interferon value was influenced by group (p = 0.003), being always higher in pregnant buffalo cows than in non-pregnant ones, while the embryo mortality group showed intermediate values between those for pregnant and non-pregnant animals. The mRNA expression of IFNt was not influenced by groups or any time points. The regression analysis that included IFNt as the independent variable showed that PAGs, from day 18 (p < 0.01), and P4, from day 28 (p < 0.05), were positively associated with IFNt values. The close associations among IFNt, PAGs and P4 demonstrate that all three molecules work together for fetal-placental well-being and pregnancy support. Unfortunately, the great individual variability in circulating IFNt makes this analysis unsuitable for early pregnancy diagnosis.

The Healthy Fatty Index Allows for Deeper Insights into the Lipid Composition of Foods of Animal Origin When Compared with the Atherogenic and Thrombogenicity Indexes.

The aim of this research was to validate the effectiveness of the Healthy Fatty Index (HFI) regarding some foods of animal origin (meat, processed, fish, milk products, and eggs) typical of the Western diet and to compare these results with two consolidated indices (atherogenic-AI, and thrombogenic-TI) in the characterization of the nutritional features of their lipids. The fatty acids profile (% of total fatty acids and mg/100 g) of 60 foods, grouped in six subclasses, was used. The AI, TI, and HFI indexes were calculated, and the intraclass correlation coefficients and the degree of agreement were evaluated using different statistical approaches. The results demonstrated that HFI, with respect to AI and TI, seems better able to consider the complexity of the fatty acid profile and the different fat contents. HFI and AI are the two most diverse indices, and they can provide different food classifications. AI and IT exhibit only a fair agreement in regards to food classification, confirming that such indexes are always to be considered indissolubly and never separately, in contrast to the HFI, which can stand alone.

Meat quality and sensory traits in rabbits fed with two different percentages of bovine colostrum.

The nutritional, antimicrobial, and antioxidant properties of bovine colostrum (BC) have encouraged its use in animal nutrition as a functional food in recent years. Nonetheless, the potential implications of BC supplementation on meat quality remain to be thoroughly assessed. To address this, thirty-nine New Zealand White rabbits (n = 13/group) were fed different dietary regimens until slaughter.: commercial standard diet for the control group (C) and C with 2.5% and 5% w/w of BC for BC-2.5 and BC-5 groups, respectively. Rabbits were slaughtered at 91 days of age and meat quality, and sensory characteristics were evaluated at days 2 (48 h after slaughter), 5, and 10 of refrigerated storage at 4 °C. The addition of colostrum in the diet resulted in a reduction of the total viable count, albeit only at the highest concentration and at the final detection, whereas for Lactobacillus spp. and Pseudomonas spp., there was little or no effect. The colour coordinates showed no differences between the groups, but they varied over time according to diet. Some differences between groups emerged in the definition of sensory attributes but did not affect the overall liking and overall scores of individual descriptors. These results indicate that the use of colostrum in rabbit feeding does not significantly impart meat quality and sensory attributes, but the potential of this valuable by-product for the food industry needs further investigation.

Bovine Colostrum Supplementation in Rabbit Diet Modulates Gene Expression of Cytokines, Gut-Vascular Barrier, and Red-Ox-Related Molecules in the Gut Wall.

Rabbits, pivotal in the EU as livestock, pets, and experimental animals, face bacterial infection challenges, prompting a quest for alternatives to curb antibiotic resistance. Bovine colostrum (BC), rich in immunoregulatory compounds, antimicrobial peptides, and growth factors, is explored for disease treatment and prevention. This study assesses BC diet supplementation effects on rabbit intestines, examining gene expression. Thirty female New Zealand White rabbits at weaning (35 days) were divided into three experimental groups: control (commercial feed), 2.5% BC, and 5% BC. The diets were administered until slaughtering (81 days). BC-upregulated genes in the jejunum included IL-8, TGF-ß, and CTNN-ß1 at 5% BC, while PLVAP at 2.5% BC. Antioxidant-related genes (SOD1, GSR) were downregulated in the cecum and colon with 2.5% BC. BC 5% promoted IL-8 in the jejunum, fostering inflammation and immune cell migration. It also induced genes regulating inflammatory responses (TGF-ß) and gastrointestinal permeability (CTNN-ß1). BC 5% enhanced antioxidant activity in the cecum and colon, but no significant impact on anti-myxo antibody production was observed. These results suggest that BC has significant effects on the rabbit gastrointestinal tract's inflammatory and antioxidant response, but further research is required to fully understand its histological and physiological impact.

The Link between the Perception of Animal Welfare and the Emotional Response to Pictures of Farm Animals Kept in Intensive and Extensive Husbandry Systems: An Italian Survey.

As livestock production grows to satisfy the global demand for animal products, understanding public attitudes towards different husbandry systems becomes essential for both animal welfare and socio-economic reasons. This study aimed to investigate people's emotional responses toward pictures of farm animals kept in intensive and extensive husbandry systems, their perception of animal welfare, and their choices as animal product consumers. A questionnaire that included demographic questions and photos of cows, pigs, chickens, and rabbits in both intensive and extensive systems was distributed electronically and physically and completed by 835 respondents. Photos of animals in intensive systems elicited more negative emotions, especially for pigs and rabbits (p < 0.05), as opposed to extensive systems, which elicited more positive emotions, especially for chickens (p < 0.001). Higher welfare levels were perceived for extensively farmed animals (p < 0.001) and for cattle compared to all other species, regardless of the husbandry system (p < 0.001). The quality of the emotional response was positively associated with welfare perception (p < 0.001) and negatively associated with the importance given to welfare when purchasing animal products (p < 0.001). Finally, the emotional response was found to be affected by gender, education, household composition, living area, pet ownership, and eating habits. The implications and limitations of these findings are discussed.

Crossbreeding to improve local chicken breeds: predicting growth performance of the crosses using the Gompertz model and estimated heterosis.

The present study aims to validate the Gompertz model to predict the growth performance of chicken crosses according to growth curve parameters of the parental lines and the estimated heterosis for each curve parameter. A total of 252 one-day-old chicks of both sexes belonging to 6 genotypes, including Ross 308, Sassò (SA), Bionda Piemontese (BP), and Robusta Maculata (RM), and the crosses between these local breeds and SA (BP × SA and RM × SA) were randomly allocated in 18 pens (3 pens/genotype) in mixed-sex groups (14 animals/pen; 7 females and 7 males). The individual body weight (BW) of all birds was recorded once a week from hatching until slaughtering (81 d for Ross 308; 112 d for SA, 140 d for the other genotypes). We drew up our final dataset with 240 birds (40 birds/genotype; 20 females and 20 males). The growth curve of each genotype was described using the Gompertz model, and the heterosis for each growth curve parameter was calculated as the difference between F1 crosses and the average of parental breeds. The predicted growth curve parameters were evaluated by cross-validation. The Gompertz model accurately estimated the growth curves of all the genotypes (R2 > 0.90). Heterosis was significant for almost all growth curve parameters in both crosses (P < 0.05). Heterosis ranged from -13.0 to +11.5%, depending on parameters, but varied slightly between the crossbreeds (BP × SA and RM × SA). The predicted values of adult BW, weight at the inflection point, and maximum growth rate were overestimated for BP × SA and underestimated for RM × SA, with a mean error between observed and predicted values <│2.7│% for all the curve parameters. In conclusion, the growth performance of chicken crosses between local breeds and commercial strains can be accurately predicted with Gompertz parameters of the parental lines adjusting for heterosis.

New approaches to selecting a scan-sampling method for chicken behavioral observations and their practical implications.

The use of the scan-sampling method, especially when a large amount of data is collected, has become widespread in behavioral studies. However, there are no specific guidelines regarding the choice of the sampling interval in different conditions. Thus, establishing a standard approach for video analysis represents an important step forward within the scientific community. In the present work, we hypothesized that the length of the sampling interval could influence the results of chicken behavioral study, for which we evaluated the reliability, accuracy, and validity of three different sampling intervals (10, 15 and 30 min). The Bland-Altman test was proposed as an innovative approach to compare sampling intervals and support researcher choices. Moreover, these sampling intervals were applied to compare the behavior of 4 chicken genotypes kept under free-range conditions. The Bland-Altman plots suggested that sampling intervals greater than 10 min lead to biases in the estimation of rare behaviors, such as "Attacking". In contrast, the 30-min sampling interval was able to detect differences among genotypes in high-occurrence behaviors, such as those associated with locomotory activity. Thus, from a practical viewpoint, when a broad characterization of chicken genotypes is required, the 30-min scan-sampling interval might be suggested as a good compromise between resources and results.

Colostrum Quality in Different Goat Breeds Reared in Northern Italy.

This study aimed to characterize the colostrum quality in three different local goat breeds of Northern Italy (i.e., Frisa Valtellinese, Orobica, and Lariana) and a cosmopolitan one (i.e., Camosciata delle Alpi) (n = 30 per breed), reared under traditional semi-extensive and intensive systems, respectively. Lariana showed the highest percentage of fat (10.18 ± 3.14%) and total solids (30.73 ± 4.89%) but the lowest percentage of lactose (1.87 ± 0.82%; p < 0.05); Orobica had the lowest percentage of fat (7.13 ± 2.48%), total solids (24.11 ± 5.48%), and protein (10.77 ± 4.53%) but the highest percentage of lactose (3.16 ± 0.73%; p < 0.05). This suggests that breeds which have a more pronounced meat aptitude (i.e., Frisa and Lariana) have a higher concentration of components than breeds with more dairy aptitude (i.e., Orobica and Camosciata). Uni- and multivariate analyses showed that IgG is the parameter that best differentiates local breeds from cosmopolitan ones (p < 0.01). Colostrum from Frisa goats showed the highest IgG concentration (100.90 ± 8.11 mg/mL), while the lowest concentration was in the Camosciata breed (74.75 ± 20.16 mg/mL). Finally, the highest lactoferrin concentration was in Frisa (1781.3 ± 892.6 µg/mL) and the lowest in Camosciata and Lariana (763.1 ± 357.9 and 1148.0 ± 858.6 µg/mL, respectively; p < 0.05). Differences between Camosciata and local breeds could be due to the different farming systems, in addition to the genetic characteristics. The higher quality of colostrum produced by some local goats could be an adaptive characteristic that helps the growth and survival of the kids.