Intestinal health of squab pigeons responded to parental dietary protein levels during breeding period.

The objective of this study was to determine the effects of dietary crude protein (CP) levels on intestinal antioxidant status, tight junction proteins expression, and amino acids transporters levels in squabs. A total of 180 pairs of White King parent pigeons approximately 10 mo old were randomly assigned to 5 groups with 6 replications of 6 pairs of parental pigeons each, and were fed with 14, 15, 16, 17, and 18% CP diets for 46 d, respectively. Dietary increasing CP levels increased final body weight (linear and quadratic, P < 0.05), serum urea nitrogen (linear, P<0.05) and triglyceride levels (quadratic, P < 0.05), and reduced kidney relative weight (quadratic, P < 0.05) in squabs. Final body weight of squabs in the 18% CP diet group was higher than that of the 14, 15, and 16% CP diet groups (P < 0.05) but was similar to that of the 17% CP diet group (P > 0.05). Increasing dietary CP levels reduced intestinal malondialdehyde contents (linear and quadratic, P < 0.05) and jejunal total superoxide dismutase (T-SOD) activity (linear, P < 0.05), and enhanced (linear and quadratic, P<0.05) ileal catalase and T-SOD activities in squabs, and these effects were more prominent in the 17% CP diet group. Graded CP levels up-regulated the mRNA expression of intestinal zonula occludens 1 (linear, P < 0.05), solute carrier family 7 members 9 (linear, P < 0.05) and claudin 1 (CLDN1, linear and quadratic, P < 0.05), ileal CLDN3 and solute carrier family 6 members 14 (linear, P < 0.05) but lowered jejunal solute carrier family 6 member 14 (quadratic, P<0.05) mRNA expression in squabs. The effects of dietary CP levels on intestinal tight junction proteins expression were more apparent when its supplemental levels were 18%. These results suggested that increasing parental dietary CP levels ranged from 14 to 18% during breeding period improved growth and intestinal function of squabs, with its recommended level being 17%.

Effects of granular feed on reproductive metabolism of breeding pigeons, intestinal development and microbiota of squab pigeons-A double-edged sword.

Pigeons like to eat raw grains, but meat pigeon enterprises often use compound feeds instead of raw grains to feed breeding pigeons to increase economic efficiency, which may change the pigeon's dietary behavior, and consequently lead to health and welfare problems. The purpose of this study was to investigate the effect of granular feeds on the health of high-yielding breeding pigeons and squabs in lactation. The results showed that, compared with raw grain group, the provision of granular feed resulted in lower total feed intake without affecting the weight of lactating breeding pigeons. Meanwhile, reproductive metabolism was improved and no oxidative stress was observed, which indicated that granular feeds had a positive effect on breeding pigeon's health. However, granular feed adversely affected jejunum development in squabs, compare wtih raw grain group, the growth rate of squab was reduced. Sequencing of the 16 s rRNA gene revealed that granular feed induced intestinal microbiota dysbiosis in the squabs. The use of granular feed reduced the relative abundance of gut microorganisms in functional categories related to lipid and energy metabolism, resulting in a decrease in the relative abundance of beneficial bacteria such as Bifidobacterium, Ligilactobacillus, Atopobium, and an increase in that of inflammation-related Limosilactobacillus, which likely inhibited squab intestinal development and growth. Although the use of granular feed can improve breeder metabolism, it affect the composition of the microbial community and gut development of squabs. Therefore, the use of granular feed in production should be more careful to avoid causing growth obstruction of squab.

Linoleic acid ameliorates intestinal mucosal barrier injury in early weaned pigeon squabs (Columba livia).

The study aimed to investigate whether linoleic acid could improve the intestinal barrier function of squabs under weaning stress conditions. Totally 320 7-d-old weaned squabs were randomly divided into four treatment groups, including control group (CON), 0.7% linoleic acid addition group (LA007), 1.4% linoleic acid addition group (LA014) and 2.1% linoleic acid addition group (LA021). At 21 d, eight squabs were randomly selected from each treatment group for sampling and determination. The results showed that adding linoleic acid could improve (P < 0.05) the body weight of weaned squabs, and LA014 had the best effect. With the increase of linoleic acid dosage, villi height and villi area increased linearly or quadratically (P < 0.05), and reached the maximum in LA021 or LA014, respectively. The linoleic acid supplementation could improve the intestinal tight junction of weaned squabs, and the LA014 was the most significant (P < 0.05). With the linoleic acid increasing, the levels of intestinal IL-6 and TNF-α decreased linearly (P < 0.05), while intestinal IL-10 increased quadratically (P < 0.05) and reached the maximum in LA014. Serum endotoxin and diamine oxidase levels decreased linearly (P < 0.05) and reached the lowest level in LA014. The ultrastructure of villi revealed that the length of ileal microvilli in LA014 was significantly increased (P < 0.05) and the microvilli became dense, and the mitochondria in epithelial cells returned to normal state. Further exploring the mechanism of linoleic acid alleviating intestinal injury caused by weaning stress in squabs, it was found that linoleic acid down-regulated (P < 0.05) the relative protein expression of TLR4, MyD88, phosphorylated JNK, and phosphorylated p38, reducing secretion of pro-inflammatory factors IL-6 and TNF-α. This study indicated that linoleic acid could alleviate intestinal barrier injury of early weaned squabs by down-regulating TLR4-MyD88-JNK/p38-IL6/TNF-α pathway.

Artificial feeding of early weaned squabs can reduce the burden of breeding pigeons and shorten the breeding cycle. However, similar to early weaned mammals, early weaned squabs would also inevitably undergo severe physiological and psychological stress responses in the early stage. The growth performance and immunity of early weaned squabs were inferior to those of the parent feeding squabs. Previous studies suggest that linoleic acid played an important role in the growth and development of squabs. Therefore, the study aimed to investigate whether linoleic acid could improve the intestinal barrier function of squabs under weaning stress conditions. Totally 320 7-d-old weaned squabs were randomly divided into four treatment groups, including control group and linoleic acid addition groups with three different doses. At 21 d, eight squabs were randomly selected from each treatment group for sampling and determination. The results indicated that under weaning stress conditions, linoleic acid could weaken the inflammatory response, and alleviate the intestinal epithelial barrier damage of weaned squabs, specifically by promoting the development of intestinal villi, strengthening the tight junction, reducing intestinal permeability, and promoting the secretion of anti-inflammatory factors.

Chemical composition of pigeon crop milk and factors affecting its production: a review.

Pigeons are important commercial poultry in addition to being ornamental birds. In 2021, more than 111 million pairs of breeding pigeons were kept in stock and 1.6 billion squabs were slaughtered for meat in China. However, in many countries, pigeons are not domestic birds; thus, it is necessary to elucidate the factors involved in their growth and feeding strategy due to their economic importance. Pigeons are altricial birds, so feedstuffs cannot be digested by squabs, which instead are fed a mediator named pigeon crop milk. During lactation, breeding pigeons (both female and male) ingest diets and generate crop milk to feed squabs. Thus, research on squab growth is more complex than that on chicken and other poultry. To date, research on the measurement of crop milk composition and estimation of the factors affecting its production has not ceased, and these results are worth reviewing to guide production. Moreover, some studies have focused on the formation mechanism of crop milk, reporting that the synthesis of crop milk is controlled by prolactin and insulin-activated pathways. Furthermore, the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) pathway, target of rapamycin (TOR) pathway and AMP-activated protein kinase (AMPK) pathway were also reported to be involved in crop milk synthesis. Therefore, this review focuses on the chemical composition of pigeon crop milk and factors affecting its production during lactation. This work explores novel mechanisms and provides a theoretical reference for improving production in the pigeon industry, including for racing, ornamental purposes, and production of meat products.

Application potential of chicken DNA chip in domestic pigeon species - Preliminary results.

Introducing the SNP technology to pigeon breeding will enhance the competitiveness of a sector that produces one of the healthiest and best quality meats. The present study aimed to test the applicability of the Illumina Chicken_50K_CobbCons array on 24 domestic pigeon individuals from the Mirthys hybrids and Racing pigeon breeds. A total of 53,313 SNPs were genotyped. Principal component analysis shows a significant overlap between the two groups. The chip performed poorly in this data set, with a call rate per sample of 0.474 (49%). The low call rate was likely due to an increase in the evolutionary distance. A total of 356 SNPs were retained after a relatively strict quality control. We have demonstrated that it is technically feasible to use a chicken microarray chip on pigeon samples. Presumably, with a larger sample size and by assigning phenotypic data, efficiency would be improved, allowing more thorough analyses, such as genome-wide association studies.

Shelf life extension of minced squab using poly-lactic acid films containing Cinnamomum verum essential oil.

The effects of poly-lactic acid films containing different concentrations of Cinnamomum verum essential oil (CVEO) on microbial, chemical and sensory criteria of minced squab were assessed during the storage at 4 °C for 12 days. The counts of total aerobic bacteria, psychrotrophic bacteria, lactic acid bacteria, pseudomonads and Enterobacteriacea of wrapped samples with PLA films containing 0.6 and 0.9 % CVEO never reached 7 log CFU/g during the storage. Counts of E. coli and L. monocytogenes spiked to the PLA-wrapped with 0.6 or 0.9 CVEO squab samples were an order and 2 orders of magnitude lower, respectively, after the storage comparing to control. Also, samples wrapped with PLA films containing different concentrations of CVEO had lower total volatile base nitrogen, and thiobarbituric acid reactive substances values vs. control. Finally, applying of PLA films containing different concentration of CVEO, led to minor changes in sensory characteristics (P > 0.05).

Early Weaning Stress Induces Intestinal Microbiota Disturbance, Mucosal Barrier Dysfunction and Inflammation Response Activation in Pigeon Squabs.

Early weaning stress has been reported to impair intestinal health in mammals. Like mammals, weaning of the pigeon squab, an altricial bird, is associated with social, environmental and dietary stress. However, understanding of weaning stress on intestinal functions is very limited in altricial birds, especially in squabs. This study was aimed to evaluate the effects of early weaning stress on intestinal microbiota diversity, architecture, permeability, the first line defense mechanisms, mucosal barrier functions, and immune cell responses. A total of 192 newly hatched squabs were randomly allocated into two groups, one weaned on day 7 and the other remained with the parent pigeons. Mucosal tissue and digesta in ileum, as well as blood samples, were collected from squabs (n = 8) on days 1, 4, 7, 10, and 14 postweaning. Our results showed that weaning stress induced immediate and long-term deleterious effects on both growth performance and intestinal barrier functions of squabs. Early weaning significantly increased ileal bacterial diversity and alters the relative abundance of several bacteria taxa. Weaning stress can also cause morphological and functional changes in ileum, including an atrophy in villi, an increase in permeability, and a variation in the mRNA expression of genes encoding mucins, immunoglobulins, tight junction proteins, toll-like receptors, and cytokines, as well as the concentration of secretory IgA. We concluded that the impaired intestinal barrier functions accompanied with early weaning stress seems to be the main reason for the poor growth rate after weaning in squabs. In addition, the disturbance of intestinal microbiota of early weaning stress in squabs coincided with dysfunction of intestinal mucosal barrier and activation of inflammation cell responses that were possibly mediated via the activation of toll-like receptors.

Effects of Coated Sodium Butyrate and Polysaccharides From Cordyceps cicadae on Intestinal Tissue Morphology and Ileal Microbiome of Squabs.

This experiment was conducted to investigate the effects of dietary supplementation with different levels of coated sodium butyrate (CSB) and polysaccharides extracted from Cordyceps cicadae (CCP) on growth performance, intestinal tissue morphology and ileum microbiome in squabs. A total of 420 1-day-old squabs were randomly divided into seven groups with 5 replicates each and 12 squabs per replicate. The squabs were fed basal diet (control group) and basal diet supplemented with different levels of CSB (275, 550, and 1,100 mg/kg, groups CSB-275, CSB-550, CSB-1100) and CCP (27.5, 55, and 110 mg/kg, groups CCP-27.5, CCP-55, and CCP-110), respectively. The experiment was conducted for 28 days. The results revealed that the final BW and average daily gain concentration were higher (P < 0.05) in squabs of CSB-275 and CCP-110 groups than those in the CON group. Comparing with control group, the squabs in the groups CSB-275, CSB-550, and CCP-55 obtained higher villus height/crypt depth (VH/CD) of the duodenum and higher VH of the jejunum (P < 0.05). Operational taxonomic units in the groups CSB-550 and CCP-27.5 were also increased (P < 0.05). Regarding the relative abundance of flora, the Actinobacteria abundance in the groups CSB-550, CSB-1100, and CCP-55 were higher than in control group (P < 0.05), and the Aeriscardovia abundance of CSB-275, CSB-550, CSB-1100, and CCP-110 were elevated (P < 0.05). However, the Enterococcus abundance in CSB-275, CSB-550, CSB-1100, and CCP-27.5 decreased (P < 0.05). In summary, results obtained in the present study indicate that CSB and CCP can improve growth performance, intestinal microbial balance and gut health of squabs.

Influence of dietary phosphorus concentrations on the performance of rearing pigeons (Columba livia), and bone properties of squabs.

The objective of this study was to investigate the effects of dietary P levels on the performance of rearing pigeons, and bone characteristics of squabs from 7 to 21 d of age. A total of 192 pairs of adult Silver King pigeons (40 wk of age) were used. The pigeons were randomly allocated to one of 4 treatment groups, each consisting of eight replicates of 6 pigeon pairs per replicate. Dietary treatments included the basal diet (containing 0.3% of P), the basal diet supplemented with 0.2, 0.4, or 0.8% inorganic P. And the dietary Ca content was kept at 1.40% across all treatments. The experimental diets were fed to parent pigeons as corn-soybean complete pellet feed, and squabs fed with crop milk secreted by parent pigeons. Pigeons in the group of 0.4% supplemental non-phytate phosphorus (NPP) had shorter (P = 0.045) oviposition interval than those in the control group and group of 0.8% NPP. When the diet was supplemented with 0.8% of NPP, the least average egg weight was observed (P = 0.006). Female breeding birds had much higher (P < 0.01) Ca, P, and ALP in serum than male ones. At 7-d of age, dietary P supplementation influenced P and Ca content in tibia ash of squabs (P < 0.05). The tibia ash Ca content in the group of 0.2% NPP was the highest among the treatments (P = 0.007). At d 21 of age, both the birds in the group of 0.4 and 0.8% NPP had higher tibia breaking strength (P < 0.01) and tibia ash contents (P < 0.001) compared to the ones in the control group. In conclusion, the P deficiency in the diet of parent pigeons could cause poor bone mineralization of squabs, especially impaired the bone-breaking strength and bone ash content. The 0.8% of NPP supplementation in the diet has a positive influence on mineralization of squabs although production depression was observed. Both P and Ca metabolism of female breeding birds were more active than male ones at earlier time points of rearing period. The desirable supplemental NPP level in diet for breeding pigeon was 0.4% according to the performance data in the present trial. The recommended Ca: P ratio for pigeons, which was different from the optimum value for broilers, needs to be studied in the future.

Research Note: Morphology and immune function development of the jejunum and ileum in squab pigeons (Columba livia).

The study was aimed to evaluate the morphology and immune function development of the jejunum and ileum in squab pigeons (Columba livia), by determining the villus ultrastructure, secretory IgA, and cytokines. Eight squabs were randomly selected and sampled on the day of hatch (DOH), d 7 (D 7), 14 (D 14), and 21 (D 21) post-hatch, respectively. The results showed that under transmission electron microscope, the enterocyte circumference in jejunum and ileum decreased with age. The tight junction involved in enterocyte circumference of jejunal villi plateaued from D 7, whereas that of ileal villi changed irregularly. The microvilli of jejunal and ileal villi was maximum at D 14. Under scanning electron microscope, the villus morphology of jejunum and ileum appeared finger-shaped at DOH. After D 7, the jejunal villi were still finger-shaped whereas the ileal villi were leaflike. The secretory IgA in jejunum was significantly increased at D 21. The TGF-ß decreased linearly in jejunum and ileum. The anti-inflammatory cytokines increased linearly and proinflammatory cytokines decreased linearly in jejunum and ileum with age. In conclusion, the morphological changes of jejunal epithelium were concentrated at DOH-D 7 and ileal epithelium at DOH-D 14 mainly. The changes in mucus layer and immune-related factors of jejunum and ileum persisted for almost the entire period.

Comparative morphological study of the oropharyngeal floor of squabs and adult domestic pigeons (Columba livia domestica).

The current study compared the morphological features of the oropharyngeal floor of squabs and adult domestic pigeons (Columba livia domestica). Samples from the oropharyngeal floor of both squabs and adult pigeons were collected directly after slaughtering. The collected samples were examined grossly, morphometrically, and by scanning electron microscopy (SEM). The lower beak had triangular shape with pointed rostral end. The tongue did not fill the entire oral floor in squabs as well as adult pigeons. The lingual apex of squabs had a small lingual nail while that of the adult pigeons had a well-developed lingual nail. The lingual body was separated from the lingual root by a transverse papillary crest, which was "V" shaped in squabs but "U"-shaped in adult pigeons. Filiform papillae were distributed on the dorsal surface of lingual apex, as well as, body, but were absent on the root. The lingual root presented fine elevations and low projections in squabs and adult pigeons, respectively. On the other hand, the tongue of adult pigeons had larger number of the lingual salivary glands openings compared to that of squabs. In addition, the edges of the glottis had numerous small projections in squabs bur presented large dome-shaped papillae in adult pigeons. Moreover, adult pigeons had longer pharyngeal papillae at pharyngoesophageal junction than those of squabs. In conclusion, these variations suggest that adult pigeons adapted well to their diet, which might reflect higher efficiency of food prehension.

Targeted disruption of TORC1 retards young squab growth by inhibiting the synthesis of crop milk protein in breeding pigeon (Columba livia).

This study was conducted to explore the regulatory role of the target of rapamycin complex 1 (TORC1) signaling pathway in crop milk synthesis in breeding pigeons (Columba livia). Three groups of breeding pigeons in the lactation period (n = 30 pairs/group) were respectively injected with rapamycin (RAPA, a specific inhibitor of the target of rapamycin complex) at doses of 0 (vehicle, control), 0.6, or 1.2 mg/kg body weight (BW)/day via the wing vein for 7 days. The average daily feed intake (ADFI) and BW of the breeding pigeons and the BW of young squabs were respectively recorded throughout the experimental period. The breeding pigeons were sacrificed to collect their crop tissues, crop milk, and serum on the eighth day of the experiment. The results showed that neither 0.6 nor 1.2 mg/kg BW RAPA injection affected BW loss or ADFI in breeding pigeons (P > 0.05), while crop thickness and crop relative weight were significantly decreased (P < 0.05) in the 1.2 mg/kg BW rapamycin-injected group. Simultaneously, RAPA (especially at 1.2 mg/kg BW) decreased the crude protein, αs1-casein, αs2-casein, ß-casein, and amino acid contents (Asp, Thr, Ser, Glu, Gly, Ala, Cys, Val, Met, Ile, Leu, Tyr, Lys, His, Arg, and Pro) of crop milk (P < 0.05) and the concentrations of albumin, total protein, and uric acid in the serum of breeding pigeons (P < 0.05). Additionally, the expression of TORC1 pathway-related proteins (TORC1, S6K1, S6, 4EBP1, and eIF4E) was downregulated in the crop tissues of breeding pigeons by 0.6 or 1.2 mg/kg BW/day RAPA injection (P < 0.05). Accordingly, the average daily gain (ADG) of young squabs declined, and the mortality rate increased significantly (P < 0.05). Together, the results showed that RAPA reduced protein and amino acid levels in the crop milk of breeding pigeons and retarded young squab growth, suggesting a crucial role of TORC1 in crop milk synthesis in breeding pigeons.

Leucine promotes the growth of squabs by increasing crop milk protein synthesis through the TOR signaling pathway in the domestic pigeon (Columba livia).

Leucine (Leu) plays a critical regulatory role in protein synthesis, however, the effects and molecular mechanisms of Leu on crop milk protein in the domestic pigeons (Columba livia) are still unknown. Therefore, the study aimed to investigate the effects of dietary Leu supplementation on crop milk protein synthesis and the growth performance of squabs and the possible underlying mechanism. A total of 240 pairs of breeding pigeons (1102.3 ± 9.5 g/pair) were randomly assigned to 1 of 5 treatments, including a positive control (PC) diet that had adequate crude protein (crude protein, CP = 18%; Leu = 1.30%), a negative control (NC) diet that was low in CP (CP = 16%, Leu = 1.30%), and NC diets supplemented with Leu at 0.15%, 0.45%, or 1.05%. Compared with the NC diet, 0.15 to 0.45% Leu supplementation decreased BW loss and increased relative crop weight, crop thickness, and protein levels in the crop tissue and milk of breeding pigeons. However, dietary supplementation with 1.05% Leu inhibited ADFI in breeding pigeons. Dietary supplementation with 0.15 to 0.45% Leu decreased the mortality rate and increased the BW, eviscerated yield, and breast muscle yield of young squabs. The protein expression levels of the target of rapamycin (TOR), ribosomal protein S6 kinase 1 (S6K1), ribosomal protein S6 kinase (S6), eukaryotic initiation factor 4E binding protein 1 (4EBP1), and eukaryotic translation initiation factor 4E (eIF4E) were upregulated in the crop tissue of breeding pigeons in PC, 0.15% and 0.45% Leu-supplemented groups. Collectively, these results indicated that 0.15 to 0.45% Leu supplementation could decrease BW loss, increase milk protein synthesis in the crop of breeding pigeons, and enhance the survival rate and growth performance of young squabs through the TOR signaling pathway.

Expression analyses of candidate genes related to meat quality traits in squabs from two breeds of meat-type pigeon.

In this study, meat quality traits were compared between squabs from two pigeon breeds: one Chinese indigenous breed, the Shiqi (SQ) meat-type pigeon, and an imported breed, the white king (WK) meat-type pigeon. Breed differences were detected in the content of intramuscular fat (IMF) in the breast muscle. SQ squabs had significantly higher IMF content than the WK birds. The shear force value (an objective measure of meat tenderness) of SQ birds was also relatively lower than that of the WK squabs. Further analysis of fatty acids profile revealed that SQ squabs exhibited significant advantage in the synthesis of polyunsaturated fatty acids, while WK squabs were significantly higher in the sum of monounsaturated fatty acids. Breast muscle in the SQ squabs was also significantly higher in the ratio of polyunsaturated fatty acids to saturated fatty acids, as well as the sum of omega 6 fatty acids. Variability of expression levels of functional genes in relation to fat accumulation and meat tenderness was analysed by qRT-PCR. Gene expression analyses showed that the hepatic expression of LPL (lipoprotein lipase), FABP4 (fatty acid-binding protein 4), and CAPN2 (calpain-2) were significantly higher in the SQ squabs. In the breast muscle tissue, the FABP3 (fatty acid-binding protein 3) and CAPN2mRNA abundance was significantly higher in SQ squabs. Our results suggested that these differentially expressed genes might be candidate genes used in the programmes of targeted selection for squabs with higher IMF content, tender meat, and more favourable fatty acids composition.

Gene expression of amino acid transporter in pigeon (Columbia livia) intestine during post-hatch development and its correlation with amino acid in pigeon milk.

This study was conducted to evaluate gene expression of the amino acid transporter in post-hatch pigeon small intestine and the association of pigeon milk amino acid with the above transporter's gene expression. A total of 48 pigeon breeding families were randomly allocated to 8 groups of 6 replicates of one parental pigeon pair and 2 squabs. Samples of pigeon milk and duodenum, jejunum, and ileum were collected on d 1, 2, 3, 4, 6, 8, 10, and 14 post hatch. The results showed that levels of crude protein (8.93 to 15.56%) were highest in pigeon milk on an air-dry basis. Amino acid content in pigeon milk remained constant in the first 4 d, declined abruptly at d 6, then increased dramatically from d 8 to 14. There was a significant effect of interaction between age and intestinal segments on those amino acid transporters gene expression. mRNA abundance of ATB0'+, SNAT-2, LAT-4, rBAT, b0'+AT, EAAT-3 and PAT-1 was highest in the ileum; B0AT1, asc-1, and IMINO were predominate in the jejunum; and CAT-1 and y+LAT2 were greatest in the duodenum. Age-related changes of amino acid transporter mRNA was inconsistent. mRNA levels of SNAT-2, rBAT, y+LAT2, b0'+AT, and EAAT-3 ascended with age, whereas that of asc-1, CAT-1, and IMINO diminished significantly. Levels of B0AT1 and PAT-1 mRNA abundance were minimized at d 6. However, few correlations were found between pigeon milk amino acid and the amino acid transporter gene expressions in squab small intestine. Our findings provide a comprehensive elaboration on ontogeny of the amino acid transporter in post-hatch pigeon intestine.

Transcriptomic Analysis Identifies Candidate Genes Related to Intramuscular Fat Deposition and Fatty Acid Composition in the Breast Muscle of Squabs (Columba).

Despite the fact that squab is consumed throughout the world because of its high nutritional value and appreciated sensory attributes, aspects related to its characterization, and in particular genetic issues, have rarely been studied. In this study, meat traits in terms of pH, water-holding capacity, intramuscular fat content, and fatty acid profile of the breast muscle of squabs from two meat pigeon breeds were determined. Breed-specific differences were detected in fat-related traits of intramuscular fat content and fatty acid composition. RNA-Sequencing was applied to compare the transcriptomes of muscle and liver tissues between squabs of two breeds to identify candidate genes associated with the differences in the capacity of fat deposition. A total of 27 differentially expressed genes assigned to pathways of lipid metabolism were identified, of which, six genes belonged to the peroxisome proliferator-activated receptor signaling pathway along with four other genes. Our results confirmed in part previous reports in livestock and provided also a number of genes which had not been related to fat deposition so far. These genes can serve as a basis for further investigations to screen markers closely associated with intramuscular fat content and fatty acid composition in squabs. The data from this study were deposited in the National Center for Biotechnology Information (NCBI)'s Sequence Read Archive under the accession numbers SRX1680021 and SRX1680022. This is the first transcriptome analysis of the muscle and liver tissue in Columba using next generation sequencing technology. Data provided here are of potential value to dissect functional genes influencing fat deposition in squabs.

Parent-offspring behavior of Jambu fruit doves (Ptilinopus jambu).

Fruit doves (Ptilinopus) constitute a genus of small to medium-sized, brightly colored arboreal birds, whose diets consist entirely of fruit. Little is known about the behavior of fruit doves because most species inhabit dense forests and are difficult to observe in the wild. This study describes the parental behavior of Jambu fruit dove pairs (Ptilinopus jambu) in a captive breeding program at the Saint Louis Zoo. Continuous video recordings were made of three pairs which raised a total of eight squabs over 2 years; daily rates of parental and squab behaviors were quantified. Overall, females were present at the nest, brooded their squabs, pecked, and attempted feedings more often than males. Parents also cared for their squabs at different times throughout the day. Males fed and brooded squabs during the middle of the day, while females fed throughout the day and brooded in the morning, evening, and overnight. Feeding rates were lower than those described for seed-eating doves (Columbinae), with hours between consecutive feedings, and squabs rarely begged before feeding events. Most squab behaviors involved initiating or terminating brooding and self-preening. These behaviors increased as squabs approached fledging, and coincided with a shift from full to partial brooding, and a decrease in parental allopreening. Older squabs also initiated feeding less frequently. Together, these data provide the first description of parental behavior in a Ptilinopus fruit dove. The results of this study may help improve captive breeding efforts, which are likely to become increasingly important for future conservation and reintroduction programs.

Una experiencia como coordinadora en grupo operativo / An experience as an operating group coordinator

El texto que a continuación expondré, nace de la reflexión y vivencia de un grupo operativo en particular, como un intento de formalizar dicha experiencia, acentuando los interrogantes en el lugar del coordinador, que dicho sea de paso, nos permita pensar y redimensionar dicho lugar en la intervención y coordinación de grupos operativos.

The text that I will present below, stems from the reflection and experience of a particular operating group, as an attempt to formalize this experience, emphasizing the questions in the place of the coordinator, which, incidentally, allows us to think and resize said place in the intervention and coordination of operational groups.

El E.C.R.O. y su concepción del sujeto en Enrique Pichón Rivière / The E.C.R.O. and his conception of the subject in Enrique Pichón Rivière

Es inevitable recurrir a textos que ya se han ocupado de reflexionar sobre los asuntos de nuestro interés hoy. Estos textos de los que me serviré son Procesos grupales de Enrique Pichón Rivière, y el de Gladis Adamson La psicología social frente al tercer milenio. Intentaré, pues, hablar sobre el ECRO y la concepción del sujeto que tiene Pichón, no sin dejar de confesar que dejaré abiertas múltiples preguntas, que quizás podamos trabajar en este seminario.

It is inevitable to resort to texts that have already taken care to reflect on the issues of our interest today. These texts that I will use are Enrique Pichón Rivière's group processes, and Gladis Adamson's The social psychology against the third millennium. I will try, then, to talk about the ECRO and the conception of the subject that Pichón has, not without ceasing to confess that I will leave multiple questions open, that perhaps we can work in this seminar.

Grupos operativos: sobre la operatividad / Operating groups: on operability

Este trabajo lo realizo a partir del desarrollo de un concepto, es decir, tratando de rastrear elementos para su construcción. Como el concepto elegido es «operatividad¼, esto hace que también se presente un eje de trabajo que tal vez enfatice mucho en la técnica, lo cual no quiere decir que sea el único eje a partir del cual se pueda investigar la propuesta de los grupos operativos. (Otros ejes podrían ser por ejemplo el concepto de salud, de sujeto, etc. en los que se soportan los grupos operativos).

I carry out this work based on the development of a concept, that is, trying to trace elements for its construction. As the concept chosen is "operability", this also makes it possible to present a work axis that may emphasize a lot in the technique, which does not mean that it is the only axis from which the group's proposal can be investigated operational (Other axes could be for example the concept of health, of subject, etc. in which the operative groups are supported).