10 research outputs found
Intratesticular hypertonic sodium chloride solution treatment as a method of chemical castration in cattle
AbstractCastration of male calves is necessary for trading to facilitate handling and prevent reproduction. However, some methods of castration are traumatic and lead to economic losses because of infection and myiasis. The objective of the present study was to evaluate the efficiency of intratesticular injection (ITI) of hypertonic sodium chloride (NaCl; 20%) solution in male calf castration during the first weeks of life. Forty male calves were allocated to one of the following experimental groups: negative controlâsurgically castrated immediately after birth; positive control âintact males; G1âITI from 1- to 5-day old; G2âITI from 15- to 20-day old; and G3âITI from 25- to 30-day old. Intratesticular injection induced coagulative necrosis of Leydig cells and seminiferous tubules leading to extensive fibrosis. Testosterone secretion and testicular development were severely impaired in 12-month-old animals from G1 and G2 groups (PÂ <Â 0.05), in which no testicular structure and sperm cells were observed during breeding soundness evaluation. Rectal and scrotal temperatures were not affected by different procedures. In conclusion, ITI of hypertonic NaCl solution induces sterility and completely suppresses testosterone secretion when performed during the first 20Â days of life
Ovarian Aging And The Activation Of The Primordial Follicle Reserve In The Long-Lived Ames Dwarf And The Short-Lived Bgh Transgenic Mice
The aim of this study was to evaluate the effect of growth hormone (GH) in the maintenance of the ovarian primordial follicle reserve. Ovaries from 16 mo old GH-deficient Ames Dwarf (df/df) and Normal (N/df) mice were used. A subgroup of df/df and N mice received GH or saline injections for six weeks starting at 14 mo of age. In addition, ovaries from 12 mo old mice overexpressing bovine GH (bGH) and controls were used. df/df mice had higher number of primordial and total follicles than N/df mice (p \u3c 0.05), while GH treatment decreased follicle counts in both genotypes (p \u3c 0.05). In addition, bGH mice had lower number of primordial and total follicles than the controls (p \u3c 0.05). pFoxO3a levels were higher in mice treated with GH and in bGH mice (p \u3c 0.05) when comparing with age match controls. These results indicate that increased circulating GH is associated with a reduced ovarian primordial follicle reserve and increased pFoxO3a content in oocytes
Buserelina na inseminação artificial em tempo fixo de ovelhas.
O estudo foi desenvolvido com o objetivo de avaliar o uso da buserelina na IATF em ovelhas durante a estação reprodutiva, associado ou não a eCG
Preservation of Meat Products with Bacteriocins Produced by Lactic Acid Bacteria Isolated from Meat
Bacteriocins are ribosomal-synthesized antimicrobial peptides that inhibit the growing of pathogenic and/or deteriorating bacteria. The most studied bacteriocin-producing microorganisms are lactic acid bacteria (LAB), as they have great potential application in food biopreservation, since the majority have GRAS (Generally Recognized as Safe) status. The LAB-producing bacteriocins and/or bacteriocins produced by these bacteria have been widely studied, with the emphasis on those derived from milk and dairy products. On the other hand, isolates from meat and meat products are less studied. The objective of this review is to address the main characteristics, classification, and mechanism of action of bacteriocins and their use in food, to highlight studies on the isolation of LAB with bacteriocinogenic potential from meat and meat products and also to characterize, purify, and apply these bacteriocins in meat products. In summary, most of the microorganisms studied are Lactococcus, Enterococcus, Pediococcus, and Lactobacillus, which produce bacteriocins such as nisin, enterocin, pediocin, pentocin, and sakacin, many with the potential for use in food biopreservation
Histological description of Cerdocyon thous (Linnaeus, 1766) respiratory system
ABSTRACT: The massive agricultural expansion converted the Cerdocyon thous, a South American native predator, in vulnerable specie. Basic data, such as histological description, are important to raise awareness on animal species, helping on preservation strategies. Considering the difficult in obtain samples, as the euthanasia of wild animals for this purpose is not allowed, data on histology are very scarce or inexistent. The objective of this paper was to provide a detailed histological description of the trachea and bronchial tree of the crab-eating fox Cerdocyon thous (Linnaeus, 1766). The specimens (one adult male and one adult female) used were provided by the Federal University of Pelotas (Pelotas, RS, Brazil) Rehabilitation Center of Wild Fauna (NURFS). Tissue samples were fixed in 10% formalin and included in paraffin. After slicing, samples were stained with HE (hematoxylin and eosin), PAS (periodic acid-Schiff) and resorcin fuchsin. Trachea had an average diameter of 7.87mm, and approximately 57% of the mucosa ciliated pseudo-stratified columnar epithelium was composed of goblet cells, mostly in the dorsal region. Bronchia and bronchioles had a mucosal fold with higher number of goblet cells. Using all these techniques there is no great remarkable differences from C. thous trachea and lung, when compared with the previous described structures for carnivores and most mammals, except for the goblet cells âregionalizationâ. Described results are important to understand the animal physiological and behavioral habits, allowing the development of preservation and protection strategies
Severe body condition loss lowers hepatic output of IGF1 with adverse effects on the dominant follicle in dairy cows
The severe loss of body condition score (BCS) during the early lactation period has been associated with infertility in cows. However, the mechanisms are not fully understood. The aim of this study was to examine the effect of BCS loss on liver health, and ovarian functions in cows during early lactation. Retrospectively multiparous cows from two farms were categorized based on units of BCS (1â5 scale) loss as Moderate (MOD, <0.75 units; n = 11) or Severe (SEV, â„0.75 units; n = 9) loss groups. From Weeks â3 to 7, relative to calving, MOD and SEV cows lost on average 0.4 and 1.0-unit BCS, respectively. All data except hepatic transcriptomes were analyzed with PROC MIXED procedure of SAS. The plasma concentration of non-esterified fatty acids at Week 0 and 1, Ă-hydroxy butyrate at Week 1, and Îł-glutamyl transferase at Weeks 1 and 7 relative to calving were higher in SEV cows. Hepatic transcriptome analysis showed that 1 186 genes were differentially expressed in SEV (n = 3) compared to MOD (n = 3) cows at Week 7 after calving. Pathway analysis revealed that significant DEGs in SEV cows enriched in lipid metabolisms including, lipid metabolic process, ether lipid metabolism, fatty acid beta-oxidation, fatty acid biosynthetic process, fatty acid metabolic process, fat digestion and absorption, linoleic acid metabolism, alpha-linolenic acid metabolism. The impaired liver function in SEV cows was associated with 1.5-fold reduction of hepatic IGF1 gene expression and lower serum IGF1 concentrations. At the ovarian level, SEV cows had lower IGF1 concentration in the follicular fluid of the dominant follicle of the synchronized follicular wave compared to that of MOD cows at 7 weeks after calving. Further, the follicular fluid concentration of estradiol-17ÎČ was lower in SEV cows along with lower transcript abundance of genes from granulosa cells associated with dominant follicle competence, including CYP19A1, NR5A2, IGF1, and LHCGR. These data show that SEV loss of BCS during early lactation leading up to the planned start of breeding is associated with liver dysfunction, including lower IGF1 secretion, and impaired function of the dominant follicle in the ovary
Growth Hormone Increases DNA Damage in Ovarian Follicles and Macrophage Infiltration in the Ovaries
Evidence points to an important role of the growth hormone (GH) in the aging process and longevity. GH-deficient mice are smaller, live longer than normal littermates, and females have an increased ovarian reserve. The aim of the study was to evaluate the role of GH in the ovarian reserve by evaluating DNA damage, macrophage infiltration, and granulosa cell number in primordial and primary follicles. Experiment 1 used GH-deficient Ames dwarf mice (df/df, n = 12) and their normal littermates (N/df, n = 12), receiving GH or saline injections. Experiment 2 included transgenic mice overexpressing bovine GH (bGH) (n = 6) and normal mice (N, n = 6). DNA damage (anti-ÎłH2AX) and macrophage counting (anti-CD68) were evaluated by immunofluorescence. Female df/df mice had lower ÎłH2AX foci intensity in both oocytes and granulosa cells of primordial and primary follicles (p \u3c 0.05), indicating fewer DNA double-strand breaks (DSBs). GH treatment increased DSBs in both df/df and N/df mice. Inversely, bGH mice had a higher quantity of DSBs in both oocytes and granulosa cells of primordial and primary follicles (p \u3c 0.05). Df/df mice showed ovarian tissue with less macrophage infiltration than N/df mice (p \u3c 0.05) and GH treatment increased macrophage infiltration (p \u3c 0.05). In contrast, bGH mice had ovarian tissue with more macrophage infiltration compared to normal mice (p \u3c 0.05). The current study shows that GH increases DNA DSBs in oocytes and granulosa cells and raises macrophage infiltration in the ovaries, pointing to the role of the GH/IGF-I axis in maintenance of oocyte DNA integrity and ovarian macrophage infiltration in mice
Effect of Caloric Restriction and Rapamycin on Ovarian Aging in Mice
Caloric restriction (CR) increases the preservation of the ovarian primordial follicular reserve, which can potentially delay menopause. Rapamycin also increases preservation on the ovarian reserve, with similar mechanism to CR. Therefore, the aim of our study was to evaluate the effects of rapamycin and CR on metabolism, ovarian reserve, and gene expression in mice. Thirty-six female mice were allocated into three groups: control, rapamycin-treated (4 mg/kg body weight every other day), and 30% CR. Caloric restricted females had lower body weight (P \u3c 0.05) and increased insulin sensitivity (P = 0.003), while rapamycin injection did not change body weight (P \u3e 0.05) and induced insulin resistance (P \u3c 0.05). Both CR and rapamycin females displayed a higher number of primordial follicles (P = 0.02 and 0.04, respectively), fewer primary, secondary, and tertiary follicles (P \u3c 0.05) and displayed increased ovarian Foxo3a gene expression (P \u3c 0.05). Despite the divergent metabolic effects of the CR and rapamycin treatments, females from both groups displayed a similar increase in ovarian reserve, which was associated with higher expression of ovarian Foxo3a