Genetic variation of in vivo muscle glycerol,glycogen, and pigment in Danish purebred pigs

Heritability values of glycerol, glycogen and pigment concentrations measured on muscle biopsy samples from longissimus dorsi obtained from 85?kg boars of Danish purebred pigs (Landrace, Yorkshire, and Duroc) and their genetic correlations to performance and meat quality traits were calculated. The heritability values of glycogen, pigment, and glycerol were 0.38±0.02, 0.17±0.02, and 0.065±0.016, respectively. Glycogen was negatively related to the feed conversion ratio (FCR) (r _g =?0.25±0.06) and ultimate meat pH (r _g =?0.41±0.04), and positively to the carcass meat percentage (r _g =0.35±0.04), L* (lightness of meat, r _g =0.32±0.04) and a* (redness of meat, r _g =0.12±0.03). Pigment was positively related to the FCR (r _g =0.12±0.05), the meat percentage (r _g =0.28±0.05), and a* (r _g =0.59±0.04), and negatively to the L* (r _g =?0.46±0.06). The concentrations of pigment and glycogen (r _g =0.27±0.05) were interrelated. Based on the heritability values and the signs of the genetic correlations the present data suggest that it is possible to select for higher ultimate pH and improved colour by selection for either lower muscle glycogen or higher pigment concentration, respectively. However, the positive genetic correlation between these two traits may restrict the efficiency of simultaneous selection for lower glycogen and higher pigment. All genetic parameter estimates presented are calculated across three purebreds. Values for each breed are warranted for use in pig production. However, this requires more animals per breed.     

Plasma growth hormone concentrations during growth in turkeys

1. The concentrations of circulating GH were low in 1‐week‐old birds (male plasma pool 30 ng/ml, female 32 ng/ml), reached a maximum at 7 weeks in male birds (142 ± 26 SEM ng/ml) or 4 weeks in females (185 ± 32 ng/ml) and then decreased to 17.3 ± 2–8 ng/ml in males and 8?7 ± 0–6 ng/ml in females at 17 weeks.

2. Significant inverse correlations between GH concentration and age or body weight were found (male, r = —0–693), female, r = —0–623).

3. In males, but not females, the weekly increase in body weight was correlated with the plasma GH concentration (r = 0–291).     

Stimulated growth hormone release in juvenile cattle genetically selected for high and low milk yield

The purpose of the present study was to test if plasma growth hormone (GH) concentrations in juvenile male and female cattle before or after intravenous stimulation with secretagogues was affected by selection for high (H) vs. low (L) milk yield in lines of Norwegian cattle. In the first of two experiments (A), 32 yearling heifers (16 H and 16 L, at 307–424 days of age) were tested by use of four doses of growth hormone releasing factor (GRF); 0.02, 0.10, 0.50 and 2.50 μg/kg live weight, on 4 consecutive days. The animals were fed ad libitum on a silage-based ration before and during the experiment. Growth hormone was assayed in plasma from blood samples taken at ?15, ?5, 0, 5, 10, 15, 20, 30, 45 and 60 min from stimulation. Plasma GH concentrations were log transformed before statistical analyses. Response variables were; PRIOR (mean of ?15, ?5 and 0 min samples) and PEAK (mean of 10, 15 and 20-min samples). In experiment B, 37 calves (19 H+18 L, 22 males and 15 females, age 114–259 days) were subjected daily to one of three intravenous stimulation tests (GRF, 0.10 and 0.50 μg/kg or thyrotrophin releasing hormone (TRH) at 0.20 μg/kg live weight) on each of 3 consecutive days. Feeding was restricted to cover estimated maintenance requirements only. Rations were given once daily during the test days and 3 days prior to first test. Blood sampling and variables followed those of experiment A. Selection line did not significantly affect GH variables in experiments A or B at any dose of GRF or TRH. GH response increased with increasing dose of GRF up to 0.50 μg/kg. At the highest GRF dose, the response was delayed and persisted longer. Doses giving intermediate to large response increased repeatability of GH measurements. It is concluded that GH secretion in juvenile cattle can be accurately assessed using GRF based stimulation tests combined with restricted and controlled feeding, but it is not affected by selection for milk yield in Norwegian cattle.     

Energy and protein requirements of weaned male and female Saanen goats

The objective of this research was to estimate the energy and protein requirements for maintenance and growth in male (castrated and intact) and female Saanen goat kids between 15 and 30 kg BW. To determine the net energy requirements for maintenance (NE_m) and the net protein requirements for maintenance (NP_m), 75 goats (25 castrated and 26 intact males and 24 females) were used. Twenty‐one goats (seven castrated and eight intact males and six females) were randomly assigned for slaughter to estimate the initial empty body composition. The 54 remaining animals (18 castrated and 18 intact males and 18 females) were randomly assigned in a split‐plot design using a 3 × 3 factorial arrangement with three sexes and three levels of intake (ad libitum and restricted feed to 75% or 50% of the ad libitum intake). Within each sex, six blocks (three goats per block) were formed and one goat was randomly assigned to each level of intake. The 75% and the 50% of ad libitum rationing were determined daily, based on the DMI of the animal fed ad libitum on the previous day. All animals within block were slaughtered when the animal fed ad libitum reached 30 kg BW. The net energy requirements for gain (NE_g) and the net protein requirements for gain (NP_g) were obtained using 58 animals (20 castrated and 20 intact males and 18 females). The animals were fed ad libitum and slaughtered at targeted BW (15, 23 or 30 kg). Sex did not affect NE_g and NP_m (277.8 kJ/kg^0.75 BW day and 2.98 g CP/kg^0.75 BW day respectively), as well as NP_g (180.9 ± 6.48 g/kg EBW gain) in Saanen goat kids. However, castrated males and females had similar NE_g (varied from 12.6 ± 0.424 to 17.9 ± 1.38 MJ/kg EBW gain), greater than intact males (varied from 9.74 ± 0.420 to 10.7 ± 0.984 MJ/kg EBW gain), as the BW increased from 15 to 30 kg.     

Estimation of genetic parameters for the prevalence of osseous fragments in limb joints of Hanoverian Warmblood horses

Genetic parameters were estimated for the prevalence of osseous fragments in distal (DIJ) and proximal interphalangeal (PIJ), fetlock (FJ) and hock joints (HJ) of Hanoverian Warmblood horses by using residual maximum likelihood (REML) with linear animal models. The analyses were based on the results of 10 standardized radiographs of all four limbs of 3725 young riding horses selected for sale at auction. Transformation factors onto the underlying liability scale were verified by a simulation study. The heritability estimates of osseous fragments on the liability scale were in the range of h² = 0.19–0.60. Further analyses of osseous fragments in FJ and HJ were performed separately in males and females. In both sexes, the heritabilities of osseous fragments in HJ were higher (h² = 0.41 in males, h² = 0.25 in females) than those of osseous fragments in FJ (h² = 0.21 in males, h² = 0.23 in females). Osseous fragments in the phalangeal joints (DIJ, PIJ, FJ) were genetically correlated moderately positive (r_g = 0.19–0.41). The genetic correlations between osseous fragments in the phalangeal joints and in HJ were negative (r_g = ?0.27 to ?0.67). Particularly, this applied to osseous fragments in FJ in both sexes, to those in front FJ in males and to osseous fragments in front and hind FJ of females (up to r_g = ?1). The heritability of height at withers was estimated at h² = 0.27–0.28. Genetic correlations between height at withers and osseous fragments in equine limb joints were mostly moderately positive (up to r_g = 0.75). We conclude from our results that osseous fragments in phalangeal and hock joints are genetically different traits but sex‐specific expression of osseous fragments was unlikely.     

Morphometric analysis of the spinal cord of the Sus scrofa (large white and landrace crossbreed)

The incidence of spinal cord (SC) injury in developed and undeveloped countries is alarming. The pig (Sus scrofa) has been recommended as a suitable research model for translational studies because of its morphophysiological similarities of organ systems with humans. There is a dearth of information on the SC anatomy of the large white and landrace crossbreed (LW-LC) pigs. We therefore aim to describe the gross morphology and morphometry of its SC. Twelve juvenile LW-LC pigs (six males and six females) were used. The skin and epaxial muscles were dissected to expose the vertebral column. The SC was carefully harvested by laminectomy, and 13 gross SC morphometric parameters were evaluated. Thirty-three spinal nerves were seen emanating from either side of the SC by means of dorsal and ventral spinal roots. The overall average of SC length and weight was 36.23 ± 1.01 cm and 16.60 ± 0.58 g, respectively. However, the mean SC length and weight were higher in females compared with males, with SC weight being statistically significant. A positive relationship between SC length and weight was significant for males (p = 0.0435) but not for females (p = 0.42). Likewise, the strength of the relationship between SC length and weight was significant in males (r = 0.82) but not significant in females (r = 0.41). Baseline data for the morphometric features of the spinal cord in the LW-LC pigs were generated, which will contribute to the knowledge of this species anatomy and useful information on regional anaesthesia that should further strengthen the drive in adopting the pig as a suitable research model for biomedical research.     

Implications of genetic selection on yolk proportion on the dry matter content of eggs in a White Leghorn population

1. The responses to genetic selection on yolk proportion as a technique for increasing egg dry matter content, an important criterion for the egg-product industry, was investigated in a pedigree flock of White Leghorn hens.

2. Parents were preselected on high and low yolk proportion from a base population. The absolute estimated breeding value for yolk proportion of both groups differed by 3%. The realised selection difference in dry matter content of eggs between groups was more than 1% in the analysed offspring population.

3. Heritability estimates were moderate and dry matter had a lower heritability (h² = 0.39) than yolk proportion (h² = 0.44).

4. The genetic correlation between yolk proportion and dry matter content was highly positive (r_g = 0.91). Genetic correlations with egg weight were negative and would have to be compensated for in a breeding programme (r_g = ?0.76 with yolk proportion and r_g = ?0.64 with dry matter content). The genetic correlation between the laying performance and yolk proportion was r_g = 0.28 and close to zero (r_g = ?0.05) for dry matter content.

5. Easy recording and lower undesirable correlations make yolk proportion more suitable for commercial selection compared with egg dry matter content in layer breeding.     

Genetic parameters for body weights,egg traits and antibody response against Newcastle Disease Virus (NDV) vaccine among two Tanzania chicken ecotypes

Genetic parameters were estimated for production traits and primary antibody response (Ab) against Newcastle diseases virus (NDV) vaccine among two Tanzania chicken ecotypes viz. Kuchi and Tanzania Medium (Medium). Production traits studied were body weights at 8 (Bwt8), 12(Bwt12), 16(Bwt16), and 20 (Bwt20) weeks of age, age at first egg (AFE), egg number in the first 90 days after sexual maturity (EN-90), egg weight (EW), egg shell thickness (STH), and egg shape index (ESI). Heritability estimates for Bwt8, Bwt12, Bwt16, Bwt20, AFE, EN-90, EW, STH, ESI and Ab for Kuchi chicken were 0.38 ± 0.10, 0.41 ± 0.07, 0.44 ± 0.08, 0.45 ± 0.09, 0.42 ± 0.10, 0.31 ± 0.05, 0.43 ± 0.08, 0.53 ± 0.11, 0.48 ± 0.13 and 0.27 ± 0.06, respectively. Corresponding estimates for Medium ecotype were 0.39 ± 0.09, 0.43 ± 0.10, 0.42 ± 0.08, 0.43 ± 0.07, 0.52 ± 0.11, 0.32 ± 0.06, 0.50 ± 0.07, 0.61 ± 0.13, 0.52 ± 0.10 and 0.29 ± 0.05, respectively. Genetic (r _g) and phenotypic (r_p) correlations in both ecotypes were highest among body weights (i.e. r_g = 0.60 to 0.93 and r_p = 0.54 to 0.78), and were lowest (around 0.10 and below, ranging from positive to negative) among primary antibody response against NDV vaccine and production traits, and among eggshell thickness, egg shape index and other production traits. The magnitudes of heritability estimates obtained in this study indicate good prospects of improving these traits in both ecotypes through selection.     

Colour Doppler Ultrasonography as a Tool to Assess Luteal Function in Santa Inês Ewes

The aim of this study was to evaluate luteal dynamics in the Santa Inês ewes using colour Doppler (CD) ultrasonography. Oestrus was synchronized in nulliparous females (n = 18), and subsequently, they were only teased (n = 6) or teased and mated (n = 12). Blood samples were collected daily for plasma progesterone (P₄) concentrations. Ultrasonographic images of corpora lutea (CL) in CD mode were obtained for further analysis in its largest diameter. The CD mode allowed an early sequential monitoring of CL that was visualized by the first time 0.77 ± 0.62 days after ovulation, with luteal area 29.68 ± 13.21 mm². During the luteogenesis, a progressive increase was observed, followed by a plateau of luteal area, vascularization area and plasma concentrations of P₄ reaching maximum values in D11 (124.0 ± 38.0 mm², 52.78 ± 24.08 mm² and 11.23 ± 4.89 ng/ml, respectively). In the luteolysis, the plasma concentrations of P₄ decreased sharply, whereas luteal and vascularization area gradually. The vascularization area was positively correlated with plasma concentrations of P₄ during the luteogenesis (r = 0.22) and luteolysis (r = 0.48). The luteal dynamics of Santa Inês ewes showed patterns similar to those observed in other sheep breeds studied. The CD ultrasonography has the potential to be used as a tool to assess luteal function in sheep.     

Genetic variation for worm burdens in laying hens naturally infected with gastro-intestinal nematodes

1. Genetic parameters were determined for the worm burden of the most common gastro-intestinal nematodes in two chicken genotypes after being exposed to free-range farming conditions for a laying period.

2. Seventeen-week-old hens of 2 brown genotypes, Lohmann Brown (LB) plus (n = 230) and LB classic (n = 230), were reared for a laying period and subjected to post-mortem parasitological examinations at 79 weeks (LB plus) or 88 weeks (LB classic) of age.

3. There was no significant difference in faecal egg counts between the genotypes. Almost all hens (>99%) were infected with at least one nematode species. Species-specific nematode prevalence ranged from 85.8% to 99.1% between the two genotypes. Heterakis gallinarum was the most prevalent nematode (98.5%), followed by Ascaridia galli (96.2%) and Capillaria spp. (86.1%). Capillaria spp. were composed of C. obsignata (79%), C. caudinflata (16%) and C. bursata (5%).

4. All phenotypic and genetic correlations among worm counts of different parasite species were positive in combined genotypes (r_P ranged from 0.05 to 0.30 and r_G ranged from 0.29 to 0.88). A strong genetic correlation (r_G = 0.88 ± 0.34) between counts of A. galli and H. gallinarum was quantified. Heritability for total worm burden for LB plus and LB classic, respectively, were 0.55 ± 0.18 and 0.55 ± 0.34. Across both genotypes, the heritability of total worm burden was 0.56 ± 0.16.

5. In conclusion, there is a high variation attributable to genetic background of chickens in their responses to naturally acquired nematode infections. The high positive genetic correlation between counts of closely related worm species (e.g. A. galli and H. gallinarum) may indicate existence of similar genetically determined mechanism(s) in chickens for controlling these nematodes.

     

Improvement of the Culture Conditions for In Vitro Production of Cattle Embryos in a Portable CO2 Incubator

The effects of different concentrations of growth hormone (GH) on in vitro maturation (IVM), fertilization (IVF) and culture (IVC) of bovine oocyte/embryos in CR1aa or CR2aa media using a simple CO₂ incubator were investigated. The IVM/IVF/IVC of oocytes were carried out in the presence of 0, 50, 100 and 200 ng/ml GH in the medium. The proportion of metaphase II oocytes was significantly higher (p < 0.05) in 200 ng/ml compared with 0 ng/ml GH in CR1aa medium (59 versus 85%, respectively), but this effect was not observed under CR2aa. Higher concentrations of GH yielded lower rates of unfertilized ova and thus superior cleavage rates (36.5 ± 0.2 and 63.5 ± 2.0% versus 17.5 ± 0.2 and 82.5 ± 1.5% or 40.4 ± 0.6 and 59.6 ± 1.4% versus 16.6 ± 1.2 and 83.4 ± 6.2% for 0 and 200 ng/ml GH in portable or ordinary incubator, respectively) in CR1aa. This dose‐dependent effect was also observed in the percentages of transferable embryos, although not statistically different (17.2 ± 1.7 versus 27.3 ± 1.8% and 16.6 ± 3.1 versus 26.0 ± 1.4%, for 0 versus 200 ng/ml GH in portable and ordinary incubator, respectively). In contrast to the CR1aa, different concentrations of GH in CR2aa medium did not increase either fertilization or cleavage rates. In fact, higher concentrations of GH in this medium negatively affected the rate of transferable embryos. Hence, percentages of transferable embryos obtained in the portable incubator under 0 or 50 ng/ml GH were higher (p < 0.05) compared with those obtained in 100 or 200 ng/ml GH (35.4 ± 5.7 or 40.5 ± 5.4% versus 22.4 ± 2.4 or 15.5 ± 2.1%, respectively). There was however, no significant difference in the rate of transferable embryos in an ordinary incubator employing CR2aa medium, but the trend was more or less similar to that observed in the portable incubator. Despite the fact that relatively fewer oocytes were employed for the culture in the ordinary incubator, overall results observed employing the simple portable CO₂ incubator were within the range of those obtained in an ordinary incubator; implying that the simple portable incubator can effectively be employed for the in vitro production of bovine embryos under field conditions.     

Field evidence for colony size and aseasonality of breeding and in Ansell’s mole-rat,Fukomys anselli (Rodentia: Bathyergidae)

Ansell’s mole-rat, Fukomys anselli, is a cooperatively breeding bathyergid endemic to the Lusaka Province of Zambia. During a 12-month field study involving the capture of 33 colonies of mole-rats, the number of occupants, breeding females and sex ratio within colonies were recorded. While thirty of these social groups contained a single breeding queen, three were found to exhibit plural breeding among females, having two queens present simultaneously. Mean±S.E.M. colony size was 8.7±2.2 (range 6–16,n=33). The occurrence of plural breeding and small group size is consistent with the predictions of the aridity food distribution hypothesis for social species inhabiting mesic habitats. The sex ratio of the population was skewed towards females at 1.2:1. The mean mass of adult males was 63.0 ± 18.3 g (range 36.7–110.3, n=87) while that for adult females was 52.9±11.8 g (range 35.1–77.8, n=86). Pregnant and lactating females were found throughout the study period from February 2009 to February 2010, indicating an aseasonal pattern of breeding in this species. Autopsy of individuals (n=288) from the 33 colonies revealed a total of 19 pregnant females. Nine of these were in the latter stages of pregnancy and mean litter size was determined as 2.7 pups (range 1–4). Collectively, these new data reveal that Fukomys anselli share many similarities in life history and reproductive traits with the phylogentically closely related giant Zambian mole-rat, Fukomys mechowii.     

EFFECT OF VENTILATION TECHNIQUE AND AIRWAY DIAMETER ON BRONCHIAL LUMEN TO PULMONARY ARTERY DIAMETER RATIOS IN CLINICALLY NORMAL BEAGLE DOGS

In dogs, a mean broncho‐arterial ratio of 1.45 ± 0.21 has been previously defined as normal. These values were obtained in dogs under general inhalational anesthesia using a single breath‐hold technique. The purpose of the study was to determine whether ventilation technique and bronchial diameter have an effect on broncho‐arterial ratios. Four healthy Beagle dogs were scanned twice, each time with positive‐pressure inspiration and end expiration. For each ventilation technique, broncho‐arterial ratios were grouped into those obtained from small or large bronchi using the median diameter of the bronchi as the cutoff value. Mean broncho‐arterial ratios obtained using positive‐pressure inspiration (1.24 ± 0.23) were statistically greater than those obtained at end expiration (1.11 ± 0.20) P = 0.005. There was a strong positive correlation between bronchial diameter and broncho‐arterial ratios for both ventilation techniques (positive‐pressure inspiration r_s = .786, P < 0.0005 and end expiration r_s = .709, P < 0.0005). Mean broncho‐arterial ratio for the large bronchi obtained applying positive‐pressure inspiration was 1.39 cm ± 0.20 and during end expiration was 1.22 cm ± 0.20. Mean broncho‐arterial ratio for the small bronchi obtained during positive‐pressure inspiration was 1.08 cm ± 0.13 and during end expiration was 1.01 cm ± 0.13. There was a statistically significant difference between these groups (F = 248.60, P = 0.005). Findings indicated that reference values obtained using positive‐pressure inspiration or from the larger bronchi may not be applicable to dogs scanned during end expiration or to the smaller bronchi.     

Age estimation in the harbour seal (Phoca vitulina) based on the closure of skull sutures and synchondroses

Age estimation of individuals is an important tool for the management of marine mammals and is mostly done by microscopic analysis of growth layer groups (GLGs) in teeth (cementum and dentin) and bone. The present study evaluated the use of sutural and synchondrosal closure in the skull of the harbour seal (Phoca vitulina) as a potential non-destructive alternative for age estimation. For that, we scored the ectocranial closure of 12 selected sutures and synchondroses in a sample of 303 Eastern Atlantic harbour seals (P. v. vitulina; 138 males, 165 females), for which data on age at death were available, based on determined gross-morphological criteria in individuals younger than 1 year and cement layer analysis in canines in older individuals. A strong positive relationship between the sum of closure level scores (SCS) and age (males: r = 0.8797, females: r = 0.8825) was recorded, which was stronger than that for the relationship between age and condylobasal length (CBL, males: r = 0.7085, females: 0.7086) (all p-values <0.0001). In adult individuals (≥5 years), CBL was higher in males than females (p < 0.0001), while SCS did not significantly differ between the two sexes (p = 0.148). Our findings show that the analysis of sutural/synchondrosal closure is a valid alternative for age estimation in harbour seals, thereby confirming results of previous studies on other pinniped species.     

Does heterosexual experience matter for bucks' homosexual mating behavior?

Our aim was to compare bucks' homosexual mating behavior after mixing 2 groups of bucks, one that was reared in permanent contact and another in complete isolation from female goats, and determine if this behavior was related with testosterone concentration. Two groups of 1-year-old Saanen bucks were reared in permanent contact with 4 adult females until 1 week before the experiment (n = 8; group RF) or isolated from females (n = 9; group RI). When bucks were 1 year old, both groups were mixed (day 0), and mount attempts and matings were recorded on days 1, 3, 6, and 9. Testosterone concentrations were determined by radioimmnoassay from blood samples collected twice daily on days ?7, 0, 1, 3, 6, and 9. Each RI male attempted to mate more RF than RI males (31.9 ± 5.1% vs. 16.7 ± 3.6%, respectively; P = 0.01), but there was no difference on the frequency in which RF males attempted to mate RI (19.4 ± 0.1%) or RF (11.1 ± 0.1%) males (P = 0.24). Similarly, RI males mated more RF than RI males (12.5 ± 2.9% vs. 5.6 ± 0.02%, respectively; P = 0.04). Furthermore, there was no difference on the frequency in which RF males mated RI (10.7 ± 8.9%) or RF (3.6 ± 0.02%) males (P = 0.23). Testosterone concentrations tended to be greater in RF than RI (P = 0.054), but no interaction between time and group was observed (P = 0.13). We propose that as RI bucks never had contact with females, they directed their sexual behavior toward other males that had the stimulating effect of the novelty. On the other hand, for RF bucks, although the novelty effect of the new bucks existed, the previous knowledge of females determined that other bucks were not considered as highly sexual attractive. This difference was not related to the differences in testosterone concentration.     

Genetic parameters for the prediction of abdominal fat traits using blood biochemical indicators in broilers

1. Excessive deposition of body fat, especially abdominal fat, is detrimental in chickens and the prevention of excessive fat accumulation is an important problem. The aim of this study was to identify blood biochemical indicators that could be used as criteria to select lean Yellow-feathered chicken lines.

2. Levels of blood biochemical indicators in the fed and fasted states and the abdominal fat traits were measured in 332 Guangxi Yellow chickens. In the fed state, the genetic correlations (r_g) of triglycerides and very low density lipoprotein levels were positive for the abdominal fat traits (0.47 ≤ r_g ≤ 0.67), whereas total cholesterol, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) showed higher negative correlations with abdominal fat traits (–0.59 ≤ r_g ≤ ?0.33). Heritabilities of these blood biochemical parameters were high, varying from 0.26 to 0.60.

3. In the fasted state, HDL-C:LDL-C level was positively correlated with abdominal fat traits (0.35 ≤ r_g ≤ 0.38), but triglycerides, total cholesterol, HDL-C, LDL-C, total protein, albumin, aspartate transaminase, uric acid and creatinine levels were negatively correlated with abdominal fat traits (–0.79 ≤ r_g ≤ ?0.35). The heritabilities of these 10 blood biochemical parameters were high (0.22 ≤ h² ≤ 0.59).

4. In the fed state, optimal multiple regression models were constructed to predict abdominal fat traits by using triglycerides and LDL-C. In the fasted state, triglycerides, total cholesterol, HDL-C, LDL-C, total protein, albumin and uric acid could be used to predict abdominal fat content.

5. It was concluded that these models in both nutritional states could be used to predict abdominal fat content in Guangxi Yellow broiler chickens.     

Platelet‐Activating Factor and Evidence of Oxidative Stress in the Bronchoalveolar Fluid of Thoroughbred Colts during Race Training

Background: Inflammatory airway disease (IAD) is prevalent in young racehorses during training, being the 2nd most commonly diagnosed ailment interrupting training of 2‐year‐old Thoroughbred racehorses. Hypothesis: That stabling and exercise cause oxidative stress, release of platelet‐activating factor (PAF) and inflammation in airways of Thoroughbred colts. Animals: Colts in breeding farms (NC, n = 45), stabled for 30 days (EC, n = 40), and race trained (EX, n = 34). Methods: Cytological profile and parameters of bronchoalveolar lavage fluid (BALF) related to oxidative stress, bioactivity of the proinflammatory mediator PAF, catalase activity, and alveolar macrophage function. Results: Percentages of neutrophils and eosinophils in the BALF of the EX group were higher (5.4 ± 6.4% versus 0.9 ± 1.2%) than the upper limits for normal horses (3–5%). BALF from the EX group (45.6 ± 2.8 cells/μL of BALF) also displayed significantly (P= .017) higher total nucleated cell count. PAF bioactivity and the total protein concentration in the BALF were higher in the EX group (0.0683 ± 0.076 versus 0.0056 ± 0.007 340 : 380 nm ratio P= .0039, 0.36 ± 0.30 versus 0.14 ± 0.15 mg of proteins/mL of BALF P < .001). Concentration of BALF hydroperoxides was higher in the EC group (104.7 ± 80.0 versus 35.2 ± 28.0 nmol/mg of proteins, P= .013) and catalase activity was higher in the EX group (0.24 ± 0.16 versus 0.06 ± 0.02 μmol H₂O₂/min/mg of proteins, P= .0021). Alveolar macrophage phagocytosis (P= .048) as well as production of superoxide anion (P= .0014) and hydrogen peroxide (P= .0011) were significantly lower in EX group. Conclusions and Clinical Importance: Further studies should be performed to elucidate the role of PAF in the pathophysiology of IAD. Its presence in bronchoalveolar fluid of young athletic horses makes it a potential therapeutic target to be investigated.     

Sex Steroid Levels in XY Males and Sex‐Reversed XX Males,of Rainbow Trout (Oncorhynchus mykiss), During the Reproductive Cycle

In this study, the annual cycle of the gonadal steroids testosterone (T), 11‐ketotestosterone (11‐KT), 17β‐oestradiol (E2) and 17α, 20β‐dihydroxy‐4‐pregnen‐3‐one (DHP) was determined using radioimmunoassay and then compared, for XY males (n = 35) and sex‐reversed XX males (n = 27) rainbow trout, to establish possible endocrinology differences. Both in XY males and sex‐reversed XX males, significant correlation was shown between body weight and T (r = 0.5046 and 0.34078, respectively; p < 0.0001) or KT (r = 0.52494 and 0.43545, respectively; p < 0.0001) concentrations. Plasma androgen levels in XY and sex‐reversed XX males were similar and showed an intense seasonal variation. The highest levels for T and 11‐KT were detected from December to April with a peak in January (51.67 ± 5.11 and 61.95 ± 4.25 ng/ml, for XY males and 57.1 ± 5.82 and 59.27 ± 4.84 ng/ml, respectively, for XX males). In addition, there was a positive correlation (p < 0.0001) between T and 11‐KT levels for XY males (r = 0.7533) and sex‐reversed XX males (r = 0.6019). Concentrations of DHP in XY males also showed seasonal variation with a peak in February (25.18 ± 12.99 ng/ml). However, DHP levels in sex‐reversed XX males were undetectable (<0.1 ng/ml) over the year. Levels of E2 were undetectable through the year in both groups of trout. In conclusion, the androgenic and oestrogenic profiles of sex‐reversed XX males were similar to those observed in XY males. The only difference in the annual gonadal steroid cycle between XY and sex‐reversed XX males was in the DHP profile.     

Assessment of Sperm Function Parameters and DNA Fragmentation in Ejaculated Alpaca Sperm (Lama Pacos) by Flow Cytometry

Flow cytometry has been shown to be an accurate and highly reproducible tool for the analysis of sperm function. The main objective of this study was to assess sperm function parameters in ejaculated alpaca sperm by flow cytometry. Semen samples were collected from six alpaca males and processed for flow cytometric analysis of sperm viability and plasma membrane integrity using SYBR‐14?PI staining; acrosomal membrane integrity using FITC‐conjugated Pisum Sativum Agglutinin?PI labelling; mitochondrial membrane potential (Δψm) by staining with JC‐1 and DNA Fragmentation Index (DFI) by TUNEL. The results indicate that the mean value for sperm viability was 57 ± 8 %. Spermatozoa with intact acrosome membrane was 87.9 ± 5%, and viable sperm with intact acrosomal membrane was 46.8 ± 9%, high mitochondrial membrane potential (Δψm) was detected in 66.32 ± 9.51% of spermatozoa and mean DFI value was 0.91 ± 0.9%. The DFI was inversely correlated with high Δψm (p = 0.04; r = ?0.41) and with plasma membrane integrity (p = 0.01; r = ?0.47). To our knowledge, this is the first report of the assessment on the same sample of several parameters of sperm function in ejaculated alpaca sperm by flow cytometry.     

Tonometry in adult yellow-footed tortoises (Geochelone denticulata)

Objective To determine intraocular pressure (IOP) in adult yellow‐footed tortoises using applanation tonometry. Animals Fifteen healthy adult captive yellow‐footed tortoises (eight males and seven females). Procedures Intraocular pressures were estimated for tortoises by using an applanation tonometer after topical anesthesia. Body length, measured from nuchal to anal scutes, ranged from 27.5 to 57.2 cm. Five measurements from each eye were obtained by a single observer in an ambient temperature of approximately 30 °C. Results Mean ± SEM IOP of 30 eyes of 15 yellow‐footed tortoises was 14.2 ± 1.2 mmHg. Range of IOP was 6–30 mmHg for tortoises. Significant differences were detected neither between right and left eyes (P = 0.357) of individual tortoises, nor between males and females (P = 0.524). Observer's readability was good (intraclass coefficient = 0.65), and IOP did not change over the ordered five measurements. Conclusions There was no significant difference in IOP between males and females in this specie. Tonometry values for normal eyes may represent a useful diagnostic methodology for recognition and treatment of ocular diseases in reptiles.