Feeding fennel (Foeniculum vulgare) seed as a potential appetite stimulant for Holstein dairy calves: Effects on growth performance and health

This experiment was conducted to determine the effect of increasing dietary doses of fennel seed powder (FSP) on growth performance and health status in calves. Holstein calves (n = 48; 3 d of age; 36.3 ± 1.06 kg BW; mean ± SE) were allocated randomly to diets containing 0 (FSP0), 1.5 (FSP1.5), or 3 g/d (FSP3) FSP in milk (morning feeding; during the first month) and then in the starter feed (top-dressed; from d 31 until weaning on d 71). The calves remained in the trial until d 81. Weight gain and final BW were greater in FSP-supplemented calves compared with control calves. Heart girth and hip width gained more in FSP-supplemented calves compared with control calves. Body weight gain and frame growth were not affected by calf sex. The calves receiving FSP had a lower chance of having elevated rectal temperature (≥39.4°C) and a lower probability of suffering from diarrhea or pneumonia. The chance of having diarrhea, but not pneumonia, was greater in female calves. The chance of medication occurrence for diarrhea and pneumonia was not affected by FSP and calf sex. The FSP3 calves had shorter days with elevated rectal temperature (≥39.4°C) compared with the FSP1.5 (1.2 d; SEM = 0.10) and FSP0 (2.9 d; SEM = 0.10) calves. Days with diarrhea but not its frequency and medication days was shorter (4 d; SEM = 0.10) in the FSP-supplemented calves. Control calves experienced more days with pneumonia compared with calves fed FSP1.5 (3.1 d; SEM = 0.08) and FSP3 (5.4 d; SEM = 0.08). Calves fed FSP3 experienced shorter days (2.3 d; SEM = 0.08) with pneumonia compared with calves fed FSP1.5. Feeding FSP tended to decrease (1.6 d; SEM = 0.10) medication days for pneumonia compared with control group. The duration (2.2 d; SEM = 0.10) and medication days (1.3 d; SEM = 0.15) for diarrhea were higher in female calves compared with the male calves. Compared with the control calves, feeding 3 g/d of FSP may be more beneficial in improving the weight gain and skeletal growth (heart girth and hip width) and in reducing the susceptibility to and duration of diarrhea and pneumonia in dairy calves.

P–060 Dose- dependent mitigation of lead acetate toxicity in males on embryo development in female mice

Study question

Does quercetin (75 or 100 mg/kg BW/day) co-administration with lead acetate to male mice affects embryonic development in female mice?

Summary answer

The low-dose quercetin (75 mg/kg BW/day) ameliorated the adverse effects of lead acetate on mouse embryogenesis.

What is known already

Lead causes male infertility by impacting on endocrine system and spermatogenesis, and may exert undesirable effects on the offspring. The currently approved treatment for lead poisoning is the use of chelating agents, which form an insoluble complex with lead and shield it from biological targets; thus, reducing its toxicity. One of the main mechanisms of lead-induced toxicity is oxidative stress, and it has been reported that natural antioxidants can reduce the heavy metals toxicity. The aim of the present study was to examine the protective effects of quercetin on the toxicity induced by lead acetate on the embryogenesis in mice.

Study design, size, duration

Sexually mature (eight-week-old) NMRI male mice (n = 24) were randomly divided into four groups (n = 6 per group) receiving (i) distilled water (control group); (ii) lead acetate (150 mg/kg BW/day) dissolved in deionized water (LA); (iii) lead acetate (150 mg/kg BW/day) + quercetin (75 mg/kg BW/day) (LQ75); (IV) lead acetate (150 mg/kg BW/day) + quercetin (100 mg/kg BW/day) (LQ100). Treatments were applied daily as oral gavages for one cycle of the seminiferous epithelium (35 days).

Participants/materials, setting, methods

At the end of treatment administration, the males were joined with super-ovulated females, and the retrieved zygotes were cultured for evaluation of the embryo development (at 2-cell, 4-cell, 8-cell, and blastocyst stages), and blastocyst cell number using differential staining (propidium iodide and bisbenzimide). After incubation of capacitated sperm with oocytes, an ultraviolet light microscope was used following 3 min incubation with 25 µg⁄mL bisbenzamide solution for fertilization assessment.

Main results and the role of chance

Lead acetate (LA) treatment of male mice decreased the 2-cell stage compared with the control group (P > 0.05). There was no difference between control and LQ75, and between LA and LQ100. The other stages of embryonic development were not significantly affected by the treatment. Overall, early embryonic development in the control and LQ75 mice were better than LQ100 and LA mice.

The number of cells in the trophectoderm and inner-cell mass were not affected by treatments. However, the total blastocyst cell number in the control was higher than in the other groups; there was no significant difference between LQ100, LQ75 and LA groups. Fertilization rate was not affected by the treatments (P < 0.05).

Quercetin acts as a potent antioxidant at low doses, but at high doses exerts a pro-oxidant action. According to previous reports, higher concentrations of quercetin increased apoptosis and necrosis while decreasing the activities of the antioxidant enzymes. Also, it has been suggested that quercetin might disrupt the endocrine system and interfere with Sertoli cell function and sperm motility.

Limitations, reasons for caution

A limitation of this study is narrow dose selection; more studies are needed to determine the effective dose of quercetin in ameliorating the lead toxicity. There are also side effects of lead-quercetin chelates such as metal redistribution, essential metal loss, accumulation and persistency in intracellular sites, and peroxidation.

Wider implications of the findings: Lead administration adversely impacted on the embryogenesis; on the other hand, paternal quercetin co-administration somewhat ameliorated the adverse effects of lead on mice embryogenesis.

Trial registration number

Not applicable

Reproductive performance, expression of TRAP6 and TGF-β4 genes in utero-vaginal junction mucosa, and indicators of liver function in female Chukar partridge (Alectoris chukar) breeders fed with fish oil and calcitriol during the egg-laying period

Reproductive attributes, expression of TRAP6 and TGF-β mRNA in the mucosa of the utero-vaginal junction (UVJ) of oviduct, and liver function were evaluated in Chukar partridge (Alectoris chukar) breeders subjected to long-term oral administration of fish oil (FO) and/or calcitriol (CT). A total of forty-eight 1.5-year-old laying Chukar partridges and 16 age-matched males (female:male ratio of 3:1) were randomly allocated to four groups (4 replicates of 3 female birds and one male bird each). Breeder females in groups 1, 2, and 3 were orally administered daily with 0.2 mL (0.24 g)/500 g body weight FO, 0.2 mL solution containing 10 μg CT, or their combination (FO + CT) for 42 successive days, respectively. Pure crystalline calcitriol was dissolved in ethanol (30%) prior to administration. The control group (CON), received a similar volume of a 30% solution of ethanol only. Eggs were collected and incubated to evaluate the reproductive performance. Blood samples were taken on days 0, 21, and 42 of the trial for the quantification of serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). On day 43, one bird per replicate was killed by cervical dislocation to assess the expression of TRAP6 and TGF-β genes in the UVJ mucosa. Administration of CT or FO + CT increased the egg production rate, fertility rate, and hatchability rate of the set eggs. Fertility duration and sperm penetration rate were higher in partridges receiving FO and (or) CT, but chick quality, and embryonic mortality were not affected by the treatment effect. Administration of CT or FO + CT decreased the serum ALT and AST levels. Administration of FO or CT was associated with a lower expression of TGF-β mRNA in the UVJ mucosa. Oral administration of FO resulted in a reduction in the expression of TRAP6 in the UVJ mucosa. However, the birds fed with CT or FO + CT recorded a higher mRNA expression for TRAP6. Although the reproductive performance and TRAP6 expression were higher following the feeding of FO or FO + CT, expression of TGF-β was decreased, suggesting plausibly that TGF-β may not have a determinant effect on the reproductive attributes in female Chukar partridges. Further studies are required to understand the mechanisms underlying the effects of TRAP6 and TGF-β on other reproductive criteria in partridges.

The localization and expression of gonadotropin inhibitory hormone in the hypothalamus of turkey hens during the prepubertal, pubertal and postpubertal phases

Gonadotropin inhibitory hormone (GnIH), initially discovered in birds as a hypothalamic neuropeptide, inhibits the synthesis and release of gonadotropins by affecting GnRH neurons and gonadotropes. Therefore, it may be a key neuropeptide in reproduction in birds. The aim of the present study was to investigate the prepubertal, pubertal, and postpubertal localization of GnIH and changes in hypothalamic GnIH expression in British United Turkey hens. In prepubertal, pubertal, and postpubertal periods, the brains of turkey hens (n = 15) were removed after fixation. Sections (30 μm) were prepared from the entire hypothalamus and stained immunohistochemically against GnIH antibody. Gonadotropin inhibitory hormone-immunoreactive neurons were observed in the paraventricular nucleus. These neurons were significantly more abundant in the prepubertal turkeys than pubertal and postpubertal turkeys (P < 0.05). The results suggested that GnIH neurons have an important role in regulating the pubertal events in British United Turkey hens.

Extended transition milk feeding for 3 weeks improves growth performance and reduces the susceptibility to diarrhea in newborn female Holstein calves

Dairy calves may benefit from extending the duration of feeding transition milk (TM; the subsequent two to six milkings after parturition) to enhance performance and health during early life. The objective of this study was to assess the effect of replacing pasteurized waste milk (non-saleable milk containing antibiotic and/or drug residues) with pasteurized TM for 3 weeks on the growth performance and health of dairy calves. A total of 84 healthy newborn female Holstein calves were blocked by birth order and assigned randomly to 4 treatment groups with partial replacement of pasteurized waste milk by TM (second milkings after parturition) at 0 (0 l/day TM + 6 l/day milk), 0.5 (0.5 l/day TM + 5.5 l/day milk), 1 (1 l/day TM + 5 l/day milk), or 2 l (2 l/day TM + 4 l/day milk) for a 21-day period. From day 22 onward, all calves were fed individually with 6 l/day pasteurized waste milk. Calves were weaned on day 60 and monitored until day 90 of the study. Liquid feed DM intake (DMI) was increased with increasing levels of TM (P = 0.001). Starter feed DMI and total DMI (liquid feed DMI + starter feed DMI) were not affected by the treatment effect. Calves were fed 2 l/day TM gained more BW compared with those in the control group during the postweaning and overall periods. The average daily gain tended (P = 0.06) to be higher in calves fed 2 l/day TM compared with calves fed 0 (+ 65 g/day), 0.5 (+ 53 g/day), or 1 (+ 76 g/day) l/day TM during the preweaning period. Daily weight gain was also higher in calves fed 2 l/day TM compared with calves in the control group during the postweaning (+ 137 g/day; P = 0.04) and overall (+89 g/day; P < 0.01) periods, respectively. Calves fed 2 l/day TM had a higher feed efficiency compared with calves in the control group during all studied periods. The calves fed TM2 had a lower chance of having diarrhea compared with other treatment groups. Duration but not the frequency of diarrhea was lower in calves fed TM2 vs TM0 (2.5 vs 4.2days; P = 0.03). In general, partial replacement of waste milk with TM (2 l/day) may be recommended to feed dairy calves at an early stage of life to support a higher growth rate and health benefits.

Extended colostrum feeding for 2 weeks improves growth performance and reduces the susceptibility to diarrhea and pneumonia in neonatal Holstein dairy calves

The objective of this study was to determine the effect of partial replacement of whole milk with colostrum on the growth performance and health status of Holstein dairy calves. Neonatal heifer calves (n = 144; 2 d of age; 39.3 ± 0.82 kg of body weight, BW; mean ± SE) were assigned randomly to 3 groups with partial replacement of pasteurized whole milk with pasteurized colostrum at 0 (C0; 0 kg/d of colostrum + 5 kg/d of whole milk), 350 g (C350; 0.350 kg/d of colostrum + 4.650 kg/d of whole milk), or 700 g (C700; 0.700 kg/d of colostrum + 4.300 kg/d of whole milk) for 14 d; there were no refusals of liquid feed. From d 15 onward, the calves were fed with 5 kg/d of pasteurized whole milk, weaned on d 61, and monitored until d 81 of life. Throughout the study, the calves had free access to fresh clean water and calf starter. Partial replacement of whole milk with colostrum increased liquid feed dry matter intake (DMI) but decreased milk DMI; however, intakes of starter DMI, total DMI, metabolizable energy, crude protein, and ether extract were not affected by treatments. Overall, the C700 calves recorded greater weaning weight, final BW, heart girth change, feed efficiency, and average daily gain (ADG). The calves fed milk had a higher chance of having rectal temperature ≥39.4°C and general appearance score ≥2 compared with those receiving colostrum in their milk. Diarrhea was more prevalent in C0 versus C700 calves. The occurrence of pneumonia tended to be higher in milk-fed calves compared with C350 and C700 animals. Colostrum feeding resulted in fewer days with a rectal temperature ≥39.4°C, general appearance ≥2, diarrhea, and pneumonia. We computed Cliff's delta (effect sizes) of the extended colostrum feeding (C350 vs. C0, C700 vs. C0, and C700 vs. C350) on starter and milk DMI, ADG, BW, and feed efficiency. In C350 calves, the effect sizes (Cliff's delta) for milk DMI, ADG, BW, and feed efficiency were positive and small, but negative in C700 calves. Compared with C350 treatment, C700 treatment resulted in greater final BW with moderate effect size. Positive and moderate effects of feeding colostrum (C700 vs. C0) were observed on postweaning ADG and final BW. The findings showed that the inclusion of 700 g of colostrum in 5 kg of milk may be beneficial to the growth and health of dairy calves.

The long-term oral administration of thyroxine: effects on blood hematological and biochemical features in broiler breeder hens

Published data on the beneficial effect of short-term administration of thyroxine (T₄) in broiler breeder hens to reduce the ascites incidence in their progeny chicks raises the question as to what extent might the long-term maternal administration of T₄ affect the blood hematological and biochemical attributes in breeder hens. A total of 70 broiler breeder hens (47-wk-old) were randomly allotted to control or thyroxine treated (T₄) groups. Pure T₄ (0.3 mg/bird per day) was orally administered to T₄ birds for 14 successive weeks, whereas the control group received the drinking water only. Blood samples were obtained from the brachial vein prior to the initiation of the trial as well as weeks 50, 53, 55, 57, 59, and 61 of age. Body weight was decreased but egg production was not affected by T₄ treatment. Plasma concentration of T₄, but not triiodothyronine (T₃), was increased in T₄-treated hens (P < 0.05). The total number of leukocytes and erythrocytes were also higher in T₄ birds. A significant effect of time was observed for erythrocyte number and plasma cholesterol concentration (P < 0.05). The long-term administration of T₄ did not affect the concentrations of serum calcium and plasma total protein, albumin, globulin, cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, very low density lipoprotein, alanine amino transferase, and aspartate amino transferase (P > 0.05). However, serum concentrations of phosphorus, glucose, and alkaline phosphatase were higher in T₄ hens as compared to their control counterparts. In spite of differences in circulatory concentrations of a number of traits between the experimental groups, the recorded values were within their reference ranges. Therefore, the administration of T₄ for an extended period of time had no apparent adverse effect on the clinical profile in subjected hens, which may practically support the implementation of this preventative treatment as an approach to decrease the ascites incidence; however, a lower incidence rate in the progeny chicks produced from hens receiving T₄ for long-term periods of time remains to be elucidated.

Effects in broiler hens of genetic lines differing in fertility, biotin supplementation, and age on relative abundance of oviductal transforming growth factor-β and carbonic anhydrase mRNA transcripts

There was evaluation of effects of biotin administration on oviductal abundance of transforming growth factor-β (TGF-β) and carbonic anhydrase (CA) mRNA transcript in younger and older broiler hens of relatively lesser and greater fertility lines. Additionally, effects of biotin supplementation on attenuation of age-related subfertility were evaluated. Hens from the relatively greater (Line D, n = 60) and lesser (Line B, n = 60) fertility rate line were randomly assigned to three treatment groups. Biotin was not or was administered in drinking water from 30 to 33 (younger age) and 53 to 56 (older age) wk of age to have access to no biotin (T₀), or 0.3 (T₁), or 0.45 (T₂) mg/L of biotin. There was assessment the relative oviductal abundances of TGF-β and CA mRNA transcript abundances. Supplemental biotin and age had no effect on the relative abundance of oviductal TGF-β mRNA transcript in hens of Line D. There, however, was a ten-fold greater abundance of TGF-β in hens of the T₀ group of Line B compared with Line D. Relative abundance of TGF-β mRNA transcript was greater in younger hens of Line B; however, biotin supplementation of older hens of the T₂ group of Line B resulted in a similar TGF-β abundance to that of younger hens. Inconstant with the TGF-β abundance, CA abundance in hens of Line B was not affected by supplemental biotin or bird age. Overall, differences in TGF-β or CA abundances did not affect fertility of broiler hens.

Sperm characteristics of Chukar partridge (Alectoris chukar) breeders as affected by the addition of calcitriol to the semen extender

This study was carried out to determine the effect of supplementing the semen extender with calcitriol on in vitro sperm characteristics in Chukar partridges. A total of 60 male Chukar partridges were habituated for semen collection by abdominal massage. Pooled ejaculates from several males were extended (1 to 5 v/v ratio) in the Sexton's diluent containing 0, 24, 48, 96, or 192 μg calcitriol/mL. These concentrations represented 0-, 2-, 4-, 8-, and 16-fold levels of the mean seminal calcitriol concentration, respectively. A total of 12 subsamples from each treatment group were kept at 4 to 5°C or 19 to 24°C for 4, 24, or 48 h. The percentages of motile sperm, live sperm, abnormal sperm, incidence of hypoosmotic swelling (HOS), and thiobarbituric acid reactive species (TBARS) concentrations were determined. The data were analyzed by the xtmixed procedure of STATA software. The percentages of motile sperm, live sperm, abnormal sperm, and seminal TBARS were affected by calcitriol (P < 0.05). There was no effect of treatments on HOS (P > 0.05). There was an interaction effect between calcitriol, storage time, and storage temperature on sperm motility, sperm viability, and seminal TBARS. Supplementation of the diluent with 96 μg calcitriol/mL resulted in the highest sperm motility at 4°C. Also, the same treatment group recorded the highest sperm viability and lowest seminal TBARS at 19 to 24°C. Supplementing the diluent with calcitriol had beneficial effects on spermatozoa; however, the fertility rate of spermatozoa extended in calcitriol-supplemented diluent needs to be determined before the procedure can be recommended for use in artificial insemination programs.

Changes in broiler breeder hen's immunity by zinc oxide and phytase

BACKGROUND

The immune response of aged broiler breeder hens is influenced by many factors including obesity and aged lymphatic organs, but may improve by increasing the bioavailability of various nutrients such as zinc (Zn). Dietary supplementation of phytase can improve Zn availability in senescent broiler breeder hens.

AIMS

The aim of this study was to investigate the effect of supplementary zinc oxide (ZnO) and phytase in a maize-soybean meal-based diet on immune responses of broiler breeder hens.

METHODS

In a 2 × 4 factorial arrangement, a total of 128 hens were randomly assigned into eight groups. The birds received two levels of phytase (0 or 300 U/kg diet) and four levels of ZnO (30, 60, 90, and 120 mg/kg diet) for 13 successive wk (59-72 wk of age).

RESULTS

Results showed that phytase supplementation significantly increased immunoglobulin M (IgM), cutaneous basophil hypersensitivity (CBH) responses, total number of leukocytes, percentage of lymphocytes, and heterophil to lymphocyte ratios. The percentage of basophils and monocytes, however, decreased with phytase supplementation. Supplementation of ZnO increased anti-sheep red blood cells (SRBC) antibody titer, IgM, CBH responses, the total number of leukocytes, and the percentage of lymphocytes. Dietary supplementation of ZnO decreased the percentage of heterophil, and heterophil to lymphocyte ratio. A significant interaction effect of phytase and ZnO was found on the total number of leukocytes and percentage of lymphocytes.

CONCLUSION

Dietary supplementation of ZnO (90 mg/kg diet) and phytase had some positive effects on improving immune responses in broiler breeder hens.

Introducing a combined Leishman-Giemsa stain as a new staining technique for avian blood smears

BACKGROUND

The use of conventional stains including Giemsa, Wright and Leishman have become an essential tool for differential diagnosis of cells in peripheral blood.

AIMS

The aim of the study was to develop a new combination of Leishman-Giemsa (L&G) stain for avian blood smears and to compare its efficacy with conventional staining methods.

METHODS

Three sets of peripheral blood smears, one smear for L&G stain and two other smears for Leishman and Giemsa stains, created from 50 broiler chickens blood samples. All the three sets of slides were blind screened by two expert clinical pathologists and scored based on the staining characteristics (4 parameters) such as nuclear features of red blood cell (RBC) and white blood cell (WBC), cytoplasmic features and cytoplasmic granularity of WBC. The average grading score assigned by two experts for each staining method were compared.

RESULTS

The average grading score of two conventional Leishman and Giemsa staining methods were significantly lower (P<0.001) than new L&G staining method in avian nuclear features of the RBC and WBC. The L&G stain gave a better clarity of nuclear features of avian RBC and WBC. The new L&G staining technique created significant differences (P<0.001) in cytoplasmic features of avian WBC compared to the other two methods.

CONCLUSIONS

For the first time, the results of the present study showed that the avian blood cells are more desirable stained with a new combination of L&G stain. In addition, it gives a better nuclear and cytoplasmic differential staining than the conventional Giemsa and Leishman stains when used alone.

Histomorphometrical changes of oviduct during the long-term exposure of breeder hens to extra thyroxine

In this research a 100 day long treatment period was considered to unmask the probable adverse effects of long-term induced hyperthyroidism on histomorphometrical attributes of the oviduct in broiler breeder hens. A total of seventy 47-week-old Cobb 500 breeder hens were randomly allotted to two treatment groups (5 replicates of 7 hens each). Thyroxine (T4) was orally administered to the hyperthyroid group (0.3 mg/bird/d) for 100 consecutive days; whereas the control group received drinking water only throughout the trial. At 64 weeks of age, 2 birds per replicate were killed by cervical dislocation and their oviducts were removed. For histomorphometrical observations, segments were taken from five different regions. After tissue preparation and staining with haematoxylin and eosin, histological layers were evaluated using light microscopy. The assessment of histomorphometrical characteristics of oviduct showed the height of mucosal folds in the magnum, thickness of mucosal folds of the magnum and uterus, thickness of tunica muscularis in the magnum and vagina, epithelial thickness of the isthmus and vagina, and uterine tubular glands percentage were decreased in the hyperthyroid birds compared with the control counterparts. The results showed long-term induced hyperthyroidism was associated with a decrease in a number of histomorphometrical traits in different regions of the oviduct. Some studies should be done to clarify to what extent the long-term maternal hyperthyroidism might affect the egg production, fertility rate, duration of fertility, and sperm penetration rate to make a final decision on exploitation of this preventative treatment to diminish the ascites incidence in progeny chicks.

Is immunosuppression, induced by neonatal thymectomy, compatible with poor reproductive performance in adult male rats?

With increasing knowledge that the immune system has a major impact on reproductive ‎health, the potential for cells arising in organs such as the thymus to alleviate oxidative stress ‎has been revealed. This study addresses the impact of neonatal thymectomy on male ‎reproductive function in pubertal and adult animals. Neonatal Sprague Dawley rats were allotted to four treatments consisting of fully thymectomized, partially thymectomized, intact, and sham-operated rats. Half of the rats in each treatment were sacrificed at 40 and the other half at 80 days of age. Testicular volume, ventral prostate and spleen weight, several sperm attributes (concentration, motility, livability, membrane integrity, sperm penetration into mucus, total antioxidant capacity, mitochondrial dehydrogenase activity), plasma superoxide dismutase, glutathione, and testosterone level as well as fertility decreased in thymectomized rats. Adrenal gland weight, sperm malondialdehyde level, indices of oxidative stress, sperm abnormality, testicular and sperm lipid peroxidation, protein carbonylation, and sperm reactive oxygen species generation increased in thymectomized rats. In thymectomized rats, the testes contained high levels of malondialdehyde but low levels of glutathione and ferric-reducing antioxidant power. Epididymal sperm reactive oxygen species, blood lipid peroxidation, and oxidative stress indices ‎‎in blood and spermatozoa were highest in fully thymectomized, intermediate ‎in partially thymectomized, and lowest in both pubertal and mature control rats. Blood levels of superoxide dismutase, lipid peroxidation indices, and ‎testosterone, and mitochondrial adenosine triphosphate and ‎dehydrogenase activities in epididymal spermatozoa were lowest in fully thymectomized, ‎intermediate in partially thymectomized, and highest in both pubertal and mature control rats.‎ The data indicated that increased oxidative stress and mitochondrial dysfunction might play a role in the mechanism of immunosuppression-induced testicular and sperm abnormalities.

Effect of dietary fish oil with or without vitamin E supplementation on fresh and cryopreserved ovine sperm

This study was carried out to determine whether dietary fish oil (FO) with or without vitamin E (VE) supplementation would have a beneficial effect on characteristics of fresh and cryopreserved ovine sperm. Sixteen rams were allotted to four groups and fed one of the four diets: control diet (CON; without FO and VE supplementation), VE diet supplying 200 IU VE/day.ram, FO diet containing 2.5% (dry matter basis) FO, and OVE diet containing FO and VE. Semen samples were collected at Weeks 7, 9 and 11 for evaluation of seminal quality. Frozen samples from Weeks 9 and 11 were subjected to computer-assisted semen analysis (CASA). Seminal volume, percentage of sperm with normal morphology and intact acrosome and seminal concentration of malondialdehyde were increased in FO rams (P < 0.05). In VE rams, semen volume and percentage of morphologically normal sperm were higher compared with CON rams; however, in OVE rams these attributes were not different from those in CON rams. Other traits in fresh semen were not affected by the diet. Fish oil alone negatively affected the sperm viability, but not motility, of the frozen–thawed semen; however, simultaneous supplementation with FO and VE resulted in increased percentage of morphologically normal sperm, motility, and viability. The percentages of CASA type A (showing rapid progressive motility) and type B (showing medium progressive motility) sperm were higher in OVE compared with other groups. Vitamin E supplementation decreased the beat-cross frequency values compared with other groups. Other CASA parameters were not affected by the diets. In conclusion, dietary FO and VE in the breeding season of ram, generally, do not cause significant changes in fresh sperm quality but, for cryopreservation of sperm, supplementation of the diet with an antioxidant such as VE may be beneficial when polyunsaturated fatty acids are added to the diet.

Periodical low eggshell temperatures during incubation and post hatch dietary arginine supplementation: Effects on performance and cold tolerance acquisition in broilers

An experiment was conducted to evaluate the effects of a periodically low eggshell temperature exposure during incubation and dietary supplementation of arginine on performance, ascites incidence, and cold tolerance acquisition in broilers. A total of 2,400 hatching eggs were randomly assigned to 2 treatment groups (16 replicates of 75 eggs per treatment). The eggs were incubated at a constant eggshell temperature (EST) of 37.8ºC throughout the incubation period (CON) or were periodically exposed to 15°C for one hour on days 11, 13, 15, and 17 of incubation and the EST was measured (periodical low EST; PLE). After hatching, 240 one-day-old male broiler chicks from both treatment groups were reared for 42 d with or without dietary arginine supplementation in a completely randomized design with a 2 × 2 factorial arrangement. In order to induce ascites, all chicks were exposed to a 15°C room temperature from 14 d onwards. Results showed that second grade chicks and yolk sac weight were decreased, and final body weight was increased in the PLE group. Ascites mortality rate was decreased only in the PLE group and dietary arginine supplementation had no apparent effect. In the PLE group, the packed cell volume (PCV) percentage and red blood cell (RBC) count were decreased. In conclusion, the results showed that the PLE treatment during incubation was associated with improved hatchability, chick quality, and productive performance of broilers and decreased ascites incidence during post hatch cold exposure. Dietary arginine supplementation had no beneficial effects in cold exposed broilers.

Effect of thymol and carvacrol on nutrient digestibility in rams fed high or low concentrate diets

Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (P<0.05), but within each level of dietary concentrate no significant differences were observed for these measurements. Overall, ruminal ammonia concentration was higher (P<0.05) in both HCD and LCD lambs receiving 0.3 mg thymol per kg diet. Supplementation of carvacrol had no significant effect on nutrient digestibility. The main effect of carvacrol on ruminal ammonia levels and NB was significant, but within each level of dietary concentrate no significant differences were observed in ammonia levels and NB. Inclusion of 0.3 g/kg diet DM of carvacrol or thyme was more effective than 0.6 g/kg diet DM in terms of NB but neither dose affected nutrient digestibility. Future research should determine the long-term effects of essential oils on digestibility and performance in sheep, before recommendation can be made for their use under practical husbandry conditions.

Flow cytometric and microscopic evaluation of post-thawed ram semen cryopreserved in chemically defined home-made or commercial extenders

The present study was designed to determine the effect of three different extenders on ram sperm quality during a freeze–thawing procedure using flow cytometric and microscopic evaluations. Several in vitro qualitative analyses of post-thawed sperm parameters including motility and velocity parameters, plasma membrane functionality, total abnormality, capacitation status, acrosome integrity, mitochondrial activity and apoptosis features were considered. In the breeding season, seven ejaculates from each Zandi ram were collected routinely twice a week. Following semen collection, samples were pooled and equally divided into three aliquots. Each aliquot was diluted and frozen with one of the following extenders: (1) Tris-based extender containing 1.5% (w/v) soybean lecithin (TSL), as a chemically defined extender, (2) Bioxcell, a commercial soybean lecithin-based extender, and (3) Tris-based extender containing 20% (v/v) egg yolk (TEY). The results of the present study indicated no differences in total [TSL (55.8 ± 2.02%) vs TEY (50.2 ± 2.02%; P < 0.05)] and progressive motility of spermatozoa [TSL (26.2 ± 1.36%) vs Bioxcell (22.4 ± 1.36%; P < 0.05)]. Semen freezing by means of TSL resulted in a higher percentage of live spermatozoa (39.42 ± 1.81%) compared with TEY (29.17 ± 1.81%; P < 0.05), and a higher percentage of functional plasma membrane (50.8 ± 192%) compared with TEY (44 ± 1.92%) and Bioxcell (38.8 ± 1.92%; P < 0.05). The effect of extenders on sperm capacitation status showed that the percentage of post-thawed capacitated spermatozoa was higher in TEY (61.9 ± 1.48%) compared with that in TSL (56.6 ± 1.48%; P < 0.05). The evaluation of post-thawed spermatozoa indicated that the percentage of live spermatozoa with active mitochondria was higher in TSL (53.05 ± 2.31%) compared with Bioxcell (45.92 ± 2.31; P < 0.05) and the percentage of intact acrosome spermatozoa was higher in TSL (84.55 ± 2.51%) compared with TEY (74.91 ± 2.51%; P < 0.05). The use of TSL and Bioxcell extenders reduced the percentage of apoptotic spermatozoa (40.82 ± 2.07% and 42.22 ± 2.07%, respectively), compared with TEY (51.34 ± 2.07%; P < 0.05). Post-thawing dead spermatozoa were increased when semen was frozen by Bioxcell (25.69 ± 1.28%). The results of this study showed that TSL extender may provide stabile milieu and conditions for ram sperm cryopreservation compared with Bioxcell and TEY extenders. Whether TSL extender can improve the artificial insemination results remains, however, an open question.

Reproductive performance and oviductal expression of avidin and avidin-related protein-2 in young and old broiler breeder hens orally exposed to supplementary biotin

Published data on the probable involvement of avidin and avidin-related protein-2 (AVR2) in sustaining sperm viability in sperm storage tubules in 38-wk-old turkeys, and the high affinity of avidin or its analogs to biotin suggest that supplementary biotin may increase oviductal avidin and AVR2 expression, thereby attenuating the adverse effect of aging on hen reproductive performance. Broiler breeder hens (n = 120) were randomly assigned to receive 0 (T0), 0.30 (T1), or 0.45 (T2) mg of biotin/L of drinking water from 30 to 33 (young) and 53 to 56 (old) wk of age, and artificially inseminated to determine their reproductive performance. At the end of each period of biotin administration, 8 hens from each treatment group were killed for RNA extraction from the uterovaginal junction. Egg production was lower in the old hens (44%) compared with the young ones (82%), and biotin supplementation increased egg production only in the latter. Administering supplementary biotin to young hens increased their oviductal expression of AVR2, which was much higher in the old hens (1.0 and 4.6 for young and old groups, respectively). Fertility rate was not different between young and old hens, and was increased (4.4%) at the higher level of biotin supplementation. Hatchability and hatchling quality were not affected by biotin supplementation. Embryonic mortality between 17 to 21 d of incubation was higher in young (5.2%) compared with old (1.4%) birds. Egg fertility rate showed a moderate correlation (P < 0.05) with avidin (r = 0.59) and AVR2 (r = 0.55) expression in the young-age group, and very low correlations in old-age group (0.04 and 0.17). Regardless of the hen's age, the correlation coefficient of hatchability with avidin or AVR2 expression was very low (-0.16 and 0.18). Overall, the effect of biotin supplementation on AVR2 expression, and the relationship between biotin administration and oviductal expression of avidin and AVR2 was dependent on the hen's age, being higher in the young hens.

Improvements in semen quality, sperm fatty acids, and reproductive performance in aged Cobb 500 breeder roosters fed diets containing dried ginger rhizomes (Zingiber officinale)

Exposure to high levels of polyunsaturated fatty acid predisposes spermatozoa to lipid peroxidation, resulting in their decreased fertility. Ginger powder (GP), which is high in antioxidative compounds, was fed to aged breeder roosters to improve their reproductive performance. Seventy-five 52-wk-old Cobb 500 breeder roosters randomly received either 0 (GP0), 15 (GP15), or 30 (GP30) g of GP/kg of diet for 14 consecutive wk, during which time their seminal characteristics were evaluated every 2 wk. At the end of the trial, semen samples were tested for determination of sperm fatty acid (FA) concentration and seminal plasma total antioxidant capacity. Furthermore, sperm penetration was assayed, and using 225 artificially inseminated hens, fertility and hatchability rates were determined. Dietary GP improved sperm forward motility, live sperm percentage, and sperm plasma membrane integrity. These were associated with a decrease in the percentage of abnormal sperm. The seminal TBA reactive species concentration was lower in birds belonging to the GP30 treatment in comparison with those in the GP15 and GP0 treatments. The feeding of GP resulted in overall decreases and increases in sperm saturated and unsaturated FA, respectively. The n-6:n-3 FA ratio of sperm was decreased in the GP30 group in comparison with controls. The highest levels of sperm C20:4(n-6) and C22:6(n-3) FA were recorded in the GP15 and GP30 treatments, respectively. A higher percentage of sperm C22:4(n-6) FA was found in GP-fed roosters. Seminal plasma total antioxidant capacity was considerably improved by the GP15 and GP30 treatments. Further, a higher number of perivitelline membrane sperm penetration holes was recorded for the GP30 treatment in comparison with the GP15 and GP0 treatments. Interestingly, although hatchability, chick quality, and embryonic mortality were not affected by dietary treatment, fertility rate was improved by the feeding of GP. In conclusion, dietary GP improved most of the seminal characteristics evaluated in aged roosters of this study, suggesting that it has potential for use in attenuating age-related subfertility in senescent male commercial broiler breeders.

Differential expression of RFamide-related peptide, a mammalian gonadotrophin-inhibitory hormone orthologue, and kisspeptin in the hypothalamus of Abadeh ecotype does during breeding and anoestrous seasons

Gonadotrophin-inhibitory hormone (GnIH) is a novel hypothalamic neuropeptide that was discovered in birds as an inhibitory factor for gonadotrophin release. RFamide-related peptide (RFRP) is a mammalian GnIH orthologue that inhibits gonadotrophin synthesis and release in mammals through actions on gonadotrophin-releasing hormone (GnRH) neurones and gonadotrophs, mediated via the GnIH receptor (GnIH-R), GPR147. On the other hand, hypothalamic kisspeptin provokes the release of GnRH from the hypothalamus. The present study aimed to compare the expression of RFRP in the dorsomedial hypothalamus and paraventricular nucleus (DMH/PVN) and that of kisspeptin in the arcuate nucleus (ARC) of the female goat hypothalamus during anoestrous and breeding seasons. Mature female Abadeh does were used during anoestrus, as well as the follicular and luteal phases of the cycle. The number of RFRP-immunoreactive (-IR) neurones in the follicular phase was lower than in the luteal and anoestrous stages. Irrespective of the ovarian stage, the number of RFRP-IR neurones in the rostral and middle regions of the DMH/PVN was higher than in the caudal region. By contrast, the number of kisspeptin-IR neurones in the follicular stage was greater than in the luteal stage and during the anoestrous stage. Irrespective of the stage of the ovarian cycle, the number of kisspeptin-IR neurones in the caudal region of the ARC was greater than in the middle and rostral regions. In conclusion, RFRP-IR cells were more abundant in the rostral region of the DMH/PVN nuclei of the hypothalamus, with a greater number being found during the luteal and anoestrous stages compared to the follicular stage. On the other hand, kisspeptin-IR neurones were more abundant in the caudal part of the ARC, with a greater number recorded in the follicular stage compared to the luteal and anoestrous stages.

Growth performance and intestinal morphology in broiler chickens produced from hyperthyroid breeder hens

An association between induced maternal hyperthyroidism and a decreased incidence of cold-induced ascites in broiler chickens has been reported recently. There are also reports suggesting that thyroid hormones have an effect on intestine, a high oxygen-demanding organ. The present study aimed to determine whether the ascites-attenuating effect of maternal hyperthyroidism is associated with morphological changes in intestine and with probable adverse effects on growth performance in progeny chicks. Eighty-eight broiler breeder hens were allotted to control or hyperthyroid [HYPER; thyroxine-treated] groups, and artificially inseminated. Hatching eggs (n = 924) were incubated and day-old male chicks (n = 288) were reared for 42 days under standard or low ambient temperature. Plasma thyroxine was higher in the HYPER hens and their embryos at internal pipping. Maternal hyperthyroidism did not adversely affect the feed : gain ratio and carcass weight, whereas cold stress impaired them. A higher relative weight was found at 42 days of age for all intestinal regions at low ambient temperature. The duodenal and jejunal crypt depths (CD) were lower in HYPER group at 7 days of age. Cold exposure decreased the duodenal and jejunal villus height and CD, and increased the ileal goblet cell number at 21 days. On Day 42, higher values were recorded for CD, goblet cell number, and epithelial thickness of different intestinal regions in cold-exposed birds. In conclusion, growth performance was not adversely influenced by maternal hyperthyroidism and its minimal early effect on intestinal morphology does not appear to be the underlying mechanism for decreased incidence of ascites in broilers.

Seminal characteristics, sperm fatty acids, and blood biochemical attributes in breeder roosters orally administered with sage (Salvia officinalis) extract

Seminal characteristics and blood biochemical attributes were studied in breeder roosters orally administered with sage extract (SG), an herbal extract well known to have potent antioxidant activities. Sixty roosters (34 weeks old) were randomly allotted to five treatment groups to receive no SG, or orally administered with 110, 210, 320, or 420 mg SG/kg liveweight for 8 weeks. Semen samples were evaluated weekly. Blood samples were taken fortnightly and a total of 21 biochemical indices were measured to unmask the effects of SG (especially the adverse ones) on the clinical profile. Excluding the sperm concentration and seminal content of thiobarbituric acid reactive substances (sperm membrane lipid peroxidation index), other seminal traits exhibited one of the linear, quadratic, or cubic responses to the various levels of SG. The most improvements in total live sperm number and sperm membrane integrity (as determined by the hypoosmotic swelling test) were observed in birds receiving 210 and 320 mg SG/kg liveweight, respectively. Serum testosterone level was generally higher (cubically, P = 0.015), but serum copper was lower (linearly, P = 0.014) in SG-administered birds. Birds receiving 320 and 420 mg SG showed a decreased content of C18 : 2(n-6) in sperm plasma membrane. Other biochemical attributes or sperm fatty acids were not affected. It seems that most improvement in the seminal characteristics could be achieved 5–6 weeks following the administration of 210 and 320 mg SG/kg liveweight without any apparent adverse effect on the blood biochemical indices. The improvements, however, could not be attributed to the antioxidative effect of SG. Although it is hypothesised that an increased serum testosterone might have been involved, the underlying mechanism(s) remain(s) to be clarified.

Dietary inclusion of dried tomato pomace improves the seminal characteristics in Iranian native roosters

Because of a paucity of information on the effect of tomato pomace in male chickens, a study was undertaken to determine the influence of dietary inclusion of dried tomato pomace (DTP) on seminal characteristics in Iranian native breeder roosters. Fifty-four roosters (24 wk old) were randomly allotted to 3 treatment groups and received either a basal diet without DTP (T(0)), or a diet containing 15% (T(15)) or 30% (T(30)) DTP for an 8-wk-long experimental period. Semen samples were obtained weekly by abdominal massage to evaluate the seminal characteristics. Dietary inclusion of DTP increased sperm concentration, accompanied by a decreased seminal volume (P ≤ 0.05). The percentage of live sperm in ejaculate was increased in T(15) and T(30) groups, but sperm forward motility was not affected by DTP inclusion. A decreased percentage of abnormal sperm and improved membrane integrity (as determined by the hypoosmotic swelling test) were observed in T(15) and T(30) groups. Lower concentration of thiobarbituric acid reactive substances (as an index of sperm membrane lipid peroxidation) was recorded in roosters fed DTP. A diet × time (wk) interaction was also found for most of seminal characteristics, except for the sperm forward motility (P ≤ 0.05). The results indicated that dietary inclusion of DTP up to 30% improved seminal quality attributes within 4 to 5 wk in roosters; however, the underlying mechanism(s) warrants further study.

Genetic relationship of conformation traits with average somatic cell score at 150 and 305 days in milk in Holstein cows of Iran

Genetic, environmental, and phenotypic correlations among average somatic cell score (SCS) at different stages of lactation and conformation traits were estimated. Data consisted of the lactational average of SCS at 150 (SCS(150)) and 305 (SCS(305)) d in milk and 19 conformation traits recorded on 57,154 primiparous Holstein cows, that calved from 1996 to 2009 in 119 herds in Iran. Variance components were estimated using the restricted maximum likelihood procedure based on multiple-trait animal models. Udder depth (-0.32), fore udder attachment (-0.22), and udder width (0.34) showed moderate genetic correlation with SCS(150). Heart girth (0.17), body depth (0.14), chest width (0.26), and angularity (0.19), showed modest genetic correlation with SCS(150). The estimated heritabilities for SCS(150) and SCS(305) were 0.06 and 0.08, respectively. The heritability of the conformation traits ranged from 0.09 to 0.29. Genetic and environmental correlations between SCS(150) and SCS(305) were very high (means ± SE; 0.99±0.01 and 0.89±0.01, respectively), which indicates that recording SCS over a shorter period of lactation is an alternative approach for involving many herds in SCS data collection. The low heritability of SCS indicated that indirect selection for some of udder and body traits might be helpful to reduce the SCS. Additionally, selection for udder traits may help reduce SCS in developing countries where SCS data are sparsely recorded.

Appropriate reference gene selection for real-time PCR data normalization during rat mesenchymal stem cell differentiation

Reverse transcription quantitative PCR (RT&mdash;qPCR) is one of the best methods for the study of mesenchymal stem cell (MSC) differentiation by gene expression analysis. This technique needs appropriate reference or housekeeping genes (HKGs) to normalize the expression of the genes of interest. In the present study the expression stability of six widely used HKGs including Actb, Btub, Hprt, B2m, Gusb and Tfrc was investigated during rat MSC differentiation into osteocytes, adipocytes and chondrocytes lineages using geNorm and NormFinder software. RT&mdash;qPCR data analyzed by geNorm revealed the different sets of suitable reference genes for each cell type. NormFinder also showed similar results. Analysis of the combined data of MSCs with each differentiated cell type revealed the considerable shift in expression of some reference genes during differentiation; for example Gusb and B2m were among the least stable genes in MSCs but the most stable in chondrocytes. Normalization of specific genes for each lineage by different reference genes showed considerable difference in their expression fold change. In conclusion, for the appropriate analysis of gene expression during rat MSC differentiation and also for monitoring differentiation procedures, it is better to consider precisely the reference gene stability and select suitable reference genes for each purpose.