Nutrient digestion, ruminal fermentation and performance of dairy cows fed pomegranate peel extract

An experiment was carried out to determine the effect of pomegranate peel extract (PPE) on nutrient digestion, ruminal fermentation characteristics, protozoal population and performance of dairy cows. Four Holstein cows were used in a 4×4 Latin square design with 28-d periods and 4 treatments: PPE0 (no extract), PPE400 (400 ml PPE/cow/d), PPE800 (800 ml PPE/cow/d) and PPE1200 (1200 ml PPE/cow/d). Intake of dry matter, milk yield, and digestibility of dry matter, organic matter, crude protein, neutral detergent fiber and acid detergent fiber were measured. Ruminal fermentation characteristics such as ruminal pH, concentration of NH3–N, concentration of VFA, molar proportions of individual VFA, protozoa population and microbial N were also measured. Milk production, 4% FCM yield, milk fat and protein yield (kg/d), and milk efficiency were increased by inclusion of PPE800 in the diet. Percent of milk fat, true protein, and lactose were not affected by PPE supplementation. However, inclusion of PPE decreased NH3–N, total protozoal population, genus Isotricha and Entodinium, but increased microbial N production (g/d). Concentrations of total VFA and molar proportions of individual VFA were not affected by inclusion of PPE in the diet. The results suggested that PPE supplementation has reduced protozoa population, NH3-Nconcentration, and increased microbial protein and milk yield and quality

Nitrogen balance,blood metabolites and milk fatty acid composition of dairy cows fed pomegranate-peel extract

An experiment was carried out to determine the effect of pomegranate peel extract (PPE) on nitrogen balance, blood parameters and the milk fatty acid profile of dairy cows. Four Holstein cows were used in a 4×4 Latin square design with 28-d periods and 4 treatments: PPE0 (no extract), PPE400 (400 ml PPE/cow/d), PPE800 (800 ml PPE/cow/d) and PPE1200 (1200 ml PE/cow/d). Nitrogen balance, blood parameters and the milk fatty acid profile were measured. Determination of secondary metabolites showed its high content of aqueous fraction, total phenolics and total tannin with reasonable content of saponins. Outputs of N in milk were quadratically increased (P=0.044) by inclusion of PPE at 400 and 800 ml PPE/cow/d in the diet. Blood cholesterol (quadratic effect, P=0.043), blood urea nitrogen (linear effect, P=0.047) and milk urea nitrogen (quadratic effect, P=0.0008) concentrations decreased with adding PPE. Supplementation with PPE quadratically lowered total saturated fatty acid (P=0.005), proportions of C12:0 (linear effect=0.040), C16:1c9 (quadratic effect, P=0.011), C18:0 (linear effect, P=0.083, quadratic effect, P=0.011) and ω6/ω3 (quadratic effect, P=0.007). Amount of C18:3c (n-3) (linear effect, P=0.046), DHA (C22:6) (quadratic effect, P=0.009) and EPA (C20:5) (quadratic effect, P=0.012) were increased by inclusion of PPE. Adding PPE lowered blood cholesterol, blood urea nitrogen and milk urea nitrogen. Milk from cows fed PE had significantly lower total saturated fatty acid, desirable ω6/ω3 ratio and higher content of EPA and DHA

The effects of letrozole-induced maternal hyperandrogenism on sexual behaviors, testicular histology, and serum biochemical traits in male offspring rats: An experimental study

Background: Intrauterine endocrine abnormalities have profound effects on the development of physiological disorders. Objective: This study aimed to assess the effects of in utero exposure to letrozole (an aromatase inhibitor) and its late consequences on the reproductive and metabolic performance of an adult male offspring. Materials and Methods: 15 pregnant Sprague-Dawley rats (8 wk, 155 gr) were randomly assigned into 5 experimental groups (n = 3/each) and orally received either letrozole at doses of 0.25, 0.75, 1.00, and 1.25 mg/kg body weight (BW) or vehicle (control) on the gestation days of 16, 17, and 18. Pregnancy outcome, sexual behaviors on postnatal day 60, serum biochemical features, and the histopathology of testes were assessed in male offspring. Results: Compared to control group, delayed labor (21.83 vs. 24.25, p < 0.0001) and reduced litter size (n = 12.25 vs. n = 2, p < 0.0001) were recorded in 1.25 mg/kg BW group. A reduction in high-density lipoprotein level and the elevation of testes weight, BW gain, anogenital distance, as well as the serum concentrations of testosterone, triglycerides, cholesterol, and glucose were observed in 1.25 mg/kg BW (p < 0.0001) and 1.00 mg/kg BW (p < 0.0001) groups in comparison to control. A larger number of anogenital female sniffing, pursuit, and mounting behaviors were also observed in 1.25 mg/kg BW group in comparison to control (p < 0.0001). Severe testicular defects including necrosis and disruption of the epithelium of seminiferous tubules, sloughing of epithelial cells, and spermatogenesis arrest were observed in letrozole-treated groups, in a dose-dependent manner. Conclusion: Maternal exposure to letrozole can adversely affect the reproductive and metabolic performance of male offspring rats, suggesting an incomplete sex differentiation. Key words: Androgens, Aromatase inhibitors, Rat, Sexual activities, Testes histopathology

Maternal aromatase inhibition via letrozole altered RFamide-related peptide-3 and gonadotropin-releasing hormone expression in pubertal female rats

Objective(s): Despite prevalence of polycystic ovary syndrome (PCOS) among childbearing women and development of many animal models for this syndrome, information on its etiology is still scarce. The intrauterine hyperandrogenic environment may underlie changes at the level of hypothalamus, pituitary, ovary organization in female offspring, and PCOS later in life. Letrozole has been shown to mimic reproductive and metabolic characteristics of PCOS in adult rodent models. Therefore, this research aimed to assess the condition in a prenatal letrozole-treated rat model. Materials and Methods: Twenty-eight female rats dams receiving letrozole at certain doses during late pregnancy were used in the trial. Pregnant Sprague-Dawley rats (n=21) received letrozole treatment on gestation days 16–18 at doses of 1.25, 1.0, 0.75, 0.5, and 0.25 mg/kg body weight (BW). Results: Prenatal letrozole treatment delayed parturition time and reduced the litter size in pregnant dams (P<0.0001). Late puberty onset, irregular ovarian cyclicity, increased anogenital distance (AGD), body weight gain, serum testosterone concentration, and reduced estradiol levels (P<0.0001) were observed in the female offspring of dams receiving 1.25 and 1 mg/kg BW letrozole. Furthermore, letrozole at 1.25 and 1 mg/kg BW showed increased RFRP and decreased GnRH mRNA expression (P<0.0001). Letrozole treatment at doses of 1 mg/kg BW and lower was not fetotoxic. Conclusion: It was concluded that 1 mg/kg BW letrozole may be suggested for prenatal PCOS induction. Keywords Gonadotropin-releasing hormone Hypothalamus Letrozole Polycystic ovary syndrome Prenatal Rat RFamide-related peptide-

Trends in the reproductive performance of Holstein dairy cows in Iran.

peer reviewedThe study was undertaken to determine the trends in the reproductive performance of Holstein dairy cows in Iran during 1994 to 2008. Reproductive performance data for 528,034 lactations of 246,132 cows in 1,822 Holstein dairy herds of Iran were used. The potential effect of calving season, herd, parity, calving year, as well as herd size and 305-day milk production on reproductive performance traits was investigated using multiple regression models. The least squares means of age at first calving decreased by 3.1 (± 0.06) days per year from 806.5 (± 96.3) days in 1994 to 788 (± 89.9) days in 2008. The least squares means of calving interval increased 1.02 (± 0.03) days per year from 394.1 (± 65) days in 1994 to 413.2 (± 81) days in 2008. Greater 305-day milk production was associated with an average increase of 6.55 (± 0.08) days in calving interval per 1,000-kg increase in milk yield. Larger herd size was associated with an average decrease of 0.22 (± 0.02) days in calving interval per 50 cows per herd. The mean number of days dry was 88.6 (± 51.3) days and increased by 0.82 (± 0.02) days per year. In conclusion, reproductive performance in Holstein dairy herds has generally decreased, whereas herd size and milk production have increased over time. Producers may make significant improvements in herd reproduction by reviewing management strategies including the sire selection, reproductive management, inseminator training and techniques, and improved estrous detection. Moreover, it may be advisable for the fertility traits to be included in the genetic selection indices to reduce the rate of reproductive decline

Effect of Silymarin Against Lead Induced Oxidative Stress in Broiler Chicken

This study aimed to investigate the effect of different levels of silymarin against lead induced oxidative stress in broiler chickens. Therefore, 240 broiler chickens of Ross 308 allocated to 24 experimental units in a completely randomized design with factorial 2x3 arrangements and four replicates of 10 birds. The experimental diets containing silymarin at 3 levels (0, 100, 200 mg/kg) and 2 levels of lead (0, 200 mg/kg) were fed for 6 weeks. Results of this experiment showed that supplementation of 200 mg/kg silymarin attenuated adverse effect of lead on body weight gain (BWG) and feed conversion ratio (FCR) in 42 d. Also, addition of 200 mg/kg silymarin in lead-induced oxidative stress improved carcass characteristics. In addition, supplementation of silymarin in lead-induced oxidative stress no significantly decreased blood lipid parameters (cholesterol, triglyceride, LDL). Furthermore, supplementation of 200 mg/kg silymarin significantly increased superoxide dismutase (SOD) and decreased malondealdehyde (MDA) and heterophyle /lymphocyte (H/L ratio). These results suggested that supplementation of silymarin in lead induced oxidative stress had a protective role and by improving the antioxidant system improved the performance

Serum biochemical profile of sheep fed olive-pulp silage for extended period

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