Dietary incorporation of magnetic bentonite nanocomposite: impacts on in vitro fermentation pattern, nutrient digestibility, and growth performance of Baluchi male lambs.

Background: Incorporation of bentonite into the diets of ruminants can be helpful to maximize their performance. Modifying the structure of bentonite to nano and nanocomposite has improved their chemical stability and physicochemical properties, enhancing adsorption, absorption, and cation exchange capacity. Aims: This study aimed to assess the effect of magnetic bentonite nanocomposite (MBNC) on in vivo and in vitro fermentation process patterns, nutrient digestibility, and growth performance of Baluchi male lambs. Methods: Effects of control (basal diet), natural bentonite (NB) (10 g/kg dry matter (DM)), processed bentonite (PB) (5 and 10 g/kg DM basal diet), and MBNC (5 and 10 g/kg DM basal diet) on gas production (GP), and the fermentation process were determined using in vitro GP technique. For the in vivo experiment, 20 Baluchi male lambs were used with 4 experimental treatments: control, NB (5 g/kg DM), PB (5 g/kg DM), and MBNC (5 g/kg DM) and 5 replications in a completely randomized design for 60 consecutive days. Results: The potential for GP and its fractional rates were significantly decreased and increased in MBNC, respectively (P<0.01). The lowest cumulative GP, and CH4 yield were observed in MBNC (P<0.05). In vitro, DM and organic matter (OM) digestibility and all fermentation parameters increased with the addition of two levels of MBNC to the culture medium (P<0.01). Except for feed conversion ratio (FCR), other growth performance parameters increased with the addition of MBNC to the diet (P<0.01). The ruminal pH, total volatile fatty acids (TVFA), acetate, and propionate significantly increased when MBNC incorporated to the diet (P<0.01). The NH3-N (P<0.001) was significantly decreased in MBNC. The bentonite supplementation decreased acetate to propionate (P=0.001) compared to the control. Conclusion: Adding MBNC at the 5 g/kg diet DM level can be used as a useful supplement to optimize rumen fermentation pattern, reduce methane production, and increase lamb performance.

Estimation of gestational age using ultrasonography in Baluchi sheep.

The aim of this study was to evaluate the correlation between some fetal parameters measured by ultrasonography and fetal age for developing a formula which could be used for estimation of fetal age in Baluchi sheep. Placentome diameter (PD), gestation Sac diameter (GSD), biparietal diameter (BPD), straight crown-rump length (CRL), femural length (FL), occipito-snout diameter (OSD), thoracic diameter (TD) and fetal heart rate (FHR) were measured by transrectal and/or transabdominal ultrasonography. All ewes were synchronized using progesterone sponge for 6 days. On the first day, they received PGF2 and on the last day received 400 IU of equine serum gonadotrophin (eCG). All of the parameters revealed significant correlation by increasing fetal age. Except for PD, for other values linear regression curve was illustrated. BPD (between 36 - 96 days) (R2 = 0.961), CRL (R2 = 0.935), FL (R2 = 0.950), OSD (R2 = 0.981), TD (R2 = 0.975) showed high correlation with fetal age (p < 0.001). Moderate correlation was calculated for FHR (p < 0.001, R2 = 0.883). Low correlations were assessed by measurement of GSD (p = 0.018, R2 = 0.318), BPD (between 96-138 days; p = 0.038, R2 = 0.29) and PD represented the significant non-linear correlation with age (p < 0.001), maximum correlation was assessed by measurement of mean placentome wall diameter. In conclusion, OSD was recommended as the best parameter for estimating of gestational age between days 36 - 109 in Baluchi sheep because of the lowest residuals, the highest correlation coefficient and wide period of availability for imaging in gestation.

Inbreeding affected differently on observations distribution of a growth trait in Iranian Baluchi sheep.

OBJECTIVE: Initial consequence of inbreeding is inbreeding depression which impairs the performance of growth, production, health, fertility and survival traits in different animal breeds and populations. The effect of inbreeding on economically important traits should be accurately estimated. The effect of inbreeding depression on growth traits in sheep has been reported in many breeds. Based on this, the main objective of the present research was to evaluate the impact of inbreeding on some growth traits of Iranian Baluchi sheep breed using quantile regression model. METHODS: Pedigree and growth traits records of 13,633 Baluchi lambs born from year 1989 to 2016 were used in this research. The traits were birth weight, weaning weight, six-month weight, nine-month weight, and yearling weight. The contribution, inbreeding and co-ancestry software was used to calculate the pedigree statistics and inbreeding coefficients. To evaluate the impact of inbreeding on different quantiles of each growth trait, a series of quantile regression models were fitted using QUANTREG procedure of SAS software. Annual trend of inbreeding was also estimated fitting a simple linear regression of lamb's inbreeding coefficient on the birth year. RESULTS: Average inbreeding coefficient of the population was 1.63 percent. Annual increase rate of inbreeding of the flock was 0.11 percent (p<0.01). The results showed that the effect of inbreeding in different quantiles of growth traits is not similar. Also, inbreeding affected differently on growth traits, considering lambs' sex and type of birth. CONCLUSION: Quantile regression revealed that inbreeding did not have similar effect on different quantiles of growth traits in Iranian Baluchi lambs indicating that at a given age and inbreeding coefficient, lambs with different sex and birth type were not equally influenced by inbreeding.

Assessment of between-founder heterogeneity in inbreeding depression for reproductive traits in Baluchi sheep.

Magnitude of inbreeding depression could be different among descendants of various founder animals, when recessive genetic composition of a population is unevenly distributed among founder animal genomes. Reproductive records of Baluchi sheep for the litter variables size at birth (LSB), size at weaning (LSW), mean weight/lamb born (LMWLB), mean weight/lamb weaned (LMWLW), total weight at birth/ewe lambing (TLWB) and total weight at weaning/ewe lambing (TLWW) were used to examine heterogeneity in inbreeding depression between founder animals. Pedigree-based inbreeding coefficients were proportioned into components coming from founder animals and Mendellian contribution from non-founder animals. Two approaches were used to assess effects of inbreeding: overall inbreeding coefficients or partial inbreeding of the four main founder animals as possible covariates included in statistical models. Among the traits evaluated, there were effects on LMWLB, LMWLW and TLWW of inbreeding with there being a -8, -48, and -95 g decrease per 1% increase in inbreeding, respectively. Linear regressions of traits on partial inbreeding coefficients due to founder animals were of different magnitudes and ranged between -0.12 and +0.128. Heterogeneous contribution of founder animals to inbreeding depression occurred for LSB, LMWLB, and TLWW. These results indicate there was uneven distribution of recessive genetic composition among genomes of founder animals or differences in selection pressures on unfavorable alleles between different founder lines. The observed variation in founder-specific inbreeding depression indicates a small number of alleles with major effects are contributing to inbreeding depression.

Effects of phosalone consumption via feeding with or without sodium bentonite on performance, blood metabolites and its transition to milk of Iranian Baluchi sheep.

BACKGROUND: Transfer of pesticides from environment to animal products is inevitable, so the purpose of the present work was to evaluate phosalone consumption via feeding with or without sodium bentonite (SB) on performance, blood metabolites and its transition to milk of Iranian Baluchi sheep. METHODS: Twenty Baluchi ewes were divided into four treatments (P1 as control, P2, P3, and P4) of five animals in which phosalone, an organophosphate pesticide, was given via diet (only for P2 and P3) at a dose of 280 mg/sheep/day for 63 consecutive days. The SB (32 g/sheep/day; for P3 and P4) was also evaluated for its ability to reduce deleterious effects of phosalone in the sheep diets. The control group (P1) did not receive any phosalone and SB during the experiment. Sampling was conducted in two periods of time including weeks 5 and 9. RESULTS: Phosalone residues were observed in the milk samples of P2 and P3 groups during two sampling periods. During period 1, the transfer rate of phosalone from feed to milk was 0.23 and 0.02%, respectively for the contaminated diets (P2 and P3), which is relatively similar to period 2 (0.22 and 0.02%). Only 0.34 (period 1) and 0.36% (period 2) of phosalone residue are excreted in the feces of P2 group following its daily consumption. Transfer of phosalone from feed to milk was affected (P < 0.05) by the dietary inclusion of a commercial SB, as it (SB) decreased excretion of phosalone via milk (P3). The phosalone and SB alone or together had no significant effect (P > 0.05) on the dry matter intake (DMI) and body weight (BW) gain, but feed efficiency, milk production, milk fat, dry matter (DM) and organic matter (OM) digestibility, acetylcholinesterase (AChE) inhibitory activity, hemoglobin (Hb), red blood cell (RBC), serum glutamic pyruvic transaminase (SGPT), serum glutamic oxaloacetic transaminase (SGOT), albumin and mean corpuscular hemoglobin concentration (MCHC) affected by the treatments in period 1 or 2 (P < 0.05). The Hb, RBC, and MCHC were significantly decreased (P < 0.05) by about 9.72, 20.77, and 9.71%, respectively in the group P2 as compared to those of the control group during period 1. The AChE inhibitory activity (period 1 and 2) significantly increased when phosalone administered via the diet (P < 0.05). CONCLUSIONS: Although there were no adverse effects on the performance of sheep following the intake of phosalone alone (P2 vs. P1), but other research on the long and short times to the phosalone in high and low doses with more animals is suggested. Overall, compared to the control group, addition of SB in the diet of sheep improved nutrient digestibility, animal performance, and milk health.

Selenium-methionine and chromium-methionine supplementation of sheep around parturition: impacts on dam and offspring performance.

To examine the effects of maternal energy restriction along with selenium-methionine (Se-Met) and chromium-methionine (Cr-Met) supplementation on performance of pregnant sheep and their offspring, the following treatments were allotted randomly to 40 multiparous Baluchi ewes (53.9 ± 1.15 kg of body weight [BW]) from 5 weeks prior to 5 weeks after parturition: (1) Control diet (60% and 100% of NRC energy requirements in pre- and post-partum, respectively); (2) Control diet plus 5 mg Se-Met/kg dry matter (DM); (3) Control diet plus 3 mg Cr-Met/kg DM and (4) Control diet plus 5 mg Se-Met and 3 mg Cr-Met/kg DM (Se-Cr-Met) of concentrate diet. The results indicated that Cr-Met alone or in combination with Se-Met increased average DM intake of ewes. In addition, Group Cr-Met had higher average BW than the Control (p < 0.05). Se-Met and/or Cr-Met supplementation led to decreased average serum cholesterol of the ewes (p < 0.05). Groups Cr-Met and Se-Cr-Met displayed decreased average serum malondialdehyde compared to the Control (p < 0.05). At 24 h post-partum, Group Se-Cr-Met had a greater serum Se content than the Control (p = 0.006). Compared with the Control, the Se concentration in milk was significantly increased from 30 to 138 µg/l and 197 µg/l in Groups Se-Met and Se-Cr-Met, respectively (p < 0.01), which proved that Se-Met supplementation can increase the Se concentration of ewe milk. Furthermore, feeding Cr-Met may attenuate BW loss post-partum and Se-Met and/or Cr-Met supplements may ameliorate oxidative stress condition in ewes around parturition.