Embryonic Signals and Survival

The objective of this review is to give an overview of the signaling mechanisms between the conceptus and the mother before implantation. The interactions between the embryo and uterus are complex and essential for normal embryo development and implantation. Problems in the signaling mechanisms are thought to play a significant role in early embryonic mortality since a high rate of embryonic morality occurs during this period. This review will focus on the mechanisms involved in the development of the conceptus and the prevention of luteolysis. It is based primarily on what is known in ruminants but also refers to work in other species such as the mouse and primates.     

Impact of Buserelin Acetate or hCG Administration on the Day of First Artificial Insemination on Subsequent Luteal Profile and Conception Rate in Murrah Buffalo (Bubalus bubalis)

This study was designed to investigate the impact of buserelin acetate (BA) or human chorionic gonadotropin (hCG) administration on the day of first artificial insemination (AI) on subsequent luteal profile (diameter of corpus luteum (CL) and plasma progesterone) and conception rate in Murrah buffalo. The present experiment was carried out at two locations in 117 buffalo that were oestrus‐synchronized using cloprostenol (500 μg) administered (i.m.) 11 days apart followed by AI during standing oestrus. Based on treatment (i.m.) at the time of AI, buffalo were randomly categorized (n = 39 in each group) into control (isotonic saline solution, 5 ml), dAI‐BA (buserelin acetate, 20 μg) and dAI‐hCG (hCG, 3000 IU) group. Out of these, 14 buffalo of each group were subjected to ovarian ultrasonography on the day of oestrus to monitor the preovulatory follicle and on days 5, 12, 16 and 21 post‐ovulation to monitor CL diameter. On the day of each sonography, jugular vein blood samples were collected for the estimation of progesterone concentrations. All the buffalo (n = 117) were confirmed for pregnancy on day 40 post‐ovulation. The conception rate was better (p < 0.05) in dAI‐BA (51.3%) and dAI‐hCG (66.7%) groups as compared to their control counterparts (30.8%). Furthermore, the buffalo of dAI‐hCG group had improved (p < 0.05) luteal profile, whereas the buffalo of dAI‐BA group failed (p > 0.05) to exhibit stimulatory impact of treatment on luteal profile when compared to control group. In brief, buserelin acetate or hCG treatment on the day of first AI leads to an increase in conception rate; however, an appreciable impact on post‐ovulation luteal profile was observed only in hCG‐treated Murrah buffalo.     

Oil palm fiber (OPF) and its composites: A review

Twenty first century has witnessed remarkable achievements in green technology in material science through the development of biocomposites. Oil palm fiber (OPF) extracted from the empty fruit bunches is proven as a good raw material for biocomposites. The cellulose content of OPF is in the range of 43%–65% and lignin content is in the range of 13%–25%. A compilation of the morphology, chemical constituents and properties of OPF as reported by various researchers are collected and presented in this paper. The suitability of OPF in various polymeric matrices such as natural rubber, polypropylene, polyvinyl chloride, phenol formaldehyde, polyurethane, epoxy, polyester, etc. to form biocomposites as reported by various researchers in the recent past is compiled. The properties of these composites viz., physical, mechanical, water sorption, thermal, degradation, electrical properties, etc. are summerised. Oil palm fiber loading in some polymeric matrices improved the strength of the resulting composites whereas less strength was observed in some cases. The composites became more hydrophilic upon addition of OPF. However treatments on fiber surface improved the composite properties. Alkali treatment on OPF is preferred for improving the fiber–matrix adhesion compared to other treatments. The effect of various treatments on the properties of OPF and that of resulting composites reported by various researchers is compiled in this paper. The thermal stability, dielectric constant, electrical conductivity, etc. of the composites improved upon incorporation of OPF. The strength properties reduced upon weathering/degradation. Sisal fiber was reported as a good combination with OPF in hybrid composites.     

Real‐time quantification of the immune gene expression in rainbow trout fed different forms of probiotic bacteria Lactobacillus rhamnosus

Whether it is better to use viable or non‐viable probionts in aquaculture is still a matter of debate. In this study, the molecular immunomodulation in rainbow trout Oncorhynchus mykiss induced by viable or killed forms of the probiont Lactobacillus rhamnosus JCM 1136 was investigated. Three forms of this probiont: (1) heat‐killed (HK), (2) live spray (LI) and (3) freeze‐dried (FD) were incorporated into a basal (control) diet for rainbow trout O. mykiss. The LI and FD diets are referred to as viable diets. A rearing trial, in triplicate, was conducted for 30 days, with the control and probiotic diets as treatments. The cytokine genes such as the tumour necrosis factor (TNF), transforming growth factor (TGF‐β), interferon (IFN) and immune gene Immunoglobulin (Ig) found in tissues from the kidney and spleen were assessed for their expression pattern by real‐time polymerase chain reaction. The tested immune genes were up‐regulated in the treatment groups, sometimes even in many folds like in the case of the Ig gene. The TNF gene was found to be highly (P<0.05) up‐regulated (5000‐fold) in groups fed both viable forms (LI, FD). With regard to the TGF‐β gene, the spleen of the HK and FD groups showed significant up‐regulation of 20‐ and 30‐folds respectively. The IFN gene was up‐regulated (P<0.05) in all treatments, but more in the viable diet treatments. Kidney and spleen tissues showed similar expression patterns, i.e. all of these genes were up‐regulated more with the viable diets that with the control, and in most cases, the viable diets induced a higher expression of the immune genes than the HK diet.     

Moisture prediction from simple micrometeorological data

ABSTRACT Four linear regression methods and a generalized regression neural network (GRNN) were evaluated for estimation of moisture occurrence and duration at the flag leaf level of wheat. Moisture on a flat-plate resistance sensor was predicted by time, temperature, relative humidity, wind speed, solar radiation, and precipitation provided by an automated weather station. Dew onset was estimated by a classification regression tree model. The models were developed using micrometeorological data measured from 1993 to 1995 and tested on data from 1996 and 1997. The GRNN outperformed the linear regression methods in predicting moisture occurrence with and without dew estimation as well as in predicting duration of moisture periods. Average absolute error for prediction of moisture occurrence by GRNN was at least 31% smaller than that obtained by the linear regression methods. Moreover, the GRNN correctly predicted 92.7% of the moisture duration periods critical to disease development in the test data, while the best linear method correctly predicted only 86.6% for the same data. Temporal error distribution in prediction of moisture periods was more highly concentrated around the correct value for the GRNN than linear regression methods. Neural network technology is a promising tool for reasonably precise and accurate moisture monitoring in plant disease management.     

Effects on egg production of including high residual lipid copra meal in laying hen diets

1. The effects on egg production of including copra meals of 220.9 (Copra‐1) and 205.0 (Copra‐2) g residual lipids/kg, in laying hen diets at up to 400 g/kg, were examined in two feeding trials. In a separate experiment, the dry matter retention and ME of a 400 g Copra‐2/kg diet were determined between 6 to 9, 9 to 12 and 12 to 15 d of feeding.

2. Food intakes, egg output and efficiencies of food utilisation (g eggs/g food) of hens fed on Copra‐1 at 100 and 200 g/kg diet were not significantly different from controls; while food intakes at 400 g Copra‐1/kg diet were similar to controls, egg output (6.0% lower), efficiency of food utilisation and body weights of hens were significantly reduced. Hens fed Copra‐2 at 400 g/kg diet had 5.0 and 6.9% lower food intakes and egg output, respectively, and lost body weight compared to controls; however, egg output increased to that of the control group by the 11th week of feeding.

3. Initially, dry matter retention of the 400 g Copra‐2/kg diet was similar to, and ME slightly higher than the control diet; however, both were reduced significantly in the second and third collection periods. The water content of excreta from hens fed on 400 g Copra‐2/kg diet was significantly higher than that from controls.

4. Complete replacement of dietary maize, mainly with copra (experiment 1) led to an increase in pale yolks, with the 400 g Copra‐1/kg diet producing cream‐coloured yolks. Inclusion of maize at 180.6 g/kg of the 400 g Copra‐2/kg diet (experiment 2) resulted in eggs with slightly golden‐yellow yolks.     

Egg discolouration effects of including screw‐press cottonseed meal in laying hen diets and their prevention

The egg discolouration effects of including a screw‐press cottonseed meal (CSM), containing 68.2 g residual lipid/kg, 290 mg cyclopropenoid fatty acids (CPFA)/kg and 1226 mg free gossypol/kg, in laying hen diets at 300 g/kg were examined.

2. Discolouration prevention methods included treating the meal with ferrous sulphate heptahydrate (FSH), in solution or as crystals, at a 4:1 weight ratio of iron to free gossypol (experiment 1), and reducing its residual lipid (CSL) content to 4.2 g/kg by hexane extraction (experiment 2).

3. In freshly laid eggs, no discolouration was observed when hens were fed a CSM‐based diet containing 250 mg free gossypol/kg and 87 mg CPFA/kg in experiment 1, but slightly brown yolks were produced in experiment 2.

4. Storage of the eggs at 22°C led to yolk mottling, an effect believed to be the initial stages of the brown yolk discolouration.

5. Storage of the eggs at 5°C resulted in enhancement of the brown yolk discolouration, apricot discolouration on surfaces of most yolks and pink albumen discolouration. These effects were prevented when the CSM was extracted with hexane. Apricot yolk and pink albumen discolourations were also produced when hens were fed a non‐CSM diet containing crude CSL at 20.5 g/kg.

6. Dietary CSL increased egg fat saturation, altering the ratios of stearic to oleic, palmitic to palmitoleic and heptadecanoic to hepta‐decenoic fatty acids.

7. Treatment of CSM with FSH reduced the slight brown yolk discolouration in fresh eggs (experiment 2) and the yolk mottling in warm‐stored eggs. Both in solution and as crystals, FSH prevented the enhancement of brown yolk discolouration in cold‐stored eggs, leaving most eggs with apricot yolk and pink albumen discolourations.

8. Treatment of CSM and CSL with FSH reduced the CPFA‐related effects on yolk fat saturation, and the colour and pH changes in cold‐stored eggs.

9. Exposure of yolks to ammonia vapour provided a useful test to predict the development of the gossypol‐related brown discolouration in stored eggs.