In commercial pig production, piglets are often mixed after weaning which can result in severe aggression and lead to body damage, disruption of feeding behaviour and reduced growth. This experiment investigated whether application of a synthetic maternal pheromone to groups of weaned pigs in commercial housing would affect the level of aggression and skin lesions sustained after mixing. Two treatments (Pheromone and Control) were used with 16 replicate pens of pigs (20 pigs per pen). Treatments were applied on the day of weaning (average 28 days of age) on a per room basis in alternate weeks. In Pheromone pens, after routine washing and disinfection, the walls and feeders were treated one hour prior to occupation with a synthetic pheromone at a rate of 1.0 ml pig−1. Control pens were as for Pheromone except no product was applied. During the 24-h period, post mixing, pigs in pheromone-treated pens spent significantly less time fighting than those in control pens. This was reflected in reduced injury scores 24 h after mixing, with pigs in pheromone-treated pens having 39% fewer skin lesions on the front of the body compared to those in control pens. Treatment had no effect on growth rate or feed efficiency, although the feed intake for days 7–28 was significantly lower and feed efficiency tended to be lower in pheromone-treated pens. In conclusion, application of a synthetic maternal pheromone can be considered one of the arsenal of strategies to reduce aggression and safeguard the welfare of groups of weaned pigs where mixing is unavoidable.

The bovine appeasing substance (BAS) is expected to have calming effects in cattle experiencing stressful situations. Therefore, this study investigated the impacts of BAS administration during two of the most stressful events within beef production systems: weaning and feedlot entry. In experiment 1, 186 Bos indicus-influenced calves (73 heifers, 113 bulls) were weaned at 211 ± 1 days of age (day 0). At weaning, calves were ranked by sex and BW, and assigned to receive BAS (Nutricorp, Araras, SP, Brazil; n = 94) or water (CON; n = 92). Treatments (5 ml) were topically applied to the nuchal skin area of each animal. Calf BW was recorded and samples of blood and tail-switch hair were collected on days 0, 15 and 45. Calves that received BAS had greater (P < 0.01) BW gain from day 0 to 15 compared with CON. Overall BW gain (days 0 to 45) and BW on days 15 and 45 were also greater (P ≤ 0.03) in BAS v. CON. Plasma haptoglobin concentration was less (P < 0.01) in BAS v. CON on day 15, whereas cortisol concentrations in plasma and tail-switch hair did not differ between treatments (P ≥ 0.13). In experiment 2, 140 B. indicus-influenced bulls (∼27 months of age) from 2 different pasture-based systems (70 bulls/origin) were transported to a commercial feedlot (≤ 200-km transport; day -1). On day 0, bulls were ranked by source and BW, and assigned to receive BAS (n = 70) or CON (n = 70) and the same sampling procedures as in experiment 1. Bulls receiving BAS had greater (P = 0.04) BW gain from day 0 to 15, but less (P < 0.01) BW gain from day 15 to 45 compared to CON. No other treatment effects were detected (P > 0.14). Therefore, BAS administration to beef calves alleviated the haptoglobin response associated with weaning, and improved calf growth during the subsequent 45 days. Administration of BAS to beef bulls at feedlot entry improved BW gain during the initial 15 days, but these benefits were not sustained throughout the 45-day experiment.

The lesser date moth (LDM) Batrachedra amydraula is a significant pest of date palm fruits. Previously, detection and monitoring of the pest was inaccurate due to high costs of sampling with lifting machines. We report a practical system for detection and monitoring of LDM based on pheromone traps and relevant models. Dose–response experiments with LDM pheromone traps indicated a 1 mg lure is optimal for monitoring. Delta traps with adhesive covering their entire inner surface gave the highest captures while trap colour was unimportant. Sampling pheromone traps throughout the night indicated male flight began at 1:00–2:00 and reached a peak 2 h before sunrise. Monitoring traps exposed all year long in Israel revealed three generations with different abundance. Trapping transects in a date plantation indicated interference from a monitoring trap became minimal at distances >27 m away. Inter-trap distances closer than this may lower efficiency of monitoring and mass trapping in control programs. Our estimate of the circular effective attraction radius (EARc) of a 1 mg delta trap for LDM (3.43 m) shows this bait is among the most attractive compared with baits for other insects. We developed encounter-rate equations with the pheromone trap EARc to model the interplay between population levels, trap density and captures that are useful for detection of invasive LDM and its control by mass trapping. The integrated methodologies are applicable to many pest species.

Aggregation pheromones have been identified and tested in the field for Frankliniella occidentalis and Thrips palmi. These pheromones are produced by adult males and attract both males and females. They are likely to be widespread across the Thripidae and identification is in progress for several other pest species. Aggregation pheromones are used commercially for monitoring and activation. Field trials have shown they can be cost effective for mass trapping when used as part of an integrated pest management (IPM) programme. Use for other approaches, such as lure and kill and mating disruption have not yet been tested. A better understanding of the role of these pheromones in the mating behaviour of thrips is needed and this may suggest further ways of developing their potential for pest management.

Trapping of adult red palm weevil (RPW) Rhynchophorus ferrugineus Olivier using food-baited pheromone traps is a major component of the integrated pest management strategy currently adopted against the RPW in the United Arab Emirates (UAE). Field trials were carried out in RPW-infested date plantations of Al-Rahba, Abu Dhabi, UAE from January to December 2010 to ascertain the combined influence of ethyl acetate (EA) and trap colours on weevil captures in RPW pheromone traps. Weevil captures were recorded throughout the experimental period with a sex ratio (male:female) of 1:2.2 and capture rates of 25.13 and 15.14 weevils/trap/month in traps with and without EA, respectively. Furthermore, treatments with black-coloured traps recorded significantly higher weevil captures.

Megaplatypus mutatus (=Platypus sulcatus Chapuis) is an Ambrosia beetle native to South America, which was recently introduced in Italy and its presence there is causing severe damage to the local poplar plantations. The male M. mutatus pheromone is composed of (S)-(+)-6-methyl-5-hepten-2-ol [(+)-sulcatol], 6-methyl-5-hepten-2-one (sulcatone) and 3-pentanol. A series of field trials testing dose, blend and enantiomer composition performed in Argentina and Italy evaluated attraction and found that the optimal release rate of pheromone components as baits in cross vane baited traps (CIPEIN-CV) was 6, 6 and 30 mg day−1 of sulcatone, (+)-sulcatol and 3-pentanol, respectively. It was also determined that racemic sulcatol is as effective as the pure (+)-isomer for the purpose of beetle catch, due to the inert nature of the (−)-isomer allowing the usage of low cost racemic sulcatol instead of highly expensive (+)-sulcatol. The results of our work contribute to the development of pheromone-based local technologies with low environmental impact and low cost for control or monitoring of an important pest.

All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to females. While some host-plant odours are known to enhance specific attraction of aphid species, herbivore-induced plant volatiles that synergise attractiveness to the sex pheromone are unknown. Here, we demonstrate that for the host-alternating rosy apple aphid (Dysaphis plantaginea (Passerini)) specificity of attraction of males to females is triggered by female-induced tree odours in combination with a 1:8 ratio of (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol. Female aphid infestation induces increased release of four esters (hexyl butyrate, (E)-2-hexenyl butyrate, (Z)-3-hexenyl 3-methylbutyrate and hexyl 2-methylbutyrate) from apple leaves. Two different combinations of three esters applied in a 1:1:1 ratio increase the number of male D. plantaginea and decrease the number of other aphid species caught in water traps in the presence of the pheromone components. The ester blend alone was not attractive. Combination of the pheromone blend with each single ester was not increasing attraction of male D. plantaginea. The demonstration that sexual aphid species use herbivore-induced plant volatiles as a species-specific attractant for mate finding adds a new dimension to our understanding of insect species using or manipulating chemical cues of host plants for orientation.

Cocoon-spinning larvae of the codling moth, Cydia pomonella, emit a pheromone that mediates aggregation by pupation site-seeking fifth-instar larvae. It was unknown and, thus, we tested whether the aggregation pheromone induces arrestment or attraction responses. In paired straight-tube experiment 1, fifth-instars moved faster and farther upwind toward cospecific cocoons compared to blank controls. In still-air cage experiment 2, fifth-instars selected more often as first and final choices of pupation sites those with cocooning conspecifics than those without. Finally, in Y-tube olfactometer experiment 3, fifth-instars anemotactically responded to, and preferred, side arms with cocooning conspecifics to those without. Our data provide evidence that codling moth larvae are attracted to, rather than merely arrested by, larval aggregation pheromone. These results help explain reported aggregations or clumped distributions of larvae on tree trunks, which would likely not occur if they were based merely on chance encounter of cocoon-spinning larvae by foraging larvae.

Sex pheromonal components of the tephritid fruit fly Bactrocera dorsalis (Hendel), 2-allyl-4,5-dimethoxyphenol and (E)-coniferyl alcohol, are biosynthesized from a highly potent male attractant, methyl eugenol, then sequestered and stored in the rectal gland prior to their release during courtship at dusk. These sex pheromonal components have been detected in the haemolymph and crop organ. Hence, attempts were made to separate and identify the haemolymph fractions which contained the sex pheromonal components. Identification of these bioactive fractions in methyl eugenol-fed male flies using gel filtration column chromatography and biodetection using live male flies showed two fractions as highly attractive to conspecific males. These fractions show a significant increase in protein absorbance in the elution profile of haemolymph from methyl eugenol-fed males compared with that from methyl eugenol-deprived males. The molecular mass of these bioactive fractions as determined by using gel filtration was in the peptide range of 3.3 to 5.5 kDa. Subsequent gas chromatography–mass spectrometry analyses further confirmed the presence of the pheromonal components in the bioactive fractions. The presence of these methyl eugenol-derived sex pheromonal components in specific haemolymph fractions suggests the involvement of a sex pheromone binding complex.

Studies were conducted using a water-based trap baited with the synthetic female sex pheromone to gain further understanding on the effect of trap height and spacing in relation to crop height on catches of males of the millet stemborer, Coniesta ignefusalis (Hampson) (Lepidoptera: Pyralidae). Regardless of crop height, catches were greatest at trap heights of 0.10 and 0.50 m when the traps were stacked vertically. When traps were sited singly at 50 m spacing there was no significant difference in catches at the different heights. When trap spacing was varied from 50,15, 5,1 to 0 m, male moth catches in traps increased at lower trap heights, regardless of crop height. Comparison of catches in light traps and pheromone-baited traps showed a significant positive correlation. These findings have implications for both monitoring and development of millet stemborer control systems through mating disruption and mass trapping.

Recent studies on the identification and evaluation of the millet stemborer Contesta ignefusalis female sex pheromone have shown that pheromone technology is promising as a management component. A review of research shows that an effective pheromone trap has been developed and successfully tested in eight countries in West Africa, through the West and Central African Millet Research Network (WCAMRN/ROCAFREMI). A regional wide-scale stemborer monitoring network has been developed and is being implemented. Studies on mass trapping and mating disruption indicate that the two techniques have much potential in C. ignefusalis management. Prospects for the implementation of pheromone technology to manage C. ignefusalis in the context of an IPM scheme are discussed.

Female sex pheromone components have been identified for seven species of Chilo, pests of cereals and sugar-cane. Synthetic pheromone blends for C. suppressalis, C. sacchariphagus, C. sacchariphagus indicus, C. auricilius and C. zacconius have shown satisfactory attractiveness to male moths in the field. Blends for C. partellus and C. infuscatellus seem to be incomplete. Pheromones and related compounds have been investigated for control of C. suppressalis by mating disruption in the Philippines, Japan, Spain and Korea. These studies have shown not only trap catch reduction, but also reduced viable egg production in field cages and effective control of damage by this pest on areas up to 60 ha. Initial studies have been carried out on control of C. sacchariphagus by mating disruption in Mauritius, and both the pheromone and an inhibitor have been shown to cause trap catch reduction of C. auricilius in India. Attempts have been made to control C. sacchariphagus indicus by mass trapping in India.

This paper reports observations made on the sensory biology of Chilo partellus larvae and adults. The larval and adult antennae of this insect have hygro/thermosensitive sensilla equipped with receptor cells sensitive to minute changes in temperature. Inputs through those cells may partly be responsible for the light evasive and other light/temperature-dependent behaviour patterns. The grooved basiconic sensilla especially those found on the male antennae are sensitive to the female sex pheromone components of C. partellus. Host-plant odours are most likely perceived by one or two of the other antennal olfactory sensilla, namely the smooth-surfaced basiconica and coeloconica sensilla. Chilo partellus moths have a limited number of gustatory sensilla on the tarsi, ovipositor, antennae and the proboscis. Electrophysiological bioassays done on the ovipositor and tarsal sensilla are discussed. Similar tests on the larval maxillary styloconica sensilla showed that the lateral and medial sensilla differed in their sensitivity. Their taste receptor cells can detect differences between saps from susceptible and resistant host-plants.

The flight phenology of the stem borer, Chilo partellus (Swinhoe) at the ICIPE's Mbita Point Field Station (MPFS) and on a nearby farmer's field was monitored using pheromone traps. The relation between pheromone trap catches of males and sorghum plant age, infestation, larval/pupal population density and sorghum cultivars used was examined. At MPFS C. partellus males were caught throughout the year in pheromone traps. Fluctuations of trap catches indicated that the pest completes two main generations on each of the long and short rain sorghum crops. On farmers' fields, males continued to be caught in large numbers after harvest, implying that the pest continues to breed on the sorghum stalks and tillers. Significantly lower observed catches of males occurred only on one (MB-3) of the eight different sorghum cultivars, during the period of 2–6 weeks after plant emergence. In general, positive correlations were observed between the number of males caught in pheromone traps and larval pupal population density, males and percentage plants infested, and males and plant age. However, the pheromone trap appeared to be less effective under high population density, particularly during the flight of the second generation moths, due to competition between pheromone trap and wild females. But the flight phenology as monitored by pheromone traps appeared to reflect major events in population development of C. partellus. Pheromone traps would be useful in detecting C. partellus and for monitoring its flight phenology.

Selected studies in chemical ecology are described that have led to the identification of semiochemicals playing key roles in pest behaviour. In some instances, these compounds can provide alternatives to insecticides, but novel integrated control programmes including use of semiochemicals are described which have greater potential for the future. Thus, semiochemicals can be used to increase the efficacy of entomophagous fungi and to manipulate populations of beneficial insects. New strategies are being developed which use both antifeedant and attractant semiochemicals to deter insects from crops and aggregate them in areas where they can be destroyed. For the long term, strategies are described that employ genetic manipulation of crop plants so that pests are controlled by semiochemicals produced directly in the plants.

EAG recordings revealed that from the six substances isolated so far from pheromone glands of Marnestra brassicae females, only (Z)-11-hexadecenyl acetate (Z11-16Ac), (Z)-9-hexadecenyl acetate (Z9-16Ac) and (Z)-11-heptadecenyl acetate (Z11-17Ac) are perceived by the males. This suggests that these substances may be female sex pheromone components.

The male olfactory sensilla also respond to (Z)-9-tetradecenyl acetate (Z9-14Ac) and (Z)-11-hexadecenol (Z11-160H), which are sex attractant constituents of various closely related species, but act as strong attractant inhibitors on M. brassicae males. This sensitivity to Z9-14Ac and Z11-160H is suggested to enhance the males' possibility to discriminate between conspecific and non-conspecific females.

Single sensillum recordings revealed that in 90% of the male antennal sensilla trichodea tested, three cell types (Types A, B, and C) were active. In the remaining 10% only B and C action potentials were seen. The Type C cells are exclusively responsive to the major pheromone component Z11-16Ac. The Type C cells are activated by the attractant inhibitors Z9-14Ac and Z11-160H, and to a small extent by Z11-16Ac. Responses to mixtures of these substances revealed that addition of Z9-14Ac and Z11-160H to Z11-16Ac changed the activity of the A cells only and did not affect the activities of the A and C cells. It is concluded that volatiles which exclusively or predominantly activate the Type B cells induce avoidance behaviour in the males, whereas substances activating the Type C cells evoke sexual behaviour and are attractive. This offers possibilities for relatively rapid electrophysiological determination of substances inducing sexual or avoidance behaviour. The function of the A cells is not yet clear. These cells respond to low concentrations of Z11-16Ac and Z11-160H, which may enhance the males' capacity to distinguish conspecific from non-conspecific females at a distance, when concentrations are low and the C and B cell activities are small.

It is suggested that cells sensitive to Z9-16Ac and Z11-17Ac are present in a limited number of sensilla only.

Pheromone traps were used for monitoring flight activity of peach twig borer, Anarsia lineatella (Zeller), during a 3 year period between 1983–1985 in Iraq at Tarmiya and Madain regions, and cumulative emergence was related to physiological time (degree-days, DDs). Data of moth catches indicated the presence of two generations per year and perhaps a partial third generation. Flight in both regions peaked from April to mid-May and from early June to mid-June. First capture of peach twig male ranged from 16 to 29 March and corresponded to a mean DD accumulation from 1 March of 138 in Tarmiya and 127 in Madain. Such results are very important for managing this pest.

Studies have shown that the East African mosquito strain, Culex pipiens fatigans, is attracted to a synthetic oviposition attractant pheromone in the laboratory. Chemical analysis has shown that the main volatile component of the apical droplets is (—)-(5R,6R) erythro-6-acetoxy-5-hexadecanolide. In contrast to the lack of response in the Sri Lankan strain of the same mosquito, the East African strain shows remarkable similarity in attraction response to the West African, American and Japanese strains of C. p. fatigans.

Twelve models are presented to examine the feasibility of using pheromone baited traps containing chemosterilant for pest control, and to compare the efficiency of this method with the use of (i) pheromone baited traps containing insecticide, and (ii) sterile releases. It was found that the number of matings per individual has little effect on the efficiency of population control, whereas immigration of even a relatively small number of the pest species severely limits this method in its ability to control the population. The existence of density-dependent regulation on the other hand greatly enhances the effectiveness of this control method. If the birth rate greatly exceeds one young per adult per day, then the method using chemosterilants is approximately twice as efficient as either insecticides in the pheromone traps or the release of sterile males. However, if the birth rate is much less than one per day, as in tsetse, then chemosterilants are very much more efficient than either method. These differences in relative efficiency appear to depend on the frequency of mating relative to the birth and mortality rates.

Effects of pheromone trap design and trap placement methods were tested for catching males of the peach twig borer Anarsia lineatella (Zeller), in Iraq. Zoecon's pherocon lc trap captured more moths than corrugated plastic delta trap.

Significantly more moths were caught in traps hung at a height of 3.0 m above ground (surface) than at any other level of traps. Although more males were caught in the traps placed in south quadrant of the trees than other quadrants, the analyses showed that there was no significant difference between quadrants at P = 0.05. Response to traps at the interior of the orchard was significantly higher than that to the traps in perimeter orchard.