Comparative evaluation of the cost and efficiency of four types of sexing methods for the production of dairy female calves.

This study was conducted to evaluate and compare the economic benefits of different embryo sexing methods, based on the cost per female dairy calf produced. Female calves were produced from four kinds of female embryos: (1) those collected from superstimulated donors at 7-8 days after artificial insemination (AI) with X-sorted semen; (2) those sex-determined by loop-mediated isothermal amplification assay of a biopsy sample of embryos collected from superstimulated donors after AI with conventional unsorted semen; (3) those obtained by invitro embryo production (IVEP), using X-sorted semen and in vitro-matured oocytes collected from donors by ovum pick-up (OPU); and (4) those obtained by IVEP, using X-sorted semen and oocytes collected by OPU after dominant follicle ablation and follicle growth stimulation of the donors. The respective productivities of female calves per technical service and the total production cost per female calf of each sexing method were compared. The production cost per female calf (66,537 JPY), as calculated from the number of female calves per service (1.30), pregnancy rate of transfer (42.9%), rate of female calves obtained (92.9%), and total cost of the method (56,643 JPY plus embryo transfer fee), was less for IVEP with X-sorted semen and follicular growth-stimulated (FGS) oocytes than for the other groups (P < 0.05). The results demonstrate that embryo production with X-sorted semen and FGS oocytes provides a more efficient method for producing female calves than the other embryo sexing methods.

Economic evaluation of artificial insemination of sex-sorted semen on a Brown Swiss dairy farm-A case study.

Artificial insemination using sex-sorted semen is employed to efficiently increase the number of female dairy calves born. Previous studies have determined that using sex-sorted semen is beneficial to improve the management, but the mechanism by which it increases cattle numbers through objective indices of breeding remains unclear. This study focused on a Brown Swiss cattle herd in which frozen female sex-sorted semen was systematically employed to increase the number of cattle. We analyzed the correlation between the increase in the number of cattle and the screening accuracy of sex-sorted semen, measuring indices such as pregnancy rate and birth rate of female calves. Study revealed that: (1) production cost for female calves is influenced by the pregnancy rate, rate of female calves, and using sex-sorted semen is less expensive than using nonsorted semen; (2) improvements in screening accuracy nearly doubled the number of cows and tripled the number of heifers in 5 years; and (3) use of sex-sorted semen improved milk quality. The pregnancy rate was lower when sex-sorted semen was used, but the birth rate of heifers was improved. Results suggest that artificial insemination using sex-sorted semen is beneficial because it economically produces offspring to increase the herd.

Semiquantitative multi-analysis of plasma obtained from Romney lambs (Ovis aries) by inductively coupled plasma mass spectrometry, and the classification according to feed type.

The establishment of a classification system for domestic animals on consumed feed stuff is thought to be important from both a hygiene and market point of view. We collected plasma samples of Romney lambs (Ovis aries) which were fed one of the following: a herb-clover mix (n=10) which included chicory, red clover, white clover and plantain; a plant-grass mix (n=10) which included plantain, ryegrass and white clover; or a grass mix (n=10) which included ryegrass and white clover. A total of 20 elements in plasma samples obtained from the lambs were analyzed using inductively coupled plasma mass spectrometry. The data were then analyzed by principal component analysis. The lambs were divided into three groups on a score plot depending on the different feed conditions. Furthermore, discriminant analyses of the elements were examined, using linear discriminant analysis with forward stepwise regression. This discriminant function correctly classified the samples from each group. The accuracy of classification of each group, as shown by 10-fold cross-validation, proved the effectiveness of the established discriminant function. It is concluded that using linear discriminant analysis might be a useful tool for the validation of elements from plasma in lambs grown in different conditions.

A comparative analysis of acceptance by Japanese females and price of goat milk from different sources.

A sensory survey was carried out using 4 different types of whole goat milk among middle-class females to investigate consumer acceptability of goat milk and whether there is an opportunity to expand the sale of goat milk products in Japan. Four different types of whole milk powder (domestic concentrate-fed, domestic pasture-fed, USA commercially canned, and New Zealand commercially canned) were used. Fresh cow milk was served as a control. Thirty-one housewives evaluated the 5 liquid milk samples for smell, taste and overall characteristics on a scale of 1 (low) to 3 (high). Chi-square analyses were carried out to detect significant differences between the milk types in each category. The goat milk from the USA was the most preferred goat milk with respect to smell and overall evaluation. Domestic pasture-fed milk received the lowest grade in the evaluation for its 'grassy and goaty' smell. This result shows us that pasture intake affects the taste and smell of powdered milk which gives the lowest evaluation by the participants. If Japanese goat milk producers want to be successful in the domestic goat milk market and compete against goat milk products from other countries, they should improve production methods and flavor of their products.

Goat milk acceptance and promotion methods in Japan: The questionnaire survey to middle class households.

A consumer questionnaire conducted with the purpose of ascertaining the acceptability of goat milk and related products in Japan was carried out on 345 guarantees of Nippon Veterinary and Life Science University in December 2006. 275 effective responses (79%) representing middle class urban households were returned. The results revealed that (1) 30% of respondents have experienced drinking goat milk and only 10% are aware of the current retail situation of goat milk and related products; (2) over 70% of goat milk drinkers raised goats by hand at some point in their past and their first experience drinking goat milk was in infancy; (3) those with experience in drinking goat milk expressed a vague evaluation and minimal understanding of drinking goat milk; (4) respondents who were inexperienced goat milk drinkers expressed a strong desire to taste and a weak desire to purchase goat milk; (5) respondents expressed low recognition regarding retailed goat milk products, but those who had already purchased goat milk products expressed a high evaluation and strong desire to purchase these products again; and (6) recognition of goat milk characteristics is low, but those with high recognition also rate goat milk highly. Goats are perceived as being 'mild and familiar.' It is necessary for those who manage goat husbandry to present goat milk and related product tasting opportunities to consumers. The key point is to make the functional differences between cow and goat milk clear and present the advantages of goat milk at the fore of this promotion. Goat milk should not be promoted merely as a drink that is similar to cow milk, but must be positioned as a functional drink or health food in order to expand the Japanese goat milk market.