Bangladesh Journal of Animal Science

Factors affecting iodine content of cow milk-A review

2024-03-31T07:59:57+00:00

This review discusses the importance of iodine as an essential nutrient for human health and the factors that can influence the concentration of iodine in cow milk. For an adult, the daily recommended requirement of iodine is 150 µg/day and the maximum tolerable limit ranges from 600 to 1100 µg/day. Cow milk is a significant source of iodine in many countries, particularly in areas where iodine-rich foods are not readily available. Therefore, evaluating the variables that affect the iodine content of cow milk is important. The iodine concentration of cow milk can vary depending on several factors such as genetics, diet, environment, management practices, season, and processing. Particularly, dietary supplementation and feed composition have been identified as the most impactful on milk's iodine levels, offering a practical approach to mitigating iodine deficiency. Furthermore, environmental factors like soil and water iodine content and management practices, including the type of farming, play substantial roles. Seasonal changes also significantly affect iodine levels, with higher concentrations typically observed in winter due to different feeding practices. The iodine content of cow milk falls between 147 to 605 µg/kg and the highest value of 11100 µg/L was recorded in camel milk. Milk could supply up to 60% of the daily dietary requirement of iodine for an adult person. To fight iodine deficiency through the appropriate approach to such concerns, one must have an in-depth understanding of these issues. This review paper aims to provide a comprehensive analysis of these factors and their implications for human and public health strategies.

Bangladesh Journal of Animal Science 53 (1): 1-12, 2024

Performances of upgraded Dwarf-Fayoumi chicken genotype in different feeding systems under smallholder farm management

2024-03-31T08:18:53+00:00

The experiment was conducted to evaluate the performance of upgraded Dwarf-Fayoumi genotype (IDC♂ × Fay♀) with three different feeding regimes from onset of lay to 72 weeks of age. A total of 90 IDC♂ × Fay♀ birds of third generation (F₃) at 16 weeks of age were distributed to 15 selected farmers nearby three villages of Bangladesh Agricultural University, Mymensingh. The villages were Kewatkhali, Boyra and Sutiakhali that selected for intensive, semi-scavenging and scavenging feeding systems, respectively. Each farmer was also given 5 pullets and 1 cockerel. The birds of full feeding and semi-scavenging system were given 76 g and 38 g mash feed per day, respectively. Pullets of semi-scavenging condition were allowed to scavenge in the farmer homesteads. The birds under scavenging condition reared without supplementation and were allowed to scavenge all day long. Result showed a significant difference (p<0.05) among the feeding systems (intensive, semi-scavenging and scavenging) in production and reproduction traits, where intensive full feeding system exerted better performances. However, performance efficiency index (52.24), egg-feed price ratio (2.81) and return over feed cost (4.48) were found to be significantly higher (p<0.001) in semi-scavenging feeding system. The egg weight (p<0.01), breaking strength (p<0.01) and dry yolk weights (p<0.05) were significantly lower in the birds reared under scavenging feeding system, however, these traits were found statistically similar in the birds of intensive and semi-scavenging feeding system. Feeding systems had no impact on survivability of the experimental birds. Taking altogether, it could be concluded that IDC♂ × Fay♀ upgraded chicken under semi-scavenging system performed better than intensive and scavenging system under smallholder farm management.

Bangladesh Journal of Animal Science 53 (1): 13-22, 2024

Casein, whey protein and non-protein nitrogen content of milk to identify water, sugar and flour adulterated milk

2024-03-31T09:15:49+00:00

This study was aimed to assess the potential of using milk's nitrogen distribution pattern, specifically casein, whey protein, and non-protein nitrogen content, as a method for detecting milk adulteration with water, sugar, and flour. Whole milk samples were collected from the Bangladesh Agricultural University Dairy Farm, BAU, Mymensingh, and subjected to adulterations, including 15%, 20%, and 25% water additions and subsequent sugar or flour adjustments to match the fresh milk's specific gravity. The samples were analyzed for specific gravity, fat content, and nitrogen distribution. Results indicated that while specific gravity remained consistent across samples adulterated with sugar or flour, it varied significantly (P<0.05) in those diluted with water. Fat content was significantly (P<0.05) reduced in samples adulterated with water and sugar, particularly at the 25% water addition level. Though total protein, true protein, and casein contents were significantly lower (P<0.05) in the 25% water-added milk compared to fresh milk, they were not significantly different (P>0.05) across the other adulterated samples when compared to fresh milk. Whey protein and non-protein nitrogen levels were statistically consistent (P>0.05) across all the samples. The results indicate that the nitrogen distribution pattern, in its current state, cannot be used to detect milk adulteration effectively. Further research with a larger dataset considering various factors affecting nitrogen distribution in milk is recommended for conclusive results.

Bangladesh Journal of Animal Science 53 (1): 23-30, 2024